This image shows coarse-grained layers from around the edge of a low plateau called "Home Plate" inside Mars' Gusev Crater. One possible origin is material falling to the ground after being thrown aloft by an explosion such as a volcanic eruption or meteorite impact.
The panoramic camera (Pancam) on NASA's Mars Exploration Rover Spirit acquired the exposures for this image on Spirit's 749th Martian day (Feb. 10, 2006). This view is an approximately true-color rendering mathematically generated from separate images taken through all of the left Pancam's 432-nanometer to 753-nanometer filters.