- Lunar dome
A lunar dome is a type of
shield volcano that is found on the surface of theEarth 'sMoon . They are typically formed by highly viscous, possiblysilica -richlava , erupting from localized vents followed by relatively slow cooling. Lunar domes are wide, rounded, circular features with a gentle slope rising in elevation a few hundredmeter s to the mid-point. They are typically 8-12 km in diameter, but can be up to 20 km across. Some of the domes contain a small craterlet at the peak.Some of the domes have been shown to consist of the same materials as the
lunar maria . Thus they could be created by some mechanism that differs from the mare-forming flows. It is thought that these domes are formed from a smallermagma chamber that is closer to the surface than is the case for a mare. This results in a lower pressure, and so the lava flows more slowly. Themagma wells up through a crack in the surface, but the flow eventually concentrates through one primary vent. This concentration can then result in a vent crater at the peak of the dome.There are concentrations of lunar domes near the craters Hortensius, Marius and T. Mayer, and across the top of
Mons Rümker . Solitary lunar domes are also found on the near side, including Kies Pi (π), Milichius Pi (π),Mons Gruithuisen Gamma (γ) and Delta (δ), and a dome near the craters Gambart C, Beer and Capuanus. Omega Cauchy (ω) and Tau Cauchy (τ) form a pair of domes near the crater Cauchy. Likewise near Arago are the domes Arago Alpha (α) and Arago Beta (β).References
* Lionel Wilson and James W. Head, " [http://www.agu.org/pubs/crossref/2003/2002JE001909.shtml Lunar Gruithuisen and Mairan domes: Rheology and mode of emplacement] ", "Journal of Geophysical Research", vol. 108,
2003 .External links
* [http://www.geocities.com/kc5lei/lunar_dome.html Marvin W. Huddleston, ALPO Lunar Dome Survey Coordinator's web page on Lunar Domes]
* [http://www.lpl.arizona.edu/~rhill/alpo/lunar.html Association of Lunar & Planetary Observers, Lunar Section]
* [http://digilander.libero.it/gibbidomine/ GLR Group Website]
* [http://luna.uai.it/domi/lunar_domes.htm UAI Lunar Dome Introduction]
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