Neoproterozoic-Cambrian detrital zircon provenance record of the Canadian high Arctic and its significance to circum-Arctic paleogeography

The rotational opening scenario for the Amerasian Basin of the Arctic Ocean implies that pre-Mesozoic sedimentary sequences underlying the Canadian high Arctic and Arctic Alaska-Chukotka microplate should have been deposited contiguously. In this study we use detrital zircon U-Pb geochronology to decipher the Neoproterozoic-Cambrian provenance record of the Franklinian basin, Canadian high Arctic, and constrain the duration of these stratigraphic connections. The results provide a new detrital zircon reference frame for the Canadian high Arctic and show that Franklinian basin strata were derived from Mesoproterozoic, late Paleoproterozoic, and Neoarchean crystalline rocks of the Laurentian craton. This reference frame differs substantially from the detrital zircon signatures of Neoproterozoic-early Paleozoic strata in the Eurasian high Arctic, Siberia, and Seward Peninsula and Brooks Range regions of Arctic Alaska. Putative stratigraphic connections with Alaskan North Slope successions are doubtful in light of their 760-890 Ma detrital zircons and fossils of Siberian affinity. The Alaskan North Slope is therefore most likely an exotic crustal block that accreted to the Canadian Arctic margin in mid-Paleozoic time. Existing stratigraphic data that are used to support the rotational opening scenario must be restricted to those for late Paleozoic-Mesozoic rocks in the Sverdrup Basin in Arctic Canada and Hanna Trough in Arctic Alaska.