In the HRSC images, multiple grabens of varying depths cut across the right (northern) side of the scene (see annotated image). A closer look reveals smooth material with a streamlined pattern on the floors of these grabens. These features are known as lineated valley fills and typically form through the slow, viscous flow of ice-rich debris (see annotated image). The deposits are believed to be mostly made up of ice covered by a layer of rock – similar to rock glaciers found here on Earth.

The flow-like feature is common in periglacial environments – not only on Earth but also on Mars. Their presence suggests that the region experienced alternating cold and warm periods, driven by repeated freeze–thaw cycles. These climatic fluctuations are caused by changes in Mars’ orbital parameters – especially the tilt of its rotation axis, known as obliquity. Unlike Earth’s relatively stable tilt of about 23.5°, thanks to our loyal companion the Moon, Mars’ axial tilt varies more dramatically and frequently due to gravitational influences from other planets. These obliquity cycles cause periodic shifts in Mars’ climate – and with them, changes in the distribution of ice. Simply put: during periods of high obliquity, ice spreads from the poles toward the mid-latitudes. When the tilt is lower, as it is today, the ice retreats back to the poles, leaving behind visible traces in the landscape.