At the base of Seneca rocks, a thrust fault has pushed the Valley and Ridge province (intensely faulted and folded rocks) over the Appalachian Plateau province (gently folded rocks).   There is a viewing platform near the Seneca Rocks Discovery Center where the Silurian Tuscarora quartzite forms the erosionally resistant front of the steep Seneca Rocks. The quartzites and related Ordovician limestones just behind the quartzites to the southeast form the left limb of the large incised Wills Mountain anticline which runs the length of the Germany Valley.  The viewing platform sits on the more gently folded and flatter sections of the Appalachian Plateau. The mountain building here occurred in the Permian.