Herðubreið (IMAGE) Purdue University Caption Researchers expect the volcanoes in Mars' Sisyphi Planum region to look similar to subglacial volcanoes on earth, such as Herðubreið in Iceland. Credit Purdue University photo/Sheridan Ackiss 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.