Claritas Fossae

Claritas Fossae is a group of troughs in the Phoenicis Lacus and Thaumasia quadrangles of Mars, located at 31.5 S and 104.1 W. The structure is 2,050.0 km long and was named after a classical albedo feature name.

Long narrow depressions on Mars are called fossae. This term is derived from Latin; therefore fossa is singular and fossae is plural. Troughs form when the crust is stretched until it breaks. The stretching can be due to the large weight of a nearby volcano. Fossae/pit craters are common near volcanoes in the Tharsis and Elysium regions. A trough often has two breaks with a middle section moving down, leaving steep cliffs along the sides; such a trough is called a graben.