Drill Rig on Greenland Ice Sheet (IMAGE) University of Utah Caption This drill rig was used to extract firn cores from within the Greenland firn aquifer. One of the snowmobiles used in the 186 mile traverse of the ice sheet to reach the drill site. Clément Miège, University of Utah Ph.D. student and Terry Gacke, Ice Drilling Design and Operations. Credit Evan Burgess, co-author Usage Restrictions None 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.