Million-Year-Old Ice Cored from Buried Ice Mass in Ong Valley, Transantarctic Mountains, Antarctica.

We cored a massive buried ice body in Ong Valley, Transantarctic Mountains, Antarctica. We retrieved two ice cores of approximately 10-meters long. The ice mass is buried under a thin layer (< 1 m) of glacial till which has been deposited by sublimation of the ice. It has previously been proven that the age of the above laying sublimation till is > 1.1 Ma and therefore making this one of the oldest ice on Earth

The two ice cores contain meter long sections of both clear ice, including air bubbles and ice lenses, and dirty ice; containing suspended matter ranging from cobbles to very fine-grained sediment. Parts of the dirty ice sections show distorted layering as well as sections of highly concentrated ice cemented sediment. The drill sites of the two ice cores are located approximately 300 meters apart and display some similarities of sedimentary features at correlated depths.

This study attempts to answer the question of whether or not ancient ice can be preserved under a thin layer of glacial debris by determining the age of the ice as well as its sublimation rate. Measuring the concentrations of cosmogenic nuclides ¹⁰Be, ²⁶Al and ²¹Ne within the overlaying debris and mineral matter suspended in the buried ice, allows for the age and sublimation rate to be uniquely determined. Cosmogenic nuclides are rare isotopes produced in mineral matter when exposed to high energy cosmic rays near or at Earth's surface. The concentration of cosmogenic isotopes found in surficial materials can be related to the length of time the material has been exposed at the surface. When encountering Earth's surface, cosmic ray particles impact target minerals such as quartz in rocks resulting in production of cosmogenic nuclide isotopes 10Be, 26Al and 21Ne. If indeed the buried ice is found to be old and sublimating slowly it can potentially yield direct information on climate history of the vast interior of Antarctica, past atmospheric chemistry, ancient life forms, and geology of greater antiquity than most currently know ice bodies.