A multi-ringed basin (also a multi-ring impact basin) is not a simple

bowl-shaped 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 craters ...

, or a peak ring crater, but one containing multiple concentric

topographic Topography is the study of the forms and features of land surfaces. The topography of an area may refer to the land forms and features themselves, or a description or depiction in maps. Topography is a field of geoscience and planetary scie ...

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 resembling rings on a bull's-eye. 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 The rim or edge of an impact crater is the part that extends above the height of the local surface, usually in a circular or elliptical pattern. In a more specific sense, the rim may refer to the circular or elliptical edge that represents the up ...

, 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 reveal ...

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 of ...

, 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 language, Spanish: México), officially the United Mexican States, is a List of sovereign states, country in the southern portion of North America. It is borders of Mexico, bordered to the north by the United States; to the so ...

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 a ...

has a sufficient area to have been a multi-ringed basin, * On the largest moon of Jupiter, Ganymede, Anubis Crater is a multi-ringed basin, * On the moon of Saturn, 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 Su ...

, surrounded by

Caloris Montes The Caloris Montes (Latin for "Heat's Mountains") are a range of mountains on Mercury. They are a system of linear hills and valleys that extend more than 1000 km to the northeast from the mountainous rim of Caloris Basin in the Shakespeare qu ...

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-thousand ...

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 of ...

Callisto,

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 e ...

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