Sediments contain a record of past environmental conditions. Studying the information contained in a group of sediments yields valuable clues about not only past environmental conditions, but also about how that environment has changed over time.
Open-File Report 2010-1172: Database of Recent Tsunami Deposits This report describes a database of sedimentary characteristics of tsunami deposits derived from published accounts of tsunami deposit investigations conducted shortly after the occurrence of a tsunami. The database contains 228 entries... Posted: 2010-09-28
Deepwater Horizon Oil Spill Response In order to assess and prepare for impacts from the Deepwater Horizon Oil Spill, the St. Petersburg Coastal and Marine Science Center is providing lidar, bathymetry, sediment core, and other data, as well as modeled scenarios of barrier-island inundation as the situation evolves. Posted: 2010-05-12
Archive of Digital Boomer Seismic Reflection Data Collected During USGS Field Activity 08LCA04 in Lakes Cherry, Helen, Hiawassee, Louisa, and Prevatt, Central Florida, September 2008 From September 2 through 4, 2008, the U.S. Geological Survey (USGS) and St. Johns River Water Management District (SJRWMD) conducted geophysical surveys in Lakes Cherry, Helen, Hiawassee, Louisa, and Prevatt, located in central Florida, as part of the USGS Lakes and Coastal Aquifers (LCA) study. This report serves as an archive of unprocessed digital boomer seismic reflection data, trackline maps, navigation files, Geographic Information System (GIS) files, and formal Federal Geographic Data Committee (FGDC) metadata. Filtered and gained (a relative increase in signal amplitude) digital images of the seismic profiles are also provided. Refer to the Acronyms page for expansions of acronyms and abbreviations used in this report. Posted: 2010-04-28
ATM Coastal Topography–Florida 2001: Eastern Panhandle This DVD contains Lidar-derived first surface (FS) topography GIS datasets of the eastern Florida panhandle coastline, from Shell Island to Mashes Island. These datasets were acquired October 2, 2001. Posted: 2010-04-21
ATM Coastal Topography–Florida 2001: Western Panhandle This DVD contains Lidar-derived first surface (FS) topography GIS datasets of the western Florida panhandle coastline, from Perdido Key to Lower Grand Lagoon. These datasets were acquired October 2-4 and 7-10, 2001. Posted: 2010-04-21
Open-File Report 2010-1037: Turbidity on the Shallow Reef off Kaulana and Hakioawa Watersheds, North Coast of Kaho‘olawe, Hawai‘i Measurements of Turbidity and Ancillary Data on Winds, Waves, Precipitation, and Stream flow Discharge, November 2005 to June 2008 The island of Kaho‘olawe has particular cultural and religious significance for native Hawaiians. Once known as Kanaloa, the island was a center for native Hawaiian navigation. In the mid-20th century, the island was used as a bombing range by the U.S. Navy, and that practice, along with the foraging by feral goats, led to a near-complete decimation of vegetation. The loss of ground cover led to greatly increased erosion and run-off of sediment-laden water onto the island’s adjacent coral reefs. Litigation in 1990 ended the U.S. Navy’s use of the island as a bombing range, and in 1994 the island was transferred to the Kaho‘olawe Island Reserve Commission (KIRC), http://kahoolawe.hawaii.gov/. As a result of the litigation, the U.S. Navy began a 10-year clean-up effort that was the foundation for the present restoration effort by KIRC (Slay, 2009). The restoration effort is centered on revegetating the island, reducing erosion, and limiting run-off onto adjacent reefs. Restoration efforts to mitigate sediment runoff to streams and gulches by restoring native vegetation and minimizing erosion have focused on two watersheds, Kaulana and Hakioawa, on the northeast and northwest sides of the island, respectively. Stream flow and sediment gages were installed by the U.S. Geological Survey Pacific Islands Water Science Center in each of the watersheds, and a weather station was established upland of the watersheds. For this study, turbidity monitors were installed on the insular shelf off the two watersheds to monitor the overall quality of reef waters and their changes in response to rain and stream flow discharge events. Posted: 2010-03-19
ATM Coastal Topography–Texas, 2001: UTM Zone 14 This DVD contains lidar-derived first-surface (FS) topography GIS datasets of a portion of the Texas coastline, within Universal Transverse Mercator (UTM) zone 14, from Mustang Island to Matagorda Peninsula. These datasets were acquired October 12-13, 2001. Posted: 2010-03-05
ATM Coastal Topography–Texas, 2001: UTM Zone 15 This DVD contains lidar-derived first-surface (FS) topography GIS datasets of a portion of the Texas coastline within Universal Transverse Mercator (UTM) zone 15, from Matagorda Peninsula to Galveston Island. These datasets were acquired October 12-13, 2001. Posted: 2010-03-05
ATM Coastal Topography–Mississippi, 2001 This DVD contains lidar-derived first-surface (FS) topography GIS datasets of the Mississippi coastline, from Lakeshore to Petit Bois Island. These datasets were acquired September 9-10, 2001. Posted: 2010-03-05
ATM Coastal Topography–Louisiana, 2001: UTM Zone 15 (Part 1 of 2) This DVD contains lidar-derived first-surface (FS) topography GIS datasets of a portion of the Louisiana coastline beach face within Universal Transverse Mercator (UTM) Zone 15, from Isles Dernieres to Grand Isle. These datasets were acquired September 7 and 10, 2001. Posted: 2010-03-05
ATM Coastal Topography–Louisiana, 2001: UTM Zone 16 (Part 2 of 2) This DVD contains lidar-derived first-surface (FS) topography GIS datasets of a portion of the Louisiana coastline beach face within Universal Transverse Mercator (UTM) Zone 16, from Grand Isle to the Chandeleur Islands. These datasets were acquired September 7 and 9, 2001. Posted: 2010-03-05
ATM Coastal Topography–Alabama 2001 This DVD contains Lidar-derived first surface (FS) topography GIS datasets of the Alabama coastline. These datasets were acquired October 3-4, 2001. Posted: 2010-03-04
Santa Barbara-Ventura Coastal Processes Study - USGS WCMG Santa Barbara/Ventura Coastal Processes Study of the USGS Western Coastal and Marine Geology Team. Whereas coastal urban development and infrastructure are largely fixed with respect to location, shoreline and bluff positions can change substantially over time in response to natural processes. These natural coastal changes can damage or undermine urban structures, resulting in substantial property loss for federal, state, local and individual land owners. Urban development can also indirectly influence coastal change by interrupting natural supplies or transport of sediment in littoral cells. Thus, it is important to evaluate the rates, patterns and causes of coastal change to better manage sediment resources and predict change hazards in coastal urban settings. The Santa Barbara and Ventura County coast represents a littoral cell along the California coast extending from (at least) Point Conception to the Mugu submarine canyon. The beaches along this littoral cell are an important economic resource to the region, and there is evidence that shoreline and bluff erosion are impacting these beaches. Coastal change in the Santa Barbara/Ventura region is complicated, however, by the irregular coastline (there are numerous rocky headlands, river deltas and offshore reefs), variability in wave forcing, structures such as harbors, groins, piers, dams and landscape urbanization, variability in tectonic uplift, and limited information on littoral sediment sources. In response to the potential for coastal change, BEACON (Beach Erosion Authority for Clean Oceans and Nourishment) and the City of Carpinteria have provided a combined $700K in funding for USGS WCMG to evaluate the coastal change patterns and processes along the Santa Barbara/Ventura County coast until the end of 2008. Posted: 2009-11-24
USGS Scientists in Samoa and American Samoa Studying Impacts of Recent Tsunami, October-November 2009 On September 29, 2009, a magnitude-8.0 submarine earthquake occurred at 6:48a.m. Samoa Standard Time approximately 190 km (120 mi) south of Samoa and triggered a tsunami that caused more than 100 deaths and widespread damage in Samoa, American Samoa, and Tonga. Observers reported four tsunami waves that ranged from approximately 1.5 to 6 m high and reached as far as 1.5 km inland. A rapid-response team of USGS scientists is traveling to American Samoa to collect data that will be quickly degraded or destroyed by recovery activity and natural processes. USGS Western Coastal and Marine Geology (WCMG) oceanographer Bruce Jaffe arrived in Pago Pago, on the island of Tutuila, American Samoa, on October 4 and was joined later in the week by fellow WCMG scientists Bruce Richmond, Mark Buckley, Guy Gelfenbaum, Steve Watt, and Alex Apotsos. Oceanographer Walter Dudley of the University of Hawai‘i, Hilo, will work with the USGS team. The team will collect time-sensitive data to help them determine the height of tsunami waves at various sites and the distances the waves traveled inland. They will study the transport of sediment and other debris, look for and measure evidence of subsidence and uplift caused by the earthquake, document erosion caused by the tsunami waves, and make other observations critical to the better understanding of tsunami impacts and processes. Posted: 2009-11-24
Open-FIle Report 2009-1190: 2008 Weather and Aeolian Sand-Transport Data from the Colorado River Corridor, Grand Canyon, Arizona This report presents measurements of weather parameters and aeolian (windblown) sand transport made in 2008 near selected archaeological sites in the Colorado River corridor through Grand Canyon, Ariz. The quantitative methods and data discussed here form a basis for monitoring ecosystem processes that affect archeological-site stability. Combined with forthcoming work to evaluate landscape evolution at nearby archaeological sites, these data can be used to document the relationship between physical processes, including weather and aeolian sand transport, and their effects on the physical integrity of archaeological sites. Data collected in 2008 reveal event- and seasonal-scale variations in rainfall, wind, temperature, humidity, and barometric pressure. Broad seasonal changes in aeolian sediment flux are also apparent at most study sites. The continuation of monitoring that began in 2007, and installation of equipment at several new sites in early 2008, allowed evaluation of the effects of the March 2008 high-flow experiment (HFE) on aeolian sand transport. At two of the nine sites studied, spring and summer winds reworked 2008 HFE sandbars to form new aeolian dunes, at which sand moved inland toward larger, well-established dune fields. At the other seven study sites, neither dune formation nor enhanced sand transport after the HFE were observed. At several of those sites, dominant wind directions in spring 2008 were not oriented such that much HFE sand would have moved inland; at other sites, lack of increased inland sand flux is attributable to lack of sandbar enlargement near the study sites or to inhibition of sand movement by vegetation or local topography. Posted: 2009-10-30
Open-File Report 2009-1195: Coastal Circulation and Sediment Dynamics in War-in-the-Pacific National Historical Park, Guam Flow in and around coral reefs affects a number of physical, chemical and biologic processes that influence the health and sustainability of coral reef ecosystems. These range from the residence time of sediment and contaminants to nutrient uptake and larval retention and dispersal. As currents approach a coast they diverge to flow around reef structures, causing high horizontal and vertical shear. This can result in either the rapid advection of material in localized jets, or the retention of material in eddies that form in the lee of bathymetric features. The high complexity and diversity both within and between reefs, in conjunction with past technical restrictions, has limited our understanding of the nature of flow and the resulting flux of physical, chemical, and biologic material in these fragile ecosystems. Posted: 2009-10-13
Scientific Investigations Report 2009-5116: Topographic Change Detection at Select Archeological Sites in Grand Canyon National Park, Arizona, 2006–2007 Topographic change of archeological sites within the Colorado River corridor of Grand Canyon National Park (GCNP) is a subject of interest to National Park Service managers and other stakeholders in the Glen Canyon Dam Adaptive Management Program. Although long-term topographic change resulting from a variety of natural processes is typical in the Grand Canyon region, a continuing debate exists on whether and how controlled releases from Glen Canyon Dam, located immediately upstream of GCNP, are impacting rates of site erosion, artifact transport, and the preservation of archeological resources. Continued erosion of archeological sites threatens both the archeological resources and our future ability to study evidence of past cultural habitation. Understanding the causes and effects of archaeological site erosion requires a knowledge of several factors including the location and magnitude of the changes occurring in relation to archeological resources, the rate of the changes, and the relative contribution of several potential causes, including sediment depletion associated with managed flows from Glen Canyon Dam, site-specific weather patterns, visitor impacts, and long-term climate change. To obtain this information, highly accurate, spatially specific data are needed from sites undergoing change. Using terrestrial lidar data collection techniques and novel TIN- and GRID-based change-detection post-processing methods, we analyzed topographic data for nine archeological sites. The data were collected using three separate data collection efforts spanning 16 months (May 2006 to September 2007). Our results documented positive evidence of erosion, deposition, or both at six of the nine sites investigated during this time interval. In addition, we observed possible signs of change at two of the other sites. Erosion was concentrated in established gully drainages and averaged 12 cm to 17 cm in depth with maximum depths of 50 cm. Deposition was concentrated at specific locations outside of drainages but generally was spread over larger areas (tens to hundreds of square meters). Maximum depths of deposition averaged 12 cm to 15 cm and reached as much as 35 cm. Overall, we found that the spatial distribution and magnitudes of surface change are specific to each site and that a thorough understanding of the geomorphology, weather, and sand supply is requisite for a complete understanding of the data. Additional work in combining these results with site-specific weather, hydrology, and geomorphology data will assist in the development of working models for determining the causes of the documented topographic changes. Posted: 2009-06-16
USGS Northern Gulf of Mexico (NGOM) The goal of the USGS Northern Gulf of Mexico project is to understand the evolution of coastal ecosystems on the Northern Gulf Coast, the impact of human activities on these ecosystems, and the vulnerability of ecosystems and human communities to more frequent and more intense hurricanes in the future. Posted: 2009-05-28
Scientific Investigations Report 2008-5094: Connections Among the Spatial and Temporal Structures in Tidal Currents, Internal Bores, and Surficial Sediment Distributions Over the Shelf off Palos Verdes, California The topography of the Continental Shelf in the central portion of the Southern California Bight has rapid variations over relatively small spatial scales. The width of the shelf off the Palos Verdes peninsula, just northwest of Los Angeles, California, is only 1 to 3 km. About 7 km southeast of the peninsula, the shelf within San Pedro Bay widens to about 20 km. In 2000, the Los Angeles County Sanitation District began deploying a dense array of moorings in this complex region of the central Southern California Bight to monitor local circulation patterns. Moorings were deployed at 13 sites on the Palos Verdes shelf and within the northwestern portion of San Pedro Bay. At each site, a mooring supported a string of thermistors and an adjacent bottom platform housed an Acoustic Doppler Current Profiler. These instruments collected vertical profiles of current and temperature data continuously for one to two years. The variable bathymetry in the region causes rapid changes in the amplitudes and spatial structures of barotropic tidal currents, internal tidal currents, and in the associated nonlinear baroclinic currents that occur at approximate tidal frequencies. The largest barotropic tidal constituent is M2, the principal semidiurnal tide. The amplitude of this tidal current changes over fairly short along-shelf length scales. Tidal-current amplitudes are largest in the transition region between the two shelves; they increase from about 5 cm/s over the northern San Pedro shelf to nearly 10 cm/s on the southern portion of the Palos Verdes Shelf. Tidal-current amplitudes are then reduced to less than 2 cm/s over the very narrow section of the northern Palos Verdes shelf that lies just 6 km upcoast of the southern sites. Models suggest that the amplitude of the barotropic M2 tidal currents, which propagate toward the northwest primarily as a Kelvin wave, is adjusting to the short topographic length scales in the region. Semidiurnal sea-level oscillations are, as expected, independent of these topographic variations; they have a uniform amplitude and phase structure over the entire region. Because the cross-shelf angle of the seabed over most of the Palos Verdes shelf is 1 to 3 degrees, which is critical for the local generation and/or enhancement of nonlinear characteristics in semidiurnal internal tides, some internal tidal-current events have strong asymmetric current oscillations that are enhanced near the seabed. Near-bottom currents in these events are directed primarily offshore with amplitudes that exceed 30 cm/s. The spatial patterns in these energetic near-bottom currents have fairly short-length scales. They are largest over the inner shelf and in the transition region between the Palos Verdes and San Pedro shelves. This spatial pattern is similar to that found in the barotropic tidal currents. Because these baroclinic currents have an approximate tidal frequency, an asymmetric vertical structure, and a somewhat stable phase, they can produce a non-zero depth-mean flow for periods of a few months. These baroclinic currents can interact with the barotropic tidal current and cause an apparent increase (or decrease) in the estimated barotropic tidal-current amplitude. The apparent amplitude of the barotropic tidal current may change by 30 to 80 percent or more in a current record that is less than three months long. The currents and surficial sediments in this region are in dynamic equilibrium in that the spatial patterns in bottom stresses generated by near-bed currents from surface tides, internal tides, and internal bores partly control the spatial patterns in the local sediments. Coarser sediments are found in the regions with enhanced bottom stresses (that is, over the inner shelf and in the region between the Palos Verdes and San Pedro shelves). Finer sediments are found over the northwestern portion of the Palos Verdes shelf, where near-bottom currents are relatively weak. The nonlinear asymmetries in the internal tidal-period current oscillations cause a net transport of suspended material along and off the shelf, reinforcing the mean flow patterns that also carry sediment either into Santa Monica Bay or offshore and onto the adjacent slope. Posted: 2009-05-28
Coastal Change During Hurricane Ivan 2004 Category 3 Hurricane Ivan came ashore near Gulf Shores, Alabama, on September 16, 2004. The barrier islands of the northern Gulf of Mexico near the Florida/Alabama border were exposed to the strongest winds. The communities of Gulf Shores, Pine Island and Orange Beach, AL, are, in places, very low lying with their dunes rising up only several meters. These dunes were unable to contain the 3-4 meter storm surge. Posted: 2009-04-07
Open-File Report 2009-1029: Coastal processes study of Santa Barbara and Ventura Counties, California By Patrick L. Barnard, David L. Revell, Dan Hoover, Jon Warrick, John Brocatus, Amy E. Draut, Pete Dartnell, Edwin Elias, Neomi Mustain, Pat E. Hart, and Holly F. Ryan. The Santa Barbara littoral cell (SBLC) is a complex coastal system with significant management challenges. The coastline ranges broadly in exposure to wave energy, fluvial inputs, hard structures, and urbanization. Geologic influence (structural control) on coastline orientation exerts an important control on local beach behavior, with anthropogenic alterations and the episodic nature of sediment supply and transport also playing important roles. Posted: 2009-03-27
Archive of Digital Boomer Seismic Reflection Data Collected During USGS Field Activity 08LCA01 in 10 Central Florida Lakes, March 2008 In March of 2008, the U.S. Geological Survey and St. Johns River Water Management District (SJRWMD) conducted geophysical surveys in Lakes Avalon, Big, Colby, Helen, Johns, Prevatt, Searcy, Saunders, Three Island, and Trout, located in central Florida, as part of the USGS Lakes and Coastal Aquifers (LCA) study. This report serves as an archive of unprocessed digital boomer seismic reflection data, trackline maps, navigation files, Field Activity Collection System (FACS) logs, Geographic Information System (GIS) files, and formal Federal Geographic Data Committee (FGDC) metadata. Filtered and gained (a relative increase in signal amplitude) digital images of the seismic profiles are also provided. Refer to the Acronyms page for expansions of acronyms and abbreviations used in this report. Posted: 2009-03-26
Archive of Digital Boomer and CHIRP Seismic Reflection Data Collected During USGS Field Activity 08LCA03 in Lake Panasoffkee, Florida, May 2008 In May of 2008, the U.S. Geological Survey (USGS) conducted geophysical surveys in Lake Panasoffkee, located in central Florida, as part of the USGS Lakes and Coastal Aquifers (LCA) study. This report serves as an archive of unprocessed digital boomer and Compressed High Intensity Radar Pulse (CHIRP)* seismic reflection data, trackline maps, navigation files, Field Activity Collection System (FACS) logs, Geographic Information System (GIS) files, and formal Federal Geographic Data Committee (FGDC) metadata. Filtered and gained (a relative increase in signal amplitude) digital images of the seismic profiles and geospatially corrected interactive profiles are also provided. Refer to the Acronyms page for expansions of acronyms and abbreviations used in this report. Posted: 2009-03-26
Open-File Report 2008-1191: Geologic Resource Evaluation of Kaloko-Honokōhau National Historical Park, Hawai‘i; Geology and Coastal Landforms Geologic resource inventories of lands managed by the National Park Service (NPS) are important products for the parks and are designed to provide scientific information to better manage park resources. Park-specific geologic reports are used to identify geologic features and processes that are relevant to park ecosystems, evaluate the impact of human activities on geologic features and processes, identify geologic research and monitoring needs, and enhance opportunities for education and interpretation. These geologic reports are planned to provide a brief geologic history of the park and address specific geologic issues that link the park geology and the resource manager... Posted: 2009-02-19
Open-File Report 2008-1192: Geologic Resource Evaluation of Pu‘uhonua O Hōnaunau National Historical Park, Hawai‘i; Part I, Geology and Coastal Landforms Geologic resource inventories of lands managed by the National Park Service (NPS) are important products for the parks and are designed to provide scientific information to better manage park resources. Park-specific geologic reports are used to identify geologic features and processes that are relevant to park ecosystems, evaluate the impact of human activities on geologic features and processes, identify geologic research and monitoring needs, and enhance opportunities for education and interpretation. These geologic reports are planned to provide a brief geologic history of the park and address specific geologic issues forming a link between the park geology and the resource manager... Posted: 2009-02-17
Scientific Investigations Report 2007-5101: The Coral Reef of South Moloka‘i, Hawai‘i—Portrait of a Sediment-Threatened Fringing Reef In this landmark volume, U.S. Geological Survey researchers and their colleagues have developed and applied a remarkably integrated approach to the reefs of Moloka‘i, combining geology, oceanography, and biology to provide an in-depth understanding of the processes that have made these reefs grow and that now limit them. They have joined old fashioned natural history of marine animals and plants with study of the geological evolution of the island, hydrology, meteorology, and land-use history, to an arsenal of new methods of remote sensing, including aerial photography, laser ranging, infrared thermal mapping, seismic reflection, in-situ instrumentation to measure chemical parameters of water quality, and direct measurements of the physical driving forces affecting them—such as wave energy, currents, sedimentation, and sediment transport. They provide a level of documentation and insight that has never been available for any reef before. Posted: 2008-11-19
USGS Data Series 265, Time-Series Photographs of the Sea Floor in Western Massachusetts Bay, Version 2, 1989 - 1996, USGS Data Series 265, Title Page This U.S. Geological Survey Data Series report presents time-series photographs of the sea floor obtained from an instrumented tripod deployed in western Massachusetts Bay (site LT-A, 42? 22.6' N., 70? 47.0' W., 32 m water depth) from December 1989 to October 1996. The photographs provide time-series observations of changes of the sea floor, near-bottom water turbidity, and life on the sea floor. The photographs, obtained every 4 or every 6 hours, are presented as individual photographs (in .png format) and as a movie (in .avi format). Posted: 2008-11-17
USGS Data Series 266, Time-series photographs of the sea floor in western Massachusetts Bay, 1996 - 2005 Title Page This U.S. Geological Survey Data Series report presents time-series photographs of the sea floor obtained from an instrumented tripod deployed in western Massachusetts Bay (site LT-A, 42? 22.6' N., 70? 47.0' W., 32 m water depth) from December 1989 to October 1996. The photographs provide time-series observations of changes of the sea floor, near-bottom water turbidity, and life on the sea floor. The photographs, obtained every 4 or every 6 hours, are presented as individual photographs (in .png format) and as a movie (in .avi format). Posted: 2008-11-17
USGS Open-File Report 2004-1358 The northern Gulf of Mexico contains many documented gas hydrate deposits near the sea floor. Although gas hydrate often is present in shallow subbottom sediment, the extent of hydrate occurrence deeper than 10 meters below sea floor in basins away from vents and other surface expressions is unknown. We obtained giant piston cores, box cores, and gravity cores and performed heat-flow analyses to study these shallow gas hydrate deposits aboard the RV Marion Dufresne in July 2002. This report presents measurements and interpretations from that cruise. Our results confirm the presence of gas hydrate in vent-related sediments near the sea bed. The presence of gas hydrate near the vents is governed by the complex interaction of regional and local factors, including heat flow, fluid flow, faults, pore-water salinity, gas concentrations, and sediment properties. However, conditions appropriate for extensive gas hydrate formation were not found away from the vents. Posted: 2008-11-17
Open-File Report 98-139: Multibeam Data and Socio-Economic Issues in West-Central San Francisco Bay Recent investigations by the USGS in the San Francisco Bay estuary help address both socio-economic and scientific issues: - How much rock must be trimmed from pinnacles on the bayfloor to provide safe navigation by deep-draft vessels? - What would be the environmental and societal consequences of a large oil spill? - What are the consequences of long-term dredging operations? - What types of bayfloor are important habitats for commercial and recreational fisheries? - What types of sediment cover the bayfloor? - What are the sediment distribution, volume, and rates of transport? Posted: 2008-10-10
Open-File Report 2008-1295: Coastal Circulation and Sediment Dynamics in Hanalei Bay, Kaua'i, Part IV, Measurements of Waves, Currents, Temperature, Salinity, and Turbidity, June-September 2006 High-resolution measurements of waves, currents, water levels, temperature, salinity and turbidity were made in Hanalei Bay, northern Kaua‘i, Hawai‘i, during the summer of 2006 to better understand coastal circulation, sediment dynamics, and the potential impact of a river flood in a coral reef-lined embayment during quiescent summer conditions. A series of bottommounted instrument packages were deployed in water depths of 10 m or less to collect long-term, high-resolution measurements of waves, currents, water levels, temperature, salinity, and turbidity. These data were supplemented with a series of profiles through the water column to characterize the vertical and spatial variability in water column properties within the bay. These measurements support the ongoing process studies being conducted as part of the U.S. Geological Survey (USGS) Coastal and Marine Geology Program’s Pacific Coral Reef Project; the ultimate goal is to better understand the transport mechanisms of sediment, larvae, pollutants, and other particles in coral reef settings. Information regarding the USGS study conducted in Hanalei Bay during the 2005 summer is available in Storlazzi and others (2006), Draut and others (2006) and Carr and others (2006). This report, the last part in a series, describes data acquisition, processing, and analysis for the 2006 summer data set. Posted: 2008-10-08
Professional Paper 1756: The Role of Eolian Sediment in the Preservation of Archeologic Sites Along the Colorado River Corridor in Grand Canyon National Park, Arizona This report summarizes a 3-year study of eolian sedimentary processes in the Colorado River corridor, Grand Canyon National Park, Ariz., and discusses the relevance of those processes to the preservation of archeologic sites. The results reported here are based on detailed sedimentologic and geomorphologic investigations in three reaches of the river corridor, as well as continuous measurements of wind, rainfall, and sand transport at six sites for as long as 26 months, short-term field study at 35 other sites, examination of historical aerial photographs, and review of data collected and analyzed during previous studies. The data generated by this study, which involved collaboration with scientists of the U.S. Geological Survey (USGS) Grand Canyon Monitoring and Research Center, the National Park Service, Northern Arizona University, the Hopi Tribe, and GeoArch, Inc., were previously published by Draut and Rubin (2005, 2006, 2008) and Draut and others (2005, in press). This report, which supersedes that by Draut and Rubin (2007), provides an overview of the results and contains new conclusions regarding eolian sedimentary processes in the Colorado River ecosystem and their relevance to the preservation of archeologic sites. Posted: 2008-09-24
WCMG Coastal Processes Studies California's beaches and nearshore regions are valuable economic and recreational resources but also provide habitats for numerous sensitive species. During winter storms, the coast represents a potentially dangerous interface between ocean and land, nature and humans. Storms produce high waves, strong currents, and elevated sea level that can rapidly erode beaches and inundate low-lying coastal regions, damaging and/or destroying public and private infrastructure as well as stressing coastal ecosystems. Over longer-time scales (e.g. decadal), persistent erosion exacerbated by the pressures of coastal development, reduction in sediment availability and climate change, can result in severely depleted beaches. The USGS performs research along the California coast to understand the physical processes that control coastal change on time scales from individual storms to decades to support the efforts of local, state and government agencies to make informed coastal management decisions to most effectively preserve and protect this valuable resource. Posted: 2008-09-23
Research Projects - USGS WCMG, Applied Sediment Transport There is an increasing need to understand, model, and predict, sediment transport and how it is impacted by dam construction, dam removal, dredging, beach nourishment, and other human and natural activities along the river/sea interface. This understanding of sediment routing from source to sink is necessary in order to remove obsolete or unsafe dams, change dam operations, or implement efforts to restore habitat in streams, rivers, and estuaries at the river/sea interface. Posted: 2008-09-23
Archive of Boomer Seismic Reflection Data - U.S. Geological Survey Open-File Report 01-165 This Open-File Report serves as an archive of field seismic data, associated navigation files, trackline map, scanned logbooks, and formal metadata, for boomer data collected on USGS Cruise 99ASR01. These data were recorded aboard the R/V G. K. Gilbert in Lake Okeechobee, Fla., on 29 June - 30 June, 1999. Posted: 2008-08-28
Coastal Processes: San Francisco Bight Coastal Processes Study - USGS WCMG San Francisco Bight Coastal Processes Study of the USGS Western Coastal and Marine Geology Team. The USGS is conducting a study that documents and analyzes the processes that control the sand transport and sedimentation patterns of Ocean Beach, a National Park site within the Golden Gate National Recreation Area. This area encompasses a complicated coastal setting that is impacted by the tidal influence of San Francisco Bay, as well as the southwest and northwest Pacific swell. High-energy conditions at this site have restricted comprehensive field surveys in the past, but recent innovations in field techniques now make it possible to perform detailed analysis of the physical processes operating on high energy coastlines, such as Ocean Beach. Posted: 2008-08-12
Open-File Report 2008-1327 - Interferometric Sidescan Bathymetry, Sediment and Foraminiferal Analyses; a New Look at Tomales Bay, California U.S.G.S. Open-File Report 2008-1327 entitled, Interferometric Sidescan Bathymetry, Sediment and Foraminiferal Analyses; a New Look at Tomales Bay, California. The United States Geological Survey (USGS) in collaboration with Point Reyes National Sea Shore (PRNS), and the Tomales Bay Watershed Council [http://www.tomalesbaywatershed.org/] has completed a detailed bathymetric survey, and sediment and foraminiferal analyses of the floor of Tomales Bay, California. The study goals are to detail the submarine morphology, the sediment distribution, sedimentary features, and distribution of foraminifera to provide a framework for future studies. The USGS collected swath bathymetric data with a SEA SWATHplus interferometric sidescan sonar system (2004, 2005) and an echo sounder system (2006). The data were processed into continuous mosaic images that show bathymetric detail of the bay floor with 0.2-m vertical and 4.0–m horizontal resolution. Acoustic backscatter data from the 2004 and 2005 surveys were processed into 2-m resolution grids. In addition, 27 sediment samples were collected from various parts of the bay for grain size analyses and a comprehensive study of the distribution of foraminifera in Tomales Bay. The foraminiferal analysis determined that the invasive foraminifera Trochammina hadai from Japan was present in Tomales Bay. The project was conducted in response to a request from the National Park Service, and the Tomales Bay Watershed Council who voiced a need to look at the environmental impacts of human input to the surrounding watersheds that ultimately flow into the bay. The mapping, sediment, and foraminiferal data establish a baseline survey for future comparisons of possible geologic and anthropogenic changes that might occur due to changes in land use or development in the surrounding watershed. These data may also aid in determining the possible pathways of pollutants entering the bay from the surrounding watersheds. Posted: 2008-07-31
Decision Support for Coastal Science and Management The Decision Support for Coastal Science and Management project, sponsored by the USGS Coastal and Marine Geology Program (CMGP) is supporting the creation of new capabilities for the synoptic remote sensing of coastal-marine and terrestrial environments based on aircraft and satellite sensors. These coastal remote-sensing, mapping, and point-monitoring tools constitute a unique integrated package of instrumentation and software that may be deployed in support of appropriately timed and scaled zoning decisions by management authorities in order to conserve and sensibly exploit nearshore coastal and marine ecosystems. Posted: 2008-07-15
Data Series 288: Beach Morphology Monitoring in the Elwha River Littoral Cell, 2004-2006 his report describes the methods used, data collected, and results of the Beach Morphology Monitoring Program in the Elwha River Littoral Cell, starting in 2004. The U.S. Geological Survey and the Washington State Department of Ecology collaborated in the data collection with the support of the local Lower Elwha Klallam Tribe. Beach monitoring efforts consisted of collecting topographic and bathymetric horizontal and vertical position data by using a Real Time Kinematic Differential Global Positioning System (RTK-DGPS). The monitoring program was designed to characterize the littoral system of the Elwha River before the scheduled removal of two large dams in 2012. A primary objective of this work is to quantitatively describe the topography and bathymetry of the Elwha River littoral system so that the effects of dam removal may be quantified. Sediment inputs following dam removal are hypothesized to result in (A) larger amounts of fine sediment grain-sizes entering the littoral system and, (B) a reduction or reversal of coastal erosion. Posted: 2008-07-11
Open-File Report 2008-1215: Winds, Waves, Tides, and the Resulting Flow Patterns and Fluxes of Water, Sediment, and Coral Larvae off West Maui, Hawaii A series of recent studies has focused on the flow patterns and particle fluxes along the coast of West Maui, Hawaii, USA, from Honolua south to Puumana. From those studies a relatively good understanding has emerged of the physical processes that influence the relative amount of suspended sediment in nearshore waters and the circulation patterns that transport sediment and coral larvae along the coast and between islands. This report is a synthesis of our existing knowledge on the nature of flow and transport off West Maui. Posted: 2008-07-02
Scientific Investigations Map 3007: Views of the Sea Floor in Northern Monterey Bay, California A sonar survey that produced unprecedented high-resolution images of the sea floor in northern Monterey Bay was conducted in 2005 and 2006. The survey, performed over 14 days by the U.S. Geological Survey (USGS), consisted of 172 tracklines and over 300 million soundings and covered an area of 12.2 km2 (4.7 mi2). The goals of this survey were to collect high-resolution bathymetry (depth to the sea floor) and acoustic backscatter data (amount of sound energy bounced back from the sea floor, which provides information on sea-floor hardness and texture) from the inner continental shelf. These data will provide a baseline for future change analyses, geologic mapping, sediment- and contaminant-transport studies, benthic-habitat delineation, and numerical modeling efforts. The survey shows that the inner shelf in this area is extremely varied in nature, encompassing flat sandy areas, faults, boulder fields, and complex bedrock ridges that support rich marine ecosystems. Furthermore, many of these complex bedrock ridges form the “reefs” that result in a number of California”s classic surf breaks. Posted: 2008-06-09
Archive of Sediment Data Collected from Sandy Point to Belle Pass, Louisiana, 1983 through 2000 (Vibracore Surveys: 00SCC, CR83, P86, and USACE Borehole Cores) In 2000, the U.S. Geological Survey (USGS), in cooperation with the University of New Orleans (UNO) and the U.S. Army Corps of Engineers (USACE), conducted geologic surveys in Barataria Bight from Sandy Point to Belle Pass, LA (Study Area Map). Sediment cores were collected as part of the USGS Subsidence and Coastal Change (SCC) Project, which included the Barataria Sand-Resource Study (bss) vibracore surveys (Kindinger and others, 2001). This report also contains information from other cruise data sets, including the Cheniere Ronquille, LA, data (CR83) and the Plaquemines, LA, data (P86). The sediment data for these cruises were obtained by the Louisiana Geological Survey (LGS), the Louisiana Department of Natural Resources (LDNR), and Alpine Ocean Seismic Survey, Inc., as part of the near shore sand resource inventory of "Louisiana Sand Resource Inventory 1985 Vibracore Services" (Suter and others, 1991; Alpine Ocean Seismic Survey, Inc., 1986). Additionally, this report also includes the U.S. Army Corps of Engineers EUSTIS borehole cores (B-#). EUSTIS is the type of drill rig used to obtain the borehole cores and is used as name identifier for the USACE borehole cores presented herein. These cores are presented on a separate map with links to the description profiles and grain-size data that can be found by clicking on the USACE EUSTIS link. Posted: 2008-06-01
Land Area Change in Coastal Louisiana: A Multidecadal Perspective (from 1956 to 2006) The U.S. Geological Survey (USGS) analyzed changes in the configuration of land and water in coastal Louisiana by using a sequential series of 14 data sets summarizing land and water areas from 1956 to 2006. The purpose of this study is to provide a spatially and temporally consistent source of quantitative information on land area across coastal Louisiana, broken into three physiographic provinces (the term "coastal Louisiana" is used to present data on the collective area). Posted: 2008-05-21
Data Series 320: Sea-Floor Mapping and Benthic Habitat GIS for the Elwha River Delta Nearshore, Washington This is a description of selected data layers for the Sea-Floor Mapping and Benthic Habitat GIS for Puget Sound, Washington. From March 1531, 2005, more than 252 km (19.5 km2) of seafloor offshore of the Elwha River Delta in the central Strait of Juan de Fuca was mapped by the USGS Coastal and Marine Geology Program. The purpose of this nearshore mapping was to (1) obtain high resolution bathymetry and acoustic reflectance properties of the seabed, (2) examine and record geologic characteristics of the seafloor, and (3) construct maps of sea-floor geomorphology and habitat. Substrate distribution was characterized with video-supervised statistical classification of the sonar data. Substrate of the survey was dominated by mixed sand-gravel and sand. Numerous boulder reefs were observed west of the river mouth within Freshwater Bay, whereas the sea-floor immediately adjacent to the river mouth was dominated by sand. Posted: 2008-05-07
Scientific Investigations Report 2008-5042: Update on Regulation of Sand Transport in the Colorado River by Changes in the Surface Grain Size of Eddy Sandbars over Multiyear Timescales In settings where the transport of sand is partially or fully supply limited, changes in the upstream supply of sand are coupled to changes in the grain size of sand on the bed. In this manner, the transport of sand under the supply-limited case is “grain-size regulated.” Since the closure of Glen Canyon Dam in 1963, the downstream reach of the Colorado River in Marble and Grand Canyons has exhibited evidence of sand-supply limitation. Sand transport in the river is now about equally regulated by changes in the discharge of water and changes in the grain sizes of sand on the channel bed and eddy sandbars. Previous work has shown that changes in the grain size of sand on the channel bed (driven by changes in the upstream supply of sand owing to both tributary floods and high dam releases) are important in regulating sand transport over timescales of days to months. In this study, suspended-sand data are analyzed in conjunction with bed grain-size data to determine whether changes in the sand grain size on the channel bed, or changes in the sand grain size on the surface of eddy sandbars, have been more important in regulating sand transport in the postdam Colorado River over longer, multiyear timescales. The results of this study show that this combined theory- and field-based approach can be used to deduce which environments in a complicated setting are most important for regulating sediment transport. In the case of the regulated Colorado River in Marble and upper Grand Canyons, suspended-sand transport has been regulated mostly by changes in the surface grain size of eddy sandbars. Posted: 2008-04-29
USGS-NPS-NASA EAARL Topography - Dry Tortugas National Park This lidar-derived submarine topography map was produced as a collaborative effort between the U.S. Geological Survey (USGS) Coastal and Marine Geology Program, National Park Service (NPS) South Florida/Caribbean Network Inventory and Monitoring Program, and the National Aeronautics and Space Administration (NASA) Wallops Flight Facility. One objective of this research is to create techniques to survey coral reefs for the purposes of habitat mapping, ecological monitoring, change detection, and event assessment (for example: bleaching, hurricanes, disease outbreaks). Posted: 2008-03-24
Scientific Investigations Report 2007-5254: Sources, Dispersal, and Fate of Fine Sediment Supplied to Coastal California We have investigated the sources, dispersal, and fate of fine sediment supplied to California coastal waters in a partnership between the U.S. Geological Survey (USGS) and the California Sediment Management Workgroup (CSMW). The purpose of this study was to document the rates and characteristics of these processes so that the State can better manage its coastal resources, including sediment. Posted: 2008-02-29
Scientific Investigations Report 2007-5233: Wave-Driven Spatial and Temporal Variability in Sea-floor Sediment Mobility in the Monterey Bay, Cordell Bank, and Gulf of the Farallones National Marine Sanctuaries Wind and wave patterns affect many aspects of continental shelves and shorelines geomorphic evolution. Although our understanding of the processes controlling sediment suspension on continental shelves has improved over the past decade, our ability to predict sediment mobility over large spatial and temporal scales remains limited. The deployment of robust operational buoys along the U.S. West Coast in the early 1980s provides large quantities of high-resolution oceanographic and meteorologic data. By 2006, these data sets were long enough to clearly identify long-term trends and compute statistically significant probability estimates of wave and wind behavior during annual and interannual climatic cycles (that is, El Niño and La Niña). Wave-induced sediment mobility on the shelf and upper slope off central California was modeled using synthesized oceanographic and meteorologic data as boundary input for the Delft SWAN model, sea-floor grain-size data provided by the usSEABED database, and regional bathymetry. Differences in waves (heights, periods, and directions) and winds (speeds and directions) between El Niño and La Niña months cause temporal and spatial variations in peak wave-induced bed shear stresses. These variations, in conjunction with spatially heterogeneous unconsolidated sea-floor sedimentary cover, result in predicted sediment mobility widely varying in both time and space. These findings indicate that these factors have significant consequences for both geological and biological processes. Posted: 2008-02-19
Open-File Report 2007-1412: Carpinteria Coastal Processes Study, 2005-2007; Final Report The United States Geological Survey (USGS), in collaboration with the University of California, Santa Cruz (UCSC), conducted a two-year study of the beach and nearshore coastal processes for the City of Carpinteria and adjacent beaches. The work was performed in response to and worked directly with the United States Army Corps of Engineers (USACE) Project Management Plan (PMP) for the City of Carpinteria: Carpinteria Shoreline, Santa Barbara County, California PMP (June 2003). Posted: 2008-02-04
The Massachusetts Bay Internal Wave Experiment, August 1998: Data Report, USGS DS 85, Version 2.0, Start Page This data report presents a description of the Massachusetts Bay Internal Wave Experiment (MBIWE) field program carried out in August 1998, an overview of the data through summary plots and statistics, and the time-series data in NetCDF format. The objective of this report is to make the data available in digital form and to provide summary plots and statistics to facilitate browsing of the data set. Posted: 2008-02-01
Open-File Report 2007-1216: Side-scan Sonar Imaging of the Colorado River, Grand Canyon This paper presents data collection methods and side-scan sonar data collected along the Colorado River in Grand Canyon in August and September of 2000. The purpose of the data collection effort was to image the distribution of sand between Glen Canyon Dam and river mile 87.4 before and after the 31,600 cfs flow of September 6-8. The side-scan sonar imaging focused on pools between rapids but included smaller rapids where possible. Posted: 2008-01-11
USGS Monterey Bay Science USGS Monterey Bay Science - USGS research in the Monterey Bay National Marine Sanctuary and coastal watersheds of central California Posted: 2008-01-01
USGS Coastal Change Hazards USGS Coastal Change Hazards - Focuses on hurricanes, tsunamis, sea-level rise, shoreline erosion, wetland destruction, and other issues relevant to coastal zone management and disaster preparedness. Posted: 2008-01-01
Coastal and Marine Knowledge Bank An initiative to develop and present a national-scale, interdisciplinary scientific framework for marine environments, the coastal zone, and coastal watersheds Posted: 2007-11-28
Professional Paper 1661-E: Seismic Stability of the Duwamish River Delta, Seattle, Washington The delta front of the Duwamish River valley near Elliott Bay and Harbor Island is founded on young Holocene deposits shaped by sea-level rise, episodic volcanism, and seismicity. These river-mouth deposits are highly susceptible to seismic soil liquefaction and are potentially prone to submarine landsliding and disintegrative flow failure. A highly developed commercial-industrial corridor, extending from the City of Kent to the Elliott Bay/Harbor Island marine terminal facilities, is founded on the young Holocene deposits of the Duwamish River valley. The deposits of this Holocene delta have been shaped not only by relative sea-level rise but also by episodic volcanism and seismicity. Ground-penetrating radar (GPR), cores, in situ testing, and outcrops are being used to examine the delta stratigraphy and to infer how these deposits will respond to future volcanic eruptions and earthquakes in the region. A geotechnical investigation of these river-mouth deposits indicates high initial liquefaction susceptibility during earthquakes, and possibly the potential for unlimited-strain disintegrative flow failure of the delta front. Posted: 2007-11-02
Open-File Report 2007-1232 : Seabed Ripple Morphology and Surficial Sediment Size at the SAX04 Experiments near Fort Walton Beach, Florida, Fall 2004 Introduction Data presented in this report originates from measurements obtained off the Florida coast (fig. 1) as part of the Sediment Acoustics Experiment (SAX04) and Ripples Department Research Initiative (DRI) (Office of Naval Research (ONR), Critical Benthic Environmental Processes and Modeling, Long Range BAA 04-001, Sept. 10, 2003). The aim of this document is to present methods employed to extract data and the resulting measured ripple characteristics (ripple height, wavelength, and orientation) and seabed grain sizes. Application and analysis of the data with respect to hydro- and morphodynamics will be addressed in subsequent reports. Sediment transport in the coastal region is a complex process involving interactions between flow dynamics, sediments, and bedforms. Sediment type and bed geometry directly influence entrainment of sediments into suspension, and at sites where ripples occur (sand formations on the order of several cm high and less than two meter long wavelengths), the understanding of ripple dynamics is an essential component in improving sediment transport models. To gain a better understanding and ability to predict sediment transport, a field study was undertaken to investigate morphology, orientation, and dynamics of ripples on the seafloor. The data obtained from the field campaign also supports an on-going effort to study the effects of ripples on low grazing acoustic penetration into sandy marine sediments for the detection of objects, such as mines (Jackson and others, 2002). Posted: 2007-11-01
Open-File Report 2007-1305: Bathymetry, Substrate and Circulation in Westcott Bay, San Juan Islands, Washington Nearshore bathymetry, substrate type, and circulation patterns in Westcott Bay, San Juan Islands, Washington, were mapped using two acoustic sonar systems, video and direct sampling of seafloor sediments. The goal of the project was to characterize nearshore habitat and conditions influencing eelgrass (Z. marina) where extensive loss has occurred since 1995. A principal hypothesis for the loss of eelgrass is a recent decrease in light availability for eelgrass growth due to increase in turbidity associated with either an increase in fine sedimentation or biological productivity within the bay. To explore sources for this fine sediment and turbidity, a dual-frequency Biosonics sonar operating at 200 and 430 kHz was used to map seafloor depth, morphology and vegetation along 69 linear kilometers of the bay. The higher frequency 430 kHz system also provided information on particulate concentrations in the water column. A boat-mounted 600 kHz RDI Acoustic Doppler Current Profiler (ADCP) was used to map current velocity and direction and water column backscatter intensity along another 29 km, with select measurements made to characterize variations in circulation with tides. An underwater video camera was deployed to ground-truth acoustic data. Seventy one sediment samples were collected to quantify sediment grain size distributions across Westcott Bay. Sediment samples were analyzed for grain size at the Western Coastal and Marine Geology Team sediment laboratory in Menlo Park, Calif. These data reveal that the seafloor near the entrance to Westcott Bay is rocky with a complex morphology and covered with dense and diverse benthic vegetation. Current velocities were also measured to be highest at the entrance and along a deep channel extending 1 km into the bay. The substrate is increasingly comprised of finer sediments with distance into Westcott Bay where current velocities are lower. This report describes the data collected and preliminary findings of USGS Cruise B-6-07-PS conducted between May 31, 2007 and June 5, 2007. Posted: 2007-10-18
Fact Sheet 2006-3111: Land-Based Lidar Mapping--a New Surveying Technique to Shed Light on Rapid Topographic Change The rate of natural change in such dynamic environments as rivers and coastlines can sometimes overwhelm the monitoring capacity of conventional surveying methods. In response to this limitation, USGS scientists are pioneering new applications of light detection and ranging (lidar), a laser-based scanning technology that promises to greatly increase our ability to track rapid topographic changes and manage their impact on affected communities. Posted: 2007-10-12
The Coastal Sedimentary System: Northern North Carolina The USGS, in collaboration with the State of North Carolina and university researchers, is studying the coastal sedimentary system of northern North Carolina. The primary objective is to map the regional sedimentary framework of the inner shelf in order to understand recent coastal processes, including erosion and the impacts of shoreline change. Posted: 2007-10-11
USGS Data Series 265, Time-Series Photographs of the Sea Floor in Western Massachusetts Bay, Version 1, 1989-1993, USGS Data Series 265, Title Page This U.S. Geological Survey (USGS) Data Series report presents time-series photographs of the sea floor obtained from an instrumented tripod deployed in western Massachusetts Bay (42° 22.6' N., 70° 47.0' W., 30 m water depth) from December 1989 to March 1990; July 1990 to October 1990; and October 1990 to February 1991. The objective of this report is to enable easy and rapid viewing of the photographs and to provide a medium-resolution digital archive. The images, obtained every 6 hours, are presented as a movie (in .avi format that may be viewed using an image viewer such as QuickTime or Windows Media Player) and as individual images (.jpg format.)" /> Posted: 2007-07-05
Florida Shelf Habitat (FLaSH) Map Project The FLaSH Map project is a multiagency approach to benthic habitat mapping. Existing data is presented via user-friendly graphic, geographic, and visualization tools. Data from multibeam, sidescan sonar imagery, still and video images, streaming resistivity, and sediment grabs are available for viewing by the general public, scientists and managers. Posted: 2007-06-18
Gulf of Mexico and Southeast Tidal Wetlands This project is investigating the loss of coastal wetlands and adjacent uplands in order to determine long-term change in wetlands and to provide a model for determining areas that are most vulnerable to loss because of combinations of human and natural impacts. Posted: 2007-06-01
Open-File Report 2007-1001: The Role of Aeolian Sediment in the Preservation of Archaeological Sites in the Colorado River Corridor, Grand Canyon, Arizona: Final Report on Research Activities, 2003-2006 This report summarizes a three-year study of aeolian sedimentary processes in the Colorado River corridor, Grand Canyon, Arizona, and discusses the relevance of those processes to the preservation of archaeological sites. Findings are based upon detailed sedimentary and geomorphic investigations conducted in three areas of the river corridor, continuous measurements of wind, precipitation, and aeolian sediment transport at six locations for up to 26 months, short-term field study at 35 other sites, examination of historical aerial photographs, and review of data collected and analyzed by previous studies. Detailed results of this study, which involved collaboration with scientists at the Grand Canyon Monitoring and Research Center, National Park Service, Northern Arizona University, the Hopi Tribe, and GeoArch, Inc., have been published previously in topical USGS Open-File Reports (Draut and Rubin, 2005, 2006), a USGS Scientific Investigations Report (Draut and others, 2005), and will be discussed in two forthcoming journal articles. This report serves as an overview of the results and contains new conclusions regarding aeolian sedimentary processes in the Colorado River Ecosystem and their relevance to many archaeological sites. Posted: 2007-03-20
Professional Paper 1605: Are North Slope Surface Alluvial Fans Pre-Holocene Relicts? The surface morphology of the northern slope of the Brooks Range (North Slope) from the Canning River, Alaska, eastward is dominated by a series of large alluvial fans and braided streams floored by coarse alluvium. On the basis of the absence of sediment on the seasonal sea ice after spring flooding, the measured stability of fan fronts during a 30-year period, and the scarcity or absence of Holocene marine sedimentary deposits seaward of the fans, we conclude that the fans are not prograding now nor have they been prograding at any time during the Holocene. In numerous areas, surficial fan alluvium terminates on land at or below 2-m-thick glaciomarine deposits. These deposits, the Flaxman Member of the Gubik Formation, formed during the latest major interglacial transgression (oxygen-isotope Stage 5a) at about 85-80 ka. We therefore believe that the fans are still older. Our observations suggest that during the latest transgression and the following sea level high stand, the North Slope depositional environment and climate differed greatly from the present ones. Posted: 2007-02-14
Open-File Report 2006-1318: Deschutes Estuary Feasibility Study; Hydrodynamics and Sediment Transport Modeling Continual sediment accumulation in Capitol Lake since the damming of the Deschutes River in 1951 has altered the initial morphology of the basin. As part of the Deschutes River Estuary Feasibility Study (DEFS), the USGS was tasked to model how tidal and storm processes will influence the river, lake and lower Budd Inlet should estuary restoration occur. Understanding these mechanisms will assist in developing a scientifically sound assessment on the feasibility of restoring the estuary. Posted: 2007-01-19
Data Series 182, 2006: usSEABED: Pacific Offshore Surficial-Sediment Data Release Over the past 50 years there has been an explosion in scientific interest, research effort, and information gathered on the geologic sedimentary character of the continental margin of the United States. Data and information from thousands of publications have greatly increased our scientific understanding of the geologic origins of the margin surface but rarely have those data been combined and integrated. This publication is the first release of the Pacific coast data from the usSEABED database. The report contains a compilation of published and unpublished sediment texture and other geologic data about the sea floor from diverse sources. usSEABED is an innovative database system developed to unify assorted data, with the data processed by the dbSEABED system. Examples of maps displaying attributes such as grain size and sediment color are included. This database contains information that is a scientific foundation for the U.S. Geological Survey (USGS) Seafloor Mapping and Benthic Habitats project and the Marine Aggregate Resources and Processes assessment project, and will be useful to the marine science community for other studies of the Pacific coast continental margin. Posted: 2006-12-01
Open-File Report 2006-1360 - Underwater Microscope for Measuring Spatial and Temporal Changes in Bed-Sediment Grain Size For more than a century, studies of sedimentology and sediment transport have measured bed-sediment grain size by collecting samples and transporting them back to the lab for grain-size analysis. This process is slow and expensive. Moreover, most sampling systems are not selective enough to sample only the surficial grains that interact with the flow; samples typically include sediment from at least a few centimeters beneath the bed surface. New hardware and software are available for in-situ measurement of grain size. The new technology permits rapid measurement of surficial bed sediment. Here we describe several systems we have deployed by boat, by hand, and by tripod in rivers, oceans, and on beaches. Posted: 2006-12-01
USGS Circular 1198 - Beyond the Golden Gate - Oceanography, Geology, Biology, and Environmental Issues in the Gulf of the Farallones The USGS began a major geologic and oceanographic study of the Gulf of the Farallones in 1989. This investigation, the first of several now being conducted adjacent to major population centers by the USGS, was undertaken to establish a scientific data base for an area of 3,400 square kilometers (1,000 square nautical miles) on the Continental Shelf adjacent to the San Francisco Bay region. The results of this study can be used to evaluate and monitor human impact on the marine environment. Posted: 2006-11-17
Open-File Report 2006-1346 - Swath Bathymetric Survey of Englebright Lake, Yuba-Nevada Counties, California USGS report presenting a bathymetric survey of Englebright Reservoir, located in the Sierra Nevada Foothills of California on the Yuba River. The survey was conducted in May, 2001, and this report presents calculations of volumes of sediment that have accumulated in the lake since dam construction in 1941. Posted: 2006-11-14
Open-File Report 2006-1293 - Reconnaissance Investigation of Caribbean Extreme Wave Deposits; Preliminary Observations, Interpretations, and Research Directions his report presents an overview of preliminary geological investigations and recommended future research activities in the Caribbean region pertaining to coastal hazards with an emphasis on establishing tsunami risk for U.S. territories. Fieldwork was conducted in March 2006 on the islands of Bonaire, Puerto Rico, and Guadeloupe to evaluate the stratigraphic records of extreme wave deposits as possible indicators of paleotsunami recurrence. Morphological, sedimentological, and stratigraphic evidence indicate that shore-parallel coral rubble deposits composed of coarse clasts and sand that are 10s of meters wide and several meters thick are depositional complexes that have accumulated for a few centuries or millennia, and are not entirely the result of one or a few tsunamis as previously reported. The origins of boulder fields on elevated rock platforms of the Caribbean islands are more complicated than the origins of ridge complexes because boulder fields can be constructed by either storm waves or tsunamis. What is needed now for more conclusive interpretations is a systematic sedimentological approach to deposit analysis and a set of criteria for distinguishing between coarse clast storm and tsunami deposits. Assembling more field data from other Caribbean islands, analyzing stratigraphic deposits on Puerto Rico and Bonaire, and investigating boulder field deposits resulting from a historical tsunami can accomplish this. Also needed are improved sediment transport models for coarse clasts that can be used to estimate the competence and capacity of tsunamis and storms waves and to determine whether a deposit likely was created by a tsunami or extreme storm. Improved models may also be useful for reconstructing the magnitude of extreme wave events. Posted: 2006-10-30
Maps Showing the Stratigraphic Framework of South Carolina's Long Bay from Little River to Winyah Bay South Carolina's Grand Strand is a heavily populated coastal region that supports a large tourism industry. Like most heavily developed coastal communities, the potential for property damage and lost revenues associated with coastal erosion and vulnerability to severe storms is of great concern. In response to these concerns, the US Geological Survey (USGS) and the South Carolina Sea Grant Consortium have chosen to focus upon the Grand Strand and immediately adjacent Long Bay as a portion of Phase II of the South Carolina/Georgia Coastal Erosion Study (SC/GCES). Posted: 2006-10-20
U.S. Geological Survey Open-File Report 03-221 This report contains descriptions and ancillary information for 62 bedrock cores, most with associated photographs, from western Cape Cod, Massachusetts. Posted: 2006-10-20
U.S. Geological Survey Open-File Report 2005-1001 Sediments off the eastern United States vary markedly in texture - the size, shape, and arrangement of their grains. For descriptive purposes, however, it is typically most useful to classify these sediments according to their grain-size distributions. Starting in 1962, the U.S. Geological Survey (USGS) and the Woods Hole Oceanographic Institution (WHOI) began a joint program to study the marine geology of the continental margin off the Atlantic coast of the United States. As part of this program and numerous subsequent projects, thousands of sediment samples were collected and analyzed for grain size. Posted: 2006-10-20
U.S. Geological Survey Fact Sheet 2005-3061 Predictions of the transport and long-term fate of particles in the coastal ocean are needed to address issues related to commerce, defense, public health, and the quality of the marine environment. For example, models can be used to investigate waste disposal and the transport and fate of contaminated materials; burial rates for naval mines or archaeological artifacts; water-column optical properties; transport and fate of biological particles; prediction of coastal flooding and coastal erosion; impacts of sea-level or wave-climate changes and coastal development; construction and maintenance of navigable waterways; habitat for commercial fisheries; impacts of natural or anthropogenic changes in coastal conditions on recreational activities; and design of intakes and outfalls for sewage treatment, cooling systems, and desalination plants. Posted: 2006-10-20
Sea Floor Topography and Backscatter Intensity of the Hudson Canyon Region Offshore of New York and New Jersey, USGS Open-File Report 2004-1441, Title Page This report (available on CD-ROM and on the internet) presents maps of the sea-floor topography and backscatter intensity of the Hudson Canyon region, offshore of New York and New Jersey, USA at a scale of 1:300,000. The maps and geologic interpretation are presented on two sheets in PDF format. Sheet 1 shows sea floor topography as shaded relief. Sheet 2 shows sea floor topography as shaded relief with backscatter intensity superimposed in color. Sheet 1 also contains interpretive text, and both sheets contain figures and tables that further present and describe the data. The interpretive tex can also be viewed in html with links to the figures and tables on the map sheets. The maps are based on new multibeam echo-sounder data collected on an 18-day cruise carried out aboard the National Oceanic and Atmospheric Administration (NOAA) Ship Ronald H. Brown in 2002. Posted: 2006-10-20
U.S. Geological Survey Open-File Report 2004-1435, title page Geophysical analysis of a high-amplitude, negative polarity reflector in the Baltimore Canyon Trough are compatible with it being an autochthonous Aalenian(?) salt lens. Posted: 2006-10-20
USGS OFR 02-372, Physical Properties of Long Island Sound Sediment Cores, Title Page This report presents data on x-radiography, water content, and sediment texture from sediment cores collected in 1996 in Long Island Sound, offshore of Connecticut and New York (Figure 1). Core locations and analytical data are presented in both graphical and numerical form. The physical properties data presented here are a subset of a larger dataset consisting of results from these cores and other sediment samples. (See Poppe and others (1998) and Mecray and others (2000) for samples collected in Long Island Sound from 1996-2001 by the USGS.) Posted: 2006-10-20
USGS OFR 2005-1145: Interpolation of Reconnaissance Multibeam Bathymetry from North-Central Long Island Sound, Title Page This data report contains both the original reconnaissance bathymetry collected during NOAA surveys H11043, H11044, H11045 of north-central Long Island Sound, and interpolated grids and color-encoded hill-shaded imagery produced from the reconnaissance. The report was produced because these bathymetric grids and imagery help define the geological variability of the sea floor, improve our understanding of surficial processes, and provide a detailed framework for future research, monitoring, and management activities. Posted: 2006-10-20
Scientific Investigations Map 2944: Sand Waves at the Mouth of San Francisco Bay, California A multibeam bathymetric survey that produced unprecedented high resolution images of the mouth of San Francisco Bay was conducted in 2004 and 2005. The survey, performed over forty-four days by the Seafloor Mapping Lab at California State University, Monterey Bay, consisted of 1,138 track lines, 1.1 billion soundings, and covered an area of 154 sq. km (60 sq.mi). The goals of this survey were to analyze sediment transport pathways at the mouth of San Francisco Bay and to calculate bathymetric change since the last survey was completed in 1956. The survey showed that significant bathymetric changes have occurred over the past 50 years. It also revealed that the study area contains sand waves that are among the largest and bedform morphologies that are among the most varied in the world. This set of five sheets shows views of the sand waves on the seafloor from different perspectives along with descriptive text. Posted: 2006-10-17
Open-File Report 2006-1262: A History of Intertidal Flat Area in South San Francisco Bay, California; 1858 to 2005 A key question in salt pond restoration in South San Francisco Bay is whether sediment sinks created by opening ponds will result in the loss of intertidal flats. Analyses of a series of bathymetric surveys of South San Francisco Bay made from 1858 to 2005 reveal changes in intertidal flat area in both space and time that can be used to better understand the pre-restoration system. This analysis also documents baseline conditions of intertidal flats that may be altered by restoration efforts... Improved understanding of sediment input to South San Francisco Bay, especially from Central Bay, how it is likely to change in the future, the redistribution of sediment within the bay, and ultimately its effect on intertidal flat area would aid in the management of restoration of South San Francisco Bay salt ponds. Posted: 2006-10-16
Open-File Report 2006-1287 - Sediment Deposition and Erosion in South San Francisco Bay, California from 1956 to 2005 Sediment deposition and erosion in South San Francisco Bay from 1956 to 2005 was studied by comparing bathymetric surveys made in 1956, 1983, and 2005. From 1956 to 1983, the region was erosional. In contrast, from 1983 to 2005, the region was depositional. Analysis of subregions defined by depth, morphology and location revealed similarities in behavior during both the erosional and depositional periods. During the entire period of the study, there was net erosion in the shallows (<1 m depth) on the eastern shore of the bay north of the Dumbarton Bridge and net deposition in the region south of Dumbarton Bridge. The rates, however, reflected the sediment regime of each time period. Erosional areas were less erosional during the period with net deposition and depositional zones were more depositional. The cause for the increase in deposition from 1983 to 2005 is unknown, but could be related to an increase in sediment supply from Central Bay. The patterns of deposition and erosion and the change in rates are consistent with an increase in sediment supply from the north, as would occur if the supply from Central Bay increased from 1956-1983 to 1983-2005. Additional research is needed to fully understand why South San Francisco Bay became depositional from 1983 to 2005 and to determine the implications of this change to the planned salt pond restoration in the region. Posted: 2006-10-16
Open-File Report 2006-1125: Coastal Circulation and Sediment Dynamics in Hanalei Bay, Kaua'i, Hawaii, Part II, Tracking Recent Fluvial Sedimentation; Isotope Stratigraphy Obtained in Summer 2005 Delivery and dispersal of fluvial sediment in Hanalei Bay, Kaua’i, Hawaii, have important implications for the health of local coral reefs. The reef community in Hanalei Bay represents a relatively healthy ecosystem. However, the reefs are periodically stressed by storm waves, and increases in sediment and dissolved substances from the Hanalei River have the potential to cause additional stress. Increased turbidity and sedimentation on corals during Hanalei River floods that occur in seasons of low wave energy, when sediment would not be readily remobilized and advected out of the bay, could affect the health and sustainability of coral reefs and the many associated species. Posted: 2006-08-04
usSEABED: East Coast Offshore Surficial Sediment Data Release, Title Page Over the past 50 years there has been an explosion in scientific interest, research effort and information gathered on the geologic sedimentary character of the U.S. Atlantic coast continental margin. Data and information from thousands of publications have greatly increased our scientific understanding of the geologic origins of the shelf surface but rarely have those data been combined and integrated. This publication is the first release of the Atlantic coast data from the usSEABED database. The report contains a compilation of published and unpublished sediment texture and other geologic data about the seafloor from diverse sources. usSEABED is an innovative database system developed to bring assorted data together in a unified database. The dbSEABED system is used to process the data. Examples of maps displaying attributes such as grain size and sediment color are included. This database contains information that is the scientific foundation for the USGS Marine Aggregate Resources and Processes Assessment and Benthic Habitats projects and will be useful to the marine science community for other studies of the Atlantic coast continental margin. The publication is divided into ten sections: Home, Introduction, Contents, usSEABED (data), dbSEABED (processing), Data Catalog, References, Contacts, Acknowledgments, and Frequently Asked Questions. Use the navigation bar on the left to navigate to specific sections of this report. Underlined topics throughout the publication are links to more information. Links to specific and detailed information on processing and those to pages outside this report will open in a new browser window. Posted: 2006-08-03
Open-File Report 2006-1188: Measurements of Wind, Aeolian Sand Transport, and Precipitation in the Colorado River Corridor, Grand Canyon, Arizona; January 2005 to January 2006 This report presents measurements of aeolian sediment-transport rates, wind speed and direction, and precipitation records from six locations that contain aeolian deposits in the Colorado River corridor through Grand Canyon, Grand Canyon National Park, Arizona. Aeolian deposits, many of which contain and preserve archaeological material, are an important part of the Grand Canyon ecosystem. This report contains data collected between January 2005 and January 2006, and is the second in a series; the first contained data that were collected between November 2003 and December 2004. Posted: 2006-07-27
Scientific Investigations Map 2917: Under the Golden Gate Bridge - Views of the Sea Floor Near the Entrance to San Francisco Bay, California San Francisco Bay in Northern California is one of the largest and most altered estuaries within the United States. The sea floor within the bay as well as at its entrance is constantly changing due to strong tidal currents, aggregate mining, dredge disposal, and the creation of new land using artificial fill. Understanding this dynamic sea floor is critical for addressing local environmental issues, which include defining pollution transport pathways, deciphering tectonics, and identifying benthic habitats. Mapping commercial interests such as safe ship navigation and dredge disposal is also significantly aided by such understanding. Over the past decade, the U.S. Geological Survey (USGS), the National Oceanic and Atmospheric Administration (NOAA), and California State University, Monterey Bay (CSUMB) in cooperation with the U.S. Army Corps of Engineers (USACOE) and the Center for Integrative Coastal Observation, Research and Education (CICORE) have partnered to map central San Francisco Bay and its entrance under the Golden Gate Bridge using multibeam echosounders. These sonar systems can continuously map to produce 100 percent coverage of the sea floor at meter-scale resolution and thus produce an unprecedented view of the floor of the bay. This poster shows views of the sea floor in west-central San Francisco Bay around Alcatraz and Angel Islands, underneath the Golden Gate Bridge, and through its entrance from the Pacific Ocean. The sea floor is portrayed as a shaded relief surface generated from the multibeam data color-coded for depth from light blues for the shallowest values to purples for the deepest. The land regions are portrayed by USGS digital orthophotographs (DOQs) overlaid on USGS digital elevation models (DEMs). The water depths have a 4x vertical exaggeration while the land areas have a 2x vertical exaggeration. Posted: 2006-07-07
Coasts of Colombia Due to the complex geologic history of the northwestern part of South America, the Colombian coasts include a variety of coastline types, ranging from high-relief, steep-plunging cliffs typical of igneous and metamorphic massifs, to low, sandy barrier islands and extensive mangrove swamps characteristic of deltaic areas of both coasts. Posted: 2006-06-14
Data Series 180, 2006: Capitol Lake, Washington, 2004 Data Summary At the request of the Washington Department of Ecology (WDOE), the US Geological Survey (USGS) collected bathymetry data in Capital Lake, Olympia, Wash., on September 21, 2004. The data are to be used to calculate sediment infilling rates within the lake as well as for developing the bottom boundary conditions for numerical models of water quality, sediment transport, and morphological change. In addition, the USGS collected sediment samples in Capitol Lake in February, 2005, to help characterize bottom sediment for numerical model calculations and substrate assessment. Posted: 2006-05-23
Coastal Classification Mapping Project A Coastal Classification Map describing local geomorphic features is the first step toward determining the hazard vulnerability of an area. The Coastal Classification Map series of the National Assessment of Coastal Change Project presents ground conditions such as beach width, dune elevations, overwash potential, and density of development. In order to complete a hazard vulnerability assessment, that information must be integrated with other information, such as prior storm impacts and beach stability. Posted: 2006-05-02
Open-File Report 2006-1036: Quantitative X-ray Diffraction Mineralogy of Los Angeles Basin Core Samples This report contains X-ray diffraction (XRD) analysis of mineralogy for 81 sediment samples from cores taken from three drill holes in the Los Angeles Basin in 2000-2001. We analyzed 26 samples from Pier F core, 29 from Pier C core, and 26 from the Webster core. These three sites provide an offshore-onshore record across the Southern California coastal zone. This report is designed to be a data repository; these data will be used in further studies, including geochemical modeling as part of the CABRILLO project. Summary tables quantify the major mineral groups, whereas detailed mineralogy is presented in three appendices. The rationale, methodology, and techniques are described in the following paper. Posted: 2006-02-23
USGS WCMG - Notes from the field... Sumatra 2005 News and Information about the USGS West Sumatra International Tsunami Survey Team's Field Study, March 30 - April 26, 2005. These "Notes from the field" pages were created on a daily basis as a way to report findings during the ITST's field study. The effort began just as the 28 March 2005 earthquake and tsunami occurred off Sumatra. Posted: 2005-05-02
Scientific Investigations Report 2004-5183: Late Quaternary Deposition in the Inner Basins of the California Continental Borderland- Part A. Santa Monica Basin Radiocarbon dating of sediment core samples from Santa Monica Basin document Holocene (younger than approximately 11 ka) landslides and fault offsets along the basin margin. The new dates include 17 from six piston cores on the continental slope and 11 from Ocean Drilling Program Site 1015 on the basin floor. The dates, which are based on data from pelagic and benthic foraminifera in addition to several dates from mollusk shells, are used to provide chronostratigraphic control for a previously determined basin-wide seismic stratigraphy. The geologic setting at the core sites and a sediment log for each core are shown. In addition, each sediment log is accompanied by a color core photograph as well as P-wave velocity and gamma-ray density profiles. The primary purpose of the report is to make the radiocarbon dates available for other studies in the Santa Monica Basin. A comparison of sediment accumulation rates between the late Pleistocene and Holocene provides insight to the effects of sea-level change on sediment input to the basin. In addition, the results can be used to evaluate the effectiveness of wire-line piston coring in providing age control for earthquake hazard and sedimentologic studies. Posted: 2005-02-15
Tsunamis and Earthquakes - 2005 Sri Lanka Tsunami Study - USGS WCMG USGS Western Coastal and Marine Geology was part of an international team that studied sediment deposits in Sri Lanka from the tsunami generated by the magnitude 9.0 Sumatra earthquake on December 26, 2004 Posted: 2005-02-14
Marine Aggregate Resources and Processes The Marine Aggregates (Sand and Gravel Assessment) Project has developed and is implementing a scientifically rigorous series of regional studies mapping the seafloor sedimentary character and assessing marine sand and gravel resources around the United States. Results of the regional assessments will ultimately comprise a national assessment of marine sand and gravel. This study is responding to increasing demand for web-accessible GIS-type data and interpreted geologic map information on the sedimentary character of the seafloor and aggregate resources suitable for beach nourishment and coastal restoration, as well as seafloor sediment texture information for benthic habitat mapping and sediment transport studies. Posted: 2004-05-07
Contaminant Transport in Massachusetts Bay Contaminants have accumulated in sediments of many coastal environments of the United States, particularly those near major metropolitan centers. U.S. Geological Survey scientists provide information about the distribution, severity, and fate of these contaminated sediments that is essential for making informed management decisions about multiple uses of these coastal environments. Posted: 2004-03-02
Metal Concentrations in Sediments of Boston Harbor and Massachusetts Bay Document Environmental Change - USGS Fact Sheet 150-97 Over the last decade, contaminants entering Boston Harbor have been significantly reduced. Although parts of the harbor still contain metals at concentrations above toxicity guidelines for bottom-dwelling animals, we have observed decreasing metal concentrations over time that are encouraging. We are learning which natural sedimentary processes significantly influence the fate and transport of metals in Boston Harbor and Massachusetts Bay. Posted: 2004-03-02
Predicting the Long-Term Fate of Sediments and Contaminants in Massachusetts Bay - USGS Fact Sheet 172-97 Contaminants have accumulated in the sediments of Massachusetts Bay, typical of many coastal areas near major metropolitan centers that have been used for waste disposal since colonial times. Developing an understanding of where and why contaminants accumulate is essential for making informed management decisions about uses of these coastal areas and for developing sound strategies for monitoring environmental change. Posted: 2004-03-02
Sedimentary Environments in Long Island Sound: A Guide to Sea-Floor Management in a Large Urbanized Estuary - USGS Fact Sheet 041-98 Bottom sedimentary environments, defined by sidescan-sonar patterns, indicate where sea-floor sediments are moved and deposited in the Long Island Sound estuary. The patchy distribution of environments, which reflects both regional and local changes in geologic and oceanographic conditions, provides a predictive framework for those concerned with the management and utilization of the sea floor in this urbanized area. Posted: 2004-03-02
The Chesapeake Bay Bolide Impact: A New View of Coastal Plain Evolution - USGS Fact Sheet 049-98 A spectacular geological event took place on the Atlantic margin of North America about 35 million years ago in the late part of the Eocene Epoch. Sea level was unusually high everywhere on Earth, and the ancient shoreline of the Virginia region was somewhere in the vicinity of where Richmond is today. Tropical rain forests covered the slopes of the Appalachians. To the east of a narrow coastal plain, a broad, lime (calcium carbonate)-covered continental shelf lay beneath the ocean. Suddenly, with an intense flash of light, that tranquil scene was transformed into a hellish cauldron of mass destruction. From the far reaches of space, a bolide (comet or asteroid), 3-5 kilometers in diameter, swooped through the Earth's atmosphere and blasted an enormous crater into the continental shelf. The crater is now approximately 200 km southeast of Washington, D.C., and is buried 300-500 meters beneath the southern part of Chesapeake Bay and the peninsulas of southeastern Virginia. Posted: 2004-03-02
Antarctica - The Dynamic Heart of It All - USGS Fact Sheet The U.S. Geological Survey (USGS) has worked in Antarctica for nearly 50 years, starting in 1947 with geophysical and geologic surveys and in 1957 with topographic mapping. Today the USGS also does marine, airborne, and satellite studies, as well as mapping and coring of the ice sheet, as part of the U.S. Antarctic Program. USGS scientific leadership is a cornerstone for international Antarctic cooperation, and data and information gathered by USGS researchers are important to the development of U.S. policy regarding the Antarctic. Posted: 2004-03-02
Coastal Erosion of Southern Lake Michigan - USGS Fact Sheet Geological Survey studies the geologic processes at work in the Great Lakes region because they have direct bearing on the use, management, development, and preservation of the shoreline. It is important to understand how these processes shape our daily lives. About 15 percent of the United States' and 50 percent of Canada's population live along or near the 9,000-kilometer-long coastline of the Great Lakes. About 83 percent of the shoreline is privately-owned with property values as high as $10,000 per linear foot of lakefront. Posted: 2004-03-02
Coastal Wetlands and Sediments of the San Francisco Bay System - USGS Fact Sheet San Francisco Bay has received much scientific attention over the years primarily because of regional questions regarding water quality and, more recently, geologic hazards, but very little is known about sediment distribution and movement on the floor of the Bay. The link between sediment accumulation in the Bay and processes that produce the staggering losses of wetlands acreage and continual channel filling is becoming better understood as U.S. Geological Survey scientists undertake new research of the region. Posted: 2004-03-02
Crater Lake National Park: Presently Tranquil - USGS Fact Sheet Are volcanic eruptions likely again at Crater Lake? One of the approaches U.S. Geological Survey scientists are using to answer this important question is to unravel the geologic history of the Crater Lake caldera floor. Posted: 2004-03-02
Effects of Major Storms on Pacific Islands - USGS Fact Sheet Tropical storms of various kinds are as much a depositional event as an erosional event. Much attention is given to the destructive aspects of major storms because of the loss of life and property, but little is known about their beneficial effects to coastal accretion. While we can usually measure and map the instantaneous effects of a tropical storm, we can only speculate about the long-term effects. Geologic mapping by the U.S. Geological Survey in areas prone to storm effects can give us opportunities to minimize losses by identifying locations most likely to suffer. Posted: 2004-03-02
The Escanaba Trough of Gorda Ridge: A Laboratory for Mineral-forming Processes
- USGS Fact Sheet The Gorda Ridge is a unique geological system in the Exclusive Economic Zone of the United States. This tectonically and volcanically active plate boundary has an unusual morphology for spreading centers in the Pacific Ocean: a deep, wide axial valley flanked by high ridges. Because of its location near the continental margin, part of the axial valley known as the Escanaba Trough is covered by sediment. The Escanaba Trough provides opportunities for scientists to learn details about tectonics, volcanism, mineral formation, and biological activity that are not normally observed at mid-ocean ridges. It is a geological laboratory of grand proportions. Posted: 2004-03-02
Evolution and History of Incised Valleys: The Mobile Bay Model - USGS Fact Sheet Incised valleys along the Gulf coast commonly result from rivers eroding rapidly in response to a fall in sea level. As sea level rises, sediments fill incised valleys and form nearshore elongated sandbodies such as barrier islands. These sandbodies can be potential sites for hard-mineral accumulations and are modern analogues to buried sands in the ancient rock record with high potential of being oil and gas reservoirs. Processes that formed residual sediment accumulations may also help to predict the outcome of man's erosion mitigation and wetland nourishment efforts. Today, the geologic imprint of incised valleys across the continental shelf provides evidence of sea-level change over the past 18,000 years. Posted: 2004-03-02
Gas (Methane) Hydrates -- A New Frontier - USGS Fact Sheet Methane trapped in marine sediments as a hydrate represents such an immense carbon reservoir that it must be considered a dominant factor in estimating unconventional energy resources; the role of methane as a 'greenhouse' gas also must be carefully assessed. Posted: 2004-03-02
Geology and the Fishery of Georges Bank - USGS Fact Sheet A comprehensive knowledge of the geological environment is required to answer questions regarding the health of a fishery, the effects of ocean dumping and pollutant dispersal, and the impact of energy exploration activities. Posted: 2004-03-02
Geology of the Gulf of the Farallones National Marine Sanctuary - USGS Fact Sheet The geology and oceanography of the Farallones and surrounding area is atypical and complex. These factors complicate the process of understanding the environmental effects of man's influence such as the disposal of dredge spoils and radioactive wastes. Our goal is to assemble, in a non-crisis mode, geological information to support sound management decisions for any purpose. Posted: 2004-03-02
High-Energy Storms Shape Puerto Rico - USGS Fact Sheet Geologists have known for many years that damage inflicted by hurricanes on coastal areas may be less important for the long-term evolution of a coast than the effects of less intense, but more frequent, storm events. Indeed, high-energy storms may be needed to maintain the health of delicate marine ecologies in the coastal environment. Marine geologists of the U.S. Geological Survey working in Puerto Rico are confident that the long-term effects of Hurricane Hugo on the coastal environment are minimal, though the economic damage was significant. Detailed oceanographic studies are needed to define the sediment budget of the nearshore areas of Puerto Rico and to provide baseline information for studying storm effects. Posted: 2004-03-02
Hurricane Impacts on the Coastal Environment - USGS Fact Sheet In terms of insured losses, Hurricane Andrew is the most severe catastrophe in the Nation history. Prior to the arrival of Andrew, the U.S. Geological Survey (USGS), in cooperation with the Louisiana Geological Survey (LGS), acquired an extensive body of information and data on the behavior and long-term erosion of Louisiana barrier islands. As a result, we have a clear understanding of pre-storm conditions in this area; Andrew provided an opportunity to learn in detail the impact of a very large storm on Louisiana coastal environment. Posted: 2004-03-02
Investigating Climate Change of Western North America - USGS Fact Sheet The strength and position of the California Current drives the climate of the western United States. When global climate changed, the California Current should have been affected in such a way that evidence of change should be seen in 'proxy' data. If we can see how oceans respond to climate change, we can then infer how the atmosphere has reacted through time. The U.S. Geological Survey is examining a variety of proxy data from western North America and the eastern North Pacific Ocean that might give climate models added validity. Posted: 2004-03-02
Lake Baikal - A Touchstone for Global Change and Rift Studies - USGS Fact Sheet The Lake Baikal rift system is a modern analogue for formation of ancient Atlantic-type continental margins. It tells us the first chapter in the story of how continents separate and ultimately develop into ocean basins like the Atlantic Ocean. Posted: 2004-03-02
The Lake Pontchartrain Basin: Louisiana's Troubled Urban Estuary - USGS Fact Sheet Scientific studies recently begun by the U.S. Geological Survey suggest that several key natural processes and human-induced environmental factors are directly affecting the health of the Lake Pontchartrain Basin, one of America's largest estuaries. An increased knowledge of the critical geologic and estuarine processes affecting the Basin is essential for its management, improving environmental conditions, and mitigating future problems in the region. Such baseline information is of immediate value to planners and decision makers involved in the task of reversing the Basin's environmental degradation and restoring its water and habitat qualities. Posted: 2004-03-02
The Legacy of Contaminated Sediments in Boston Harbor - USGS Fact Sheet Contamination of sediments in Boston Harbor, particularly by metals, is so widespread that its effects may be felt long after the sources of contamination are shut off. Where are toxic concentrations of metals located today? How did they get there? How will they move? These are questions that must be answered in detail before we can properly estimate risk in the environment. Posted: 2004-03-02
Monterey Bay Marine Sanctuary Geological Processes and Framework - USGS Fact Sheet The U.S. Geological Survey (USGS) will move its Pacific Marine Geology program to a new location at the University of California at Santa Cruz (UCSC) and we are excited about our role in the marine sciences community around Monterey Bay. There is much to learn in the region, not only as a result of new opportunities in the Marine Sanctuary, but also that knowledge gained here may be transferred to our studies of similar environments in other parts of the world. Posted: 2004-03-02
Sand and Gravel Resources of Puerto Rico - USGS Fact Sheet The sand and gravel resources of Puerto Rico contribute significantly to the economy of the island as they are crucial ingredients in construction and recreation. Despite newly-imposed regulations prohibiting mining of beach sands, the strength of the associated underground economy is sufficiently strong to limit enforcement of the regulations. Consequently, beaches are eroding quickly causing significant damage to the environment and delicate ecosystems. New resources of sand and gravel would allow beaches to be nourished and construction activities to be supplied. Posted: 2004-03-02
Seafloor Images Refine Petroleum Exploration Models - USGS Fact Sheet GLORIA mapping has shown that we need to think again about our conventional models for formation of deep-sea fans. Exploration for hydrocarbon accumulations in ancient fan environments may change dramatically as a consequence of our new understanding of deep-sea fan formation. Posted: 2004-03-02
Seafloor Studies of Mamala Bay, Honolulu, Hawaii: USGS Fact Sheet Disposal of dredge spoils in the near offshore area, coupled with the rapid growth of Honolulu and other nearby municipalities, has placed increased stress on the environment of Mamala Bay. No satisfactory bathymetric map of the seafloor had existed, and little information has been compiled about the effects of these activities to determine whether modifications to the operation and management of the designated dump sites and sewage outfall locations were necessary. Posted: 2004-01-04
USGS OFR 03-111 - Preliminary Analysis Of Cores From North San Francisco Bay, California In March 2000, the U.S. Geological Survey collected sediment cores in North San Francisco Bay, California to determine the location of mercury-contaminated hydraulic mining debris. This report documents preliminary analyses conducted on a subset of the cores collected on the March 2000 cruise. Field and laboratory methods used to analyze the cores are described. Field core descriptions, core X-radiographs, classification of stratigraphy from X- radiographs, and magnetic susceptibility are presented in the data section. Posted: 2003-10-29
USGS OFR 03-250 - Bed-Sediment Grain-Size and Morphologic Data from Suisun, Grizzly, and Honker Bays, CA, 1998-2002 The USGS Place Based Studies Program for San Francisco Bay investigates this sensitive estuarine system to aid in resource management. As part of the inter-disciplinary research program, the USGS collected side-scan sonar data and bed-sediment samples from north San Francisco Bay to characterize bed-sediment texture and investigate temporal trends in sedimentation. The study area is located in central California and consists of Suisun Bay, and Grizzly and Honker Bays, sub-embayments of Suisun Bay. During the study (1998-2002), the USGS collected three side-scan sonar data sets and approximately 300 sediment samples. The side-scan data revealed predominantly fine-grained material on the bayfloor. We also mapped five different bottom types from the data set, categorized as featureless, furrows, sand waves, machine-made, and miscellaneous. We performed detailed grain-size and statistical analyses on the sediment samples. Overall, we found that grain size ranged from clay to fine sand, with the coarsest material in the channels and finer material located in the shallow bays. Grain-size analyses revealed high spatial variability in size distributions in the channel areas. In contrast, the shallow regions exhibited low spatial variability and consistent sediment size over time. Posted: 2003-10-29
USGS OFR 03-265 - Grand Canyon Riverbed Sediment Changes, Experimental Release of September 2000 - A Sample Data Set An experimental water release from the Glen Canyon Dam into the Colorado River above Grand Canyon was conducted in September 2000 by the U.S. Bureau of Reclamation. The U.S. Geological Survey (USGS) conducted sidescan sonar surveys between Glen Canyon Dam (mile -15) and Diamond Creek (mile 220), Arizona (mile designations after Stevens, 1998) to determine the sediment characteristics of the Colorado River bed before and after the release. The first survey (R3-00-GC, 28 Aug to 5 Sep 2000) was conducted before the release when the river was at its Low Summer Steady Flow (LSSF) of 8,000 cfs. The second survey (R4-00-GC, 10 to 18 Sep 2000) was conducted immediately after the September 2000 experimental release when the average daily flow was as high as 30,800 cfs as measured below Glen Canyon Dam (Figure 2). Riverbed sediment properties interpreted from the sidescan sonar images include sediment type and sandwaves; overall changes in these properties between the two surveys were calculated. Posted: 2003-10-29
USGS OFR 03-383 - Bathymetric and geophysical surveys of Englebright Lake, Yuba-Nevada Counties, California Harry L. Englebright Lake (Englebright Lake; Figure 1) is a 9-mile-long (14-kilometer) reservoir located in the Sierra Nevada foothills of northern California on the Yuba River gorge known as The Narrows. The reservoir is impounded by Englebright Dam (Photo 1), a concrete arch structure spanning 348 meters (1,142 feet) across and 79 meters (260 feet) high. The dam was constructed in 1941 for the primary purpose of trapping sediment derived from anticipated hydraulic mining operations in the Yuba River watershed. Hydraulic mining in the Sierra Nevada was halted in 1884 but resumed on a limited basis until the 1930's under the regulation of the California Debris Commission. Although no hydraulic mining in the upper Yuba River watershed resumed after the construction of the dam, the historical mine sites continued to contribute sediment to the river. Today, Englebright Lake is used primarily for recreation and hydropower. In 2001 and 2002, the U.S. Geological Survey (USGS) conducted bathymetric, geophysical, and geological studies of the reservoir under the auspices of the Upper Yuba River Studies Program (UYRSP), a multi-disciplinary investigation into the feasibility of introducing anadromous fish species to the Yuba River system upstream of Englebright Dam. A primary purpose of these studies was to assess the quantity and nature of the sediment that has accumulated behind the dam over the past 60 years. This report presents the results of those surveys, including a new bathymetric map of the reservoir and estimates of the total accumulated sediment volume. Posted: 2003-10-29
USGS OFR 03-397 - Preliminary Cross Section of Englebright Lake Sediments The Upper Yuba River Studies Program is a CALFED-funded, multidisciplinary investigation of the feasibility of introducing anadromous fish species to the Yuba River system upstream of Englebright Dam. Englebright Lake (Figure 1 on poster) is a narrow, 14-km-long reservoir located in the northern Sierra Nevada, northeast of Marysville, CA. The dam was completed in 1941 for the primary purpose of trapping sediment derived from mining operations in the Yuba River watershed. Possible management scenarios include lowering or removing Englebright Dam, which could cause the release of stored sediments and associated contaminants, such as mercury used extensively in 19th-century hydraulic gold mining. Transport of released sediment to downstream areas could increase existing problems including flooding and mercury bioaccumulation in sport fish. To characterize the extent, grain size, and chemistry of this sediment, a coring campaign was done in Englebright Lake in May and June 2002. More than twenty holes were drilled at 7 different locations along the longitudinal axis of the reservoir (Figure 4 on poster), recovering 6 complete sequences of post-reservoir deposition and progradation. Here, a longitudinal cross section of Englebright Lake is presented (Figure 5 on poster), including pre-dam and present-day topographic profiles, and sedimentologic sections for each coring site. This figure shows the deltaic form of the reservoir deposit, with a thick upper section consisting of sand and gravel overlying silt, a steep front, and a thinner lower section dominated by silt. The methodologies used to create the reservoir cross section are discussed in the lower part of this poster. Posted: 2003-10-29
USGS Fact Sheet 155-02 - Tracking Contaminants in Santa Monica Bay, Offshore of Greater Los Angeles Santa Monica Bay is a major recreational and commercial resource for the Greater Los Angeles region. Industrialization and the dramatic increase of population in the region over the past 100 years have strained the bay’s resources and polluted its sediments. To help evaluate any possible hazards posed by contamination, scientists from the U.S. Geological Survey (USGS) and local cooperating organizations are studying the processes that modify, transport, and redeposit sediments within Santa Monica Bay. Posted: 2003-10-29
Continental Shelf Research 22:6-7 - Sedimentation Processes, DDT, and the Palos Verdes margin The 14 papers of this volume can be divided into three categories: (1) mapping the extent and character of the deposit, (2) measuring the factors that cause the deposit to change with time and modeling that change, and (3) determining the effect of the deposit on the chemical and biological environment. Posted: 2003-10-29
An Overview of Coastal Land Loss: With Emphasis on the Southeastern United States In states bordering the Gulf of Mexico and the Atlantic Ocean, vast areas of coastal land have been destroyed since the mid 1800s as a result of natural processes and human activities. The physical factors that have the greatest influence on coastal land loss are reductions in sediment supply, relative sea level rise, and frequent storms, whereas the most important human activities are sediment excavation, river modification, and coastal construction. As a result of these agents and activities, coastal land loss is manifested most commonly as beach/bluff erosion and coastal submergence. Posted: 2003-08-20
U.S. Geological Survey Open-File Report 03-001, Title Page This report contains surficial sediment data from previously unpublished data sources or from gray literature. These data have been compiled as part of the National Benthic Habitats and Marine Aggregate Resources and Processes Projects to update the existent maps on surficial sediment distribution available for the Gulf of Maine region. Sediment data in this report are GIS ready and are broken into data layers by their original source project. The data layers are provided as single-point vector datasets with sample identifiers, navigation, textural attribute information, and FGDC compliant metadata. Posted: 2003-08-14
A Summary of Findings of the West-Central Florida Coastal Studies Project This report summarizes the major findings of the West-Central Florida Coastal Studies Project which was funded by the United States Geological Survey. This project was a co-operative five-year venture designed to conduct a geologic framework study of a barrier-island coastline and its adjacent inner continental shelf off west-central Florida. Posted: 2003-07-24
U.S. Coral Reefs—Imperiled National Treasures | USGS Fact Sheet 025-02 Coral reefs are home to 25% of all marine species. However, the tiny colonial animals that build these intricate limestone masses are dying at alarming rates. If this trend continues, in 20 years the living corals on many of the world’s reefs will be dead and the ecosystems that depend on them severely damaged. As part of the effort to protect our Nation’s extensive reefs, U.S. Geological Survey (USGS) scientists are working to better understand the processes that affect the health of these ecologically and economically important ecosystems. Posted: 2003-03-18
New Mapping Techniques Help Assess the Health of Hawai'i's Coral Reefs
| USGS Fact Sheet 084-01 More than 60% of coral reefs in U.S. waters are found in the extended Hawaiian Island chain. These complex and diverse marine ecosystems are not only ecologically important but also provide hundreds of millions of dollars annually to Hawai‘i’s economy. Elsewhere in the world, corals are dying at unprecedented rates, and the reefs of Hawai‘i may also be at risk. To monitor and protect these reefs and to help understand what is threatening coral-reef habitats worldwide, U.S. Geological Survey (USGS) and other scientists are using new techniques to create detailed maps of Hawai‘i’s coral reefs. Posted: 2003-03-18
Fact Sheet 020-98: Popular Beach Disappears Underwater in Huge Coastal Landslide--Sleeping Bear Dunes, Michigan In February 1995, a 1,600-foot stretch of popular beach at Sleeping Bear Dunes National Lakeshore suddenly slid into the waters of northeastern Lake Michigan. The National Park Service (NPS) immediately requested the assistance of the U.S. Geological Survey (USGS) in evaluating the hazard at the lakeshore. To protect the public, USGS and NPS scientists are conducting studies that will help predict when the landslide-prone area will move again Posted: 2003-03-18
Open-File Report 01-077: Clay Mineral Content of Continental Shelf and River Sediments, Southern California This report presents the clay mineral contents of the less than 2 micron size fraction of surface sediments from the continental shelf off Southern California, core samples from Santa Monica Bay, and bottom and suspended sediment samples from adjacent rivers draining Southern California. Clay minerals were determined using X-ray diffraction and the semiquantitative contents of smectite, illite, and chlorite plus kaolinite were calculated. Posted: 2003-03-18
Subsurface Controls on Historical Subsidence Rates and Associated
Wetland Loss in Southcentral Louisiana The Gulf Coast Basin is a region where subsidence and fault activation are common around large, mature oil and gas fields even though moderately deep hydrocarbon production has generally been disregarded as the primary cause. This project will test the hypothesis that long-term, large-volume oil and gas production in the Gulf Coast Basin has resulted in land-surface subsidence and activation of deep-seated faults around some fields. Posted: 2003-03-14
USGS OFR 03-13 - Cascadia Tsunami Deposit Database The Cascadia Tsunami Deposit Database contains data on the location and sedimentological properties of tsunami deposits found along the Cascadia margin. Data have been compiled from 52 studies, documenting 59 sites from northern California to Vancouver Island, British Columbia that contain known or potential tsunami deposits. Bibliographical references are provided for all sites included in the database. Cascadia tsunami deposits are usually seen as anomalous sand layers in coastal marsh or lake sediments. The studies cited in the database use numerous criteria based on sedimentary characteristics to distinguish tsunami deposits from sand layers deposited by other processes, such as river flooding and storm surges. Several studies cited in the database contain evidence for more than one tsunami at a site. Data categories include age, thickness, layering, grainsize, and other sedimentological characteristics of Cascadia tsunami deposits. The database documents the variability observed in tsunami deposits found along the Cascadia margin. Posted: 2003-01-01
West-Central Florida Coastal Transect #3: Sand Key - USGS Open File Report 99-507 This is the third of nine transect areas extending from the mainland of west-central Florida out to a depth of 26m. Data collected and presented includes sediment core data and side-scan sonar mapping of portions of the seafloor. Posted: 2002-12-17
West-Central Florida Coastal Transect #8: Siesta Key - USGS Open File Report 99-512 This is the eighth of nine transect areas extending from the mainland of west-central Florida out to a depth of 26m. Data collected and presented includes sediment core data and side-scan sonar mapping of portions of the seafloor. Posted: 2002-12-17
West-Central Florida Coastal Transect #9: Casey Key - USGS Open File Report 99-513 This is the ninth of nine transect areas extending from the mainland of west-central Florida out to a depth of 26m. Data collected and presented includes sediment core data and side-scan sonar mapping of portions of the seafloor. Posted: 2002-12-17
Subsidence and Sea-Level Rise in Southeastern Louisiana: Implications for Coastal Management and Restoration The Mississippi River delta plain is subject to the highest rate of relative sea-level rise (3 ft per century) of any region in the Nation largely due to rapid geologic subsidence. This collaborative study is responsible for developing an objective and reliable scientific database on subsidence and sea-level rise by conducting detailed studies within the Mississippi River delta plain. Posted: 2002-12-12
USGS - Lake Pontchartrain Geochemistry Lake Pontchartrain, as the largest estuary in southern Louisiana, is an important recreational, commercial, and environmental resource for New Orleans, southeastern Louisiana, and the Nation. This publication is one of the products resulting from a 5-year cooperative program started in 1995 by the U.S. Geological Survey (http://coastal.er.usgs.gov/pontchartrain/). The program is focused on the geological framework and sedimentary processes of the Lake Pontchartrain Basin. Detailed documentation of selected aspects of the cooperative program are provided here. Posted: 2002-10-16
Shallow Stratigraphic Evidence of Subsidence and Faulting Induced by Hydrocarbon Production in Coastal Southeast Texas - USGS Open File Report 01-274 Wetland losses and their progressive conversion to open water around producing oil and gas fields in the Gulf Coast region have been attributed to a variety of natural and anthropogenic processes. Three large, mature hydrocarbon fields in coastal southeast Texas were examined to evaluate competing hypotheses of wetland losses and to characterize subaerial and submerged surfaces near reactivated faults and zones of subsidence. Posted: 2002-09-19
Subsidence and Fault Activation Related to Fluid Energy Production, Gulf Coast Basin The Gulf Coast Basin is a region where subsidence and fault activation are common around large, mature oil and gas fields even though moderately deep hydrocarbon production has generally been disregarded as the primary cause. This project will test the hypothesis that long-term, large-volume oil and gas production in the Gulf Coast Basin has resulted in land-surface subsidence and activation of deep-seated faults around some fields. Posted: 2002-09-18
Chemical Pollutants and Toxic Effects on Benthic Organisms, Biscayne Bay, Florida Through the study of benthic foraminifera in Florida's Biscayne Bay, this project seeks to identify the distribution of pollutants and their effects in the bay. Findings will be used to assist in planning Everglades restoration and to aid in understanding recent change in local coral reef health. Posted: 2002-08-27
Temporal changes in grain size and organic-mineral aggregatesin surficial sediments near the Massachusetts Bay Outfall Site, Title Page This report summarizes the time-series analyses of grain size distribution and the abundance of organic-mineral aggregates in surface sediments at two monitoring stations near the Massachusetts Bay Outfall. Sediments, especially the finer fractions, can adsorb contaminants from sea water and exert a strong influence on the transport and ultimate distribution of contaminants. Therefore, it is important to know the extent to which sediment characteristics in Massachusetts Bay can change in response both to natural events, such as storms, and to the start of the new sewage outfall. Posted: 2002-08-12
U.S. Geological Survey - Historic Area Remediation Site (HARS) Web Page Three multibeam echosounder surveys were carried out to map the topography and surficial geology of the Historic Area Remediation Site (HARS) located offshore of New York City. The surveys were conducted November 23 - December 3, 1996, October 26 - November 11, 1998, and April 6 - 30, 2000. This report presents maps showing topography, shaded relief, and backscatter intensity (a measure of sea floor texture and roughness) at a scale of 1:25,000. Comparison of the topography and backscatter intensity from the three surveys show changes in topography and surficial sediment properties resulting from placement of dredged material in 1996 and 1997 prior to closure of the Mud Dump Site, as well as placement of capping material for remediation of the HARS. Posted: 2002-07-09
USGS Sediment Studies in Lake Mead Lake Mead is one of the world's largest man-made reservoirs at about 600 sq km, roughly the size of Chicago. Lake Mead started to form on the Colorado River in 1935, upon completion of the Hoover Dam. Since then, the lake has supplied water to agricultural, industrial, recreational, and municipal users in the southwestern United States. Posted: 2002-05-15
Environmental Atlas of the Lake Pontchartrain Basin - USGS Open File Report 02-206 The Environmental Atlas of the Lake Pontchartrain Basin provides citizens, planners, managers, educators, scientists and other professionals with a multidisciplinary and integrated source of information on Lake Pontchartrain and its surrounding Basin. Posted: 2002-05-14
U.S.G.S. Woods Hole Field Center, Analytical Labs This page documents the laboratories, methods, and equipment used to analyze marine sediments at the USGS's Woods Hole Field Center. Posted: 2002-04-25
Gas Hydrate at the USGS Gas hydrate is a crystalline solid formed of water and gas. It looks and acts much like ice, but it contains huge amounts of methane and it exists in very large quantities in marine sediments in a layer several hundred meters thick directly below the sea floor and in association with permafrost in the Arctic. It is important for three reasons: 1. It may become a major energy resource, 2. It has important effects on sea floor sediment stability, influencing collapse and landsliding, 3. The hydrate reservoir may have strong influence on climate, as methane is a significant greenhouse gas. This project seeks to learn to identify gas hydrate by remote sensing and to understand the processes that control methane hydrate in the natural environment, such as concentration into possibly extractable accumulations, change in strength of sediments and generation of overpressures, processes of seafloor mobilization, and processes allowing transfer of methane to the atmosphere. Posted: 2002-04-24
USGS Studies in Long Island Sound: Geology, Contaminants, and Environmental Issues Long Island Sound is a major coastal estuary near the New York-Connecticut metropolitan area. More than eight million people live in its watershed. Due to the enormous population, the Sound is used heavily and its sea floor has been impacted by human activities. There are many benthic habitats in the Sound that support large commercial and recreational fisheries. Sediments of the Sound are a sink for wastes and contaminants from various sources such as wastewater treatment plants, urban and agricultural runoff, and waste disposal. Posted: 2002-04-24
Community Coastal Sediment-Transport Model Project Page The United States Geological Survey and others is promoting the development of an open-source numerical model for sediment-transport in coastal regions. We are collaborating with other federal agencies, academic institutions, and private industry, with the goal of adopting and/or developing one or more models for use as scientific tools by the research community. Posted: 2002-04-24
Coral Reefs in Honduras: Status after Hurricane Mitch - Online Mini-Documentary Movie "Coral Reefs in Honduras: Status after Hurricane Mitch" is an eight minute mini-documentary featuring geologist Bob Halley describing the USGS response in the wake of Hurricane Mitch to assess the impact of the storm on Caribbean coral reefs off Honduras. Narrated by geologist Terry Edgar. Posted: 2002-04-05
Atchafalaya and Mississippi River Deltas Study This study will evaluate the transport and storage of particle reactive, environmentally relevant contaminates through the Mississippi River and Atchafalaya River delta complexes to the near-shore Gulf of Mexico. Posted: 2002-03-18
U.S. Geological Survey Studies in the New York Bight Since 1992, the U.S. Geological Survey`s Coastal and Marine Geology Program has been conducting studies offshore of New York designed to map and characterize the sea floor, to understand the transport and fate of sediments and associated pollutants, to map the inner shelf and sand deposits along the southern shore of Long Island, and to understand the recent geologic history. A long-term goal of these geological studies is to develop predictive models and geologic information to guide research and sustainable use of the coastal ocean. Posted: 2001-12-14
Online Mini-Documentary Movie - The Effects of Globally Transported African and Asian Dust on Coral Reef and Human Health "The Effects of Globally Transported African and Asian Dust on Coral Reef and Human Health" is an eight minute mini-documentary featuring biologist Ginger Garrison, geologist Gene Shinn, chemist Chuck Holmes, and microbiologist Dale Griffin as they explain the deterioration of Caribbean coral health over the past several decades, and how unlocking the key role of trans-Atlantic dust transport has opened the door to understanding the effects and implications of this global phenomenon. Narrated by geologist Terry Edgar. Posted: 2001-11-08
West-Central Florida Coastal Studies This project is a study of the west central Florida coast, conducted by the U.S. Geological Survey, University of South Florida, and Eckerd College. The study investigates the formation and maintanance of the barrier island system, as well as the geologic framework of the region. Posted: 2001-10-31
USGS Open-File Report 01-356 Sediment chemistry data are presented for the Massachusetts Bay Outfall Posted: 2001-10-23
A Marine GIS Library for Massachusetts Bay: This CD-ROM contains information in a Geographic Information System (GIS) format (ESRI's ArcView) for the coastal region offshore of Boston, Massachusetts. This collection of coverages (here defined as ArcView shapefiles, grids and TIFs) is a beginning effort to develop a library of information in GIS format that can be referenced and shared by those working in, and seeking to understand, the Massachusetts Bay region. The CD-ROM was assembled at a workshop attended by an ad-hoc group representing federal and state government, industry and academia. This CD-ROM principally contains data on waste disposal sites and characteristics of the sea floor. Posted: 2001-10-15
USGS EAST-COAST SEDIMENT ANALYSIS: PROCEDURES, DATABASE, AND GEOREFERENCED DISPLAYS This CD-ROM contains descriptions of the field and laboratory methods used to collect and process sediment samples at the Woods Hole Field Center for Coastal and Marine Geology Program, USGS in Woods Hole, Massachusetts; an archive of digitally-available sediment data generated at this facility between 1962 and 2000; and data layers that can be viewed with geographic mapping tools. Posted: 2001-10-12
Photographs of the seafloor in Western Massachusetts Bay This CD-ROM contains photographs and sediment sample analyses of the sea floor obtained at 142 sites in western Massachusetts Bay (Figure 1) during a research cruise (USGS cruise ISBL99024) aboard the Fishing Vessel (FV) Isabel S. (Figure 2) conducted July 18-21, 1999. These photographs and samples provide critical ground truth information for the interpretation of shaded relief and backscatter intensity maps created using data collected with a multibeam echo sounder system (Butman and others, in press, a, b, c; Valentine and others, in press, a, b, c). Collection of these photographs and samples was undertaken in support of a large project whose overall objective is to map and describe the sea floor of Massachusetts Bay. Posted: 2001-10-10
U.S. Geological Survey Open-File Report 01-041 This Open-File Report contains a compilation of the laboratory methods used to perform X-ray powder diffraction analyses and to determine the clay mineralogy of marine sediments at the USGS Coastal and Marine Geology Program Woods Hole Field Center in Woods Hole, Massachusetts. Posted: 2001-10-10
U.S. Geological Survey Open-File Report 01-154 This Open-File Report contains bottom photographs that were collected in the early 1960's as part of the U. S. Geological Survey's Continental Margin Program. This joint program conducted with the USGS and the Woods Hole Oceanographic Institution conducted a geologic reconnaissance investigation of the continental shelf and slope off the Atlantic coast of the United States. As part of the program nearly 3800 locations were occupied that extended from the Canadian border to the southern tip of Florida. Bottom photography was completed at many of these stations in conjunction with sediment sampling. This report provides a digital release of the historical photos collected collected at these stations. Posted: 2001-09-26
Surficial Geology and Distribution of Post-Impoundment Sediment in Las Vegas Bay, Lake Mead, U.S. Geological Open-File Report 01-070, Title Page Sidescan sonar imagery and seismic-reflection profiles were collected in the northwestern part of Las Vegas Bay to map the distribution and volume of sediment that has accumulated in this part of Lake Mead since impoundment. The mapping suggests that three ephemeral streams are the primary source of this sediment, and of these, Las Vegas Wash is the largest. Two deltas off the mouth of Las Vegas Wash formed at different lake elevations and account for 41% of the total volume of post-impoundment sediment within the study area. Deltas off the other two washes (Gypsum and Government) account for only 6% of the total volume. The sediment beyond the front of the deltas is primarily mud, and it only occurs in valley floors, where it forms a flat-lying blanket that is mostly less than 1.5 m thick. Although a thin layer, the fine-grained sediment accounts for approximately 53% of the total post-impoundment sediment volume of 5.7 x 106 m3 that has accumulated in the study area. This sediment appears to have been transported several kilometers from the river sources by density flows. Posted: 2001-09-07
Remote Sensing Applications to Coral Reef Environments The main goal of this project is to investigate and analyze remotely sensed image data to determine their applicability for detecting and mapping the location of live and dead reef areas, density of coral cover, and the major type of coral present, as well as algae, silt/mud, and carbonate sand cover. Posted: 2001-09-04
U.S. Geological Survey Open-File Report 01-194 sediment core descriptions, x-radiographs, quantitative analytical data including water content, biogenic silica content, magnetic susceptibility, trace-metal concentrations, stable isotope ratios, organic carbon and nitrogen contents. Posted: 2001-08-20
A Photo Gallery of Florida's Big Bend Tidal Wetlands This collection offers a thematic tour of Florida's Big Bend tidal wetlands, covering aspects of the flora, fauna, and geology of this mosaic of tidal marsh, coastal forest, and winding tidal creeks. Posted: 2001-02-23
Great Lakes Mapping Project Initiative to map lake bathymetry and classify lakebed materials to advance knowledge of Great Lakes and enable better management of Great Lakes resources. Posted: 2000-12-12
Gulf of the Farallones Waste-Disposal Issues Studies about disposal of radioactive waste and dredged material in the Gulf of the Farallones National Marine Sanctuary, offshore of San Francisco, California Posted: 2000-07-19
Sediment-Transport Workshop Report Report of the Community Sediment Transport Modeling Workshop, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts, U. S. A. on 22-23 June, 2000 Posted: 2000-06-23
Geologic Framework and Processes of the Lake Pontchartrain Basin Lake Pontchartrain and adjacent lakes form one of the largest and most important estuaries in the Gulf Coast Region. The estuary drains the Pontchartrain Basin, an area of over 12,000 square kilometers situated on the eastern side of the Mississippi River delta plain. In Louisiana, nearly one-third of the state population lives within the 14 parishes of the Pontchartrain Basin. Posted: 2000-03-15
Geologic Characterization of Lakes and Rivers of Northeast Florida This study is part of a series of cooperative investigations conducted from 1993 to 1997 of inland and offshore waters and adjacent terrain throughout much of the St. Johns River Water Management District in northeastern Florida. Posted: 2000-03-03
Seismic Stratigraphy of the Central Indian River Region - Open File Report 97-723 The geology and and hydrology of the central Indian River region along the central east coast of Florida is of critical concern to the St. Johns River Water Management District (SJRWMD). In this area the upward migration of deeper, more saline ground water in the lower Floridan aquifer to the shallower, fresher ground water of the upper Floridan aquifer and above, may impact the water quality of this resource. Posted: 2000-02-29
South Carolina Coastal Erosion Study In South Carolina, the physical processes responsible for coastal erosion are complex, difficult to measure and complicated by the influence of many tidal inlets. Understanding the relative contributions of processes causing coastal erosion is important to mitigation of beach erosion. Posted: 1999-06-03
National Coastal Assessment The coastal margin of the US is among the most densely populated, developed, property valued, tax generating, income generating, and recreational valued region of the US. The dynamic natural processes and human-induced changes within this margin are poorly understood yet result in a highly mobile coastal zone that is subject to rapid (decadal or less) change. The goal of this project is to develop a GIS based inventory of scientific data including those variables known to contribute to coastal change. Posted: 1999-05-14
Short and Long-Term Variability of Ebb-Tidal Deltas: Management Implications With the increasing demand for suitable beach fill material, coastal planners often covet ebb-tidal shoal sands due to their (typically) coarse grain size and proximity to the beach. However, these sand bodies are rarely mined because of potential adverse effects on adjacent shorelines. The quantification of sediment volumes in an ebb-tidal delta over short and long time spans can be used to identify the system's natural variability. Posted: 1999-03-18
South Carolina Quaternary Geologic Framework South Carolina's central coast and inner shelf from North Edisto River to Bull's Inlet has a complex Quaternary history of transgressive and regressive sedimentary sequences. These sequences were identified from 612 line-km of high-solution single-channel seismic profiles, side-scan sonar mosaics, 81 vibracores, ground penetrating radar, Amino acid racemization, and compilation of previous investigations. Posted: 1998-11-20
USGS TerraWeb: San Francisco Bay - Multibeam Backscatter Data: Alcatraz Island and West-Central Bay Areas Remote sensing in the Central San Francisco Bay Region, featuring multibeam backscatter and bathymetry mosaics products enhanced with satellite imagery. The image maps featured were created to help study sediment and pollutant transport in Central San Francisco Bay -- visit this page for links to the Sediment and Pollutant Trasport project and related web pages. Posted: 1998-05-20
A Giant Sediment Trap in the Florida Keys Aerial photography, high resolution seismic profiling, coring and jet probing have revealed a large sediment-filled sinkhole in the Key Largo National Marine Sanctuary off Key Largo, Florida. The 600-m-diameter feature straddles coral reef and carbonate-sand facies and contains >55 m of marine lime sand and aragonite mud. Posted: 1998-04-21
Grand Canyon Colorado River Studies Studies of sediment transport in the Grand Canyon, Arizona - using ocean research techniques to study a river system. Posted: 1997-06-09
U.S. Department of the Interior |
U.S. Geological Survey
Project Information
Photographs
Movies
Maps
Publications
Data Sets