volcanoes

Question 1

what are volcanoes linked to?

Answer 1

plate tectonics and plate boundaries.

Question 2

how many active volcanoes are there in the world?

Answer 2

500

Question 3

what is the youngest volcano and when did it come from the ground?

Answer 3

Paricutin 1943

Question 4

which volcano caused the year without summer?

Answer 4

Tambora, 1815

Question 5

how many deaths were caused by Tambora?

Answer 5

60,000

Question 6

how many deaths occurred with Krakatau?

Answer 6

36,417

Question 7

how many deaths occurred with Pelee?

Answer 7

28,800

Question 8

when did Pelee occur?

Answer 8

1902

Question 9

when did Krakatau occur?

Answer 9

1883

Question 10

what is the eruption magnitude related to?

Answer 10

logarithmically to the mass or volume of ejected material.

Question 11

what magnitude is Yellowstone?

Answer 11

+9

Question 12

which volcanoes are supervolcanoes?

Answer 12

yellowstone, Tambora, Mt St Helens

Question 13

what are the different types of volcanoes?

Answer 13

shield volcanoes, stratovolcanoes, calderas and caldera complexes.

Question 14

what lava does a shield volcano have?

Answer 14

balsaltic lava

Question 15

what are the eruptions like in a shield volcano?

Answer 15

smaller, geographically contrainted eruptions, only explosive if water enters the vent.

Question 16

what percentage of lava in in shield volcanoes?

Answer 16

90%, other is pyroclastic material

Question 17

what percentage of the earth individual volcanoes are stratovolcanoes?

Answer 17

60%

Question 18

what are the composition of stratovolcanoes?

Answer 18

andesite and dacite lava, which is more vocois than balsalt, allows gas pressure to build.

Question 19

what are the eruptions like in stratovolcanoes?

Answer 19

more explosive eruptions due to the gas build-up. very dangerous

Question 20

what percentage is lava in stratovolcanoes?

Answer 20

50% lava and 50% pyroclastic material

Question 21

what type of eruptions are calderas?

Answer 21

most explosive volcanoes- supervolcanoes. then they erupt, they collapse on themselves.

Question 22

which volanoes are calderas?

Answer 22

Koba, Yellowstone, Mt Vesuvius, Campi Flegrei.

Question 23

what are the 4 types of eruptions?

Answer 23

Hawaiian, Stromolian, Vulcanian, Plinian.

Question 24

what is a Hawaiin eruption?

Answer 24

basaltic, fluid lava, least threatening, few explosions, can last week. destroys everything in its path and ruins land

Question 25

what is a Stromolian eruption?

Answer 25

discrete explosions at periods or seconds, to hours. ash columns and abundant ballistic debris, bomb lapilli and ash.

Question 26

what is a Vulcanian eruption?

Answer 26

highly explosive, short lived, black ash and stream laden eruption.

Question 27

what is a Plinian eruption?

Answer 27

the worst eruption, widely dispersed events, explosive areas of impacts. highly eruptive columns. produced Tephra and Volcanic Ash. debris avalanches, landslides, surges, blasts etc.

Question 28

what happened in Montserrat?

Answer 28

eruptions began in July 1995, much of the island was evacuated. 1997- 19 people died n another eruption.

Question 29

in Mountserrat, what was the main town buried in?

Answer 29

Pyroclastic flow.

Question 30

what is volcano monitoring?

Answer 30

volcano observatories located in key regions, the key role in monitoring and early warning. detecting warning signs and provide the best mean to anticipate and mitigate against potential disasters.

Question 31

where should volcano observatories be set up?

Answer 31

where there is threatened human populations and where it is possible to predict eruptive behaviour.

Question 32

what lessons did they learn from Monserrat about basic sessions on human nature and society?

Answer 32

scientists, governors and local politicians tend to differ on what level of risk is acceptable. volcanology is an uncertain science, politicians dislike uncertainty. need good scientific information through fully communicated. buy-in trust regarding the management process.

Question 33

when was the first Mt St Helen eruption?

Answer 33

1980, 57 people killed

Question 34

what was unusual about the Mt St Helen eruption?

Answer 34

from 1964 to 1980 ther growth of the bulge was like no other volcano. lots of tremors. planes and roadbloacks were put into place, but many tourists came to the area.

Question 35

what happened to Mt St Helen?

Answer 35

it exploded sideways, with a massive landslide of half of the volcano. volcanic ash and tephra, pyroclastic flow, and avalanches of debris. destroyed everything.

Question 36

who died in Mt St Helen?

Answer 36

David Johnstone, a volcanologist.

Question 37

what happened in Alaska 1989?

Answer 37

ash in a plane.

Question 38

how many volcanoes does Alaska hold?

Answer 38

130

Question 39

what happened with Alaska 2009 volcano?

Answer 39

there was an oil pope underneath the river and area of the volcano. technologist hazard. Redoubt volcano, all airlines stopped and nearly went bankrupt. took such a long time making a deciion whether to remove stored oil or not, that it was too late and had to evacuate.

Question 40

what lesson was learned from Redoubt 2009?

Answer 40

political and economical pressures may act with or against caution of the threat. someone has to take charge and m=cakk the shots.