One Note - vulcanicity

Question 1

what is the characteristics of basaltic lava?

Answer 1

Low silica content, low viscosity, flows easily over large areas, associated with shield volcanoes.

Question 2

what is the characteristics of andesitic lava?

Answer 2

Intermediate silica content and viscosity, flows less easily, associated with composite volcanoes.

Question 3

what is the characteristics of rhyolitic lava?

Answer 3

High silica content, highly viscous, traps gases, associated with explosive eruptions and caldera-forming volcanoes.

Question 4

what is the temperature for basaltic lava?

Answer 4

Basaltic: ~1,000–1,200°C

Question 5

what is the temperature for andesitic lava?

Answer 5

Andesitic: ~800–1,000°C

Question 6

what is the temperature for rhyolitic lava?

Answer 6

Rhyolitic: ~650–800°C

Question 7

how does silica effect the nature of lava?

Answer 7

The more silica the more acidic and viscous and subsequently leads to more dangerous explosions.

Question 8

what is volcanos measured by?

Answer 8

logarithmic volcano explosivity index

Question 9

Interpret the relationship between the VEI and the nature of the volcanic eruption.

Answer 9

The higher the VEI the greater the intensity and magnitude and the more explosive it is.

But the higher the VEI score its usually less frequent but the scale of the eruption is much larger.