Polygonal Fracturing of the South Polar Layered Deposits
Polygonal Fracturing of the South Polar Layered Deposits
PSP_004959_0865  Science Theme: Polar Geology
This image shows the south polar layered deposits, with curving layer outcrops caused by erosion of valleys into the deposits.

On closer inspection, polygonal (mostly rectangular) fractures are visible, mostly near the center of the image. Polygonal fractures are also observed in the north polar layered deposits, but typically on a much smaller scale.

Here in the south, the fractures cross layer boundaries, while in the north the fractures are usually confined to a single layer. Therefore, the fractures in the south polar layered deposits formed after the surface was eroded to the configuration seen here, probably due to expansion and contraction of water ice below the surface.

Written by: Ken Herkenhoff  (19 September 2007)
Acquisition date
17 August 2007

Local Mars time

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