Structures of the Appalachian Foreland fold thrust belt: New York City, to Knoxville, Tennessee, June 27 - July 8, 1989

The Appalachian Orogenic Belt, which extends along the eastern coast of North America from Newfoundland to Alabama is a structural geologist's delight. Geologists divide the mountain belt into several geological provinces each having their own unique set of structures and structural problems. Major provinces include the Appalachian Plateau, the Valley and Ridge, the Blue Ridge, and the Piedmont. The focus of this field trip is the Plateau and the Valley and Ridge where sedimentary rocks show the least indication of metamorphism. During mapping of Paleozoic deformation in these two provinces, the 19th century geologists, H.D. and W.B. Rogers, first realized that there was structural regularity along strike to both asymmetric folds and thrust faults. Although the Rogers brothers' initial observations are still valid, detailed mapping during the subsequent 145 years has shown that several subprovinces of the Appalachian foreland have their own characteristic structures. The purpose of field trip T166 is to examine variation in style of foreland deformation along a strike-parallel traverse of 1200 km from eastern New York to eastern Tennessee. The Appalachians are particularly convenient for such a study of structural style because this mountain belt is exhumed, exposing deep structures which are only detected seismically or in well data in younger belts.