Unusual Faulting (IMAGE) Columbia Climate School Caption Japan's risk of giant tsunamis may have grown when the angle of a down-going slab of ocean crust declined. Top: ocean crust (right) slides under continental crust at a steep angle, causing faulting (red lines) in seafloor sediments piled up behind. Bottom: as the angle shallows, stress is transferred to sediments piled onto the continental crust, and faults develop there. Blue dots indicate resulting earthquakes. At left in both images, the change in angle also shifts the region where magma fueling volcanoes is generated, pushing eruptions further inland. Credit Adapted from Oryan and Buck, <em>Nature Geoscience</em> 2020 Usage Restrictions Credit must be given. 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.