|Title:||High Heat-Flow Beneath the Central Portion of the West Antarctic Ice Sheet|
|Author:||Clow, G.D., Cuffey, K.M. and Waddington, E.D.|
|Periodical:||American Geophysical Union, Fall Meeting 2012, abstract #C31A-0577|
Based on the tectonic setting and slow seismic velocities in the upper mantle, the geothermal heat flow beneath the West Antarctic Ice Sheet is expected to be both relatively high and spatially variable. Unfortunately, very few heat flow measurements have been made in West Antarctica to confirm or refute this expectation. During December 2011, high-precision temperature measurements were made in the 3405-m deep borehole recently completed at the WAIS Divide ice core site (79° 28.059'S, 112° 05.137'W) in the central portion of the West Antarctic Ice Sheet. Interpretation of the temperature measurements indicates the ice sheet is melted at the bed at this location and that the basal melting rate is extraordinarily high, 1.5~cm a-1 (the borehole does not penetrate all the way to the bed to protect the underlying environment). The associated geothermal heat flux is estimated to be about 240 mW m-2, 4-5 times the continental average. Given the absence of a surface depression at the WAIS Divide site, this high heat flow is likely to be the regional value (horizontal scale ≥ 30~km), rather than simply a local anomaly.