Question

Lava erupts through long cracks in the ground, also called what?

Answer 1

fissures

At divergent plate boundaries hot mantle rock rises into the space where the plates are moving apart. As the hot mantle rock rises, it goes from higher to lower pressure. This is because there is no longer the weight of all the rock above it. Lower pressure lowers the melting temperature of the rock  2 in the previous section . This is why there is volcanism at divergent plate boundaries. Lava erupts through long cracks in the ground, or fissures.