National Coal Resources Data System (NCRDS)

Science Center Objects

The National Coal Resources Data System (NCRDS) began as a cooperative venture between the USGS and State geological agencies in 1975 and focused on the stratigraphy and chemistry of coal.

The current component databases of NCRDS include:

  • USTRAT: Stratigraphic data related to coal (e.g. drill holes, measured sections)
  • USCHEM: Ultimate, proximate, and USGS-generated major-, minor-, and trace-element data for coal samples collected by USGS and States. COALQUAL is a derivation of this database.
  • USCOAL: A historical database of coal resource estimates compiled from publications prior to 1978


Web pages have been developed to query data within both the USCOAL database and a subset of the USCHEM database. The USTRAT database, due to it’s size and complexity, was first made available in 2011 for direct query through web pages. The data is being released after undergoing some basic data quality checks. Data not meeting the checks will be corrected and released in the future. Please check the USTRAT published data release history below to see when new points from various cooperators have been added to the publically accessible USTRAT database. The Energy Resources Program website provides two links that will allow users the ability to query the USTRAT database through both a spatial or tabular interface:

NCRDS USTRAT Spatial Viewer: This viewer allows users to see the location and underlying data associated with NCRDS USTRAT data points. The NCRDS Spatial Viewer was expanded to display data from the USCHEM and USCOAL databases in FY2011.

NCRDS USTRAT Database Query: This webpage allows users to query, browse, and download descriptive stratigraphic data associated with numerous locations throughout the United States.
NCRDS USTRAT Query Help [.pdf]