Karst Applied Research Studies Through Geologic Mapping (KARST) Project

Shenandoah Task page

Geologic Framework of the Northern Shenandoah Valley Carbonate Aquifer System

The northern Shenandoah Valley of Virginia and West Virginia is an area of expanding population and economic development. To meet the water resource demands, the karst aquifer in the region must be developed.  Local land-use managers are in need of detailed geologic and hydrogeologic information to make informed decisions of source-water protection and land use related to subsidence.  Information used for local studies will be incorporated into a regional study that will help scientists better understand carbonate rock/ground water interactions and karst subsidence development. The KARST project will provide karst and hydrogeologic information that can ultimately be used to guide land-use management and development as related to ground-water resources.

This task will complete geologic mapping for the Winchester 30' X 60' quadrangle by producing detailed geologic maps of the Shenandoah Valley part of the quadrangle and lead to publication of the Winchester sheet. The geologic maps will be used, along with fracture analysis and karst inventories, to look at structural and stratigraphic relations between karst features and geology.  Digital geologic maps will be produced at 1:24,000 scale. In the final year of the project (FY 2007), the Winchester 30' X 60' quadrangle will be compiled from this detailed mapping and from previous mapping from Winchester project of the early and mid 1990's.

The approach to this task
will be geologic mapping that will be used to define geologic formations and describe folds, faults, and joints to investigate their relationship to the carbonate aquifer and surface expression of karst.  Karst features will be accurately located by field examination and be described in their relationship to the geology and hydrogeology to determine geologic controls on karst development.  The rock-fracture network will be defined by measuring fractures (in terms of orientation, persistence, aperture, and intensity) and conduit system to better understand how ground-water moves through the karst system.  Sinkhole distribution analyses will define areas for potential entrance points of contaminants and areas of potential subsidence hazards.

This Task of the KARST Project works in  partnership with the USGS Water Resources Discipline, Virginia Water Science Center (George Harlow, David Nelms)  West Virginia Water Science Center  (Mark Kozar)

This project participates in the Great Valley Water Resources Science Forum

Click here to read fact sheet on the USGS integrated assessment of  the Northen Shenandoah Valley in Virginia and West Virginia (PDF file -- 129KB)

 Location map showing quadrangles in the Senandoah Valley of Virginia and West Virginia and status of geologic mapping by the USGS

Map showing status of USGS geologic mapping in the Shenandoah Valley of  parts of Virginia and West Virginia. Large gray rectangle is the Winchester 30' X 60' quadrangle.

Click on links below for status and availability of geologic maps:

Boyce    Hayfield    Inwood    Middletown    Middleway    Mountain Falls    Stephens City    Stephenson    Whitehall    Winchester24K   Winchester100K