Magma Formation (image) Rice University Caption A microscopic sample of rock squeezed in a lab at Rice University to pressures it would experience hundreds of kilometers inside the Earth's mantle show evidence of magma (silicate melt) formation. New research led by Rice shows magma can form as deep as 250 kilometers inside the mantle. Credit Dasgupta Group/Rice University Usage Restrictions None 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.