Polygonal patterned ground

Places on Mars that display polygonal ground may indicate where future colonists can find water ice.

Low center polygons have been proposed as a marker for ground ice.

It is formed by repeatedly annealing the crack pattern, as the same ground is partially melted every summer, then frozen every winter, until thousands of years later, it settles into a thermodynamically favored state, which is dominated by Y-junctions.

The troughs along the edges of high center polygons may become filled with sediment.

For, as yet unknown reasons, boulders are often arranged in various shapes that include polygons.

A study around Lomonosov Crater found that they were not caused by fracture networks.

[29][30] Much of the Martian surface is covered with a thick ice-rich, mantle layer that has fallen from the sky a number of times in the past.

The mantle layer lasts for a very long time before all the ice is gone because a protective lag deposit forms on the top.

After a certain amount of ice disappears from sublimation the dust stays on the top, forming the lag deposit.

Brain terrain lies under polygonal ground when the two are both visible in a region.

[45][46] Many steep surfaces in latitude bands near 40 degrees North and South contain gullies.