Filters: Tags: sedimentology (X)
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Acoustic seabed classification (ASC) is an important method for understanding landscape-level physical and biological patterns in the aquatic environment. Bottom habitats in the Laurentian Great Lakes are poorly mapped to date, and will require a variety of contributors and data sources to complete. We repurposed a long-term split-beam echosounder dataset gathered for purposes of fisheries assessment to estimate lakebed properties utilizing unsupervised classification of echo return data. We extracted first echo properties and analyzed lakebed hardness and roughness to define and map three statistically supported lakebed classes revealed through cluster analysis. Our results indicate coherent and logical class boundaries,...
This dataset accompanies planned publication 'Detrital record of the Late Oligocene – Early Miocene mafic volcanic arc in the Southern Patagonian Andes (~51°S) from single-clast geochronology and trace element geochemistry'. The Ar/Ar data is for samples that record the detrital sedimentary record of the basin. The geochronology provides time constraints for the sedimentation studied in the manuscript. Samples were collected from the Magallanes-Austral Basin, and collection was supervised by Julie Fosdick, who sent them to the USGS for Ar/Ar analysis.
Variability in sediment properties with depth and the thickness of individual sedimentary layers are critical determinants of seabed acoustic response. The New England Mud Patch (NEMP), located south of Cape Cod, is an unusual feature on the U.S. Continental Shelf in that it is composed of fine-grained sediment layers containing a relatively-homogeneous mix of sand, silt, and clay-sized particles bounded by more typical sandy shelf sediments. The unique characteristics and nature of this deposit is due to a derivation of sediments that have been transported to, and deposited in, a basal bowl-shaped depression since the last glacial maximum. Ninety-two piston, vibra-, and gravity cores with a maximum length of 8.2...
This section of the data release includes core images in the format of photos (JPG) that have been compressed into a zipped file (2018LakePowellCoring_CorePhotos.zip). It is Part 4 (of four) in this data release and contains images of the cleaned archival half from split cores as they appeared immediately after splitting (late March and early April 2019). Each photo includes a ruler (in centimeters) and X-Rite ColorChecker Classic color correction card that may be used for corrections. Drillhole information, such as location and total recovery, are outlined in “Part 1 – Drillhole information from the 2018 coring project in Lake Powell, Utah” (2018LakePowellCoring_DrillholeInfo.csv) of this data release. Each drillhole...
This data release provides digital flight line data for a high-resolution airborne magnetic and radiometric survey over Charleston, South Carolina and the surrounding region. These data were collected to better understand earthquake hazards in the Charleston seismic zone by imaging structural features in the crystalline basement and to image heavy mineral sands containing titanium, zirconium, and rare earth elements using radiometric data (gamma spectrometry), which is sensitive to thorium in monazite. This survey represents a collaborative effort by the U.S. Geological Survey (USGS) Earthquake Hazards Program, Mineral Resources Program, National Cooperative Mapping Program, and Earth Mapping Resource Initiative...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Berkeley County,
Charleston,
Charleston County,
Clarendon County,
Colleton County,
Suspended-sediment transport is a critical element governing the geomorphology of tidal marshes and estuaries. Marsh elevation, relative to sea level, is maintained by both organic material and the deposition of inorganic sediment. Additionally, horizontal marsh extent is altered by lateral erosion and accretion. In wetlands within and near Grand Bay National Estuarine Research Reserve, parts of the salt marsh are eroding relatively rapidly. To understand the connection between sediment fluxes and these processes, the U.S. Geological Survey made oceanographic and water-quality measurements from August 2, 2016, to January 28, 2017, to quantify suspended-sediment concentration and sediment transport in tidal channels...
Categories: Data;
Tags: Bayou Heron,
Bayou Middle,
Geomorphology,
Grand Bay,
Grand Bay National Estuarine Research Reserve,
Twenty-four piston cores (and associated trigger cores) were collected from the source zone of the Currituck Landslide Complex and upper slope adjacent to Baltimore Canyon by the U.S. Geological Survey and the University of Rhode Island Department of Ocean Engineering during an eight-day cruise aboard the R/V Hugh R. Sharp in September/October of 2012. These cores were analyzed for evidence of seafloor mass transport processes, with an emphasis on constraining the age and shallow stratigraphy of the landslide complex. Sedimentological and geotechnical characterization of the cores was carried out through whole core imaging and description, followed by analysis of discrete samples at the USGS Woods Hole Coastal and...
The U.S. Geological Survey provides a wide range of scientific information to an even wider group of stakeholders. Understanding what capacities are needed and if and or where these capacities exist across the USGS landscape is critical in moving science to the next level of use, implementation, and visualization. The concept behind the groups organized to conduct and interpret the survey that collected these data took advantage of the USGS’s position as a science organization with expertise spanning a wide range of science disciplines, stakeholders, and responsibilities. A survey was conducted of USGS employees (Sep 20-Nov 20) to get a current sample of the capacities that exist across the USGS.
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Aquatic Biology,
Botany,
Climatology,
Ecology,
Economic Geology,
The mid-Piacenzian is known as a period of relative warmth when compared to the present day. A comprehensive understanding of conditions during the Piacenzian serves as both a conceptual model and a source for boundary conditions as well as means of verification of global climate model experiments. These data are provided as digital representations of mid Pliocene boundary conditions stored in NetCDF format for use with climate models.
Denali National Park and Preserve (DENA), located in central Alaska, is home to iconic and dynamic landscapes surrounding the tallest mountain range in North America, the Alaska Range. DENA preserves over 6 million acres of wild land that provides opportunities for recreation, subsistence hunting and gathering, preservation of cultural resources, and scientific research. Despite its size and popularity, DENA has only one road—the dead-end, 92-mile Denali National Park Road (hereafter referred to as the Park Road). The Park Road is mostly gravel; only the first 15 miles are paved. It is the only access for most DENA infrastructure, including visitor centers, staff facilities, campgrounds, and businesses. The Park...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Alaska,
Alaska Range,
Browne glaciation,
Cantwell Basin,
Cantwell Formation,
Lake-bottom sediment and associated quality-control samples were collected in August 2020 from one coring location (U.S. Geological Survey station 413756070321301, ASHUMET POND, MASHPEE MI-ASHPD-0011) in Ashumet Pond downgradient from a former fire-training area on Cape Cod, Massachusetts. The core was collected to determine if per- and polyfluoroalkyl substances (PFAS) were present in the bottom sediments of a lake known to have elevated concentrations of PFAS in surface water and groundwater (Tokranov and others, 2021), and whether the sediments could act as a continuous source of PFAS to the lake. Processing the sediment core entailed collection of discrete samples at intervals ranging from 1-5 centimeters (cm)...
Categories: Data,
Data Release - Revised;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Cape Cod,
Eastern United States,
Environmental Health,
Falmouth,
Hydrology,
The San Juan River is a major water source for communities in the Four Corners region of the United States (parts of Colorado, Arizona, New Mexico, Utah) and is a vital source of water for the Navajo Nation. The Navajo Nation Environmental Protection Agency (NNEPA) periodically samples surface water on the Navajo Nation and has found that some elements exceed NNEPA surface water standards (the upper limits of an element for consumption or other use of water). Constituents of concern are substances that could be harmful if present in sufficient quantities, and it is important to monitor the concentrations of these substances in the environment. In the San Juan River, constituents of concern include metals detected...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Arizona,
Colorado,
Four Corners,
Geochemistry,
Mineral Resources,
Experimental modelling of an aggrading braided river has allowed investigation of the relationship between the frequency of channel avulsion (Af), the duration of time that the braidplain is occupied by flow, the spatial pattern of braidplain sedimentation and how these respond to a change in sediment supply (Ss). Model results demonstrate a strong, positive relationship between Ss and Af and that there is no downstream change in Af over the short braidplain distances (ca 100 m) modelled herein. Although Af is strongly dependent on Ss, the degree of channel switching does not influence the rate, or spatial pattern, of braidplain sedimentation. All experiments used a single, central input for water and sediment,...
The Permian Cedar Mesa Sandstone of south-east Utah is a predominantly aeolian succession that exhibits a complex spatial variation in sedimentary architecture which, in terms of palaeogeographic setting, reflects a transition from a dry erg centre, through a water table-controlled aeolian-dominated erg margin, to an outer erg margin subject to periodic fluvial incursion. The erg margin succession represents a wet aeolian system, accumulation of which was controlled by progressive water table rise coupled with ongoing dune migration and associated changes in the supply and availability of sediment for aeolian transport. Variation in the level of the water table relative to the depositional surface determined the...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Aeolian,
Sedimentology,
Utah,
erg margin,
interdune,
These data were compiled for analyses of sediment transport within the Chippewa River, WI. Objective(s) of our study were to determine sand loads contributed by the Chippewa River to the Mississippi River. These data include physical suspended-sediment samples, acoustical suspended-sediment measurements, acoustical suspended-sediment loads, quasi-continuous measurements of bed-elevation, multibeam sonar survey data, and longitudinal profiles of the bed-elevation at certain locations. These data were collected in the Chippewa River in 2018 and 2019. Acoustical suspended-sediment data also include data from March and April 2020. These data were collected by the USGS Grand Canyon Monitoring and Research Center and...
This digital dataset release of the La Junta, Colorado and Kansas quadrangle is composed of previously published elevation contours, structure contours on the limits of the Morrison, Dakota, and Purgatorie Formations, and geologic formational data. The digitizing of this map is to provide a more accessible dataset to be available for public usage. The original dataset was part of an eight-part series of maps in Colorado and Kansas, this map modified in part by reconnaissance by G.R. Scott in 1968. The entirety of this dataset includes both spatial and non-spatial data held in a singular, GeMS compliant geodatabase. This geodatabase includes a geologic map, geologic map feature class holding contact and fault lines,...
Categories: Data;
Types: ArcGIS REST Map Service,
ArcGIS Service Definition,
Downloadable,
Map Service;
Tags: Big Basin Formation,
Colorado,
Cretaceous,
Dakota Sandstone,
Dockum Group,
Post-Eocene (predominantly Pliocene) continental sedimentary rocks of the Sacramento Valley, CA are up to 1,200 m thick beneath the valley. These rocks contain most of the fresh ground water in the valley, forming a key component of the total water budget for the valley. A 1974 study by the U.S. Geological Survey was an early attempt to develop detailed knowledge of the subsurface geology of the Sacramento Valley. The study delineated the configuration of the base post-Eocene continental sedimentary rocks of the Sacramento Valley and mapped the thickness of those deposits. This digital dataset contains spatial datasets corresponding to the contoured base and thickness of the post-Eocene continental sedimentary rocks...
Categories: Data;
Tags: California,
Central Valley aquifer system,
Sacramento,
Sedimentology,
Stratigraphy,
Salt Marsh Turbidity at Mockhorn Island, VA; Plum Island, MA; York River, VA; and Altamaha River, GA
We measured turbidity along transects from channel to marsh interior for 4 sites along the east coast of the United States at: Mockhorn Island, on the Eastern Shore of VA, USA; Plum Island in MA, USA; Goodwin Islands on the York River, VA USA; and the Altamaha River estuary, in GA, USA.
This data release contains spatial data associated with the bathymetric survey and sedimentation analysis of Lago Carite in January 2018. During January 23–30, 2018, the U.S. Geological Survey, in cooperation with the Puerto Rico Electric Power Authority, conducted a bathymetric survey of Lago Carite primarily to update estimates of the contemporary reservoir storage capacity and sedimentation rate. Previously designated transect lines were surveyed by using a depth sounder coupled to a differential geographic positioning system to generate a bottom contour map and, ultimately, the stage-storage relation for Lago Carite. This data release consisted of three items: bathymetric contours, water-depth data points and...
This data release provides digital flight line data for a high-resolution airborne magnetic survey over parts of Montana in the vicinity of the Boulder Batholith. The airborne survey was jointly funded by the Earth Mapping Resources Initiative and Kennecott Exploration Company. The survey was designed to meet complementary needs related to geologic mapping and characterization of mineral resource potential. A total of 34,041-line km of magnetic and radiometric data were acquired over an irregular-shaped area of 6178 km2. Data were collected from a helicopter flown at a nominal terrain clearance of 100 meters (m) above topography along E-W flight lines spaced at 200 m intervals. Tie lines were flown in an N-S direction...
Categories: Data;
Types: Downloadable,
GeoTIFF,
Map Service,
Raster;
Tags: AASG,
Aeromagnetic survey,
Airborne geophysical survey,
Association of State Geologists,
Boulder Mountains,
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