Earth’s Subduction May Have Been Triggered by the Same Event That Formed the Moon

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By Rachel Fritts, Eos/AGU. 

Excerpt: The giant impact that formed the Moon may also have led to extrastrong mantle plumes that enabled the first subduction event, kick-starting Earth’s unique system of sliding plates. In a new study, Yuan et al. find evidence tracing the first subduction event to the same impact that created our Moon. ...Yuan’s team explored postimpact mantle convection using both 2D and 3D thermomechanical modeling. They found that the increase in temperature at the core-mantle boundary after the giant impact could have led, over time, to strong mantle plumes—phenomena still seen today that can sometimes lead to volcanic activity far from plate boundaries.... 

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