Coal Mines

This layer shows the location and production of coal mines within the United States

Locations of Primary Care Physicians

This layer displays the locations of all primary care physicians with a CMS National Provider Identifier (NPI). Primary care physicians are those MDs or DOs specializing in family practice, general practice, pediatric medicine, or internal medicine. Data are from the Centers for Medicare and Medicaid Services (CMS) August 2019 National Provider Identifier (NPI) downloadable file.

Coal Fields

This data set shows the coal fields of Alaska and the conterminous United States. Most of the material for the conterminous United States was collected from James Trumbull’s “Coal Fields of the United States, Conterminous United States” map (sheet 1, 1960). The Gulf Coast region was updated using generalized, coal-bearing geology obtained from State geologic maps. The Alaska coal fields were collected from Farrell Barnes’s “Coal Fields of the United States, Alaska” map (sheet 2, 1961).

Wind Turbine Density

This layer was created using point data of Wind Turbine locations within the U.S. from USGS. Density was calculated using a circular neighborhood of 1 mile and each cell is 1 square mile in area.

Crude Oil Pipelines

This layer represents crude oil pipelines throughout the U.S. and part of Canada.

Oil and Natural Gas Well Density

This layer was created using point data of Oil and Natural Gas wells in the United States. An Oil and Natural Gas Well is a hole drilled in the earth for the purpose of finding or producing crude oil or natural gas; or producing services related to the production of crude or natural gas. Density was calculated using a circular neighborhood of 1 mile and each cell is 1 square mile in area.

Watershed Boundary Dataset, 8-Digit Hydrologic Units

The 8-Digit Hydrologic Units, a component of the Watershed Boundary Dataset (WBD), depict the fourth level hydrologic subdivision of the United States. A hydrologic unit can accept surface water from upstream drainage areas and may define a drainage area with single or multiple outlet points. An 8-digit hydrologic unit, or sub-basin, is a common management unit for water resource planning and analysis. There are 2,362 8-digit hydrologic units with an average size of 1,783 square miles (4,619 sq. km.).