Tikoff (IMAGE) University of Wisconsin-Madison Caption Basil Tikoff places a delicate gravity meter on bedrock on the east side of Laguna del Maule. Gravitational force is reduced when more hot, low-density magma gathers belowground. Tikoff, a UW-Madison professor of geoscience, is an author on the Science Advances paper. Credit David Tenenbaum, 2013 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.