Filters: partyWithName: James E Reddy (X)
26 results (42ms)|
Filters
Date Range
Extensions Types
Contacts
Categories Tag Types
|
This data release contains input data used in model development and TIF raster files used to predict the probability of high arsenic (As) and high manganese (Mn) in groundwater within the glacial aquifer system in the northern United States. Input data include measured As and Mn concentrations at groundwater wells, and associated predictor variable data. The probability of high As and high Mn was predicted using boosted regression tree methods using the gbm package in R version 4.0.0. The response variables for individual models were the occurrence of: (1) As >10 µg/L, and (2) Mn >300 µg/L. Water-quality data were compiled from three sources, as described in Wilson and others (2019): a compilation of data from numerous...
A digital representation of closed depression features overlying and adjacent to New York’s carbonate-bedrock aquifers. Includes closed depressions that are both natural and anthropogenic in origin. The features were derived from a digital contour database obtained from https://topotools.cr.usgs.gov/contour_data.php. The original contour dataset was generated from the National Elevation Dataset (NED) and the National Hydrography Dataset (NHD) in a fully automated process. The process is described in U.S. Geological Survey Scientific Investigations Report 2012–5167.
A digital representation of a glacial aquifer map for the northeastern United States (Kontis and others, 2004; http://pubs.er.usgs.gov/publication/pp1415C; Plate 3) has been prepared by staff of the U.S. Geological Survey. Aquifer data was digitally compiled from a georeferenced version of Plate 3, along with supplemental aquifer maps that covered portions of the northeast.
Background: A sequence of gently dipping carbonate bedrock - the Bertie Formation, Akron Dolostone, and Onondaga Limestone crop out along a 2- to5-mile wide band in western and central New York. These bedrock units trend east-west for 250 miles across the State and form extensive carbonate-bedrock aquifers which transmit and yield water from solution-enlarged fractures, bedding planes, and other openings (Olcott, 1995). Bedding planes or sub-horizontal fractures typically are the most enlarged and important water conduits. Karstic features such as sinkholes, swallets, solution channels, and caverns can locally transmit large amounts of surface water into the ground where the groundwater can move quickly and over...
Categories: Data,
Project;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Aquifer Mapping,
Aquifer Mapping,
Aquifer Mapping,
Basin & Hydrogeologic Characterization,
Basin & Hydrogeologic Characterization,
This data release contains input data used in model development and TIF raster files used to predict the probability of low dissolved oxygen (DO) and high dissolved iron (Fe) in groundwater within the glacial aquifer system in the northern continental United States. Input data include measured DO and Fe concentrations at groundwater wells, and associated predictor variable data. The probability of low DO and high Fe was predicted using boosted regression tree methods using the gbm package in R (v. 4.0.0) in RStudio (v. 1.2.5042). The response variables for individual models were the occurrence of: (1) DO ≤0.5 mg/L, (2) DO ≤2 mg/L, and (3) Fe >100 µg/L. Water-quality data were compiled from three sources, as described...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Connecticut,
Geochemistry,
Hydrology,
Idaho,
Illinois,
A boosted regression tree (BRT) model was developed to predict pH conditions in three-dimensions throughout the glacial aquifer system (GLAC) of the contiguous United States using pH measurements in samples from 18,258 wells and predictor variables that represent aspects of the hydrogeologic setting. Model results indicate that the carbonate content of soils and aquifer materials strongly controls pH and when coupled with long flow paths, results in the most alkaline conditions. Conversely, in areas where glacial sediments are thin and carbonate-poor, pH conditions remain acidic. At depths typical of drinking-water supplies, predicted pH > 7.5 – which is associated with arsenic mobilization – occurs more frequently...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Boosted regression trees,
Calcite saturation index,
Connecticut,
Geochemistry,
Geochemistry,
The Lithologic Logs dataset includes state well records, and the well logs were standardized so that the lithologic information used a consistent terminology by Bayless and others (2017). The dataset contains 1,565,051 records, of which 746,568 are for wells that are used for withdrawing water.
Residence time distribution (RTD) is a critically important characteristic of groundwater flow systems; however, it cannot be measured directly. RTD can be inferred from tracer data with analytical models (few parameters) or with numerical models (many parameters). The second approach permits more variation in system properties but is used less frequently than the first because large-scale numerical models can be resource intensive. With the data and computer codes in this data release users can (1) reconstruct and run 115 General Simulation Models (GSMs) of groundwater flow, (2) calculate groundwater age metrics at selected GSM cells, (3) train a boosted regression tree model using the provided data, (4) predict...
The Sediment and Aquifer Characteristics dataset includes two, grid-based polygon feature classes. The first class uses a five-kilometer grid to show the density of lithologic logs available for analysis. The second class contains attributes that characterize either Quaternary sediment in the glaciated conterminous United States or aquifer material within it. The attributes are derived from lithologic logs obtained from boreholes and wells. The polygons were delineated by a constrained, kriging-based interpolation based on the distribution of map units in the source Surficial Geologic Units dataset using a grid-based algorithm to interpolate between the point data, as defined in the processing steps.
The Glacial Environments and Surficial Sediments geodatabase (GESS) data includes a polygon file with multiple attributes which describe the lithology, geomorphology, and related depositional environment of Quaternary-age surfical sediments in the glaciated conterminous United States. These attributes include: the map unit (GESS_MU), a geomorphic modifier (GESS_Modifier), a sediment stratification indicator (SedStrat), and a a sediment texture classification (Texture6). Possible GESS_MU values include: alluvial sediment, colluvial sediment, eolian sediment, lacustrine sediment, marine sediment, organic sediment, outwash, ice-contact deposits, island, residual soils, soliflucted sediment, till, bedrock, fill, and...
Widespread nitrate contamination of groundwater in agricultural areas poses a major challenge to sustainable water resources. Efficient analysis of nitrate fluxes across large regions also remains difficult. This study introduces a method of characterizing nitrate transport processes continuously across regional unsaturated zones and groundwater based on surrogate, machine-learning metamodels of an N flux process-based model. The metamodels used boosted regression trees (BRTs) to relate mappable variables to parameters and outputs of a “vertical flux method” (VFM) applied in the Fox-Wolf-Peshtigo (FWP) area in Wisconsin. In this context, the metamodels are upscaling the VFM results throughout the region, and the...
The bedrock geology for the Glacial Environments and Surficial Sediments (GESS) geodatabase is an amalgamation of several “Integrated Geologic Map Databases for the United States” (Dicken and others, 2008; Ludington and others, 2007; Nicholson and others, 2007-1,-2,-3; Stoeser and others, 2007). Using the LITH62 and LITH62MINO attribute values from that series of maps and the associated lithclass 6.2 code text descriptions from the geodatabase, spatial elements of that geodatabase were grouped. A new GESS attribute was created, “Litho_class,” and each spatial element was given a Litho_class value of non-carbonate sedimentary rock, carbonate rock, non-carbonate metamorphic rock, volcanic rock, plutonic rock, or unconsolidataed...
Chemical data from 43,334 wells were used to examine the role of land surface-soil-aquifer connections in producing elevated manganese concentrations (>300 µg/L) in United States (U.S.) groundwater. Elevated manganese and dissolved organic carbon (DOC) concentrations were associated with shallow water tables and organic-carbon rich soils, suggesting soil-derived DOC supported manganese reduction. Manganese and DOC concentrations were higher near rivers than farther from rivers, suggesting river-derived DOC also supported manganese reduction. Anthropogenic nitrogen may also affect manganese concentrations in groundwater. In parts of the northeastern U.S. containing poorly buffered soils, ~40% of the samples with...
Categories: Data;
Tags: Environmental Health,
Hydrogeology,
NAWQA,
National Water Quality Program,
USGS Science Data Catalog (SDC),
A digital representation of the study area boundary adopted for the GIS analyses. The boundary was created by intersecting an index of USGS 1:24,000-scale, 7.5-minute quadrangle maps with data containing selected bedrock geologic units from U.S. Geological Survey Data Series 1052. The final study area boundary covers more than 20,000 square miles, amounting to 38 percent of New York State and transecting 42 counties.
The New York State Departments of Environmental Conservation and Health are concerned about groundwater contamination in the carbonate-bedrock aquifers with the potential to host karst features throughout New York State, especially relating to the unintended introduction of chemical or agricultural contamination into these aquifers. USGS Scientific Investigations Report, SIR 2020-5030 (Kappel and others, 2020), provides local and State regulators and the public the information needed to determine the extent of carbonate bedrock in New York, the associated environmental impacts of karst, and the means to protect New York’s karst water resources. The four geodatabases presented in this data release were compiled...
Hydrogeologic Recharge Settings of the Carbonate-Bedrock Aquifer in Genesee County, Western New York
Problem - The New York State Departments of Environmental Conservation (NYSDEC) and Health (NYSDOH) are concerned about Problem - The New York State Departments of Environmental Conservation (NYSDEC) and Health (NYSDOH) are concerned about ground-water contamination in the carbonate-bedrock aquifers, especially relating to the inadvertent introduction of volatile organic compounds (VOCs) and manure to these aquifers. Groundwater can flow very quickly with minimal filtration or adsorption through solution-widened fractures in carbonate-bedrock aquifers. Therefore, large amounts of water and associated contaminants can move long distances, sometimes in short periods of time, and affect large areas. If these underground...
Categories: Data,
Project;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Aquifer Mapping,
Aquifer Mapping,
Aquifer Mapping,
Basin & Hydrogeologic Characterization,
Basin & Hydrogeologic Characterization,
This data release contains the results of an isotopic mass balance approach to provide an estimate of the long-term average isotope ratios of NWM streamflow for the summer season (JJA) between 2000 and 2019 in the Western United States. The NWM-estimated long-term average isotope ratios are compared directly to 6426 stream stable isotope observations in 995 unique catchments. Quantified similarities and differences, in the form of p-values, provide useful information about important hydrologic processes. Significant p-values mean that the observed isotope ratio differs from the long-term average mass balance calculated isotope ratios and indicates that flows may be influenced by processes that are not accounted...
Categories: Data;
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Arizona,
California,
Colorado,
Hydrology,
Idaho,
The Groundwater Usage for Public Supply dataset contains attributes pertaining to groundwater use in the glaciated conterminous United States summarized by county. The attributes were computed from total groundwater usage by county compiled by Maupin and others (2010), and from inventories of water-use records for 71,267 public water-supply systems by Buchwald and others (in press). Source aquifers (Quaternary sediments or bedrock) were assigned for the public water-supply systems based on reported data (e.g., well construction records, aquifer delineation maps), or based on well depth and the Quaternary sediment thickness. Water usage rates are reported on an average annual, areal basis in units of millimeters...
A digital representation of closed depression features overlying and adjacent to New York’s carbonate-bedrock aquifers. Includes closed depressions that are both natural and anthropogenic in origin. The features were derived from Digital Raster Graphic (DRG) images of scanned U.S. Geological Survey 1:24,000-scale topographic maps. A DRG is a scanned image of a U.S. Geological Survey topographic map that can be added as a background layer in a GIS. The closed depressions inventoried using DRGs represent features that were not included in the Digital Contour Database. The features were inventoried as points.
The Hydrogeologic Terranes dataset includes separate polygon and line feature classes. The polygon feature class divides the glaciated United States into seventeen distinct terranes using a geologically based approach. Each terrane contains Quaternary sediment that is derived from a common depositional history and can be characterized by texture and thickness. Delineation of hydrogeologic terranes was based on an interpretation of existing geologic mapping of surficial and Quaternary deposits, and thickness of unconsolidated material. Overall thickness of Quaternary sediment was used to qualitatively rank the generalized complexity of geologic framework in each terrane: "lower" complexity (assigned a terrane code...
|
|
