Grant Award View - GA64913-V1

The hidden zone at the base of ice sheets includes features such as sediment layers, that may be saturated or not, be frozen or not, and lie over bedrock of variable composition. These features help to control the past and present behaviour of the Antarctic ice sheets and how easily they slide over the rock beneath. We can make better decisions on the future impact of sea level rise if we understand how ice sheets change and whether this will occur gradually or suddenly. At present, predictions of ice sheet behaviour are limited by lack of detailed information on the ice sheet-bedrock interface zone.

We address this information deficit through research that uses naturally occurring background seismic signals, recorded by rapidly deployed posthole instruments. We will use these signals to find sub-ice sediment thickness and character at key locations, and demonstrate a novel method that could have wide uptake by other Antarctic nations that work to understand global change.