Active drumlin found under ice sheet

CAMBRIDGE, England, Jan. 23 (UPI) -- A British-led team of researchers has found a huge drumlin -- a mound of sediment and rock -- actively forming and growing under the Antarctic ice sheet.

The discovery is said to shed new light on ice-sheet behavior and might have implications for predicting how ice sheets contribute to sea-level rise.

Drumlins are well known features of landscape scoured by past ice sheets and are readily visible in Scotland and Northern England where they were formed during the last ice age. Drumlins form underneath the ice as it scrapes up soil and rock, slowing the rate at which the ice can flow.

Scientists from the British Antarctic Survey in Cambridge, Swansea University and the U.S. National Aeronautics and Space Administration's Jet Propulsion Laboratory used a new technique of time-lapse seismic surveying to find the drumlin.

Lead author Andy Smith of BAS said the research marks the first time anyone has observed a drumlin actually forming under the ice.

"These results will help us interpret the way ice sheets behaved in the past, and ... predict how they might change in the future," he said.

The finding is described in the current issue of the journal Geology.