Fission-track dating of the tectonic development of the San Juan Islands, Washington

摘要: The San Juan Islands of Washington State form a geologically complex province located between the north Cascades, Vancouver Island, and Olympic Peninsula. We have obtained 53 fission-track dates from that help constrain its late Paleozoic to early Cenozoic tectonic sedimentary history relationship neighboring geologic terranes. can be divided into two main blocks separated by Haro fault. South fault, complexly deformed, metamorphosed, probably exotic Late Cretaceous rocks four imbricate thrust plates south- east-dipping Early faults. Reset zircon indicate thrusting may produced an upside-down geothermal gradient in uppermost plate, Decatur terrane. If present, this was conductive or frictional heating associated with now-eroded overlying fault hot plate....