Explosive eruptions

• Found at convergent plate boundaries, with rhyolite and andesite, creating highly viscous lava, with violent eruptions, emitting gas dusr, ash lava bombs and tephra.
• Tend to have long periods of no activity, and are steep sided strato-volcanoes, such as mount st helens.
• Strato volcanoes are made up of layers of lava, and have dykes which are igneous rock layers cutting across beds of rocks. And sills are igneous rock layers running between bedds of rock
• Due to hihgly viscous magma, this can form a plug, creating pressure, and thus an explosive eruption.
• Calderas are volcanic craters, created when an erutpion destroys the cone of the volcano.
• Lava domes are the result of slow lava which quickly solidifies over the vent.