Volcanoes and Earthquake

Volcanoes

• release magma

• about 1,500 active volcanoes on the planet (1 eruption in recorded history)

• 50 volcanic eruption every year

Basalt

48%-55%

Andesite

55%-60%

Dacite

60%-70%

Rhyolite

70%-77%

Cinder Cones

• mildly explosive

• constructed from fountains of lava that rain around the vent

Shield Volcanoes

• mildly explosive

• really big, long duration cinder cones

Composite Volcanoes

• mild to highly explosive

• build up over time with alternating ash fallouts and lava flows

• tendency to generate extremely violent events mixed with more moderate events

Lava Domes

• non-explosive

• highly viscous eruption that build internally and externally

Calderas

• highly explosive

• lead to structural collapse from an emptied magma chamber

Lahars

hot or cold mixture of water and rock fragments flowing down the slope and into river valleys

Pyroclastic Flows

fluidized masses of rock fragments and gases that move rapidly in response to gravity

C02 Emission

release of C02 from buried magma into the atmosphere through faults, fissures, and lakes

Fertile Soils

enriched soils from mineral rich volcanic ashfalls

Geothermal Energy

magma in the earth heats groundwater and the steam is used to power generators

New Land

lava flows from continents into oceans can generate new land for development