DOI: 10.1016/j.epsl.2020.116426
论文题名: On the eruptive origins of lunar localized pyroclastic deposits
作者: Keske A.L. ; Clarke A.B. ; Robinson M.S.
刊名: Earth and Planetary Science Letters
ISSN: 0012821X
出版年: 2020
卷: 547 语种: 英语
中文关键词: basaltic volcanism
; explosive volcanism
; lunar volatiles
; Moon
; Moon, surface
; volcanism
英文关键词: Cameras
; Moon
; Optical projectors
; Orbits
; Spectroscopic analysis
; Volcanoes
; Digital terrain model
; Eruption mechanisms
; In compositions
; Lunar reconnaissance orbiters
; Material proportion
; Melt inclusions
; Morphometry
; Pyroclastic deposits
; Deposits
; comparative study
; crater
; degassing
; lunar crust
; Moon
; morphometry
; pyroclastic deposit
; volcanic eruption
; volcanism
英文摘要: Localized pyroclastic deposits (LPDs) are low-albedo accumulates of pyroclastic material with distinct positive topographic signatures that are found dominantly along highland-mare boundaries. Previous workers hypothesized that LPDs represent products of a lunar equivalent of Vulcanian-style eruptions, based in part on the observation that some of the deposits in Alphonsus Crater have large vent volumes in comparison with their deposit volumes, indicating a low proportion of juvenile material in the deposits. The objective of this study is to better understand eruption mechanisms by determining how the proportion of juvenile material, as calculated using deposit and vent volumes, varies among LPDs in Alphonsus Crater and elsewhere on the Moon using contemporary data and methods. Deposit and vent volumes for 23 LPDs from eleven sites were calculated by differencing current and modeled pre-eruption surfaces using digital terrain models (DTMs) derived from Lunar Reconnaissance Orbiter Camera Narrow Angle Camera (LROC NAC). Results show that LPDs have a wide range of juvenile proportions, many of which are more juvenile-rich than previously thought. Additionally, there is a positive relationship between juvenile material proportion and deposit volume and thickness, and a positive relationship between juvenile volume and dispersal area. LPDs also bear a broad range of thinning profiles which span a range of multiple eruption types on Earth. These findings, along with previous studies employing spectroscopic analysis of these deposits, indicate there is greater diversity among LPDs in composition and morphometry than previously understood, and that previously published simplified Vulcanian models may apply only to the deposits containing the least amount of juvenile material, with all others perhaps requiring a combination of multiple eruptive mechanisms. Furthermore, dynamic model results suggest that the most widespread lunar deposits in this study were formed by magma containing 2000–5000 ppm of dissolved volatiles, consistent with recent estimates via melt inclusion analysis, but contrary to long-held ideas that the Moon was largely degassed during its formation. © 2020 Elsevier B.V. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/165075
Appears in Collections: 气候变化与战略
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作者单位: School of Earth and Space Exploration, Arizona State University, P.O. Box 876004, Tempe, AZ 85287-6004, United States
Recommended Citation:
Keske A.L.,Clarke A.B.,Robinson M.S.. On the eruptive origins of lunar localized pyroclastic deposits[J]. Earth and Planetary Science Letters,2020-01-01,547