EARTH SCIENCE
VOLCANOES
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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pyroclastic flow
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mudflows
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ash fall
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lava flows
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Detailed explanation-1: -A pyroclastic flow is extremely hot, burning anything in its path. It may move at speeds as high as 200 m/s.
Detailed explanation-2: -Areas as far as 15 km (10 mi) from an explosive eruption could be swept by hot, fast-moving pyroclastic flows and surges.
Detailed explanation-3: -Composite volcanoes, sometimes known as strato volcanoes, are steep sided cones formed from layers of ash and [lava] flows. The eruptions from these volcanoes may be a pyroclastic flow rather than a flow of lava. A pyroclastic flow is a superheated mixture of hot steam, ash, rock and dust.
Detailed explanation-4: -These heavier-than-air flows race down the sides of a volcano much like an avalanche. Reaching speeds greater than 100 kilometers per hour (60 miles per hour) and temperatures between 200° and 700° Celsius (392°and 1292° Fahrenheit), pyroclastic flows are considered the most deadly of all volcano hazards.