Paleomagnetism applied to tectonic problems in south-central Alaska and in the central Appalachian Valley and Ridge Province

Paleomagnetic, rock magnetic, finite strain, and rock fabric analyses have been used to investigate the role of the Castle Mountain fault in the accretion history of southern Alaska, the relationship between penetrative strain and synfolding magnetizations in the Mississippian Mauch Chunk Formation, and the effects of grain-scale strains on the Silurian Bloomsburg Formation paleomagnetic pole.;Paleomagnetic and rock magnetic analyses from the Arkose Ridge and Chickaloon formations in southern Alaska indicate that these rocks contain a pre-folding magnetization which yields a paleomagnetic pole for the Chickaloon Formation at 50.5;Paleomagnetic results from Mauch Chunk Formation sites on both limbs of the Frackville Anticline reveals a two polarity characteristic magnetization that appears synfolding at 75% unfolding (I = 27.3;The relationship between the strain geometry and remanence around three central Appalachian Valley and Ridge folds indicates that penetrative deformation has also rotated the characteristic magnetization in the Bloomsburg formation from a prefolding, Silurian magnetization to an apparent synfolding, Devonian configuration. Based on the low-strained sites from this study, a new Bloomsburg Formation paleomagnetic pole is calculated at 18.5...