Data

County Geologic, Mined Land Inventory Maps

Thumbnail of South River-Annapolis Quadrangle

MGS is developing digital geologic maps, particularly for use in geographic information systems (GIS). These maps are available for purchase on CD-ROM, and printed versions are available separately. Print versions are full-color, full-scale paper plots at a resolution of 300 dpi (generally about 34 x 44 inches in size). To purchase copies of maps (paper or CD-ROM) contact the Publications Office with the County Name from the chart below. If you are interested in our traditional paper map products see the Maps section or the online List of Publications for ordering information and prices.

All maps and geospatial data are projected in the Maryland State Plane coordinate system (Lambert conformal conic projection) North American Datum 1983 (NAD83) meters. The geologic information for the county-scale maps is compiled at a scale of 1:62,500 (roughly one inch equals a mile). The topographic and hydrographic base map layers for this digital series were developed from U.S. Geological Survey 30 x 60-minute topographic series (1:100,000). Contour intervals are in meters. As shown on the county series, these base layers are enlarged to 1:62,500.

The CDs contain a copy of the pertinent map(s) in Adobe Acrobat PDF format. If you have access to a large-format color printer you could print these maps at full scale from the PDF file. The CDs also contain files for use in GIS. The GIS files were created using ESRI’s ArcGIS software (version 8.2 or higher). ArcGIS coverages as well as interchange files (.e00) are provided for the vector layers, which include the geologic layers and some or all of the base map layers. Some maps contain raster images for some base map components; rasters are in TIFF format. The full written descriptions of the geologic units are provided in a text file format in addition to being on the PDF. Text files can be read by any text reader (such as Notepad, Wordpad, or Microsoft Word). Metadata files (information about the map and how the layers were made) are provided as part of the digital layers and as separate text files.

Information about ESRI’s ArcExplorer software is provided on the CD but must be downloaded separately. ArcExplorer is ESRI's free GIS data reader software (for use with coverages, shapefiles, images). Visit the ESRI web site at http://www.esri.com/software/arcexplorer/index.html to download the software or get more information about this program.

County, Version, and Maps Included			Formats			Release Date
County, Version, and Maps Included
Charles County
	CHGEO2003.1	Geologic map (pdf map is contained in 2 separate files)	1 2	$10.00	All maps on one CD-ROM $25.00	2003
	CHMINE2003.1	Mined Land Inventory (historic and 2002 data)		$10.00		2003
	CHTK2003.1	Thickness of Surficial Sand-and Gravel-Bearing Units		$10.00		2003
	The Charles County digital series includes a digital version of the county geologic map by McCartan (1989), a mined land inventory map (historic and 2002 data), and a thickness contour map of the surficial sand- and gravel-bearing units in the county. Digital components for all three of the maps are provided together on one CD-ROM. Historic data shown on the mined land inventory map was excerpted from the “Sand and Gravel Resources and Mined Land Inventory Map” (blueline) by Brooks (1985).
Prince George’s County						Release Date
	PGGEO2003.2	Geologic map		$10.00	All maps on one CD-ROM $25.00	2006
	PGMINE2003.2	Historic mined land inventory		$10.00		2006
	PGMINV2006.1	Mined land inventory 2006		$10.00		2006
	The Prince George’s County digital series includes a digital version of the county geologic map by Glaser (previously unpublished), an historic mined land inventory map (modified from Kuff, 1980) and a mined land inventory 2006 (completed in cooperation with the Maryland Department of the Environment). Digital components for these maps are on one CD-ROM. The Prince George’s County geologic map replaces the version by Cloos (1951), which is out-of-print. The geologic map also includes a layer showing the distribution of a silt-loam soil with hardpan as mapped by Hack (1977) within the Upland deposits.