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How did the breakup of Pangea create new ocean basins?

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Earth's lithosphere and upper mantle — oceanic crust A cross section of Earth's outer layers, from the crust through the lower mantle.

The breakup of the supercontinent Pangea and the subsequent creation of new ocean basins are driven by the process of plate tectonics.

The process begins with continental rifting, where the upwelling of magma causes the lithosphere to uplift and stretch. This creates fractures that are invaded by ascending magma, which pries continental blocks apart and forms a rift valley. As the rift widens, the continental crust thins until the plates separate completely.

Once separation occurs, the ascending partial melt cools and crystallizes to form new oceanic crust. Because this melt is basaltic, an oceanic ridge develops at the site of the former rift. Through seafloor spreading, the new crust spreads laterally away from these ridges, continuously increasing the breadth of the emerging ocean basin. This mechanism allowed for the formation of the Atlantic and Indian oceans as Pangea fragmented in distinct stages starting approximately 200 million years ago.1234