Most of the rocks might be originally fragments of oceanic rocks introduced during plate subduction.

这些岩石大部分可能为板块俯冲过程中带入的大洋岩石残片。

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They are probably related to the subduction of the Paleo-Asia Oceanic plate, and their intrusion resulted in the contact metamorphism of the Majiajie Group.

它们的形成可能与晚古生代古亚洲洋的消减作用有关，该期花岗岩的就位导致马家街群发生了接触变质作用。

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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.

MSN: Why this Indonesia quake didn't spark a monster tsunami

Although they are sometimes produced by landslides on the seafloor, significant tsunamis are typically created by subduction earthquakes, when one massive oceanic plate suddenly lurches deeper beneath another plate, shoving up a huge section of the seafloor.

MSN: Why this Indonesia quake didn't spark a monster tsunami