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Groundwater residence times were simulated for the major regional aquifers of the Northern Atlantic Coastal Plain aquifer system from New York to North Carolina using particle tracking in a regional groundwater flow model. Millions of particles were distributed throughout the aquifers of the North Atlantic Coastal Plain in a MODFLOW model with a volume-weighted algorithm, then tracked backwards using MODPATH6 (Pollock, 2012) until termination of their paths at their sources of origin, usually the simulated water table. Particles were tracked under simulated transient hydrologic conditions from the reference time of January 1, 2018 backwards to 1900, then under simulated steady-state conditions prior to 1900 until...
Categories: Data;
Tags: Delaware,
Hydrology,
Maryland,
New Jersey,
New York, All tags...
North Carolina,
Northern Atlantic Coastal Plain,
USGS Science Data Catalog (SDC),
Virginia,
Water Quality,
Water Resources,
age estimation methods,
aquifers,
environment,
groundwater flow,
groundwater quality,
inlandWaters, Fewer tags
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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...
Types: Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Boosted regression tree,
Connecticut,
Cycle 3,
Glacial Principal Aquifer,
Groundwater age, All tags...
Groundwater model,
Hydrology,
Illinois,
Indiana,
Iowa,
Kansas,
Maine,
Massachusetts,
Metamodel,
Michigan,
Minnesota,
Missouri,
Montana,
NAWQA,
Nebraska,
New Hampshire,
New Jersey,
New York,
North Dakota,
Ohio,
Pennsylvania,
Residence time distribution,
Rhode Island,
South Dakota,
USGS Science Data Catalog (SDC),
Vermont,
Washington,
Water Quality,
Wisconsin, Fewer tags
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General Groundwater-Model Construction System Version 0.1 (Genmod0.1) Groundwater residence-time distributions (GRTD) are critical for assessing lag times between activities at the land surface and the emergence of related solutes in the baseflow of streams. However, GRTD can not be measured directly, they must be inferred from an analysis of data using models. Glacial aquifers present challenges to modeling approaches because they are spatially discontinuous and have highly variable properties. An innovative approach developed by the U.S. Geological Survey (USGS) uses machine learning techniques in conjunction with numerical models that results in a rapid and robust way of generating GRTD. The main idea is to...
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Multi Order Hydrologic Position (MOHP) raster datasets: Distance from Stream to Divide (DSD) and Lateral Position (LP) have been produced nationally for the 48 contiguous United States at 30-meter and 90-meter cell resolution for stream orders 1 through 9. These data are available for testing as predictor variables for various regional and national groundwater-flow and groundwater-quality statistical models. For quicker downloads, these data are available here nationally at a 90-meter cell resolution, as well as on the National Spatial Data Infrastructure (NSDI) Node at the higher 30-meter cell resolution ( https://water.usgs.gov/GIS/metadata/styles/landingPage/national_MOHP_Predictor.xml ). The concept...
Tags: Cycle 3,
Groundwater,
Hydrologic Position,
NAWQA,
National Rasters, All tags...
Statistical Predictors,
USGS Science Data Catalog (SDC),
United States,
Water Quality,
Water Quality,
Water Resources, Fewer tags
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