README for U.S. Geological Survey Scientific Investigations Map 3487 TITLE: Geologic Maps of the Stephenson and Winchester Quadrangles, Frederick and Clarke Counties, Virginia, and Inwood and White Hall Quadrangles, Berkeley and Jefferson Counties, West Virginia By: David J. Weary, Daniel H. Doctor, and Randall C. Orndorff ABSTRACT: The study area consists of four contiguous 7.5-minute quadrangles and is located in Frederick and Clarke Counties, Virginia, and Berkeley and Jefferson Counties, West Virginia. The individual quadrangles are Stephenson, Winchester, Inwood, and White Hall. The study area lies within the Great Valley subprovince of the Valley and Ridge physiographic province where about 23,000 feet (ft) (7,000 meters [m]) of Middle Cambrian to Upper Devonian sedimentary rocks are exposed and are overlain by Holocene and older surficial deposits. The area of the four maps is divided into three geologic regions based on the following primary lithologies: (1) Cambrian and Ordovician carbonate rocks of the Great Valley southeast of the North Mountain fault zone and east and west of the core of the Massanutten synclinorium; (2) shale, graywacke, and calcareous shale of the Ordovician Martinsburg Formation of the Great Valley and Massanutten synclinorium; and (3) Ordovician through Devonian clastic rocks and minor limestone and dolostone northwest of and within the North Mountain fault zone. Rocks of all three regions were folded and faulted during the late Paleozoic Alleghanian orogeny (roughly 320 to 250 million years before present). The terrain of this portion of the Great Valley generally is gently to moderately rolling with low local relief with elevations in the study area ranging from about 425 ft (130 m) where Opequon Creek flows out of the eastern edge of the Inwood quadrangle to about 950 ft (290 m) adjacent to Round Hill in the western part of the Winchester quadrangle. Sinkholes and other karst features are common in the carbonate rocks of the Great Valley. The area west of the North Mountain fault zone is underlain by middle Paleozoic strata and consists of a series of ridges and valleys with higher local relief, with elevations ranging from about 785 ft (240 m) in the vicinity of Green Spring in the central part of the White Hall quadrangle to about 1,435 ft (437 m) at the summit of North Mountain in the northeastern part of the White Hall quadrangle. SUPPLEMENTARY INFORMATION: This digital database was compiled in compliance with the USGS National Cooperative Geologic Mapping Program ("GeMS") geologic map database schema (https://ngmdb.usgs.gov/Info/standards/GeMS/) using ArcGIS version 10.7.1. This release is a file geodatabase that contains geologic map feature classes and stand-alone tables. ArcGIS-compatible GIS software is required to use the files of this database. The geodatabase is delivered in a single zipped folder in this release for ease of transfer. The scale of the source maps limits the usable spatial resolution of the database to 1:24,000 scale or greater. Feature classes are symbolized according to the FGDC Digital Cartographic Standard for Geologic Map Symbolization using ArcGIS representation classes where available. For more information about geologic map symbology, see the FGDC Digital Cartographic Standard for Geologic Map Symbolization web page (https://ngmdb.usgs.gov/fgdc_gds/geolsymstd.php). PROJECTION AND DATUM: All data is in North American Datum of 1983, UTM Projection, Zone 17N, units in meters. MAP DOCUMENT:********************************* Contains layer files for this map. This map document was created in ArcGIS 10.7. This file is zipped with the geodatabase (sim3487_database.zip). StWinInWh_VAWV_SIM3487.mxd GEODATABASE: The "GeMS" compliant database contents are described below. SIM3487_database.gdb..............................(Geodatabase) ================================================================================= GeologicMap.............................................(Feature dataset) ========================================================================= GenericPoints..................................(Point feature class with FGDC compliant metadata) FossilPoints..................................(Point feature class with FGDC compliant metadata) Stations..............................(Point feature class with FGDC compliant metadata) OrientationPoints....................................(Polygon feature class with FGDC compliant metadata) OrientationPointLabels......................................(Point feature class with FGDC compliant metadata) CartographicLines..................................(Polyline feature class with FGDC compliant metadata) GeologicLines.....................................(Polyline feature class with FGDC compliant metadata) ContactsAndFaults.................................(Polyline feature class with FGDC compliant metadata) MapUnitOverlayPolys......................................(Polygon feature class with FGDC compliant metadata) MapUnitPolys..................................(Polygon feature class with FGDC compliant metadata) DataSourcePolys................................(Polygon feature class with FGDC compliant metadata) OverlayPolys.......................................(Polygon feature class with FGDC compliant metadata) ========================================================================== DataSources.............................................(Non-spatial table with FGDC compliant metadata) DescriptionOfMapUnits...................................(Non-spatial table with FGDC compliant metadata) GeoMaterialDict.........................................(Non-spatial table with FGDC compliant metadata) Glossary................................................(Non-spatial table with FGDC compliant metadata) METADATA: Metadata files are valid for both the geodatabase feature classes and open-access shapefiles. Metadata is contained in a single zipped folder (sim3487_metadata.zip). ================================================================================= GeologicMap.xml..............................................(Feature Dataset level FGDC compliant metadata) CartographicLines.xml........................................(Feature class level FGDC compliant metadata) ContactsAndFaults.xml........................................(Feature class level FGDC compliant metadata) DataSourcePolys.xml..........................................(Feature class level FGDC compliant metadata) FossilPoints.xml.............................................(Feature class level FGDC compliant metadata) GenericPoints.xml............................................(Feature class level FGDC compliant metadata) GeologicLines.xml............................................(Feature class level FGDC compliant metadata) MapUnitOverlayPolys.xml......................................(Feature class level FGDC compliant metadata) MapUnitPolys.xml.............................................(Feature class level FGDC compliant metadata) OrientationPoints.xml........................................(Feature class level FGDC compliant metadata) OrientationPointLabels.xml....................................(Annotation feature class FGDC compliant metadata) OverlayPolys.xml.............................................(Feature class level FGDC compliant metadata) Stations.xml.................................................(Feature class level FGDC compliant metadata) DataSources.xml..............................................(Non-spatial table FGDC compliant metadata) DescriptionOfMapUnits.xml....................................(Non-spatial table FGDC compliant metadata) GeoMaterialDict.xml..........................................(Non-spatial table FGDC compliant metadata) BASEMAP: These georegistered files are contained in two subdirectories within a single zipped folder (sim3487_basemaps): /Raster24kTopo/ BaseMapREADME InwoodDRG.jpg StephensonDRG.jpg WhiteHallDRG.jpg WinchesterDRG.jpg /RasterLidarDerived LidarBaseMapREADME InwoodTPI_HS.png StephensonTPI_HS.png WhiteHallTPI_HS.png WinchesterTPI_HS.png OPEN-ACCESS VERSIONS: ************************************* To improve access to this product, open-access versions of these data are included with this release. One folder is available; sim3487_openaccess.zip contains all database elements as shapefiles with corresponding tables presented as Excel files (.xls) and (or) text files (.txt).