Named the Stickley Run Member of the Martinsburg Formation in the Shenandoah Valley of northern VA and the eastern panhandle of WV for Stickley Run near Strasburg, Shenandoah Co., VA. This new member includes all rocks above the highest knobbly-weathering limestone of the Edinburg Formation up to and including all platy limestones that are interbedded with shale and graywacke of the Martinsburg; this includes rocks previously assigned to the Oranda Formation (abandoned herein). Consists of dark-gray, laminated to thin-bedded shaly limestone and calcareous shale. Thickness is 610 to 900 feet. Member is recognized on both limbs of the Massanutten synclinorium and thins to 350 feet at the south end of the synclinorium. Overlies the Edinburg Formation and underlies shale, siltstone, and graywacke of the Martinsburg Formation. The lower contact is placed at the base of the lowest calcareous shale or shaly limestone that overlies thicker-bedded, cobbly limestone of the Edinburg; upper contact placed at top of uppermost platy limestone underlying noncalcareous shales and graywacke of the Martinsburg. The Stickley Run is of Middle Ordovician age based on conodonts.

Source: GNU records (USGS DDS-6; Reston GNULEX).