Finding Weaknesses in the Earth's Crust (IMAGE) University of Adelaide Caption This is a map of viscosity of the crust and upper mantle produced by our modeling. Warm colors are low viscosity (weak) and cool colors are high viscosity (strong). Credit Credit Jiashun Hu, University of Illinois Usage Restrictions For use with this story only 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.