Evolution of the earth's crust: Evidence from comparative planetology
Evolution of the earth's crust: Evidence from comparative planetology
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地壳的演化：来自比较行星学的证据
DOI：
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发表时间：
1973
期刊：
影响因子：
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通讯作者：
P. Lowman
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文献类型：
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作者：
P. Lowman
来自阿波罗、水手和金星任务的地球化学数据和轨道摄影与陆地地质证据相结合，研究了地球为什么有两种截然不同的地壳类型(海洋和大陆)的问题。以下是陆壳演化的提纲。在地球历史早期，由火成岩作用形成了一个中等到酸性的地壳，富含铝；在一些屏蔽区以花岗岩和斜长片麻岩的形式保留了部分。这个地壳被主要的撞击和构造过程打破了，随后是类似于月球玛丽亚和火星北半球平坦平原的玄武岩喷发。随后发生了海底扩张和俯冲，在此期间，早期大陆地壳的一部分和由此衍生的沉积物被推到剩余的大陆地壳之下。今天，这一进程在安第斯/秘鲁-智利战壕系统等区域得到了示范。底侵可能是大致同心的，底侵的唾液物质中放射性元素含量较高，最终可能导致区域变质和岩浆作用的同心带。
Geochemical data and orbital photography from Apollo, Mariner, and Venera missions were combined with terrestrial geologic evidence to study the problem of why the earth has two contrasting types of crust (oceanic and continental). The following outline of terrestrial crustal evolution is proposed. A global crust of intermediate to acidic composition, high in aluminum, was formed by igneous processes early in the earth's history; portions survive in some shield areas as granitic and anorthositic gneisses. This crust was fractured by major impacts and tectonic processes, followed by basaltic eruptions analogous to the lunar maria and the smooth plains of the north hemisphere of Mars. Seafloor spreading and subduction ensued, during which portions of the early continental crust and sediments derived therefrom were thrust under the remaining continental crust. The process is exemplified today in regions such as the Andes/Peru-Chile trench system. Underplating may have been roughly concentric, and the higher radioactive element content of the underplated sialic material could thus eventually cause concentric zones of regional metamorphism and magmatism.