In astrogeology, chaos terrain (or chaotic terrain) is a planetary surface area where features such as ridges, cracks, and plains appear jumbled and enmeshed with one another. Chaos terrain is a notable feature of the planets Mars and Mercury, Jupiter's moon Europa, and the dwarf planet Pluto. In scientific nomenclature, "chaos" is used as a component of proper nouns (e.g., "Aureum Chaos" on Mars).
Tography map of Oxia Palus region of Mars showing the location of a number of chaos regions
Map of Margaritifer Sinus quadrangle with major features labeled. Aureum Chaos is near the top of the map.
Huge canyons in Aureum Chaos, as seen by THEMIS. Gullies are rare at this latitude. Image from Margaritifer Sinus quadrangle.
Iani Chaos, as seen by THEMIS. Sand from eroding mesas is covering brighter floor material. Click on image to see relationship of Iani Chaos to other local features. Image from Margaritifer Sinus quadrangle.
Quadrangle map of Oxia Palus quadrangle labeled with major features. This quadrangle contains many collapsed areas of Chaos and many outflow channels (old river valleys).
Erosion in Aram Chaos, as seen by THEMIS. Image in Oxia Palus quadrangle.
Blocks in Aram showing possible source of water, as seen by THEMIS. Image in Oxia Palus quadrangle.
Hydraotes Chaos, as seen by HiRISE. Click on image to see channels and layers. Scale bar is 1000 meters long. Image in Oxia Palus quadrangle.
Hydaspis Chaos, as seen by HiRISE. Image in Oxia Palus quadrangle.