This observation shows a sinuous ridge that may be an inverted stream. Streams can be inverted (become ridges) if they are made of stronger material than their surroundings.

Another way to make high-standing channels is to have water and sediment flow through a channel in the ice at the bottom of a glacier. After the glacier is gone, the sediment can be left behind, forming a ridge called an esker.

This caption in based on the original science rationale.

Written by: HiRISE Science Team (audio by Tre Gibbs)   (20 March 2013)

More info and image formats at http://hirise.lpl.arizona.edu/ESP_024224_2190

Image: NASA/JPL/University of Arizona