Tharsis Volcanics

This VIS image shows part of the Tharsis lava plains between Sulci Gordii and Ulysses Fossae. While large volcanoes and huge lava flow sheets dominate the Tharsis region, extensive tectonic features are also present. The entire Tharsis region forms a bulge on the equatorial part of Mars, generated by the uplift of magma rising through the crust. The motion of subsurface magma created extensional forces, tearing the surface apart releasing the magma in floods of lava and volcano building events. At the same time the extension cracked the surface creating the faults and graben also seen in the region. In this image, the linear graben post-date the lava flows.