INSET: USGS IMAP 2402: Geologic map of the MTM-15147 quadrangle, Mangala Valles region of Mars

The map area is in the Mangala-Memnonia region (fig. 1), which contains remarkably diverse geologic features and terrain types. Studies of the Mariner 9 images revealed the wide range of ages of the major rock units in this region; age assignments were based on the density of impact craters preserved on the various surfaces (Mutch and others, 1976, p. 56-60; Scott and Carr, 1978; Mutch...