How does magma form at divergent tectonic plate boundaries?

Sources are from NationalGeographic.org

"Decompression melting involves the upward movement of Earth's mosty-solid mantle. ... Decomposition melting often occurs at divergent boundaries, where tectonic plates separate. The rifting movement causes the buoyant magma below to rise and fill the space of the lower pressure. The rock then cools into new crust."

I got this from NationalGeographic.org

"Decompression melting involves the upward movement of Earth's mosty-solid mantle..."The rifting movement causes the buoyant magma below to rise and fill the space of the lower pressure. The rock then cools into new crust."
I hope this helps you!!!:)

Answer primary waves;