EARTH SCIENCE
VOLCANOES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Most volcanoes in the Philippines erupt violently
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Volcanoes found in the ridge system
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Highly Viscous magma inside the vent easily solidifies, forming a blockage in the crater of a volcano
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A notable example is the 1980 eruption of Mount St. Helens
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Detailed explanation-1: -Volcanoes that have very hot, low-silica magma generally erupt quietly. In a quiet eruption, lava erupts in a stream of low-viscosity lava, called a lava flow. Lava flows from a quiet eruption can travel for great distances.
Detailed explanation-2: -Effusive eruptions These eruptions are (relatively!) gentle, effusive eruptions. If a magma rises very slowly within the conduit. or throat, of the volcano, all the gas can escape. When the magma is viscous (or sticky), it can’t flow when it reaches the surface, so it builds up forming a lava dome.
Detailed explanation-3: -Lava Domes They are built by slow eruptions of highly viscous lava. They are sometimes formed within the crater of a previous volcanic eruption. Like a composite volcano, they can produce violent, explosive eruptions, but their lava generally does not flow far from the originating vent.
Detailed explanation-4: -Definition. Axial volcanic ridges (AVRs). Composite volcanic edifices, comprising an elongate, typically spreading-normal orientated topographic high, produced within the inner valleys of mid-ocean ridges, usually those that are slow spreading.