Rethinking “Yellowstone in Yukon” and Baja British Columbia: Paleomagnetism of the Late Cretaceous Swede Dome stock, northern Canadian Cordillera

摘要: [1] Paleomagnetic results obtained from the 69.8 Ma Swede Dome stock, emplaced into pericratonic Yukon Tanana Terrane (YTT) west of Dawson, Yukon, indicate a minimal northward translation 360 ± 575 km and clockwise rotation 20° 23° with respect to North America, in accord displacement 425 along nearby Tintina Fault. Coeval Carmacks Group volcanics contrast have previously indicated ∼1900 been proposed be displaced manifestation fixed Yellowstone hot spot, thus providing an independent estimate Late Cretaceous paleoposition “Baja British Columbia” terranes western America. A compilation recent mid paleomagnetic YTT Intermontane Belt (IMB) reveals that result is anomalous. The IMB terranes, which form bulk Baja Columbia, appear instead experienced <1000 America since 70 Ma, consistent geological estimates motion plausible accommodating faults. In addition, past mobility Hawaii-Emperor spot implies Pacific spots may ∼1200 southward 81 47 Ma. If so, then if it existed at would likely produced magmatism ∼1000 north Yellowstone's current latitude, “moderate” (<1000 km) post-70 their present position