Ch. 3 Science Explorer Inside Earth

Front 1

volcano

Back 1

a weak spot in the crust where molten malterial, or magma, come to the surface

Front 2

magma

Back 2

a molten mixture of rock-forming substances, gases, and water from the mantle

Front 3

lava

Back 3

when magma reaches the surface

Front 4

Ring of Fire

Back 4

major volcanic belt

Front 5

where do most volcanic eruptions occur?

Back 5

along diverging plate boundaries, such as the mid-ocean ridge, or in subduction zones around the edges of oceans.

Front 6

island arc

Back 6

string of islands formed by the volcanoes along a deep ocean trench

Front 7

hot spot

Back 7

area where magma from deep within the mantle melts through the crust like a blow torch

Front 8

what happens during a volcanic eruption?

Back 8

the gases dissolved in magma rush out, carrying the magma with them

Front 9

magma chamber

Back 9

the pocket beneath a volcano where magma collects

Front 10

pipe

Back 10

long tube in the ground that connects the magma chamber to the Earth's surface

Front 11

vent

Back 11

an opening where molten rock and gas leave the volcano

Front 12

lava flow

Back 12

the area covered by lava as it pours out of the vent

Front 13

crater

Back 13

bowl-shaped area that may form at the top of a volcano around the volcano's central vent

Front 14

silica

Back 14

material that is formed from the elements oxygen and silicon, is one of the most abundant materials in the EArth's crust and mantle
the more silica magma contains, the thicker it is

Front 15

what does the silica content of magma determine?

Back 15

whether the volcanic eruption is quiet or explosive

Front 16

pahoehoe

Back 16

fast-moving, hot lava
looks like a solid mass of winkles, billows, and ropelike coils
formed by quiet eruptions

Front 17

aa

Back 17

lava that is cooler and slowmoving
formed by quiet eruptions
when hardened, forms a rough surface consisting of of jagged lava chunks

Front 18

pyroclastic flow

Back 18

occurs when an explosive eruption hurls out ash, cinders, and bombs as well as gases

Front 19

active

Back 19

or live volcano is one that is erupting or that is expected to erupt in the near future

Front 20

dormant

Back 20

or sleeping volcano is expected to awakin in the near future and become active

Front 21

extinct

Back 21

or dead volcano is unlikely to erupt again

Front 22

hot spring

Back 22

forms when ground water heated by a nearby body of magma rises to the surface and collects in a natural pool

Front 23

pahoehoe

Back 23

fast-moving, hot lava
looks like a solid mass of winkles, billows, and ropelike coils
formed by quiet eruptions

Front 24

geyser

Back 24

a fountain of water and steam that erupts from the ground

Front 25

geothermal energy

Back 25

energy from water or steam that has been hated by magma

Front 26

shield volcanoes

Back 26

a wide, gently sloping mountain made of layers of lava and formed by quiet eruptions

Front 27

cinder cone volcano

Back 27

a steep, cone-shaped hill or mountain made of volcanic ash, cinders, and bombs piled up around a volcanoes opening

Front 28

composite volcano

Back 28

a tall, cone-shaped mountain in which layers of lava alternate with layers of ask and other volcanic materials

Front 29

caldera

Back 29

the huge hoel left by the collapse of a volcanic mountain

Front 30

volcanic neck

Back 30

forms when magma hardens in a volcano's pipe

Front 31

dike

Back 31

a slab of volcanic rock formed when magma forces itself across rock layers

Front 32

sill

Back 32

a slab of volcanic rock formed when magma squeezes between layers of rock

Front 33

batholith

Back 33

a mass of rock formed when a large body of magma cooled inside the crust

Front 34

shield volcanoes

Back 34

a wide, gently sloping mountain made of layers of lava and formed by quiet eruptions