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Environmental risk assessment and decision-making strategies over the last several decades have become increasingly more sophisticated, information-intensive, and complex, including such approaches as expert judgment, cost-benefit analysis, and toxicological risk assessment. One tool that has been used to support environmental decision-making is comparative risk assessment (CRA), but CRA lacks a structured method for arriving at an optimal project alternative. Multi-criteria decision analysis (MCDA) provides better-supported techniques for the comparison of project alternatives based on decision matrices, and it also provides structured methods for the incorporation of project stakeholders' opinions in the ranking...
Categories: Publication;
Types: Citation;
Tags: Adaptive management,
Comparative risk assessment,
Decision analysis,
Risk analysis,
Sediments
In the late 1800s, mills in the Washoe Lake area, Nevada, used elemental mercury to remove gold and silver from the ores of the Comstock deposit. Since that time, mercury contaminated waste has been distributed from Washoe Lake, down Steamboat Creek, and to the Truckee River. The creek has high mercury concentrations in both water and sediments, and continues to be a constant source of mercury to the Truckee River. The objective of this study was to determine concentrations of total and methyl mercury (MeHg) in surface sediments and characterize their spatial distribution in the Steamboat Creek watershed. Total mercury concentrations measured in channel and bank sediments did not decrease downstream, indicating...
Categories: Publication;
Types: Citation;
Tags: Demethylation,
Methyl mercury,
Methylation,
Sediments
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...
Categories: Data;
Tags: Atlantic Ocean,
CMGP,
Cape Cod,
Cape Cod Bay,
Coastal and Marine Geology Program,
This tabular data set represents the percent of surficial materials compiled for two spatial components of the NHDPlus version 2 data suite (NHDPlusv2) for the conterminous United States; 1) individual reach catchments and 2) reach catchments accumulated upstream through the river network. This dataset can be linked to the NHDPlus version 2 data suite by the unique identifier COMID. The source data is the "Map database for surficial materials in the conterminous United States" produced by the United States Geological Survey (USGS, 2009). Units are percent. Surficial materials are defined as an unconsolidated blanket of sediments in which soils commonly are developed. These sediments generally were eroded from underlying...
As part of the hydrodynamic and sediment transport investigations in San Pablo Bay and China Camp Marsh, California, particle size distributions of bed sediments were measured at most instrumented stations and are presented in a comma-delimited values spreadsheet. This portion of the data release presents San Pablo Bay and China Camp Marsh sediment particle size distributions from samples collected during multiple instrument deployments. Users are advised to check the data carefully for sampling time, location, and reference information.
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,
Two marine geological surveys were conducted in Nantucket Sound, Massachusetts, in May 2016 and May 2017 by the U.S. Geological Survey as part of an agreement with the Massachusetts Office of Coastal Zone Management to map the geology of the sea floor offshore of Massachusetts. Samples of surficial sediment and photographs of the sea floor were collected at 76 sampling sites within the survey area, and sea-floor videos were collected at 75 of the sites. The sediment data and the observations from the photos and videos are used to explore the nature of the sea floor; in conjunction with high-resolution geophysical data, the observations are used to make interpretive maps of sedimentary environments and validate acoustic...
Categories: Data;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Atlantic Ocean,
CMHRP,
CZM,
Coastal and Marine Hazards and Resources Program,
MA CZM,
This data release contains the data used to interpret the origin of the shallow lakes in the Khorezm Province, Uzbekistan, and the history of pesticide use around these lakes. The data include 1) lake sediment core data for age dating (cesium-137 and lead-210) for 12 lakes in Uzbekistan, 2) lake sediment core data for loss on ignition (LOI550)for determining organic carbon content of 12 lakes in Uzbekistan, 3) plant pollen occurrence and abundance from lake sediment cores for 6 lakes in Uzbekistan and 4) lake sediment core data for pesticide occurrence of DDT (dichlorodiphenyltrichloroethane) and its degradates and γ-HCH (gamma-hexachlorocyclohexane) for 12 lakes in Uzbekistan, The interpretation of these data will...
Categories: Data;
Types: Citation;
Tags: Age dating (radiometric),
Cesium,
Cesium-137 dating,
Khorezm,
Lead-210 dating,
At the Naturita site in Colorado, USA, groundwaters were sampled and analyzed for chemical composition and by culture and culture-independent microbiological techniques. In addition, sediments were extracted with a dilute sodium carbonate solution to determine quantities of labile uranium within the sediments. Samples from the upgradient portion of the contaminated aquifer, where very little dissolved Fe(II) is found in the groundwater, have uranium content that is controlled by U(VI) adsorption and few metal-reducing bacteria are observed. In the extreme downgradient portion of the aquifer, where dissolved Fe(II) is observed, uranium content of the sediments includes significant quantities of reduced U(IV) and...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Physics and Chemistry of the Earth,
bacteria,
iron,
reduction,
sediments,
At the Naturita site in Colorado, USA, groundwaters were sampled and analyzed for chemical composition and by culture and culture-independent microbiological techniques. In addition, sediments were extracted with a dilute sodium carbonate solution to determine quantities of labile uranium within the sediments. Samples from the upgradient portion of the contaminated aquifer, where very little dissolved Fe(II) is found in the groundwater, have uranium content that is controlled by U(VI) adsorption and few metal-reducing bacteria are observed. In the extreme downgradient portion of the aquifer, where dissolved Fe(II) is observed, uranium content of the sediments includes significant quantities of reduced U(IV) and...
This data release contains the data used to interpret the origin of the shallow lakes in the Khorezm Province, Uzbekistan, and the history of pesticide use around these lakes. The data include 1) lake sediment core data for age dating (cesium-137 and lead-210) for 12 lakes in Uzbekistan, 2) lake sediment core data for loss on ignition (LOI550)for determining organic carbon content of 12 lakes in Uzbekistan, 3) plant pollen occurrence and abundance from lake sediment cores for 6 lakes in Uzbekistan and 4) lake sediment core data for pesticide occurrence of DDT (dichlorodiphenyltrichloroethane) and its degradates and γ-HCH (gamma-hexachlorocyclohexane) for 12 lakes in Uzbekistan, The interpretation of these data will...
Sediment particles can strongly bind metals, effectively repartitioning them from solution to a solid phase. As a result, sediments may accumulate and retain metals released to an aquatic environment. Sediment cores provide a historical record of metal inputs that can reveal anthropogenic influences (Förstner and Wittmann, 1979). Specifically, studies of sediment cores in San Francisco Bay chronicled metal inputs and suggested that legacy contamination can remain a chronic source of metals to the system owing to sediment mixing and redistribution (Hornberger and others, 1999; Van Geen and Luoma, 1999). Metals in sediments also indicate exposure levels to benthic animals through contact with, and ingestion of, bottom...
This dataset consists of values representing the generalized thickness (in feet) of regolith sediments (alluvium, colluvium, and weathered bedrock) overlying well-consolidated bedrock in the Lower Gunnison River Basin in Delta, Montrose, Ouray, and Gunnison Counties, Colorado. Regolith thickness in this dataset was derived from contours presented in the dataset rglth_contours. The U.S. Geological Survey prepared this dataset in cooperation with the Colorado Water Conservation Board.
Recent observations indicate that curious closed depressions in carbonate sediments overlying basement edifices are widespread in the equatorial Pacific. A possible mechanism for their creation is dissolution by fluids exiting basement vents from off-axis hydrothermal flow. Quantitative analysis based on the retrograde solubility of calcium carbonate and cooling of basement fluids during ascent provides an estimate for the dissolution capacity of the venting fluids. Comparison of the dissolution capacity and fluid flux with typical equatorial Pacific carbonate mass accumulation rates shows that this mechanism is feasible. By maintaining sediment-free basement outcrops, the process may promote widespread circulation...
Categories: Publication;
Types: Citation;
Tags: Sediments,
carbonate,
hydrothermal,
pelagic,
solubility,
This data release contains the data used to interpret the origin of the shallow lakes in the Khorezm Province, Uzbekistan, and the history of pesticide use around these lakes. The data include 1) lake sediment core data for age dating (cesium-137 and lead-210) for 12 lakes in Uzbekistan, 2) lake sediment core data for loss on ignition (LOI550)for determining organic carbon content of 12 lakes in Uzbekistan, 3) plant pollen occurrence and abundance from lake sediment cores for 6 lakes in Uzbekistan and 4) lake sediment core data for pesticide occurrence of DDT (dichlorodiphenyltrichloroethane) and its degradates and γ-HCH (gamma-hexachlorocyclohexane) for 12 lakes in Uzbekistan, The interpretation of these data will...
Types: Citation;
Tags: Age dating (radiometric),
Cesium,
Cesium-137 dating,
Khorezm,
Lead-210 dating,
Dam removal is a potentially powerful tool for restoring riverine habitats and communities. However, the effectiveness of this tool is unknown because published data on the effects of dam removal on in-stream biota are lacking. We investigated the effects of a small dam removal on unionid mussels in Koshkonong Creek, Wisconsin (USA). Removal of the dam led to mortality both within the former impoundment and in downstream reaches. Within the former reservoir, mortality rates were extremely high (95%) due to des- iccation and exposure. Mussel densities in a bed 0.5 km downstream from the dam declined from 3.80 ± 0.56 mussels m)2 in fall 2000 immediately after dam removal to 2.60 ± 0.48 mussels m)2 by summer 2003....
Categories: Publication;
Types: Citation;
Tags: mussels,
reservoir,
restoration,
sediments,
siltation,
Many wildlife species ingest soil while feeding, but ingestion rates are known for only a few species. Knowing ingestion rates may be important for studies of environmental contaminants. Wildlife may ingest soil deliberately, or incidentally, when they ingest soil-laden forage or animals that contain soil. We fed white-footed mice (Peromyscus leucopus) diets containing 0-15% soil to relate the dietary soil content to the acid-insoluble ash content of scat collected from the mice. The relation was described by an equation that required estimates of the percent acid-insoluble ash content of the diet, digestibility of the diet, and mineral content of soil. We collected scat from 28 wildlife species by capturing animals,...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: JSTOR,
Journal of Wildlife Management,
contaminants,
diet,
nutrients,
Environmental risk assessment and decision-making strategies over the last several decades have become increasingly more sophisticated, information-intensive, and complex, including such approaches as expert judgment, cost-benefit analysis, and toxicological risk assessment. One tool that has been used to support environmental decision-making is comparative risk assessment (CRA), but CRA lacks a structured method for arriving at an optimal project alternative. Multi-criteria decision analysis (MCDA) provides better-supported techniques for the comparison of project alternatives based on decision matrices, and it also provides structured methods for the incorporation of project stakeholders' opinions in the ranking...
Categories: Publication;
Types: Citation;
Tags: Adaptive management,
Comparative risk assessment,
Decision analysis,
Risk analysis,
Sediments
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,
Coastal and Marine Hazards and Resources Program,
DOI,
Department of the Interior,
We present a numeric grid containing estimates of the thickness of unconsolidated sediments for the western United States. Values for these grids were combined and integrated from previous studies or derived directly from gravity analyses. The grids are provided with 1-km grid-node spacing in WGS84 latitude-longitude coordinates. Detailed information regarding the derivation of these estimates is provided by Shah, A.K, and Boyd, O.S., 2018, Depth to basement and thickness of unconsolidated sediments for the western United States - Initial estimates for layers of the U.S. Geological Survey National Crustal Model: U.S. Geological Survey Open-File Report 2018-1115, https://doi.org/10.3133/ofr20181115.
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