Posted by tourdemars to Mars Express at October 5, 2004 10:46 PM

These images, taken by the High Resolution Stereo Camera (HRSC) on board ESA’s Mars Express spacecraft, show the Claritas Fossae tectonic grabens and part of the Solis Planum plains. The Claritas Fossae (‘fossa’ is Latin for trough) region is characterised by systems of ‘grabens’ running mainly north-west to south-east. These can be traced several hundred kilometres up to the northern Tharsis shield volcanoes. A graben forms when a block of the planet’s crust drops down between two faults, due to extension, or pulling, of the crust.