ARCUS | Arctic Research Consortium of the United States

7th Annual ARCUS Award for Arctic Research Excellence


Submitted by   Kristoffer Walker
Authors   Kristoffer Walker, S. McGeary, and S. L. Klemperer
Category   Physical Science
Title   Evolution of the Bristol Bay Basin, Southeast Bering Sea: Constraints from Seismic Reflection and Potential Field Data
Affiliation   Geophysics, Stanford University, Stanford, CA, USA

Abstract

This paper could be classified as a contribution to crustal geophysics, basin evolution, or tectonophysics. We interpret the evolution of the Bristol Bay basin based on a deep seismic reflection profile, lithologic data from a well, unreversed seismic refraction profiles, a bathymetry profile, a magnetics profile, forward modeling of a gravity profile, and flexural modeling of a basin-wide paleosurface. We present evidence that: (1) an early-to-middle Eocene phase of extension initiated fault-controlled subsidence; (2) a late Eocene to middle Miocene phase of volcanic-arc loading led to flexural subsidence, which was amplified by additional factors; and (3) a late Miocene to Holocene resurgence of arc volcanism and a northward prograding delta continued (or possibly increased) flexural subsidence in the backarc region. These observations suggest that the basin's evolution is unusual and has components typically found in both backarc (extension) and retroarc foreland (flexure) basins.