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，地球物理學者們認爲，這種頫沖帶大地震僅僅在年輕的海洋地殼擠入地幔処才可能發生。
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.
巖漿源區再循環玄武質洋殼的存在可能是該區超大型釩鈦磁鉄鑛牀形成的根本原因。
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.
這說明它們是在地幔柱軸部，由地幔巖和榴煇巖（古玄武質洋殼）組成的源區産生的巖漿形成的。

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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