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 An impact crater is a circular depression in the surface of a solid astronomical object formed by the hypervelocity impact of a smaller object. In contrast to volcanic craters, which result from explosion or internal collapse, 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

bull's-eye The bullseye or bull's eye has, since 1833, been the name for the center of a target Target may refer to: Physical items * Shooting target, used in marksmanship training and various shooting sports ** Bullseye (target), the g ...

. 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 Terrace may refer to: Landforms and construction * Fluvial terrace, a natural, flat surface that borders and lies above the floodplain of a stream or river * Terrace, a street suffix * Terrace, the portion of a lot between the public sidewalk an ...

, and has slump structures inside of it. In 2016, research brought forward new theories about the

lunar mare The lunar maria (; singular: mare ) are large, dark, basaltic plains on Earth's Moon, formed by ancient asteroid impacts on the far side on the Moon that triggered volcanic activity on the opposite (near) side. They were dubbed , Latin for 'seas' ...

called

Mare Orientale Mare Orientale (Latin ''orientāle'', the "eastern sea") is a lunar mare. It is located on the western border of the near side and far side of the Moon, and is difficult to see from an Earthbound perspective. Images from spacecraft have reve ...

on Earth's

Moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width ...

, 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 Mexico ( Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guate ...

Chicxulub crater The Chicxulub crater () is an impact crater buried underneath the Yucatán Peninsula in Mexico. Its center is offshore near the community of Chicxulub, after which it is named. It was formed slightly over 66 million years ago when a large ast ...

has a sufficient area to have been a multi-ringed basin, * On the largest moon of Jupiter, 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, Evander is a multi-ringed basin, * On Mercury,

Caloris Basin Caloris Planitia is a plain within a large impact basin on Mercury, informally named Caloris, about in diameter. It is one of the largest impact basins in the Solar System. "Calor" is Latin for " heat" and the basin is so-named because the ...

, surrounded by Caloris Montes is a multi-ringed basin, * The Earth's Moon,

is a multi-ringed basin, created by an impactor perhaps in diameter traveling at , or about , * On

Jupiter Jupiter is the fifth planet from the Sun and the largest in the Solar System. It is a gas giant with a mass more than two and a half times that of all the other planets in the Solar System combined, but slightly less than one-thousandt ...

moon The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width ...

Callisto Callisto most commonly refers to: * Callisto (mythology), a nymph *Callisto (moon), a moon of Jupiter Callisto may also refer to: Art and entertainment *'' Callisto series'', a sequence of novels by Lin Carter *''Callisto'', a novel by Torsten ...

Valhalla In Norse mythology Valhalla (;) is the anglicised name for non, Valhǫll ("hall of the slain").Orchard (1997:171–172) It is described as a majestic hall located in Asgard and presided over by the god Odin. Half of those who die in combat ...

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