View of the Acheron Fossae region on Mars
View of the Acheron Fossae region on Mars
The region around Acheron Fossae is a classic example of a tectonic structure known as a horst and graben system: As a result of the expansion of the crust, large blocks slide along normal fault surfaces into the deformable rock mantle and form graben. The ridges that remain standing between them then form the ‘horsts’. This image shows one of the many filled graben in this region.