Large areas of plains in the 40 to 50 N latitude belt have a fracture pattern similar to that shown here. The pattern resembles those that form on some lava lakes as a result of cooling. It also resembled patterned ground formed by ice-wedging in the periglacial regions. The polygons on Mars are, however, approximately 100 times the size of suggested terrestrial analogs, and their origin is unknown. The image is about 85 km across.
North is to the upper right.