This enhanced-color image shows a small portion of a dark crater floor in the Tyrrhena Terra region of Mars. This is largely ancient hard bedrock that has been cratered by numerous impacts over the eons.
Two other interesting geological features in Tyrrhena Terra (not pictured here): Herschel Crater and Tyrrhena Patera, one of the oldest volcanoes on Mars.
Written by: Alfred McEwen (2 February 2017)
More info and image formats at http://hirise.lpl.arizona.edu/ESP_021716_1685
Image: NASA/JPL/University of Arizona