A multi-ringed basin (also a multi-ring impact basin) is not a simple bowl-shaped crater, or a peak ring crater, but one containing multiple concentric topographic rings; a multi-ringed basin could be described as a massive impact crater, surrounded by circular

chains of mountains A mountain chain is a row of high mountain summits, a linear sequence of interconnected or related mountains,Whittow, John (1984). ''Dictionary of Physical Geography''. London: Penguin, p 87. . or a contiguous ridge of mountains within a larger m ...

resembling rings on a

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. A multi-ringed basin may have an area of many thousands of square kilometres. An impact crater of diameter bigger than about is referred to as a ''basin''. __TOC__ Mare Orientale (Lunar Orbiter 4)

The structure of multi-ring basins

In adjacent rings, the ratio of the diameters approximates :1 ≈ 1.41 to 1.''Moons & Planets'', William K. Hartmann, 2005, p.255ff

Formation

To start, a peak ring crater has * one peak-ring, i.e., a crater rim, which is generally circular, ''and'' * a mountainous region which surrounds the basin center. A multi-ringed basin has an important difference, which is multiple peak-rings. In extremely large collisions, following the impact the rebound of the surface can obliterate any trace of the initial impact point. Usually a peak ring crater has a high structure with a terrace, and has

slump structures A slump is a form of mass wasting that occurs when a coherent mass of loosely consolidated materials or a rock layer moves a short distance down a slope. Movement is characterized by sliding along a concave-upward or planar surface. Causes of slu ...

inside of it. In 2016, research brought forward new theories about the lunar mare called Mare Orientale on Earth's Moon, as to how it formed. Multi-ring basins are some of the largest, oldest, rarest and least understood of impact craters. There are various theories to explain the formation of multi-ringed basis, however there is currently no consensus.

Examples

* In Mexico Chicxulub crater has a sufficient area to have been a multi-ringed basin, * On the largest

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, Ganymede,

Anubis Crater Anubis (; grc, Ἄνουβις), also known as Inpu, Inpw, Jnpw, or Anpu in Ancient Egyptian () is the god of death, mummification, embalming, the afterlife, cemeteries, tombs, and the Underworld, in ancient Egyptian religion, usually depict ...

is a multi-ringed basin, * On the

moon of Saturn The moons of Saturn are numerous and diverse, ranging from tiny moonlets only tens of meters across to enormous Titan, which is larger than the planet Mercury. Saturn has 83 moons with confirmed orbits that are not embedded in its rings—of ...

Dione Dione may refer to: Astronomy *106 Dione, a large main belt asteroid *Dione (moon), a moon of Saturn *Helene (moon), a moon of Saturn sometimes referred to as "Dione B" Mythology *Dione (Titaness), a Titaness in Greek mythology *Dione (mythology) ...

, Evander is a multi-ringed basin, * On

Mercury Mercury commonly refers to: * Mercury (planet), the nearest planet to the Sun * Mercury (element), a metallic chemical element with the symbol Hg * Mercury (mythology), a Roman god Mercury or The Mercury may also refer to: Companies * Merc ...

, Caloris Basin, surrounded by Caloris Montes is a multi-ringed basin, * The Earth's Moon, Mare Orientale is a multi-ringed basin, created by an impactor perhaps in diameter traveling at , or about , * On Jupiter's moon Callisto, Valhalla is a multi-ringed basin.

References

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External links and references

Transition from complex craters to multi‐ringed basins on terrestrial planetary bodies: Scale‐dependent role of the expanding melt cavity and progressive interaction with the displaced zone

Retracing the origins of a massive, multi-ring crater
Impact craters Impact geology

The structure of multi-ring basins

Formation

Examples

See also

References

External links and references