Geoprobe Core Tube (IMAGE) Dickinson College Caption A core tube containing saprolite from the subsurface at the Sierra Nevada study site. Cores were obtained using a Geoprobe push-core system. Credit P. Hartsough 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.