West Antarctic Ice Sheet Ice Core Sample (image) Santa Fe Institute Share Print E-Mail Caption This is a section of the West Antarctic Ice Sheet ice core sample with a dark ash layer. Credit Image courtesy Heidi Roop. Usage Restrictions None Share Print E-Mail 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.