Science Volcanoes
Order by
20 terms
Terms | Definitions |
|---|---|
 Most Volcanoes occur along..... | diverging plate boundaries such as the mid-ocean ridge or in a subduction zones around the edges of oceans. |
| If oceanic crust collides with continental crust.... | volcanoes form. The crust melts underneath and forms magma which rises to the surface. When it hits the top a volcano forms. |
| Oceanic crust colliding with oceanic crust causes... | island arcs. This is where magma rises to the surface again-but then you get islands formed by volcanos. |
| characteristics of magma | hotter the magma more fluid it is, amount of silica also makes a difference more silica= thicker, high silica forms light colored lava called obsidian and lava, low silica forms basalt. |
| type of volcanic eruption | the silica content of magma determines whether the volcanic eruption is quite or explosive. |
| quite eruptions | magma flows easily, gasses bubble out gently, thin runny lava oozes quietly from a vent two types of lava. |
| Pahoehoe | fast hot moving lava, looks like solid mass if wrinkles or rope like coils. |
| aa | cooler lava and slower moving it forms a rough surface of jagged lava chunks |
| explosive eruption | if magma is thick and sticky a volcano erupts _________ thick magma doesn't come out well, plugs up like a cork, nothing escapes, over time it explodes. |
| geyser | is a fountain of water and steam the erupts from the ground |
| Cinder cone volcano | a steep, cone shaped hill or mountain is called a __________ , If a volcanoes lava is thick and stiff it may produce ash, cinders, and bombs, these pile up around the vent |
| composite volcano | lava flows alternate with explosive eruptions of ash, cinder and bombs, lava-ash lava-ash lava-ash, tall cone shaped mountains in which layers of lava alternate with layers of ash are _________ |
| calderas | enormous eruptions may empty the main vent and the magma chamber beneath. It becomes hollow, with nothing supporting it it collapses, the huge hole is called a __________ |
| batholith | a mass of rock formed when a large body of magma cools inside the crust |
| dome mountain | forms when rising magma is blocked y horizontal layers of rock the magma forces the layers of rock to bend upward into a domed shape . |
| most volcanoes occur along | diverging plate boundaries, such as the mid-ocean ridge or in subduction zones around the edges of oceans. |
| during a volcanic eruption ........ | the gases dissolved in magma rush out carrying the magma with them |
| silica | is a material formed from oxygen and silicon |
| pyroclastic flow | occurs when an explosive eruption hurls out ash, cinders, and bombs. |
| geothermal energy | water heated by magma can provide a clean reliable energy source |
First Time Here?
Welcome to Quizlet, a fun, free place to study. Try these flashcards, find others to study, or make your own.