A
What is the strength of an earthquake called?
magnitude
What type of volcano forms when alternating layers of fluid lava and tephra build up a steep mountain?
composite volcanoes
What is a volcano that has erupted recently?
active
What is the depression at the top of a volcano?
crater
What are holes or cracks that serve as escape vents for underground gases?
fumaroles
What is the trembling or shaking of the earth’s crust?
earthquake
What kind of weathering occurs when natural acids slowly eat into a rock, breaking it apart?
chemical weathering
What are scientists who study the structure of the earth called?
geologists
What kind of volcano expels hot clouds of gas and dust?
Plinian
What are the small fragments of molten rock that solidify almost instantly?
tephra
What are underwater ocean ranges called?
mid-oceanic ridges
What is directly above the focus of an earthquake?
epicenter
Does the temperature of rocks increase or decrease with depth?
Increase
What is the process that forms new soil as rocks crumble and break into smaller pieces?
weathering
What kind of volcano has lava fountains and fire curtains?
Hawaiian
What is a volcano that has been active, but has not erupted recently?
dormant
What is the study of earthquakes?
seismology
What is the point underground where an earthquake begins?
focus
What is created when trapped gases blast through the earth’s surface?
vent
What is the boundary between the earth’s crust and mantle?
Moho
What runs along the edge of the Pacific Ocean and has many volcanoes?
Ring of Fire
What is magma called when it reaches the earth’s surface?
lava
What is a volcano that has not erupted in recorded history?
extinct
What is the break in the boundary between two moving masses of rock?
fault
What allows molten rock and hot gases to escape from within the earth?
volcano
What kind of volcano forms when large amounts of fluid, runny lava gradually build up a dome-shaped mountain?
shield volcano
What can earthquakes sometimes cause?
tsunamis
What kind of volcano is formed by eruptions of mostly tephra?
cinder cone volcanoes
Name the layers of the earth starting from the outside…
crust, mantle, outer core, inner core
If the magma chamber caves in after the eruption, it forms a bowl shaped depression, called what?
calderas