Chukchi Borderland Composite Tectono-Sedimentary Element, Arctic Ocean

The Chukchi Borderland (ChB) is a prominent bathymetric structure located between the deep-water Chukchi Abyssal Plan and the Canada Basin in the Arctic Ocean. This region represents a block of extended continental crust that was tectonically connected to both Siberia and North America before the formation of the Canada Basin. The interior of the ChB is dissected by normal faults into high-standing blocks and troughs that define the first-order structural elements of the Chukchi Plateau, the Northwind Basin and the Northwind Ridge. The post-Hauterivian (Brookian) strata thin from 16 km in the North Chukchi Basin (south of the ChB) to 4–5 km in the Northwind Basin. The basin fill records a history of alternating periods of tectonic extension and quiescence, as reflected in distinct depositional cycles. In this chapter, we describe the ChB as a composite tectono-sedimentary element (CTSE) using original and published 2D multi-channel seismic reflection profiles, tied to the well-calibrated stratigraphy of the Chukchi Shelf and integrated with potential data. We also provide a brief summary of potential hydrocarbon plays based on analogies with the Arctic Alaska Basin.