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Temporal and spatial sources of silica for chert remain poorly constrained. Modern sources to the worlds oceans include silica in rivers > aeolian (dust) deposition > sea floor vents and submarine weathering. However, changes in aridity and dust flux during the Phanerozoic may explain variations in the ocean silica cycle and times and places of chert formation. The chemistry of fine quartz dust (FQD) provides a chemical mechanism for the transformation of FQD to polymorphs of silica in chert; FQD is readily dissolved, then reprecipitated as Opal-A by either biotic or abiotic processes. An unequivocal relation between increases in dust flux and biogenic opal-A in the western Pacific Ocean during the past 200 kyr...
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This map illustrates extents and types of unconsolidated deposits and bedrock in the Big Delta A-4 Quadrangle, Alaska. This map is based on field observations begun by P�w� in 1949 and by Reger in 1976. Unit characteristics and extents were determined during field visits and by interpreting 1:40,000-scale black-and-white aerial photographs taken in August 1949 and 1:63,360-scale, false-color infrared aerial photographs taken in July 1978, August 1980, and August 1981.
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This dataset summarizes various sedimentary data from ten U.S. Geological Survey (USGS) surface water sites across the contiguous United States. These sites include: 01648010 Rock Creek at Joyce Road, Washington, DC 05586300 Illinois River at Florence, Illinois 06731000 Cherry Creek below Cherry Creek Lake, Colorado 06807000 Missouri River at Nebraska City, Nebraska 06935965 Missouri River at St. Charles, Missouri 08374550 Rio Grande near Castolon, Texas 08375300 Rio Grande at Rio Grande Village, Big Bend National Park, Texas 09404200 Colorado River above Diamond Creek near Peach Springs, Arizona 11447650 Sacramento River at Freeport, California 12046260 Elwha River at diversion near Port Angeles, Washington The...
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This database portrays the surface and shallow subsurface geology of the greater Charleston, S.C. region east of 80°30′ west and south of 33°15′ north. The region covers the entirety of Charleston County and portions of Berkeley, Colleton, Dorchester, and Georgetown Counties. Units locally exposed at the surface range in age from middle Eocene to Holocene, but most of the area is covered by Quaternary interglacial deposits. These are, from oldest to youngest, the Okefenokee, Waccamaw(?), Penholoway, Ladson, Ten Mile Hill, and Wando Formations and the Silver Bluff beds. Two cross sections (not included in the database), one running southeast from Harleyville to the coastline on James Island and the other running...
Tags: Adam Run fault, Ashepoo River, Ashley Formation, Ashley River, Ashley River fault, All tags...
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Two marine geological surveys were conducted in Long Island Sound, Connecticut and New York, in fall 2017 and spring 2018 by the U.S. Geological Survey, University of Connecticut, and University of New Haven through the Long Island Sound Mapping and Research Collaborative. Sea-floor images and videos were collected at 210 sampling sites within the survey area, and surficial sediment samples were collected at 179 of the sites. The sediment data and the observations from the images and videos are used to identify sediment texture and sea-floor habitats.
Categories: Data; Types: Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, Shapefile; Tags: Atlantic Ocean, Beckman Coulter Multisizer 3, CMHRP, CSV, Coastal and Marine Hazards and Resources Program, All tags...
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Alaska Division of Geological & Geophysical Surveys (DGGS) has conducted 1:63,360-scale geologic mapping of the Sagavanirktok B-1 Quadrangle (640 square km�equivalent to four 7.5 minute quadrangles). This mapping project reinterprets micropaleontologic correlations for 17 Sagavanirktok Quadrangle wells, and reprocesses data from the one publicly-available seismic line. Surface geologic mapping, subsurface-to-surface stratigraphic age control, and seismic framework are required to reliably decipher the complex geology of this key area of the Brooks Range. Outcrops within the Sagavanirktok B-1 Quadrangle are the closest surface expressions of Prudhoe Bay source and reservoir rocks. This study yields critical petroleum-related...
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Geophysical and geological survey data were collected off Town Neck Beach in Sandwich, Massachusetts, in May and July 2016. Approximately 130 linear kilometers of subbottom (seismic-reflection) and 234-kilohertz interferometric sonar (bathymetric and backscatter) data were collected along with sediment samples, sea floor photographs, and (or) video at 26 sites within the geophysical survey area. Sediment grab samples were collected at 19 of the 26 sampling sites and video and (or) photographic imagery of the sea floor were taken at all 26 sites. These survey data are used to characterize the sea floor by identifying sediment-texture, seabed morphology, and underlying geologic structure and stratigraphy. Data collected...
The database for the Buckner 7.5-minute quadrangle straddles three terrane boundaries in the Piedmont Physiographic Province in central Virginia: the Chopawamsic terrane, the Elk Hill Complex, and the Goochland terrane. In much of the map area, the Elk Hill Complex separates the Chopawamsic and Goochland terranes. Rocks of the Chopawamsic terrane include Ordovician metavolcanic and metasedimentary rocks of the Chopawamsic Formation, Ordovician to Silurian granodiorite sheet intrusions, and Paleozoic mafic intrusions. Silurian to Devonian rocks of the Quantico Formation, mostly garnet-mica schist, crop out in the northwesternmost part of the map area, and are in unconformable contact with rocks of the Chopawamsic...
Categories: Data; Tags: Alluvium, Amphibolite, Buckner, Chopawamsic Formation, Devonian, All tags...
To determine habitat attributes and processes suitable for the growth of Coccidioides, soils were collected from sites in Arizona, California, and Utah where Coccidioides is known to have been present. Humans or animals or both have been infected by Coccidioides at all of the sites. Soil variables considered in the upper 20 cm of the soil profile included pH, electrical conductivity, salinity, selected anions, texture, mineralogy, vegetation types and density, and the overall geomorphologic and ecological settings. Thermometers were buried to determine the temperature range in the upper part of the soil where Coccidioides is often found. With the exception of temperature regimes and soil textures, it is striking...
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The natural resiliency of the New Jersey barrier island system, and the efficacy of management efforts to reduce vulnerability, depends on the ability of the system to recover and maintain equilibrium in response to storms and persistent coastal change. This resiliency is largely dependent on the availability of sand in the beach system. In an effort to better understand the system's sand budget and processes in which this system evolves, high-resolution geophysical mapping of the sea floor in Little Egg Inlet and along the southern end of Long Beach Island near Beach Haven, New Jersey was conducted from May 31 to June 10, 2018, followed by a sea floor sampling survey conducted from October 22 to 23, 2018, as part...
Categories: Data; Types: Downloadable, Map Service, OGC WFS Layer, OGC WMS Layer, Shapefile; Tags: Beach Haven, CMHRP, CSV, Coastal and Marine Hazards and Resources Program, DOI, All tags...
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The database for the Preliminary Geologic Map of the Cherry Hill Quadrangle, Dinwiddie, Sussex, and Greensville Counties, Virginia geographically straddles the Coastal Plain and Piedmont Provinces along the Tidewater Fall Line. Rocks of the eastern Piedmont Roanoke Rapids terrane crop out in the western part of the quadrangle and consist of greenschist- to amphibolite-facies Neoproterozoic felsic to intermediate metavolcanic rocks, some of which contain flattened quartz phenocrysts and are locally isoclinally folded; greenstone that is locally primary layered; and intrusive metadiorite and metagabbro, much of which has been altered to amphibolite. Most of these rocks are strongly foliated and jointed. Greenschist-facies...
Tags: Alluvial terrace, Alluvium, Amphibolite, Aplite, Atlantic coastal plain, All tags...
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This 1:50,000 scale geologic map describes the distribution of unconsolidated deposits, identifies local geologic hazards, and provides information about the depositional environment and basic engineering properties of common surficial-geologic materials in and around Shaktoolik, Alaska. Map units are the result of combined field observations and aerial imagery interpretation. A suite of local ground observations were collected over a two-week period in July 2011 by a helicopter-supported team of DGGS geologists and collaborators. Field investigations included soil test pits, sample collection, soil and rock description, oblique aerial photography, and documentation of landscape morphology.
The U.S. Geological Survey (USGS) Integrated Water Availability Assessments (IWAAs) Program is designed to deliver nationally consistent assessments of water supplies for human and ecological needs, and to identify factors that influence water availability. In support of these studies, a National-Extent Hydrogeologic Framework (NEHF) is under development. The NEHF is a three-dimensional digital representation of the subsurface of the United States. Three depth zones are of particular interest: a shallow zone within which groundwater interacts with streams (meters to tens of meters); an intermediate zone comprised of potable water (tens to hundreds of meters); and deep, saline groundwater (hundreds of meters to kilometers)....
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The geologic map database of the Great Smoky Mountains National Park region of Tennessee and North Carolina is a result from studies from 1993 to 2003 as part of a cooperative investigation by the U.S. Geological Survey with the National Park Service (NPS). This work resulted in a 1:100,000-scale geologic map derived from mapping that was conducted at scales of 1:24,000 and 1:62,500. The geologic data are intended to support cooperative investigations with the NPS, the development of a new soil map by the Natural Resources Conservation Service, and the All Taxa Biodiversity Inventory. In response to a request by the NPS, we mapped previously unstudied areas, revised the geology where problems existed, and developed...
Tags: Blount County, Blue Ridge province, Cambrian, Chilhowee Group, Conasauga Group, All tags...
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Alaska Division of Geological & Geophysical Surveys (DGGS) has conducted 1:63,360-scale geologic mapping of the Sagavanirktok B-1 Quadrangle (640 square km�equivalent to four 7.5 minute quadrangles). This mapping project reinterprets micropaleontologic correlations for 17 Sagavanirktok Quadrangle wells, and reprocesses data from the one publicly-available seismic line. Surface geologic mapping, subsurface-to-surface stratigraphic age control, and seismic framework are required to reliably decipher the complex geology of this key area of the Brooks Range. Outcrops within the Sagavanirktok B-1 Quadrangle are the closest surface expressions of Prudhoe Bay source and reservoir rocks. This study yields critical petroleum-related...


map background search result map search result map Surficial geology of the Dalton Highway (Itkillik-Sagavanirktok rivers) area, southern Arctic foothills, Alaska Reconnaissance surficial-geologic map of the Sagavanirktok B-1 Quadrangle, eastern North Slope, Alaska Reconnaissance engineering-geologic map of the Sagavanirktok B-1 Quadrangle, eastern North Slope, Alaska Geologic map of the Big Delta A-4 Quadrangle, Alaska Surficial geologic map of the Shaktoolik area, Norton Bay Quadrangle, Alaska USGS 1:24000-scale Quadrangle for Silt, CO 1962 USGS 1:24000-scale Quadrangle for Silt, CO 1962 USGS 1:24000-scale Quadrangle for Silt, CO 1962 USGS 1:24000-scale Quadrangle for Silt, CO 1962 The chemistry of eolian quartz dust and the origin of chert Grain-size analysis of sediment samples collected in July 2016 by the U.S. Geological Survey off Town Neck Beach, Sandwich in Massachusetts, during field activity 2016-037-FA (CSV file and simplified shapefile) Location and grain-size analysis results of sediment samples collected in Long Island Sound, Connecticut and New York, in fall 2017 and spring 2018 by the U.S. Geological Survey, University of Connecticut, and University of New Haven during field activities 2017-056-FA and 2018-018-FA (simplified point shapefile and CSV files) Data for Field Evaluation of the Sequoia Scientific LISST-ABS Acoustic Backscatter Sediment Sensor Grain-size analysis results and locations of sediment samples ollected in Little Egg Inlet and offshore the southern end of Long Beach Island, NJ, during USGS Field Activity 2018-049-FA (simplified point shapefile and CSV files) Database for the Preliminary Geologic Map of the Cherry Hill Quadrangle, Dinwiddie, Sussex, and Greensville Counties, Virginia Database for the Surficial Geologic Map of the Charleston Region, Berkeley, Charleston, Colleton, Dorchester, and Georgetown Counties, South Carolina Database for the geologic map of the Great Smoky Mountains National Park region, Tennessee and North Carolina Geodatabase for the geologic map of the Buckner 7.5-minute quadrangle, Louisa County, Virginia Soil texture and saturated hydraulic conductivity at 1-kilometer and 100-meter resolution for the Contiguous United States based on 30-meter resolution data from the Polaris database Grain-size analysis of sediment samples collected in July 2016 by the U.S. Geological Survey off Town Neck Beach, Sandwich in Massachusetts, during field activity 2016-037-FA (CSV file and simplified shapefile) USGS 1:24000-scale Quadrangle for Silt, CO 1962 USGS 1:24000-scale Quadrangle for Silt, CO 1962 USGS 1:24000-scale Quadrangle for Silt, CO 1962 USGS 1:24000-scale Quadrangle for Silt, CO 1962 Geodatabase for the geologic map of the Buckner 7.5-minute quadrangle, Louisa County, Virginia Database for the Preliminary Geologic Map of the Cherry Hill Quadrangle, Dinwiddie, Sussex, and Greensville Counties, Virginia Grain-size analysis results and locations of sediment samples ollected in Little Egg Inlet and offshore the southern end of Long Beach Island, NJ, during USGS Field Activity 2018-049-FA (simplified point shapefile and CSV files) Location and grain-size analysis results of sediment samples collected in Long Island Sound, Connecticut and New York, in fall 2017 and spring 2018 by the U.S. Geological Survey, University of Connecticut, and University of New Haven during field activities 2017-056-FA and 2018-018-FA (simplified point shapefile and CSV files) Geologic map of the Big Delta A-4 Quadrangle, Alaska Reconnaissance surficial-geologic map of the Sagavanirktok B-1 Quadrangle, eastern North Slope, Alaska Reconnaissance engineering-geologic map of the Sagavanirktok B-1 Quadrangle, eastern North Slope, Alaska Surficial geology of the Dalton Highway (Itkillik-Sagavanirktok rivers) area, southern Arctic foothills, Alaska Surficial geologic map of the Shaktoolik area, Norton Bay Quadrangle, Alaska Database for the geologic map of the Great Smoky Mountains National Park region, Tennessee and North Carolina Data for Field Evaluation of the Sequoia Scientific LISST-ABS Acoustic Backscatter Sediment Sensor Soil texture and saturated hydraulic conductivity at 1-kilometer and 100-meter resolution for the Contiguous United States based on 30-meter resolution data from the Polaris database The chemistry of eolian quartz dust and the origin of chert