Details

Autor(en) / Beteiligte

• Shen, Weisen
• Wiens, Douglas A.
• Lloyd, Andrew J.
• Nyblade, Andrew A.

Titel

A Geothermal Heat Flux Map of Antarctica Empirically Constrained by Seismic Structure

Ist Teil von

• Geophysical research letters, 2020-07, Vol.47 (14), p.n/a

Ort / Verlag

Washington: John Wiley & Sons, Inc

Erscheinungsjahr

2020

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• The geothermal heat flux (GHF) is an important boundary condition for modeling the movement of the Antarctic ice sheet but is difficult to measure systematically at a continental scale. Earlier GHF maps suffer from low resolution and possibly biased assumptions in tectonism and crustal heat generation, resulting in significant uncertainty. We present a new GHF map for Antarctica constructed by empirically relating the upper mantle structure to known GHF in the continental United States. The new map, compared with previously seismologically determined one, has improved resolution and lower uncertainties. New features in this map include high GHF in the southern Transantarctic Mountains where warmer uppermost mantle is introduced by lithospheric removal and in the Thwaites Glacier region. Additionally, a modest GHF in the central West Antarctic Rift system near the Siple Coast and an absence of large‐scale regions with GHF greater than 90 mW/m2 are found. Plain Language Summary The flow of the heat from Earth's interior into the ice sheet of Antarctica, or geothermal heat flux, has been poorly constrained but is important for understanding the movement of the ice sheet. In this study, we present a new map of the geothermal heat flux estimated from the latest studies of the seismic structure of Antarctica. This is accomplished by directly relating seismic wave speeds with heat flux for the continental United States, a place where many local heat flux measurements have been collected. The new map contains features that have not been reported before. For example, we find that more heat is coming out from the base of the southern Transantarctic Mountains, which is perhaps related to the missing thick and cold lithosphere beneath that region. We also report that part of West Antarctica may have lower geothermal heat flux than previously reported. The new map will help model the movement of the Antarctic ice sheet and predict its future. Key Points A new geothermal heat flux map for the continental Antarctica is presented Based on the latest seismic structure of Antarctica, the new map has improved resolution and reduced uncertainties New features of the map include high GHF in the Thwaites Glacial region and southern Transantarctic Mountains