Lecture 4 - Volcano

Question 1

A conical hill or mountain built around a vent that connects with reservoirs of moltem rock below the earth surface

The window of geologist to the inner part of the earth

Answer 1

Volcano

Question 2

Molten rocks below the surface of the earth

Answer 2

magma

Question 3

magma that reaches the earths surface

Answer 3

lava

Question 4

why do volcanoes erupt?

Answer 4

due to decompression
Magma is lighter than the solid rock around it

Question 5

what are the pyroclastic debris

Answer 5

Blocks, Bomb, Pumice, Cinder, Lapilli, Ash, Dust

Question 6

Pieces with 1-4 mm in diameter

Answer 6

Dust

Question 7

Fragments consisting of sharply angular glass particles, smaller than cinder

Answer 7

Ash

Question 8

Small, Slag-like, solidified pieces of magma 0.5 to 2,5 cm across

Answer 8

cinder

Question 9

peieces 2 to 64 mm in diameter; latin for little stones

Answer 9

Lapilli

Question 10

Coarse, angular pieces of the cone or broken away from rocks that block the vent (>64 mm in diameter)

Answer 10

blocks

Question 11

rounded masses that congeal from magma as it travel through air

Answer 11

bombs

Question 12

pieces of magma up to several centimeters across that have trapped bubbles of steam of other gases as they are thrown out

Answer 12

pumice

Question 13

What are the type of volcanoes

Answer 13

cinder, composite, shield, lava

Question 14

simplest type of volcano, consist almost entirely of loose, grainy cinders and almost no lava
most have bowl-shaped crater at the summit

Answer 14

cinder volcano

Question 15

consist of layers of solid lava flows mixed with layers of san or gravel like cinder or volcanic ash, moderately steep-sided and has symmetrical cone with small cater

Answer 15

composite

Question 16

built almost entirely or fluid lava flows through slow accretion of basaltic lava

almost entirely of solidified lavas and always has a large crater at the summit

Answer 16

shield volcano

Question 17

formed by relatively small, bulbous masses of lava too viscous to flow to great distance

commonly found within the craters of on the flanks of large composite volcanoes

Answer 17

lava domes

Question 18

type of volcanic eruption

Answer 18

Hawaiian, Strombolian, Vulcanian, Krakatoan, Pelean, Phreatic

Question 19

may occur along fissures of fractures of crustal blocks that serves as linear vents or at central vent

Answer 19

hawaiian

Question 20

ash is scarce and most ejecta are party fluid upon landing, fragmental ejecta, likebombs and scoria, normally precede discharge of lava

Answer 20

hawaiian

Question 21

quiet involving basaltic or andesitic magma of moderate fluidity

explosive discharge includes incandescent scroia bomb and vitric ash

Answer 21

strombolian

Question 22

lava fountain are small and exceptional, explosion clouds seldom reach 500 m

Answer 22

strombolian

Question 23

involves any type of magmka from basaltic to rhyolitic
eruption begins with phereatic type

Answer 23

vulcanian

Question 24

exhibited by mt mayon in its 2001 eruption

Answer 24

vulcanian

Question 25

karakotoan

Answer 25

volcano may collapse to form caldera

Question 26

also called as glowing cloud, glowing avalanches of fresh and effervescing magmas are produced

Answer 26

pelean

Question 27

explosive discharge of expanding stream resulting from ground or surface water coming into contact

Answer 27

phreatic

Question 28

swelling of the volcano

Answer 28

deformation

Question 29

what instrument use on swelling volcano

Answer 29

tiltmeter

Question 30

how many volcanoes are there in the philippines

Answer 30

300 volcanoes in 5 volcanic belts
22 active
27 potentially active
281 inactive