Department of Earth Sciences
Supporting Stations: McMurdo Station
Research Locations: Asgard Range / Beacon and Kennar Valleys
Buried glaciers of the McMurdo Dry Valleys, Antarctica (MDV) represent a potentially far-reaching archive of ancient atmosphere. Unlike relatively fast-flowing ice sheets that continually move toward margins, stagnant and/or slow-moving debris-covered glaciers may contain ice several million years in age; by way of comparison, the oldest ice yet cored from the East Antarctic Ice Sheet is about one million years old. However, even with their documented potential to register long-term climate change, and to serve as proxies for very ancient buried ice deposits on Mars, there has been surprisingly little quantification of the geologic and geomorphologic processes that both preserve and modify debris-covered glaciers in Antarctica. Unknown are important details of ice burial, ice ablation, and the evolution of textural facies within sublimation tills that play critical roles in maintaining and/or modifying buried-glacier ice. Overcoming these deficiencies are primary goals of this proposal. Researchers will develop a suite of quantitative models that elucidate landscape evolution above buried glacier ice, specifically above the Mullins Glacier, and nearby glaciers in the Quatermain Mountains and Asgard Range. The three central objectives are (1) Document the thickness and spatial trends in englacial debris within buried glaciers using Ground Penetrating Radar (GPR).; (2) Document variation in microclimate and its impact on sublimation till development.; and (3) Develop quantitative surface-process models for landscape evolution above buried ice.
Field Season Overview:
The first phase of the fieldwork includes GPR experiments on buried glaciers in the Quartermain Mountains (Beacon Valley, Mullins Valley, Kennar Valley) and Asgard Range (Koenig Valley and Sessruminir Valley). This is only possible during the months of November and December, when colder atmospheric temperatures prevent surface snowmelt. In January, the field party will conduct soil-moisture and melting measurements in the Quartemain Mountains, the Asgard Range and, later in the season, on buried-ice deposits in lower Taylor Valley, Brown Peninsula, Black Island, and coastal regions of Mount Discovery. A reduced team of two will continue studies in the field until the end of January. Throughout the field season from the Beacon Valley base camp, reconnaissance day-trips will be conducted to nearby locations.
Deploying Team Members:
David Marchant (PI)