A system of steeply inclined fractures (dipping between 45° and 79° inclusive) occurs within and near the outcrop belt of Upper Silurian evaporite beds along the northern edge of the Appalachian Plateau in central and western New York. This system is superimposed upon a system of regional orthogonal fractures in lower Paleozoic sedimentary strata in the same area. Associated with the steeply inclined fractures are numerous folds inferred to be related to solution in underlying evaporite beds. The purpose of this study is to describe and define the distribution of the steeply inclined fractures and to interpret their dynamic significance.
Prior to this study the steeply inclined fractures received only superficial attention. DeGroff (1954, p. 43-50), without being more specific, considered them to be manifestation of local rather than regional causes. Furbush (1952, p. 83), Phillips (1955, p. 14), and Tolley (1957) either suggested of implied that the steeply inclined fractures are genetically related to thrust faults. Leutze (1955, p. 14) believed the fractures to be directly related to subsidence, but he did not suggest the dynamic relationship.