NASA Boulders on a Martian Landslide

The striking feature in this image, acquired by the HiRISE camera on NASA's Mars Reconnaissance Orbiter on March 19, 2014, is a boulder-covered landslide along a canyon wall. Landslides occur when steep slopes fail, sending a mass of soil and rock to flow downhill, leaving behind a scarp at the top of the slope. via NASA http://www.nasa.gov/image-feature/boulders-on-a-martian-landslide