hazards -nature of volcanoes

Question 1

what are volcanoes?

Answer 1

.landforms that are built above an opening in the earths crust by an accumulation of eruptive products eg -lava, tephra

Question 2

what is meant by vulcanicity?

Answer 2

.refers to all volcanic activities related to magma being forced into the crust

Question 3

which plate boundaries have volcanoes?

Answer 3

.constructive -oceanic and oceanic
.constructive -continental and continental
.destructive subduction
.intraplate -hot spot

Question 4

how does magma reach the surface at a constructive -oceanic and oceanic plate margin?

Answer 4

.gap in the earths crust due to both plates moving away from each other

Question 5

what type of magma comes from a volcano at a constructive -oceanic and oceanic plate margin?

Answer 5

.effusive (runny)

Question 6

what are the characteristics of the lava at a volcano at a constructive -oceanic and oceanic plate margin?

Answer 6

.basaltic (low silica content)

Question 7

what is the frequency of eruptions at a constructive -oceanic and oceanic plate margin?

Answer 7

.high frequency

Question 8

what is the type of eruption at a constructive -oceanic and oceanic plate margin?

Answer 8

.gentle, less explosive

Question 9

what is the form of volcano that occurs at a constructive -oceanic and oceanic plate margin?

Answer 9

.shield volcano
.submarine volcano

Question 10

what is the place example of the volcano that occurs at a constructive -oceanic and oceanic plate margin?

Answer 10

.mid atlantic ridge

Question 11

how does magma reach the surface at a constructive -continental and continental plate margin?

Answer 11

.through fissures -a gap in the earths surface

Question 12

what type of magma occurs at a constructive -continental and continental plate margin

Answer 12

.viscous (thick)

Question 13

what are the characteristics of the lava at a constructive -continental and continental plate margin?

Answer 13

.high silica content

Question 14

what is the frequency of an eruption of a volcano at a constructive -continental and continental plate margin?

Answer 14

.low frequency

Question 15

what type of eruption occurs at a constructuve -continental and continental plate margin?

Answer 15

.explosive

Question 16

what type of form of volcanoes occurs at a constructive -continental and continental plate margin?

Answer 16

.composite cone volcano

Question 17

how does magma reach the surface at a destructive subductive plate margin?

Answer 17

.magma finds its way up through cracks and weaknesses caused by the pressure

Question 18

what type of magma is present at a destructive subduction plate margin?

Answer 18

.viscous -thick and sticky

Question 19

what are the characteristics of the lava at a destructive subduction plate margin?

Answer 19

.high silica content

Question 20

what is the frequency of eruption at a destructive subduction plate margin?

Answer 20

.low frequency

Question 21

what type of eruption occurs at a destructive subduction plate margin?

Answer 21

.highly explosive -due to high friction and heat from the mantle

Question 22

what type of volcano occurs at a destructive subduction plate margin?

Answer 22

.cone composite volcano

Question 23

where do volcanoes over hot spots occur?

Answer 23

.intraplate

Question 24

what causes a volcano to occur over a hot spot?

Answer 24

.magma plume

Question 25

how does magma reach the surface in a hot spot?

Answer 25

.through the plume

Question 26

what type of lava occurs from a volcano over a hot spot?

Answer 26

.basaltic .effusive

Question 27

what is the frequency of volcanoes that form over hot spots?

Answer 27

.high frequency -gently continuous eruptions

Question 28

what type of volcanoes occur over hot spots?

Answer 28

.fissure .shield

Question 29

what is an example of a volcano occurring over a hot spot?

Answer 29

.hawaii