Basal Exposure of South Polar Layered Deposits

This image shows layering at the base of the south polar layered deposits exposed on a scarp. The south polar layered deposits are composed primarily of water ice with a small amount of dust.

The layers were laid down over a large area near the south pole, probably over the past few million years. They are believed to record recent global climate changes on Mars in much the same way that polar ice in Greenland and Antarctica provide information about varying climatic conditions on Earth.

Some of the layers have an irregular or wavy appearance. This may have been caused by the flow or deformation of the ice at some point in the past, in addition to uneven erosion. A few layers also appear to be converging or to be truncated (center of image). These are called unconformities. Unconformities form when an episode of erosion removes all or parts of existing layers and is later followed by more deposition. Surface fractures, channels, knobs and other features, along with the obscuration of layer contacts, point to a comicated recent history, but also make it difficult to characterize indiviual layers.Written by: Maria Banks   (31 October 2007)

This is a stereo pair with PSP_005089_1040 .

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Image: NASA/JPL/University of Arizona