Abstract This field guide covers a two-day west-to-east transect across the epicentral region of the 2011 M5.8 Mineral, Virginia, earthquake, the largest ever recorded in the Central Virginia seismic zone. The field trip highlights results of recent bedrock and surficial geologic mapping in two adjoining 7.5-min quadrangles, the Ferncliff and the Pendleton, which together encompass the epicenter and most of the 2011–2012 aftershocks. Tectonic history of the region includes early Paleozoic accretion of an island arc (Ordovician Chopawamsic Formation) to Laurentia, intrusion of a granodiorite pluton (Ordovician Ellisville pluton), and formation of a post-Chopawamsic successor basin (Ordovician Quantico Formation), all accompanied by early Paleozoic regional deformation and metamorphism. Local transpressional faulting and retrograde metamorphism occurred in the late Paleozoic, followed by diabase dike intrusion and possible local normal faulting in the early Mesozoic. The overall goal of the bedrock mapping is to determine what existing geologic structures might have been reactivated during the 2011 seismic event, and surficial deposits along the South Anna River are being mapped in order to determine possible neotectonic uplift. In addition to bedrock and surficial studies, we have excavated trenches in an area that contains two late Paleozoic faults and represents the updip projection of the causative fault for the 2011 quake. The trenches reveal faulting that has offset surficial deposits dated as Quaternary in age, as well as numerous other brittle structures that suggest a geologically recent history of neotectonic activity.

Abstract Exposures of the Catskill elastic wedge are located in Pendleton County, West Virginia, and include parts of the Brandywine and Fort Seybert 7½-minute quadrangles (Fig. 1). The left hand topographic map in Figure 1 shows all six stops along U.S. 33; it is an enlarged portion of the 2 degree Charlottesville quadrangle. The right hand map is a part of the 7½-minute Brandywine quadrangle showing location of Stop 5.

Abstract Outcrops of the Taconic elastic sequence and the general geology in the vicinity of the Allegheny Front are exposed at Judy Gap on U.S. 33, Pendleton County; Circleville and Spruce Knob, 7½-minute quadrangles about 8 miles (13 km) westnorthwest of Franklin, West Virginia (Fig. 1). West Virginia 28 and 33 provide access for any kind of vehicle including busses. All other travel in the area will be on dirt roads or narrow paved roads that provide access only by passenger cars and vans.