Directory

Start date:
Mid November
End date:
Early January
Locations:
Olympus Range, Pivot Peak
Principle Investigator:
Dr Adam Lewis
Organisation:
North Dakota State University
Field season overview:
A four-person field team will deploy to the western Olympus Range in mid-November, with a fifth person added in early December. The camp site rests at the mouth of a north-facing valley just to the west on Bull Pass. The research team will work near their campsite, using a jackhammer to excavate pits into frozen soils. Helicopter flights will be used to make several day trips in the range to map and sample moraines on south-facing slopes. Additionally, researchers plan one research trip to Beacon Valley and one to Pivot Peak.
The western Olympus Range is an east-west oriented mountain chain in the west-central Dry Valleys, dividing upper Wright Valley and McKelvey Valley. Our previous work in the range focused on well-preserved sequences of tills and fossil-rich proglacial lake sediments, which together register a marked climatic cooling in the region 14 million years ago. After this climate cooling, the absence of melt water greatly slowed rates of erosion and deposition in the western Olympus Range, leaving most landscape surfaces preserved over million-year timescales. However, on north-facing slopes in the range, a few small debris-flow channels and alluvial fans rest just below snowbanks and niche glaciers. Their presence indicates that surface melting of ice and snow does take place periodically at high elevation. Researchers plan to date individual beds in these small-scale sedimentary archives as a proxy for melt water production under warmer-than-present climate conditions. They will also use optically stimulated luminescence dating of sandy beds and exposure-age dating of gravels and buried surface clasts to build a chronology. Finally, the researchers will tie their results to other climate records and to climate models in an effort to understand what brings about these periods of climatic warmth.