Data

This dataset consists of a series of rasters covering the conterminous United States. Each raster is a one kilometer (km) grid for 18 selected Census of Agriculture statistics mapped to land use pixels for the time period 1950 to 2012. A supplemental set of 9 statistics mapped at the entire county level are also provided as 1-km rasters. The rasters are posted as ArcGIS grids. The statistics repre

Accurate hydrogen isotopic analysis of halogen- and sulfur-bearing organics has not been possible with traditional high-temperature conversion (HTC) because the formation of hydrogen-bearing reaction products other than molecular hydrogen (H2) is responsible for non-quantitative H2-yields and possible hydrogen isotopic fractionation. The elemental analyzerchromium/high temperature conversion react

An improved understanding of groundwater flow and radionuclide migration downgradient from underground nuclear-testing areas at Pahute Mesa, Nevada National Security Site, requires accurate subsurface hydraulic characterization. To improve conceptual models of flow and transport in the complex hydrogeologic system beneath Pahute Mesa, the U.S. Geological Survey characterized bulk hydraulic propert

The National Water Quality Network (NWQN) for Rivers and Streams includes 113 surface-water river and stream sites monitored by the U.S. Geological Survey (USGS) National Water Quality Program (NWQP). The NWQN represents the consolidation of four historical national networks: the USGS National Water-Quality Assessment (NAWQA) Project, the USGS National Stream Quality Accounting Network (NASQAN), t

In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project of the National Water-Quality Program. One of the major goals of the NAWQA project is to determine how water-quality conditions change over time. To support that goal, long-term consistent and comparable monitoring has been c

In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project of the National Water-Quality Program. One of the major goals of the NAWQA project is to determine how water-quality and ecological conditions change over time. To support that goal, long-term consistent and comparable ecolog

In 1991, the U.S. Geological Survey (USGS) began a study of more than 50 major river basins across the Nation as part of the National Water-Quality Assessment (NAWQA) project of the National Water-Quality Program. One of the major goals of the NAWQA project is to determine how water-quality conditions change over time. To support that goal, long-term consistent and comparable monitoring has been c

This record contains scientific data characterizing soil properties and hydrologic response to rainfall associated with historic rainfall during September 2013 in the Colorado Front Range, USA. Data include soil depth, soil-hydraulic properties of field-saturated hydraulic conductivity and sorptivity, weathered bedrock hydraulic properties including field-saturated hydraulic conductivity and sorp

To indicate that atomic weights of many elements are not constants of nature, in 2009 and 2011 the Commission on Isotopic Abundances and Atomic Weights (CIAAW) of the International Union of Pure and Applied Chemistry (IUPAC) replaced single-value standard atomic weight values with atomic weight intervals for 12 elements (hydrogen, lithium, boron, carbon, nitrogen, oxygen, magnesium, silicon, sulfu

Four-figure standard atomic weights of the chemical elements are shown for 1961, 1975, 1983, 2007, 2009, 2011, 2013, 2015, and the current value for 2016. Values between 1975 and 2015 are only shown when there is a change in value with respect to the previous column.

This product is a series of six national 1-kilometer (km) raster datasets, for five year intervals between 1985 and 2010, representing USGS Water Use "Total Fresh Water Withdrawals", allocated to areas of land use representing anthropogenic use. Pixels representing anthropogenic uses (urban, agriculture, and mining land uses) are derived from the NAWQA Wall-to-wall Anthropogenic Land-use Trends (N

This dataset consists of three raster datasets representing population density for the years 1990, 2000, and 2010. All three rasters are based on block-level census geography data. The 1990 and 2000 data are derived from data normalized to 2000 block boundaries, while the 2010 data are based on 2010 block boundaries. The 1990 and 2000 data are rasters at 100-meter (m) resolution, while the 2010 da