Evolution of lunar magma ocean and crust formation under initial conductive lid
Evolution of lunar magma ocean and crust formation under initial conductive lid
复制标题
初始导电盖下月球岩浆海洋演化及地壳形成
DOI：
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发表时间：
2016
影响因子：
1.8
通讯作者：
Wang Shijie
中科院分区：
文献类型：
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作者：
Xu Yingkui;Li Xiongyao;Zhu Dan;Wang Shijie
月球的早期状态被认为是月球岩浆洋(LMO)。对LMO的研究不仅对于认识月球的内部结构具有重要意义，而且可以指示月球和行星的起源。LMO的主导模型表明，当80%的LMO凝固后，斜长石开始结晶并漂浮到地表形成斜长岩地壳，整个凝固时间为月球的岩浆洋。 LMO只有几百万年。主导模型与阿波罗观测的斜长岩结晶年龄跨度为270 Myr有出入。为了解决这个问题，我们关注LMO中的温度梯度，并将热梯度下的质量传递应用于其演化。在热梯度下，最初均质的硅酸盐熔体会出现化学不均匀性，这称为热扩散。我们的工作模型是： LMO在成分上是分层的，月壳是从上部——部分结晶区形成的。斜长石An和底辟速度的计算也支持了这种地壳形成模型。
The early state of the Moon is thought to be Lunar Magma Ocean(LMO).Studies of LMO not only have significant meaning for recognizing the internal structure of the Moon,but also can be indicative for the origin of the Moon and planets.The dominated model of the LMO suggests that after 80%of the LMO solidified,plagioclase starts to crystallize and floats to the surface to form anorthositic crust and the whole solidifying time for the LMO is only several million years.The dominated model has discrepancy with the Apollo observations that crystallization age of anorthosites span 270 Myr.To solve this problem,we focus on the temperature gradient in the LMO and apply mass transport under thermal gradient to its evolution.Chemical heterogeneity can occur in the initially homogenous silicate melt under thermal gradient,which is named thermal diffusion.Our working model is:the LMO is stratified in composition,and the lunar crust is formed from the upper part-the partially crystallizing zone.Calculations of An of plagioclase and the speed of diapirs also support this crust-forming model.