Planetary Tectonics and Volcanism: The Inner Solar System

Although Earth is the only planet in the solar system with active plate tectonics, the planetary bodies of the inner solar system (Mercury, Venus, the Moon, and Mars) display a familiar array of tectonic and volcanic features. Nonexplosive eruptions of basaltic lava are the most common volcanic activity on Earth and appear to have been the dominant volcanic behavior throughout the inner solar system. Mare-type wrinkle ridges (thrust faults with draping folds) are rare on Earth but are commonly observed on the terrestrial planets. Distributed extensional features are abundant on Mars and Venus; extension tends to be more localized on Mercury and the Moon.