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Why do silica-poor magmas produce broad volcanoes with gentle slopes?
Wiki User
∙ 8y ago
Silica poor magma is generally low in viscosity, and is therefore more fluid. The lava can travel a great distance before solidifying, thus creating broad gentle slopes.
Rickie Glover
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What type of eruption produces a gentle flow of lava?
Shield volcanoes produce fast flowing lava. They erupt frequently, but eruptions are gentle because the lava is so thin and does not trap gas in the volcano.
Do volcanoes always extrude magmas of the same type?
No
Do volcanoes always produce lava flows?
No. Lava flow in a volcanic eruption is a factor of the temperature, chemistry, and amount of trapped gas in the lava. Highly viscous, felsic, gas charged magmas tend to explode upon eruption. Low viscosity, basaltic magmas tend to flow upon eruption.
Why do silica-poor magmasproduce broad volcanoes with general slopes?
Because low silica magmas tend to be hotter and more fluid/runny than high silica magmas.
How do mafic volcanic rocks get to Earth's surface?
Pressure from overlying crust forces mantle magmas through cracks to Earth's surface. These magmas erupt out of volcanoes, cool, and solidify into rock.
What type of eruption produces a gentle flow of lava?
Shield volcanoes produce fast flowing lava. They erupt frequently, but eruptions are gentle because the lava is so thin and does not trap gas in the volcano.
Why do silica -poor magmas produce broad volcanoes with gentle slopes?
Silica poor magma is generally low in viscosity, and is therefore more fluid. The lava can travel a great distance before solidifying, thus creating broad gentle slopes.
Do volcanoes always extrude magmas of the same type?
No
Do volcanoes always produce lava flows?
No. Lava flow in a volcanic eruption is a factor of the temperature, chemistry, and amount of trapped gas in the lava. Highly viscous, felsic, gas charged magmas tend to explode upon eruption. Low viscosity, basaltic magmas tend to flow upon eruption.
Why do silica-poor magmasproduce broad volcanoes with general slopes?
Because low silica magmas tend to be hotter and more fluid/runny than high silica magmas.
How do mafic volcanic rocks get to Earth's surface?
Pressure from overlying crust forces mantle magmas through cracks to Earth's surface. These magmas erupt out of volcanoes, cool, and solidify into rock.
Where does andesite form?
Andesite is an extrusive igneous rock found on or near volcanoes that contain intermediate magmas.
What kind of magmas are generated in places where volcanoes erupt both explosively and nonexplosively?
pillow lava.... i think
What type of magma does a composite volcano have?
Composite volcanoes can contain a wide variaty of magmas ranging from basaltic to rhyolitic.
What is the relationship in the silicon content and the viscosity of magma?
There is an inverse relationship between magma viscosity and silicon content. Lavas erupting from basaltic volcanoes (like Hawaii) have a much lower viscosity and are much hotter than those erupted by volcanoes whose magmas are rich in silicon. There may be up to 8 orders of magnitude viscosity difference between basaltic magmas (SiO2 contents or about 45 %) and rhyolitic magmas (SiO2 > 70 %).
Why are granitic magmas thicker than basaltic magmas?
granitic magmas contain more silica than basaltic magmas.
What kind of magmas produce violent volcanic eruptions?
Those that are rich in iron and magnesium.
