Maryland Department of Natural Resources

MGS maps are now viewable on the interactive MapView interface of the USGS National Geologic Map Database (NGMDB)

February 2, 2017

It is now easier to browse and view geologic maps in Maryland with the recent addition of MGS maps to the interactive MapView interface of the USGS National Geologic Map Database (NGMDB).

Visit the website here:

About the NGMDB

The National Geologic Map Database (NGMDB) is a Congressionally mandated project led by the U.S. Geological Survey and Association of American State Geologists. The purpose is to build a national archive of standardized geologic map information. This national archive is “virtual” – you can access it through a searchable catalog that contains information on over 88,000 geoscience maps and reports dating back to the 1800's, with links to hundreds of publishers.

Standardization of geologic maps – this is a gradual process that involves all the Nation’s geological surveys, and other producers and users of maps. Resources (including the U.S. Geologic Names Lexicon) and draft guidelines and standards are available at the NGMDB site.

Geologic mapping is done for many different purposes including, for example: individual, detailed studies of a local area in order to precisely assess the geologic hazards; and systematic, quadrangle-by-quadrangle mapping of a region that improves our estimates of the Nation’s resources. Beginning in the 1800’s, geologic mapping has been conducted for these various purposes, by Federal, State, University, and private entities. The result in an information-rich mosaic of maps at different scales, funded for various specific purposes, using the technology and science available at the time of mapping.

MapView shows a significant part of the NGMDB’s national archive of geoscience information – that is, the systematic, regional mapping of the bedrock and surficial deposits. Other geologic maps and related information (geologic structure, hazards and resources, and so forth) will be included in later versions of the Viewer. As you can see, maps of many States remain to be added – we invite you to explore the Nation’s geologic mapping heritage, and give us your ideas on how to improve this archive.