Tangled Terrain in Acheron Fossae
More than a thousand kilometers north of the giant volcano Olympus Mons lies a geologically jumbled zone. In Acheron Fossae, part of the volcanic province of Tharsis, dozens of faults curve like shards of window glass. These mark where tensions in the martian crust stretched and broke the surface, and buckled it up and down.
This impact crater, 8.2 km (5.1 miles) wide, shows evidence that the faulting in Acheron continued over many years. The meteorite making the crater struck fault-shattered ground and destroyed all traces of grabens and ridges where it hit.
These bumps lie less than 100 kilometers (62 miles) northeast of Diacria Patera, a broad shield volcano superimposed on part of Acheron Fossae. (Diacria lies outside the image field of view.) The larger bump has a diameter of 5.7 km (3.5 miles) and a height of about 1,300 meters (4,300 feet); the smaller one rises less than 100 meters (330 feet).