Lunar Mare volcanism : Lateral heterogeneities in volcanic activity and relationship with crustal atructure
Lunar Mare volcanism : Lateral heterogeneities in volcanic activity and relationship with crustal atructure
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月海火山活动：火山活动的横向异质性及其与地壳结构的关系
DOI：
10.1144/sp401.11
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
Ohtake
中科院分区：
文献类型：
--
作者：
Morota;Ishihara;Sasaki;Goossens;Matsumoto;Noda;Araki;Hanada;Tazawa;Kikuchi;Ishikawa;Tsuruta;Kamata;Otake;Haruyama;Ohtake
月海玄武岩在空间上分布不均匀，其丰度在月球正面和背面存在差异。虽然海的不对称性归因于低密度斜长岩地壳的厚度变化，但月球岩浆的喷发机制仍不清楚。本文利用SELENE （Kaguya）和重力恢复与内部实验室（Gravity Recovery and Interior Laboratory）航天器获得的地质和地球物理资料，研究了岩浆分布与地壳厚度的关系，并定量地重新评价了斜长岩地壳对岩浆喷发的影响。我们发现在地壳厚度上限处存在横向非均质性，使岩浆能够向地表挤压。在Procellarum KREEP Terrane中，地表产热元素的丰度非常高，岩浆可以在地壳厚度低于30公里的区域喷发。相比之下，在其他近侧区域，岩浆喷发仅限于地壳厚度低于20公里的区域，在南极-艾特肯盆地约为10公里，在远侧Felspathic Highland Terrane约为5公里。这种非均质性可能是由于月幔岩浆生产和/或地壳密度的横向变化造成的。
Lunar mare basalts are spatially unevenly distributed, and their abundances differ between the nearside and farside of the Moon. Although mare asymmetry has been attributed to thickness variations in the low-density anorthositic crust, the eruptive mechanism of lunar magma remains unknown. In this study, we investigate the relationship between mare distribution and crustal thickness using geological and geophysical data obtained by the SELENE (Kaguya) and the Gravity Recovery and Interior Laboratory spacecraft, and quantitatively re-evaluate the influence of the anorthositic crust on magma eruption. We identify a lateral heterogeneity in the upper limit of crustal thickness that allows magma extrusion to the surface. In the Procellarum KREEP Terrane, where the surface abundances of heat-producing elements are extremely high, magmas can erupt in regions of crustal thickness below about 30 km. In contrast, magma eruptions are limited to regions of crustal thickness below about 20 km in other nearside regions, around 10 km in the South Pole–Aitken Basin and approximately 5 km in the farside Felspathic Highland Terrane. Such heterogeneity may result from lateral variations in magma production in the lunar mantle and/or crustal density.