Understanding Volcanoes questions Name:_________________________ 1. What important functions do volcanoes perform for the Earth? Regulates Earth’s internal temperature & pressure. Renews land (creates igneous rock). Cooling vents. 2. What is the difference between magma & lava? Magma is underneath the ground. Lava is above-ground. 3. What is the ring of fire? A ring of volcanoes in the Pacific. 10,000 mile belt of volcanoes that marks the borders of several Pacific-area tectonic plates. 4. What is a fumarole? A hole or vent in the ground near a volcano that emits gases from the volcano 5. How do you think monitoring ground motion, geochemistry and lava flows helps scientists draw conclusions about volcanic activity? It may help us predict volcanic activity, and the type of volcanic activity. 6. Could a volcanic eruption ever be controlled? Probably not. 7. What is subduction? The edge of one crustral plate is forced under another plate. 8. What is a pyroclastic flow? A volcanic eruption consisting mainly of fragmented rock. This type is extremely dangerous. Example: Mount Saint Helens. 9. What is tephra? Post-eruption layers of land composed of volcanic lava and fragmented rock. 10. What is ground deformation? Bulges in the Earth’s surface caused by swelling in a volcano’s magma chamber.