Repeated Erosion and Deposition in the SPLD (MULTISPECTRUM; credits: Lunexit)

This image of the SPLD shows evidence of multiple episodes of deposition and erosion near their base.

The SPLD, like the North Polar Layered Deposits (NPLD), are thought to contain a record of global climate changes on Mars. The surface of the outcrop shown here slopes generally toward the right. The layering is cut off by deposits that partly fill two broad valleys that were previously cut into the SPLD, probably by wind erosion. These more recent deposits appear to cover the flatter, upper part of the SPLD, and have also been eroded to expose layering with them.