Perspective view of the transition zone between Margaritifer Terra and Aurorae Chaos
At the transition between the Margaritifer Terra highland region and the Aurorae Chaos depression, the plain of the southern highlands is heavily furrowed and characterised by grabens, valleys, hollows and shattered landscape. The crust was torn apart by tensile tectonic forces, while underground ice was probably stored in cavities directly beneath the surface. This thawed due to a heat source – rising magma from a volcano or the heat generated by a nearby asteroid impact – and rose to the surface before flowing north. The resulting cavities collapsed, leaving a landscape that is described as ‘chaotic terrain’ by planetary geologists.