Antarctic Sea Floor Sediment Sampling (IMAGE) Boston College Caption This is a schematic of the drilling rig used to collect the sediment core analyzed by Shakun and colleagues from beneath the Ross Ice Shelf. The drill penetrated 280 feet of ice, 2800 feet of ocean water, and 4200 feet of sediment, recovering a geological history of the Antarctic Ice Sheet stretching back millions of years. Credit Angie Fox, ANDRILL Usage Restrictions Must use credit with image reproduction. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.