Lesson 1: Volcanoes

Question 1

The word volcano is derived from the word “_____,” a volcanic island in the Aeolian Islands of Italy

Answer 1

Vulcano

Question 2

Vulcano is originated from the name “_______” the God of fire in Roman mythology

Answer 2

Vulcan

Question 3

This type of volcano can produce violent, life threatening eruptions

Answer 3

Andesitic Types

Question 4

a bowl-shaped depression

Answer 4

crater

Question 5

connected to the magma chamber by the ______

Answer 5

vent

Question 6

these are usually less than 1km in diameter

Answer 6

crater

Question 7

these are much larger than the crater, they can reach up to 50 km in diameter

Answer 7

Calderas

Question 8

these are formed when the summit of the side of the volcano collapses onto the magma chamber

Answer 8

Calderas

Question 9

when calderas are formed, the collapsed walls of volcanoes form _____ that can stand several meters above the surface of water

Answer 9

cliffs

Question 10

a vent or “chimney” that connects molten rock (magma) from within the earth’s crust to the earth’s surface

Answer 10

volcano

Question 11

how are volcanoes formed?

Answer 11

When plates collide and one of them goes under the other, Plate collisions cause rocks to melt due to mantle heat, forming magma. High pressure and high temperature cause magma to break into the surface.

Question 12

magma release into the surface is now called ____

Answer 12

lava

Question 13

it is the most striking part of the volcano, usually composed of lava and pyroclastic

Answer 13

cone

Question 14

viscous and slow-moving grantic magma forms ________

Answer 14

high-sided steep cones

Question 15

fast-moving basaltic magma creates ________

Answer 15

low to almost flat cones

Question 16

the opening through which an eruption takes place

Answer 16

vent

Question 17

this main part of a volcano supplies the magma from the underlying source to the top of the volcano.

Answer 17

vent

Question 18

they can be straight or curvatured

Answer 18

vent

Question 19

the large underground pool of liquid rock found beneath the earth’s crust

Answer 19

magma chamber

Question 20

a basin-like depression over a vent at the summit of the cone

Answer 20

crater

Question 21

the rock or magma expelled from a volcano

Answer 21

lava

Question 22

lava temperature upon ejection can reach up to ______°C hence it flows until it cools and hardens

Answer 22

700°C

Question 23

the barrier or obstacles in a volcano

Answer 23

dikes

Question 24

otherwise known as intrusive sheets; they solidify lava flows that originally forced their way between and parallel to older later of rocks

Answer 24

sills

Question 25

a channel or pipe conveying liquid materials such as magma

Answer 25

conduit

Question 26

the side of a volcani

Answer 26

flank

Question 27

the highest point or apex of a volcano

Answer 27

summit

Question 28

the entrance of a volcano

Answer 28

throat

Question 29

expelled in the atmosphere; composed of pulverized rock and glass created during eruption

Answer 29

ash cloud

Question 30

the chuck of lava blasted into the air which solidify before reaching the ground

Answer 30

volcanic bombs

Question 31

fast-moving currents of hot gases and rock travelling downhill from a volcano

Answer 31

pyroclastic flow

Question 32

refers to fragmented material that consists of pumice, scoria, lithic materials, or crystal or combination of the four

Answer 32

tephra fall

Question 33

also called mudflows; they are flowing mixtures of volcanic debris and water

Answer 33

lahar

Question 34

they are classified as primary hot when associated with volcanic eruption, or as cold ____ when they are caused by heavy rainfall

Answer 34

lahar

Question 35

what are the diff. pyroclastic materials

Answer 35

• volcanic ashes • lapillus • volcanic blocks • volcanic bombs • lahar

Question 36

very fine, grained fragment of pulverized rock, minerals and volcanic glass

Answer 36

volcanic ashes

Question 37

made up of molten or semi molten lava, which falls on earth while still partially molten

Answer 37

lapillus

Question 38

ejected from explosive volcanic eruptions and may consist of broken pieces of the volcano's edifice

Answer 38

volcanic blocks

Question 39

how and why do volcanoes erupt?

Answer 39

Hot, molten rock (magma) is buoyant (has a lower density than the surrounding rocks) and will rise up through the crust to erupt on the surface. Same principle as hot air rising, e.g. how a hot air balloon works

Question 40

what are the three products from an explosive eruption

Answer 40

• ash fall • pyroclastic flow • pyroclastic surge

Question 41

Erupt 10's-1000's km³ of magma Send ash clouds >25 km into the stratosphere Have severe environmental and climatic effects Hazardous!!!

Answer 41

explosive eruptions

Question 42

what are the three types of volcanoes according to their activity

Answer 42

active inactive extinct

Question 43

those that have erupted over the last 10,000 years and still continue to erupt

Answer 43

active volcanoes

Question 44

those that do not erupt as of today but have a potential to do so

Answer 44

inactive volcanoes

Question 45

those that have not shown signs of activity for a long period of time. it has no record of volcanic eruptions in the past thousand years

Answer 45

extinct volcanoes

Question 46

what are the diff. typed of volcanic eruption

Answer 46

• explosive or violent eruptions • quiet or non- explosive eruption

Question 47

lava ejected is torn into shreds, forming pieces of pyroclastic materials called tephra.

Answer 47

explosive or violent eruptions

Question 48

can eject a large amount of materials into the air.

Answer 48

explosive or violent eruptions

Question 49

basaltic magma has relatively low silica content. It is less viscous and gases can escape readily from it

Answer 49

quiet or non- explosive eruption

Question 50

has wide base with gentle sloping sides. the cone is made up purely of lava that has poured out and solidified during a mild or quiet eruption.

Answer 50

shield volcano

Question 51

is built almost entirely of loose fragments called cinders (pyroclast and tephra. formed by explosive eruptions eject lava and rocks into the air.

Answer 51

cinder cone volcano

Question 52

composed of alternating layers of the lava and cinders (pyroclast). they are formed when volcanic eruptions vary between quiet and violent or explosive.

Answer 52

composite volcano / stratovolcano