The Moulton "horizontal ice core" trench. Photo by Nelia Dunbar (New Mexico Tech).

Ice Cores: Mt Moulton

500,000 years of West Antarctic volcanic and climate history laid bare in exposed tephra layers and blue ice.

SIL Measurements

H: liquid water & ice
O: liquid water & ice

 

Why Study?

Antarctic ice cores older than 100 ka are mostly limited to East Antarctica. At present we have no way of deducing how the West Antarctic ice sheet (WAIS) responded to the previous interglacial climate (between 120 and 130 ka). Such information will help improve predictions of the response of the WAIS to future climate change.

The summit of Mt. Moulton, West Antarctica, contains a 600-m thick horizontally exposed section of ice with intercalated tephra layers, sourced from nearby Mount Berlin. Dating of the tephra layers provides an unprecedented chronology of climate change in WAIS between 14,500 and 492,000 years ago. Initial analyses suggest that the Moulton site may offer an unparalleled repository of ancient West Antarctic snow and trapped air that can be used to investigate West Antarctic climate over as the last 500 k years. (from ICDS web site, Univ. Wisconsin-Madison).

Participants

The 03/04 field party at Mt. Moulton. From left to right: Trevor Popp, Pratigya Polllisar, Todd Sowers, Bill McIintosh, and Nelia Dunbar. The Eclipse drill is set up on the blue ice field with the trench cut out of ice. Mt. Berlin in the background lies ~30km from Moulton and is the source of the tephra found at the Moulton site. An outcropping of a thick tephra layer runs behind the party and drill. (from ICDS web site, Univ. Wisconsin-Madison).

  • N. Dunbar (PI), New Mexico Institute of Mining and Technology
  • W.C. McIntosh (co-PI), New Mexico Institute of Mining and Technolog
  • T. Sowers (co-PI), Penn State University
  • Jim White (co-PI), INSTAAR, University of Colorado
  • Trevor Popp, Ph.D. Candidate, INSTAAR, University of Colorado

SIL Role

Trevor Popp participated in the field, providing drilling expertise. Togther, the team set up the Eclipse drill in five separate locations, and drilled over 203m of firn and 73m of Blue ice. The stable isotope analyses were performed at INSTAAR, SIL.

Location

Map of Antarctica.

Mt. Molton is located near the coast in West Antartica,reached by Twin Otter from McMurdo.

Funding

  • US National Science Foundation

Other

 
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