As the plates spread apart, the lithosphere, or crust, is moved aside like a lid, allowing molten rock from the liquid asthenosphere to seep through.

板块分离时，岩石圈或地壳象盖子般移到一旁，液态软流层中的熔岩渗溢而出。

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Seamounts form from magmatic eruptions, which occur when lava seeps up to the crust through the partially-melted sub-layer, known as the asthenosphere, in the mantle.

火山岩透过地幔中部份熔融的软流层渗入到地壳，岩浆喷发，海山由此形成。

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That is one of the possible reasons why there is no "high-conductive layer of the upper mantle" in the MT profile from Yingxian to Shanghe, which images the asthenosphere electrical characters.

这也许正是根据现今应县—商河剖面上大地电磁的探测结果看不出来存在通常所说的反映“软流圈”电性特征的“上地幔高导层”的原因。

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