Volcanic Eruptions
Describe Pyroclastic Material and Lava Flows
What is Pyroclastic Material?
Volcanic Ash and Dust
Volcanic Ash are particles that are less then 2 mm in diameter while Volcanic Dust is less than 0.25 mm in diameter and they both surround a volcano immediately once it settles on land.
Lapilli
Lapilli are large particles that are less than 64 mm in diameter which mostly fall near a volcanoes vent.
Volcanic Bombs and Blocks
Volcanic bombs are large clots of lava are thrown out of an erupting volcano, when the lava cools it develops into a round or spindle shape. Volcanic blocks are large pyroclastic materials that form from solid rock and are blasted from the vent.
What are the types of Mafic Lava Flow?
Types of Mafic Lava
Pahoehoe lava
Pahoehoe is the least viscous type of mafic lava. It forms wrinkly volcanic rock when it cools.
Aa lava
Is more viscous than pahoehoe lava and forms sharp volcanic rock when it cools.
Blocky lava
Blocky lava is the most viscous type of mafic lava and forms chunky volcanic rock when it cools.