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rift volcano
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Cross-sectional diagram showing three tectonic plates at ocean ridges, transform faults, and a subduction zone. The image illustrates rising magma forming rift and subduction volcanoes, convection currents in the mantle, and features such as ocean trenches, extinct and hot-spot volcanoes, and the movement of plates above a molten core and low-velocity mantle layer.
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rift volcano

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Cross-sectional diagram showing three tectonic plates at ocean ridges, transform faults, and a subduction zone. The image illustrates rising magma forming rift and subduction volcanoes, convection currents in the mantle, and features such as ocean trenches, extinct and hot-spot volcanoes, and the movement of plates above a molten core and low-velocity mantle layer.
volcanism and plate tectonics Stratovolcanoes tend to form at subduction zones, or convergent plate margins, where an oceanic plate slides beneath a continental plate and contributes to the rise of magma to the surface. At rift zones, or divergent margins, shield volcanoes tend to form as two oceanic plates pull slowly apart and magma effuses upward through the gap. Volcanoes are not generally found at strike-slip zones, where two plates slide laterally past each other. “Hot spot” volcanoes may form where plumes of lava rise from deep within the mantle to Earth's crust far from any plate margins.

Rift volcanoes occur where Earth's tectonic plates are diverging, creating a gap into which magma rises. This process is closely linked to plate tectonics and is observed in locations like Iceland and the East African Rift System.12

These volcanoes typically erupt basaltic magma and can form fissure eruptions. In continental settings, such as the East African Rift, they can be more complex due to the assimilation of continental crust, leading to a wider variety of rock types and more explosive eruptions compared to those found on the ocean floor. Rift valleys themselves are often formed by normal faults, where the crust is extended and blocks of rock move downward.132

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3 Britannica Sources
  1. volcano - Rift volcanoes
  2. volcano - Subduction volcanoes
  3. normal fault

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