Volcanoes

Question 1

what decides how bad a volcano is

Answer 1

VEI
tephra
column height

Question 2

What is a mega colossal volcano?

Answer 2

An 8+ on the VEI

They are world changing.

Question 3

how is a volcano formed at a convergent destructive plate boundary

Answer 3

plate is subducted and destroyed in the benioff zone.

the magma squeezes up cracks in the continental plate creating volcanoes.

Question 4

how are volcanoes created at a divergent boundary - continental rift.

Answer 4

the plates move apart, creating a thinner area of the lithosphere.

the magma finds gaps in this thinner plate, creating volcanoes

Question 5

how are volcanoes created by plumes

Answer 5

the plume finds a weaker point of the lithosphere and penetrates. creating a volcano

Question 6

what are the two types of magma

Answer 6

basaltic

rhyolitic

Question 7

what makes magma basaltic

Answer 7

magma that dosent mix with any plates or substances

Question 8

what makes magma rhyolitic

Answer 8

basaltic magma that mixes with a subducted plate.

Question 9

what are the three types of eruption

Answer 9

plinian

pelean

hawaiian

Question 10

describe a plinian eruption

Answer 10

biggest
rhyolitic lava
shoots straight up then spreads out
not much lava

Question 11

describe a pelean eruption

Answer 11

pyroclastic flow so lots of tephra
middle lava type
not much lava

Question 12

describe a hawaiian eruption

Answer 12

non viscous fast moving lava
basaltic lava

Question 13

list the volcanoes is danger order

Answer 13

1. composite
2. cinder cone
3. shield
   ?. caldera (can be any volcano type)

Question 14

describe a shield volcano

Answer 14

basaltic magma
huge and flat with steady slopes
hawaiian eruption

Question 15

describe a composite volcano

Answer 15

rhyolitic lava
cone shaped
plinian eruption
most dangerous

Question 16

describe a cinder cone volcano

Answer 16

usually rhyolitic lava
shaped by its own old tephra
pelean eruption

Question 17

describe a caldera volcano

Answer 17

any lava type
huge crater formed from either a shield volcano being too heavy and falling in on itself or a huge composite volcano explosion
sometimes has a lake

Question 18

compare basaltic and rhyolitic lava

Answer 18

basaltic:
- low gas content
- low viscosity so faster
- higher temp 1000-1200 C

rhyolitic:
- high gas content so explosive
- high viscosity
- cooler temp 650-800 C

Question 19

whats an intrusive land form and give an example

Answer 19

a landform formed inside of earth

batholith

Question 20

whats an extrusive land forem and give an example

Answer 20

formed on the surface of the earth

volcano

Question 21

how is a batholith formed

Answer 21

magma chamber from a destructive boundary stops being fueled as the oceanic plate gets fully destroyed.
it solidifies and the rock above is eroded exposing the harder batholith rock