Hemispheres Apart: The Crustal Dichotomy on Mars

  title={Hemispheres Apart: The Crustal Dichotomy on Mars},
  author={Thomas R. Watters and Patrick J. McGovern and Rossman P. Irwin},
  journal={Annual Review of Earth and Planetary Sciences},
The hemispheric dichotomy is a fundamental feature of Mars, expressed by a physiographic and geologic divide between the heavily cratered southern highlands and the relatively smooth plains of the northern lowlands. The origin of the dichotomy, which may have set the course for most of the subsequent geologic evolution of Mars, remains unclear. Internally driven models for the dichotomy form the lowlands by mantle convection, plate tectonics, or early mantle overturn. Externally driven models… 

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