ABSTRACT
Geologic structure is interpreted largely by its geomorphic expression and context, taking into account that each planet or moon has a different atmosphere and that none have liquid water at the surface (although some have had in the past). All of the planets have extremes of temperature. An area of horsts and grabens implies extension and normal faulting. Lateral offset of linear ridges indicates strike-slip faulting. Arcuate escarpments suggest thrust faulting, especially if folding is seen and shortening is implied by the local context.
