Chapter 11: Volcanoes

Question 1

Refers to the motion of molten rocks that has reached the earth’s surface and moved down the slope of volcanic vents

Answer 1

lava/lava flow

Question 2

Difference between lava and magma?

Answer 2

location

Question 3

Where are volcanoes formed? name all 3

Answer 3

convergent plate boundaries, divergent plate boundaries, and hotspots

Question 4

What causes the tectonic plates to move?

Answer 4

convection currents

Question 5

Why are there many volcanoes along the pacific ring of fire?

Answer 5

moving of tectonic plates

Question 6

What are active volcanoes?

Answer 6

exhibit volcanic activity within the last 10,000 years

Question 7

What are Dormant Volcanoes?

Answer 7

shows no historical record in the past 10,000 years however may have the potential to erupt

Question 8

They can move toward each other, drift away from each other, or override each other with the heavier tectonic plate sinking to the mantle and the lighter plate rising above it in a process called _____?

Answer 8

subduction

Question 9

semi-molten rock

Answer 9

magma

Question 10

elongated fracture or crack on earth’s crust from which lava erupts

Answer 10

fissure

Question 11

passageway through which magma travels to reach earth’s surface

Answer 11

conduit

Question 12

opening where the volcanic materials are released

Answer 12

vent

Question 13

bowl-shaped depression at the top of the volcano where the vent is located

Answer 13

crater

Question 14

sides of a volcano

Answer 14

flank

Question 15

underground compartment where the magma is stored

Answer 15

magma chamber/magma reservoir

Question 16

Formed by highly viscous or think, slow-moving lava. Also termed as composite volcano, it has steep upper slopes. They are the most dangerous type of volcano, most of them are in the pacific ring of fire.

Answer 16

stratovolcano

Question 17

Formed by loose and fluid lava that flows over each other. They are usually low and broad, resembling a warrior’s armored _____ or a gigantic blob.

Answer 17

shield volcano

Question 18

Also known as scoria cone, is formed by fluid lava that is ejected because of high pressure that builds up in the magma chamber. Volcanic eruptions are short-lived and appear like a wild fountain show.

Answer 18

cinder cone volcano

Question 19

pulverized rocks, minerals, volcanic glass

Answer 19

ash

Question 20

avalanche of hot volcanic ash

Answer 20

ash flow

Question 21

horizontal crack with solidified or cooled magma

Answer 21

sill

Question 22

vertical crack with solidified or cooled magma

Answer 22

dyke

Question 23

This is also called mudflow or flow of volcanic debris. They can be classified into two
types: primary or hot ____ associated directly with the eruption, and secondary or cold ____
flow because of heavy rainfall.

Answer 23

Lahar

Question 24

These are hot bursts of trapped gases that push their way through solid barriers and
rapidly into the atmosphere.

Answer 24

Blasts

Question 25

This refers to a mound of lava that grows inside the crater, called a cryptodome.
If it grows outside the volcano, it is called an exodome.

Answer 25

Dome growth

Question 26

This refers to glowing hot material that moves down the slope of an erupting
volcano and comes in contact with the surface.

Answer 26

Pyroclastic flow

Question 27

These are volcanic materials of gases, ash, rock fragments, and water

Answer 27

Pyroclastic surges

Question 28

These may consist of combinations of pumice, scoria (basalt), thick rock
fragments, and crystals with tephra particle sizes ranging from 2 mm in diameter (ash) to
more than 64 mm in diameter (blocks).

Answer 28

Tephra falls

Question 29

They are series of sea waves caused by the displacement of large volumes of
water because of an underwater earthquake or volcanic eruption.

Answer 29

Tsunami

Question 30

Types of eruption:
least violent type, with highly fluid or runny lava flowing out of several vents

Answer 30

Hawaiian

Question 31

Types of eruption:
Is violent. featuring continuous ejection of magma and gas. It results in the formation of volcanic bombs and cinder cones

Answer 31

Strombolian

Question 32

Types of eruption:
A thick, viscous magma flows around the vent as solid lava and dust are ejected

Answer 32

Vulcanian

Question 33

Types of eruption:
Is the most violent and explosive type of eruption. Cause by the buildup of viscous magma and dissolved gas. this type is accompanied by fast-flowing pyroclastic debris and lahars.

Answer 33

Plinian