The explanation may be in Earth's mantle, the layer of rock underlying the tectonic plates and extending down over 1,800 miles to the outer edge of Earth's iron core.

解释可能是在地球的地幔中，这是在构造板块下面的岩石层，向下延伸超过1800英里到地球铁芯的外边缘。

youdao

She takes her visit to the Galapagos, for example, as the starting point for an explanation of plate tectonics (the itchy movements of the various plates that comprise the earth's ever-shifting surface) that created these islands.

ECONOMIST: Island life