Flexural Response to Erosional Unloading of Continental Margins: An Example From the Bering Sea, USA

Abstract

The geodynamic response of continental margins to erosion may reveal current and past changes in the location of the continental slope. We model the three-dimensional isostatic response to erosion along the retreating Beringian Margin to test the hypothesis that the margin and its canyons were dominantly eroded during the Pleistocene. Our results predict 900 m of flexural uplift, though evidence for this magnitude of uplift is not observed in Pleistocene and younger deposits, suggesting a substantial amount of margin erosion occurred pre-Pleistocene. Uplift of this magnitude may be represented by a Late Miocene unconformity across the Bering Shelf and upwarped subsurface units at the base of the Beringian Margin. The distribution of uplift from varying canyon incision and margin retreat scenarios has implications for the extent of geodynamic response during erosional periods.