the point beneath the earth's surface where rock breaks and causes an earthquake

• focus

• epicenter

• vent

• squall line

the point on the earth's surface directly above the focus

• epicenter

• Fujita scale

• focus

• pipe

type of seismic wave that compresses and expands

• p wave

• s wave

• surface wave

• sound wave

a type of seismic wave that moves side to side and up and down

• s wave

• p wave

• surface wave

• sound wave

the opening in a volcano through which lava and gases escape

• vent

• pipe

• crater

• epicenter

a gently sloping mountain made of lava released from nonexplosive eruptions

• shield volcano

• cinder cone

• composite volcano

• volcano

a steeply sloped volcano made of pyroclastic material from explosive eruptions

• cinder cone

• cone

• shield volcano

• composite

a tall, cone shaped, mountain made of alternating layers of lava and pyroclastic material

• composite volcano

• cinder cone

• shield volcano

• crater

a row of severe thunderstorms

• squall line

• tornado

• hurricane

• focus

a rapidly rotating column of air that extends from a cumulonimbus cloud and touches the ground

• tornado

• hurriane

• vent

• Fujita Scale