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Non-explosive volcanism

Part of David S. and Ruth L. Gottesman Hall of Planet Earth.

NonExplosive Volcanism

Exhibition Text

Effusive volcanism and plate tectonics
People associate volcanoes with spectacular explosive eruptions, yet most volcanoes erupt basalt, a fluid lava from the mantle that erupts effusively and forms flows. Most basaltic lava erupts on the ocean floor, along an undersea mountain chain called the mid-ocean ridge system. Basaltic lava also erupts at “hot spots,” where molten rock, or magma, forms in plumes of hot rock that rise from deep in the Earth to penetrate a moving plate above. Over time, a chain of volcanoes forms, such as the Hawaiian Islands, aligned along the direction of the plate’s movement.

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