Numerical model of the geothermal regime on the Beaufort Shelf, arctic Canada since the Last Interglacial

摘要: [1] A finite element geothermal model is developed for the outer Mackenzie Delta-Beaufort Sea shelf to predict permafrost evolution since Last Interglacial ~130–116 kaBP(cal). The purpose reconcile sparse observations of depth and extent ice-bonded with sediment properties paleoenvironment. level curves determine, as a function time, areas that were subaerially exposed, promoting aggradation, submerged, degradation. Assuming starting point paleoclimate similar today persisted through Interglacial, subsequently aggrades in advances seaward from present shoreline shelf/slope bathymetric break by Glacial Maximum (LGM) ~26 Modeled exhibits reduced growth progression correlate early middle Wisconsin stillstands sea level. Following LGM rise level, offshore degrades base rises ~100 m its ~600 m. limit modeled lies at ~95 isobath, within 1 km break. replicates features body observed seismically demonstrates warm outflow River depresses upper surface tens meters 20 m isobath. Although Pleistocene predated Wisconsinan, paleoenvironment last 125,000 years sufficient develop depth, extent, principal body.