South Polar Layered Deposits

Similar to ice cores taken from Greenland and Antarctica, Mars also has fine-scale layered deposits in both the north and south polar regions. In this image from the south pole, alternating light and dark bands represent varying amounts of dust or sand mixed in with carbon dioxide ice. These layers are related in part to climate cycles caused by variations in the tilt of Mars' rotational axis, as well as other orbital variations that occur on geologic time scales (tens of thousands of years).