Short Hill Mountain - Geology

Geology

The rocks underlying Short Hill are of the late Proterozoic and early Paleozoic eras. The formation consists primarily of metabasalt greenstone deposited during the early Catoctin Formation and interspersed with metasedimentary phyllite, schist and breccia, which were deposited later. The rocks were originally deposited contiguous with those of the Blue Ridge Mountains and uplifted together during the Grenville Orogeny. The two ridges were later separated in the late Paleozoic era by movement along the Short Hill Fault, which runs along the western edge of the mountain. During the Alleghenian Orogeny the rocks were pushed westward to their present location and uplifted once more.