Appalachian Grenville massifs: pre-Appalachian translational tectonics

Abstract

Precambrian massifs and terranes of the eastern USA are in the present day separated by three major tectonic boundaries. The westernmost external massifs lie along the east side of the "Paleozoic Basement Tectonic Front' and originated inboard of the late Proterozoic margin of the Ancestral North American Craton (ANAC). Restoration of the "Paleozoic Basement Tectonic Front' eastward to coincide with the prominent gravity gradient (which marks the Paleozoic margin of the ANAC) allows examination of the ANAC during the late and middle Proterozoic. -from Authors