oceanic zone

基本解释

But geophysicists had thought that great subduction-zone earthquakes happened only where younger oceanic crust scrapes its way into the mantle.
但是在此之前，地球物理学者们认为，这种俯冲带大地震仅仅在年轻的海洋地壳挤入地幔处才可能发生。
The existence of recycled basaltic oceanic crust in the axial zone of mantle plume may be the key of the formation of giant V-Ti-magnetite deposits.
岩浆源区再循环玄武质洋壳的存在可能是该区超大型钒钛磁铁矿床形成的根本原因。
The evidences indicate that the magmas are formed by melting of pyrolite and eclogite (ancient basaltic oceanic crust) in the axial zone of mantle plume.
这说明它们是在地幔柱轴部，由地幔岩和榴辉岩（古玄武质洋壳）组成的源区产生的岩浆形成的。

Instead of occurring at a plate boundary along an area called a subduction zone, where one tectonic plate is diving beneath another, this earthquake occurred in the middle of an oceanic plate, where the faults in the crust essentially moved from side to side instead of up and down.
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