2017年11月28日
A Low Viscosity Lunar Magma Ocean Forms a Stratified Anorthitic Flotation Crust With Mafic Poor and Rich Units
Geophysical Research Letters
- ,
- ,
- ,
- ,
- 巻
- 44
- 号
- 22
- 開始ページ
- 11,282
- 終了ページ
- 11,291
- 記述言語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1002/2017GL075703
- 出版者・発行元
- American Geophysical Union ({AGU})
Much of the lunar crust is monomineralic, comprising >98% plagioclase. The prevailing model argues the crust accumulated as plagioclase floated to the surface of a solidifying lunar magma ocean (LMO). Whether >98% pure anorthosites can form in a flotation scenario is debated. An important determinant of the efficiency of plagioclase fractionation is the viscosity of the LMO liquid, which was unconstrained. Here we present results from new experiments conducted on a late LMO-relevant ferrobasaltic melt. The liquid has an exceptionally low viscosity of 0.22-0.29+0.11 to 1.45-0.82+0.46 Pa s at experimental conditions (1,300–1,600°C; 0.1–4.4 GPa) and can be modeled by an Arrhenius relation. Extrapolating to LMO-relevant temperatures, our analysis suggests a low viscosity LMO would form a stratified flotation crust, with the oldest units containing a mafic component and with very pure younger units. Old, impure crust may have been buried by lower crustal diapirs of pure anorthosite in a serial magmatism scenario.
- リンク情報
- ID情報
-
- DOI : 10.1002/2017GL075703
- ISSN : 0094-8276
- eISSN : 1944-8007
- ORCIDのPut Code : 43577664
- SCOPUS ID : 85034639505