Crumpling lava

The butterfly crater may draw the eye, but it’s far from the only feature of interest here. The rest of the frame is largely flat, lending the spotlight to a cluster of steep, flat-topped rocky outcrops – known as mesas – to the left (shown in the zoom in perspective view below). The higher patches of ground here have been slowly worn away, with the remaining hills being those that have managed to resist erosion over time.

The mesas stand out clearly against the tan-coloured surroundings due to the layers of dark material that have been exposed along their edges. As on Earth, this material is probably rich in magnesium and iron, and created by volcanism. This region likely saw quite a bit of volcanism in the past, with lava and ash deposits building up over time and being buried by other material through the years.

Signs of lava can be seen here in ‘wrinkle ridges’: folded patterns that likely formed here when lava flowed, cooled, and contracted, causing the surface to crumple.