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At least 37 records · Page 2Linked to original sources
USGS2001

The STRATAFORM Project: U.S. Geological Survey geotechnical studies

This report presents physical property logs of core samples from an offshore area near Eureka, CA. The cores were obtained as part of the STRATAFORM Program (Nittrouer and Kravitz, 1995, 1996), a study investigating how present sedimentation and sediment transport processes influence long-term stratigraphic sequences preserved in the geologic record. The core samples were collected during four separate research cruises to the northern California study area, and data shown in the logs of the cores were collected using a multi-sensor whole core logger. The physical properties collected are useful in identifying stratigraphic units, ground-truthing acoustic imagery and sub-bottom profiles, and in understanding mass movement processes. STRATA FOR mation on M argins was initiated in 1994 by the Office of Naval Research, Marine Geology and Geophysics Department as a coordinated multi-investigator study of continental-margin sediment transport processes and stratigraphy (Nittrouer and Kravitz, 1996). The program is investigating the stratigraphic signature of the shelf and slope parts of the continental margins, and is designed to provide a better understanding of the sedimentary record and a better prediction of strata. Specifically, the goals of the STRATAFORM Program are to (Nittrouer and Kravitz, 1995): - determine the geological relevance of short-term physical processes that erode, transport, and deposit particles and those processes that subsequently rework the seabed over time scales <10 2 years. - improve capabilities for identifying the processes that form the strata observed within the upper ~100 m of the seabed commonly representing 104-106 years of sedimentation. - synthesize this knowledge and bridge the gap between time scales of sedimentary processes and those of sequence stratigraphy. The STRATAFORM Program is divided into studies of the continental shelf and the continental slope; the geotechnical group within the U.S. Geological Survey provides support to both parts of the project.

California↗
USGS2012

The hydrothermal system at Newberry Volcano, Oregon

Results of recent geological and geophysical studies at Newberry Volcano have been incorporated into conceptual and numerical models of a magma-based hydrothermal system. Numerical simulations begin with emplacement of a small magma body, the presumed source of silicic eruptions at Newberry that began about 10,000 B.P., into a thermal regime representing 100,000 years of cooling of a large underlying intrusion. Simulated flow patterns and thermal histories for three sets of hypothetical permeability values are compatible with data from four geothermal drill holes on the volcano. Meteoric recharge cools the caldera-fill deposits, but thermal water moving up a central conduit representing a permeable volcanic vent produces temperatures close to those observed in drill holes within the caldera. Meteoric recharge from the caldera moves down the flanks and creates a near-isothermal zone that extends several hundred meters below the water table, producing temperature profiles similar to those observed in drill holes on the flanks. The temperatures observed in drill holes on the flanks are not influenced by the postulated Holocene magma body. The elevated temperature gradients measured in the lower portions of these holes may be related to the cumulative effect of older intrusions. The models also indicate that meteoric recharge to the deep hydrothermal system probably originates within or near the caldera. Relatively low fluid velocities at depth suggest that at least a significant fraction of the thermal fluid may be very old.

Journal of Geophysical Research Solid Earth↗
USGS2006

High-resolution geologic mapping of the inner continental shelf: Nahant to Gloucester, Massachusetts

This report presents high-resolution maps of the seafloor offshore of Massachusetts, from Nahant to Gloucester. Approximately 134 km² of the inner shelf were mapped with a focus on the nearshore region in water depths less than 40 m (fig. 1.1). The maps were prepared as part of a cooperative mapping program between the U.S. Geological Survey (USGS) and the Massachusetts Office of Coastal Zone Management (CZM). They are based on marine geophysical data, sediment sampling, and bottom photography obtained on two research cruises carried out in 2003 and 2004. The primary objective of this program is to develop a suite of seafloor maps that provide geologic information for management of coastal and marine resources. Accurate maps of seafloor geology are important first steps toward protecting fish habitat, delineating marine reserves, and assessing environmental changes due to natural or human impacts. The maps also provide a geologic framework for scientific research, industry and the public. The organization of this report is outlined in the navigation bar along the left-hand margin of the page. This is section 1, the introduction. Section 2 briefly describes the mapping products contained in this report and has links to large-format map sheets, that can be viewed on line or downloaded. Section 3 is a description of the data collection, processing, and analysis procedures used to create the map products. Section 4 examines the geologic framework and late Quaternary evolution of the region, and presents two different strategies for mapping the complex seafloor. This report also contains four appendices that include GIS layers of all data collected in this study, and copies of the sample and photographic data used to validate the interpretations.

Massachusetts↗
USGS2012

USGS advances in integrated, high-resolution sea-floor mapping: inner continental shelf to estuaries

The U.S. Geological Survey (USGS) has been involved in geological mapping of the sea floor for the past thirty years. Early geophysical and acoustic mapping efforts using GLORIA (Geologic LOng Range Inclined ASDIC) a long-range sidescan-sonar system, provided broad-scale imagery of deep waters within the U.S. Exclusive Economic Zone (EEZ). In the early 1990's, research emphasis shifted from deep- to shallow-water environments to address pertinent coastal research and resource management issues. Use of shallow-water, high-resolution geophysical systems has enhanced our understanding of the processes shaping shallow marine environments. However, research within these shallow-water environments continues to present technological challenges.

Conference Paper↗
USGS2005

Chapter J: Issues and challenges in the application of geostatistics and spatial-data analysis to the characterization of sand-and-gravel resources

Sand-and-gravel (aggregate) resources are a critical component of the Nation's infrastructure, yet aggregate-mining technologies lag far behind those of metalliferous mining and other sectors. Deposit-evaluation and site-characterization methodologies are antiquated, and few serious studies of the potential applications of spatial-data analysis and geostatistics have been published. However, because of commodity usage and the necessary proximity of a mine to end use, aggregate-resource exploration and evaluation differ fundamentally from comparable activities for metalliferous ores. Acceptable practices, therefore, can reflect this cruder scale. The increasing use of computer technologies is colliding with the need for sand-and-gravel mines to modernize and improve their overall efficiency of exploration, mine planning, scheduling, automation, and other operations. The emergence of megaquarries in the 21st century will also be a contributing factor. Preliminary research into the practical applications of exploratory-data analysis (EDA) have been promising. For example, EDA was used to develop a linear-regression equation to forecast freeze-thaw durability from absorption values for Lower Paleozoic carbonate rocks mined for crushed aggregate from quarries in Oklahoma. Applications of EDA within a spatial context, a method of spatial-data analysis, have also been promising, as with the investigation of undeveloped sand-and-gravel resources in the sedimentary deposits of Pleistocene Lake Bonneville, Utah. Formal geostatistical investigations of sand-and-gravel deposits are quite rare, and the primary focus of those studies that have been completed is on the spatial characterization of deposit thickness and its subsequent effect on ore reserves. A thorough investigation of a gravel deposit in an active aggregate-mining area in central Essex, U.K., emphasized the problems inherent in the geostatistical characterization of particle-size-analysis data. Beyond such factors as common drilling methods jeopardizing the accuracy of the size-distribution curve, the application of formal geostatistical principles has other limitations. Many of the variables used in evaluating gravel deposits, including such sedimentologic parameters as sorting and such United Soil Classification System parameters as gradation coefficient, are nonadditive. Also, uniform sampling methods, such as drilling, are relatively uncommon, and sampling is generally accomplished by a combination of boreholes, water-well logs, test pits, trenches, stratigraphic columns from exposures, and, possibly, some geophysical cross sections. When evaluated in consideration of the fact that uniform mining blocks are also uncommon in practice, subsequent complexities in establishment of the volume/variance relation are inevitable. Several approaches exist to confront the limitations of geostatistical methods in evaluating sand-and-gravel deposits. Initially, we must acknowledge the practical requirements of the aggregate industry, as well as the limitations of the data collected by that industry, as a function of what the industry requires at the practical level, and consider that broader acceptance of formal geostatistics may require modifications of typical exploration and sampling protocols. Future investigations should utilize data from the full spectrum of sand-and-gravel deposits (flood plain, glacial, catastrophic flood, and marine), integrate such other disci plines as sedimentology and geophysics into the research, develop commodity-specific approaches to nonadditive variables, and include the results of comparative drilling.

Bulletin↗
USGS2012

Geochemistry of thermal waters in Long Valley, Mono County, California

Thermal springs and wells in Long Valley, California, issue sodium bicarbonate‐chloride waters containing 1000–1420 mg/l of dissolved solids. Thermal waters of sodium bicarbonate‐chloride composition are usually associated with hot‐water reservoirs. Chloride concentrations and stable isotope data indicate that the thermal waters have had varied histories. All of the thermal springs issue a mixture of fluid from the thermal reservoir and less saline, cooler water from one or more shallow aquifers. The composition of springs in Hot Creek Gorge may have been further altered by minor subsurface boiling. Thermal springs between Hot Creek and Lake Crowley issue mixtures of fresh and thermal waters which have lost heat by conductive cooling and changed composition by reaction with rock in the shallow aquifer. The silica content of water from Magma Richie 5 and mixing calculations based on the concentrations of silica in thermal waters collected from springs in Hot Creek Gorge and along Little Hot Creek indicate a temperature of at least 200°C in the thermal reservoir. The sodium‐potassium‐calcium geothermometer yields a reservoir temperature estimate near 200°C for most of the thermal springs. If geothermal energy is developed in Long Valley, the high concentrations of arsenic (up to 2.2 mg/l), boron (up to 15 mg/l), and total dissolved solids in the thermal fluids will make it necessary to isolate the effluent of production wells from the freshwater system.

California↗
USGS2015

Near-surface stratigraphy and morphology, Mississippi Inner Shelf, northern Gulf of Mexico

Over the past decade, the Mississippi Barrier Islands have been the focus of a comprehensive geologic investigation by the U.S. Geological Survey (USGS), in collaboration with the U.S. Army Corps of Engineers (USACE) and the National Park Service (NPS). The islands (Dauphin, Petite Bois, Horn, East Ship, West Ship, and Cat) are part of the Gulf Islands National Seashore (GUIS), and provide a diverse ecological habitat, protect the mainland from storm waves, and help maintain estuarine conditions within Mississippi Sound. Over the past century, the islands have been in a state of decline with respect to elevation and land-area loss. In 2005, the islands were severely impacted by Hurricane Katrina, which inundated them with a storm surge of 8 meters, causing severe shoreface erosion and widening breaches in Dauphin, West Ship, and Cat Islands. To evaluate the impact and fate of the islands, understanding their evolution and resiliency became a priority for the USGS under the Northern Gulf of Mexico Ecosystem Change and Hazard Susceptibility Project. The project formed the basis for collaboration with the USACE Mississippi Coastal Improvement Project, which is intended to restore portions of coastal Mississippi and GUIS affected by storm impact. Since then, many studies have contributed to our understanding of the islands&rsquo; morphology and nearshore stratigraphy. This report expands upon the nearshore component to provide a stratigraphic and morphologic assessment offshore of Petit Bois Island. In June 2013, as part of the MsCIP project, the USGS conducted a geophysical survey consisting of about 650 line-kilometers (km), encompassing an area of approximately 212 square kilometers (km 2 ). The survey area extended from 1 to 13 km offshore of Petite Bois Island. The geophysical investigation included interferometric swath bathymetry, sidescan sonar, and chirp subbottom profiling. The intent of the survey was to provide geologic information that would assist the USACE in developing a sediment sampling strategy for identifying deposits suitable for shoreline restoration operations. The data from the geophysical survey would also further our understanding of the geologic framework along the inner shelf. Numerous seafloor and subbottom features were identified. At the surface, shoals and shelf sand sheets of various sizes and orientations are the predominant morphology. In the subsurface, Holocene- and Pleistocene-age features include marine transgressive deposits infilling older fluvia distributary systems. These interpretations from the geophysical research were integrated with sediment cores collected by the USGS and USACE to provide textural and volumetric information.

Mississippi-Alabama shelf↗
USGS1991

Publications of the Branch of Atlantic Marine Geology for Calendar Year 1990

This U.S. Geological Survey Open-File Report [extract] contains a listing of publications authored or co-authored by members of the Branch of Atlantic Marine Geology and published in calendar year 1990. The Branch conducts a broad geologic and geophysical research and mapping program, primarily along the U.S. Atlantic Margin, in the Great Lakes, the Gulf of Mexico, the Caribbean and polar regions. A long range objective of this program is to develop a comprehensive understanding of the geology of the continental margin and a predictive capability to guide and assess the consequences of its use. Headquarters of the Branch of Atlantic Marine Geology are located in Woods Hole, MA., and personnel are located in Woods Hole, MA., St Petersburg, FL., Reston, VA., Denver, CO., and San Juan, Puerto Rico. A brochure describing the Branch of Atlantic Marine Geology may be obtained by writing to Chief, Branch of Atlantic Marine Geology, Quissett Campus, Woods Hole, MA 02543. Results of Branch investigations are distributed in a variety of ways, including maps, journal articles, abstracts and U.S.G.S. publications. Copies of U.S.G.S. Open File Reports may be obtained from the author. Book publications can be obtained from U.S. Geological Survey, Books and Reports Sales, Federal Center, Box 25425, Denver, CO 80225. Copies of U.S.G.S. Maps may be obtained from the U.S. Geological Survey, Map Sales, Federal Center, Box 25286, Denver, CO 80225.

Open-File Report↗
USGS1994

Publications of the Branch of Atlantic Marine Geology for Calendar Year 1993

This U.S. Geological Survey Open-File Report [extract] contains a listing of publications authored or co-authored by members of the Branch of Atlantic Marine Geology and published in calendar year 1993. The Branch conducts a broad geologic and geophysical research and mapping program, primarily along the U.S. Atlantic Margin, in the Great Lakes, the Gulf of Mexico, the Caribbean and polar regions. A long range objective of this program is to develop a comprehensive understanding of the geology of the continental margin and a predictive capability to guide and assess the consequences of its use. Headquarters of the Branch of Atlantic Marine Geology are located in Woods Hole, MA., and personnel are located in Woods Hole, MA., St Petersburg, FL., Reston, VA., Denver, CO., and San Juan, Puerto Rico. A brochure describing the Branch of Atlantic Marine Geology may be obtained by writing to Chief, Branch of Atlantic Marine Geology, Quissett Campus, Woods Hole, MA 02543. Results of Branch investigations are distributed in a variety of ways, including maps, journal articles, abstracts and U.S.G.S. publications. Copies of U.S.G.S. Open File Reports may be obtained from the author. Book publications can be obtained from U.S. Geological Survey, Books and Reports Sales, Federal Center, Box 25425, Denver, CO 80225. Copies of U.S.G.S. Maps may be obtained from the U.S. Geological Survey, Map Sales, Federal Center, Box 25286, Denver, CO 80225.

Open-File Report↗
USGS2018

Chirp subbottom profile data collected in 2015 from the northern Chandeleur Islands, Louisiana

As part of the Barrier Island Evolution Research project, scientists from the U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted a nearshore geophysical survey around the northern Chandeleur Islands, Louisiana, in September 2015. The objective of the project is to improve the understanding of barrier island geomorphic evolution, particularly storm-related depositional and erosional processes that shape the islands over annual to interannual time scales (1–5 years). Collecting geophysical data can help researchers identify relations between the geologic history of the islands and their present day morphology and sediment distribution. High-resolution geophysical data collected along this rapidly changing barrier island system can provide a unique time-series dataset to further the analyses and geomorphological interpretations of this and other coastal systems, improving our understanding of coastal response and evolution over medium-term time scales (months to years). Subbottom profile data were collected in September 2015 offshore of the northern Chandeleur Islands, during USGS Field Activity Number 2015-331-FA. Data products, including raw digital chirp subbottom data, processed subbottom profile images, survey trackline map, navigation files, geographic information system data files and formal Federal Geographic Data Committee metadata, and Field Activity Collection System and operation logs are available for download.

Louisiana↗
USGS2014

Coastal bathymetry data collected in 2011 from the Chandeleur Islands, Louisiana

As part of the Barrier Island Evolution Research project, scientists from the U.S. Geological Survey St. Petersburg Coastal and Marine Science Center conducted nearshore geophysical surveys off the northern Chandeleur Islands, Louisiana, in June of 2011. The overall objectives of the study are to better understand barrier-island geomorphic evolution, particularly storm-related depositional and erosional processes that shape the islands over annual to interannual timescales (1-5 years). Collection of geophysical data will allow us to identify relationships between the geologic history of the island and its present day morphology and sediment distribution. This mapping effort was the first in a series of three planned surveys in this area. High resolution geophysical data collected in each of three consecutive years along this rapidly changing barrier-island system will provide a unique time-series dataset that will significantly further the analyses and geomorphological interpretations of this and other coastal systems, improving our understanding of coastal response and evolution over short time scales (1-5 years). This data series includes the bathymetric data that were collected during two cruises ( USGS Field Activity Numbers 11BIM01 and 11BIM02 ) aboard the Research Vessel (R/V) SurveyCat and the R/V TwinVee along the northern portion of the Chandeleur Islands, Breton National Wildlife Refuge , Louisiana. Data were acquired with the following equipment: a Systems Engineering and Assessment, Ltd., SWATH plus interferometric sonar (234 kilohertz), an EdgeTech 424 (4-24 kHz) chirp sub-bottom profiling system, and a Marimatech E-SEA Sound 206 (200 kHz) echosounder. This report serves as an archive of processed interferometric swath and single-beam bathymetry data. Geographic Iinformation System data products include a 50-meter cell-size interpolated bathymetry grid surface, trackline maps, and point data files. Additional files include error analysis maps, Field Activity Collection System logs, and formal Federal Geographic Data Committee metadata.

Louisiana↗
USGS2007

Mapping and vessel-based capabilities

U.S. Geological Survey (USGS) scientists from the Florida Integrated Science Center (FISC) conduct scientific investigations of submerged coastal and marine resources using new and existing technologies. Each contributing technique, method, or product adds to our understanding of coastal and marine resources and provides information for resource-management decisionmaking. In support of this mission, the USGS St. Petersburg office maintains a fleet of research vessels used for inland, coastal, and open-water marine surveys and investigations. Each vessel has advantages and limitations related to water depth, carrying capacity, speed, operation in open water, and other functions. These research platforms are staffed by experienced technical and scientific professionals with expertise in marine navigation, geology, geophysics, engineering, biology, and oceanography.

Fact Sheet↗
USGS2024

Seabed maps showing topography, ruggedness, backscatter intensity, sediment mobility, and the distribution of geologic substrates in quadrangle 5 of the Stellwagen Bank National Marine Sanctuary region offshore of Boston, Massachusetts

The U.S. Geological Survey, in cooperation with the National Marine Sanctuary Program of the National Oceanic and Atmospheric Administration, has conducted seabed mapping and related research in the Stellwagen Bank National Marine Sanctuary (SBNMS) region since 1993. The area being mapped using geophysical and geological data includes the SBNMS and the surrounding region, which totals approximately 3,700 square kilometers (km 2 ) and is subdivided into 18 quadrangles. The seabed is a glaciated terrain that is topographically and texturally diverse. Quadrangle 5, the subject of this scientific investigations map, has an area of 211 km 2 and has water depths that range from 23 meters (m) on the Stellwagen Bank crest to 105 m in the Stellwagen Basin. Seven map types, each at a scale of 1:25,000, depict seabed topography, ruggedness, backscatter intensity, distribution of geologic substrates, sediment mobility, distribution of fine- and coarse-grained sand, and substrate mud content. These maps show the distribution of geologic substrates on the crest and western flank of the south-central part of Stellwagen Bank and in Stellwagen Basin to the west. Interpretations of multibeam sonar bathymetric and seabed backscatter imagery, photographs, video imagery, and grain-size analyses were used to create the geology-based maps. Data from 729 stations were analyzed, including 620 sediment samples. The geologic substrate maps of quadrangle 5 show the distribution of 20 substrates that represent a wide range of textures, such as mobile and rippled sand, immobile sand, sand that partially veneers gravel, boulder ridges, and mud. Mapped substrates are characterized by sediment grain-size composition, surface morphology, substrate layering, the mobility or immobility of substrate surfaces, and water depth range. This scientific investigations map portrays the major geological elements (substrates, topographic features, and processes) of environments in quadrangle 5. It is intended to provide a foundation for research into present and past sediment transport processes in a complex terrain, provide insights into the ecological requirements of invertebrate and vertebrate species that utilize the various substrates, and to support seabed management in the region.

Massachusetts↗
USGS2024

Seabed maps showing topography, ruggedness, backscatter intensity, sediment mobility, and the distribution of geologic substrates in quadrangle 2 of the Stellwagen Bank National Marine Sanctuary region offshore of Boston, Massachusetts

The U.S. Geological Survey, in cooperation with the National Marine Sanctuary Program of the National Oceanic and Atmospheric Administration, has conducted seabed mapping and related research in the Stellwagen Bank National Marine Sanctuary (SBNMS) region since 1993. The area being mapped using geophysical and geological data includes the SBNMS and the surrounding region, which totals approximately 3,700 square kilometers (km 2 ) and is subdivided into 18 quadrangles. The seabed is a glaciated terrain that is topographically and texturally diverse. Quadrangle 2, the subject of this scientific investigations map, has a mapped area of 209 km 2 and has water depths that range from about 19 meters (m) on the Stellwagen Bank crest to about 68 m in the Stellwagen Basin. Seven map types, each at a scale of 1:25,000, depict seabed topography, ruggedness, backscatter intensity, distribution of geologic substrates, sediment mobility, distribution of fine- and coarse-grained sand, and substrate mud content. These maps show the distribution of geologic substrates across the southwestern part of Stellwagen Bank, in Stellwagen Basin to the west and southwest of the bank, and in Little Stellwagen Basin and the western part of Race Point Channel to the south of the bank. Interpretations of multibeam sonar bathymetric and seabed backscatter imagery, photographs, video imagery, and grain-size analyses were used to create the geology-based maps. Data from 733 stations were analyzed, including 656 sediment samples. The geologic substrate maps of quadrangle 2 show the distribution of 19 geologic substrates that represent a wide range of textures, such as rippled and immobile sand, immobile muddy sand and sandy mud, sand that partially veneers gravel, and a boulder ridge. Mapped substrates are characterized by sediment grain-size composition, surface morphology, substrate layering, the mobility or immobility of substrate surfaces, and water depth range. This scientific investigations map portrays the major geological elements (substrates, topographic features, and processes) of environments in quadrangle 2. It is intended to provide a foundation for research into present and past sediment transport processes in a complex terrain, provide insights into the ecological requirements of invertebrate and vertebrate species that utilize the various substrates, and support seabed management in the region.

Massachusetts↗
USGS2026

Seabed maps showing topography, ruggedness, backscatter intensity, sediment mobility, and the distribution of geologic substrates in quadrangle 3 of the Stellwagen Bank National Marine Sanctuary region offshore of Boston, Massachusetts

The U.S. Geological Survey, in cooperation with the National Marine Sanctuary Program of the National Oceanic and Atmospheric Administration, has conducted seabed mapping and related research in the Stellwagen Bank National Marine Sanctuary (SBNMS) region since 1993. The area being mapped using geophysical and geological data includes the SBNMS and the surrounding region, which totals approximately 3,700 square kilometers (km 2 ) and is subdivided into 18 quadrangles. The seabed is a glaciated terrain that is topographically and texturally diverse. Quadrangle 3, the subject of this scientific investigations map, has a mapped area of 185 km 2 and has water depths that range from about 30 meters (m) on the Stellwagen Bank crest to about 135 m in a basin east of South Ninety Bank, which lies off the eastern margin of Stellwagen Bank. Seven map types, each at a scale of 1:25,000, depict seabed topography, ruggedness, backscatter intensity, distribution of geologic substrates, sediment mobility, distribution of fine- and coarse-grained sand, and substrate mud content. These maps show the distribution of geologic substrates on the southeastern part of Stellwagen Bank, on adjacent banks and basins in deeper water to the east, in the eastern part of Race Point Channel to the south of the bank, and on the northern slope of Cape Cod. Interpretations of multibeam sonar bathymetric and seabed backscatter imagery, photographs, video imagery, and grain-size analyses were used to create the geology-based maps. Data from 309 stations were analyzed, including 279 sediment samples. The geologic substrate maps of quadrangle 3 show the distribution of 21 geologic substrates that represent a wide range of textures, such as rippled sand, immobile sand, immobile muddy sand, sand that partially veneers gravel, and boulder ridges. Mapped substrates are characterized by sediment grain-size composition, surface morphology, substrate layering, the mobility or immobility of substrate surfaces, and water depth range. This scientific investigations map portrays the major geological elements (substrates, topographic features, and processes) of environments in quadrangle 3. It is intended to provide a foundation for research into present and past sediment transport processes in a complex terrain, provide insights into the ecological requirements of invertebrate and vertebrate species that use the various substrates, and support seabed management in the region.

Quadrangle 3 of the Stellwagen Bank National Marin↗
USGS2014

Coastal bathymetry and backscatter data collected in 2012 from the Chandeleur Islands, Louisiana

As part of the Barrier Island Evolution Research Project, scientists from the U.S. Geological Survey St. Petersburg Coastal and Marine Science Center conducted nearshore geophysical surveys off the northern Chandeleur Islands, Louisiana, in July and August of 2012. The objective of the study is to better understand barrier island geomorphic evolution, particularly storm-related depositional and erosional processes that shape the islands over annual to interannual timescales (1-5 years). Collecting geophysical data will allow us to identify relationships between the geologic history of the island and its present day morphology and sediment distribution. This mapping effort was the second in a series of three planned surveys in this area. High resolution geophysical data collected in each of 3 consecutive years along this rapidly changing barrier island system will provide a unique time-series dataset that will significantly further the analyses and geomorphological interpretations of this and other coastal systems, improving our understanding of coastal response and evolution over short time scales (1-5 years). This Data Series report includes the geophysical data that were collected during two cruises ( USGS Field Activity Numbers 12BIM03 and 12BIM04 ) aboard the RV Survey Cat and the RV Twin Vee along the northern portion of the Chandeleur Islands, Breton National Wildlife Refuge, Louisiana. Data were acquired with the following equipment: a Systems Engineering and Assessment, Ltd., SWATHplus interferometric sonar (468 kilohertz (kHz)), an EdgeTech 424 (4-24 kHz) chirp sub-bottom profiling system, and a Knudsen 320BP (210 kHz) echosounder. This report serves as an archive of processed interferometric swath and single-beam bathymetry data. Geographic information system data products include an interpolated digital elevation model, an acoustic backscatter mosaic, trackline maps, and point data files. Additional files include error analysis maps, Field Activity Collection System logs, and formal Federal Geographic Data Committee metadata. NOTE: These data are scientific in nature and are not to be used for navigation.

Louisiana↗
USGS2017

Coastal bathymetry data collected in 2013 from the Chandeleur Islands, Louisiana

As part of the Barrier Island Evolution Research Project, scientists from the U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center conducted nearshore geophysical surveys around the northern Chandeleur Islands, Louisiana, in July and August of 2013. The objective of the study is to better understand barrier-island geomorphic evolution, particularly storm-related depositional and erosional processes that shape the islands over annual to interannual timescales (1‒5 years). Collecting geophysical data will allow us to identify relationships between the geologic history of the island and its present day morphology and sediment distribution. This mapping effort was the third in a series of three planned surveys in this area. High resolution geophysical data collected in each of three consecutive years along this rapidly changing barrier island system will provide a unique time-series dataset that will significantly further the analyses and geomorphological interpretations of this and other coastal systems, improving our understanding of coastal response and evolution over short time scales (1‒5 years). This data series includes the geophysical data that were collected during two cruises (USGS Field Activity Numbers (FAN) 13BIM02, 13BIM03, and 13BIM04, in July 2013; and FANs 13BIM07 and 13BIM08 in August 2013) aboard the R/V Sallenger , the R/V Jabba Jaw , and the R/V Shark along the northern portion of the Chandeleur Islands, Breton National Wildlife Refuge, Louisiana. Primary data were acquired with the following equipment: (1) a Systems Engineering and Assessment, Ltd., SWATHplus interferometric sonar (468 kilohertz [kHz]), (2) an EdgeTech 424 (4‒24 kHz) chirp sub-bottom profiling system, and (3) two Odom Hydrographic Systems, Incorporated, Echotrach CV100 single beam echosounders. This data series report serves as an archive of processed interferometric swath and single-beam bathymetry data. Geographic information system data products include an interpolated digital elevation model, trackline maps, and point data files. Additional files include error analysis maps, Field Activity Collection System logs, and formal Federal Geographic Data Committee metadata.

Louisiana↗
USGS2015

Marine geophysical data collected in a shallow back-barrier estuary, Barnegat Bay, New Jersey

In 2011, the U.S. Geological Survey, in cooperation with the New Jersey Department of Environmental Protection, began a multidisciplinary research project to better understand the water quality in Barnegat Bay, New Jersey. This back-barrier estuary is experiencing degraded water quality, algal blooms, loss of seagrass, and increases in oxygen stress, macroalgae, stinging nettles, and brown tide. The spatial scale of the estuary and the scope of challenges within it necessitate a multidisciplinary approach that includes establishing the regional geology and the estuary’s physical characteristics and modeling how the estuary’s morphology interacts to affect its water quality. This report presents the data collected during this project for use in understanding the morphology and the distribution of sea-floor and sub-sea-floor sediments within Barnegat Bay, describes the methods used to collect and process those data, and includes links to the final processed datasets. These data can be used by scientists to understand the links between geomorphology, geologic framework, sediment transport, and estuarine water quality and circulation.

New Jersey↗