GEOLOGY OF THE MOOREFIELD 7 1/2 MINUTE QUADRANGLE, WESTERN HARDY COUNTY, WEST VIRGINIA

The Moorefield quadrangle is located in the west-central Valley and Ridge province in Hardy County, eastern West Virginia. The complexly folded and faulted strata here range in age from Upper Silurian Tonoloway Limestone to Lower Mississippian Pocono Sandstone. The major structures from northwest to southeast are Kessel anticline, Middle Mountain syncline, southern plunge-out of Broadtop anticline, Town Hill syncline, Elkhorn Mountain anticline and Whip Cove syncline. Kessel anticline and southern Broadtop anticline were generated by folding and faulting above an Upper Ordovician (i.e. Martinsburg Formation) detachment horizon. Middle Mountain syncline separates these two folds. Elkhorn Mountain anticline was generated by ramping from a lower detachment horizon (i.e. Lower Cambrian Waynesboro Formation) to the Martinsburg Formation. Whip Cove syncline, southeast of the Elkhorn structure, merely formed as a passive structure between Elkhorn Mt. anticline and Cacapon Mountain anticlinorium to the east.

Surficial geology presents a diverse picture of alluvium, elevated terraces, alluvial and debris flow fans and minor landslide features. Two significant effects here are first, the extremely thin alluvial deposits along the major rivers, which may be related to late Pleistocene degradation when sea level was significantly low than at present. Secondly, high erosion levels exceeding 600 feet (183m) above the major streams may not be high terraces, but the remnants of planation surfaces dating to Pre-Pleistocene.