glossary

Question 1

Asthenosphere

Answer 1

The part of the mantle, below the lithosphere, where the rock is semimolten.

Question 2

Benioff zone

Answer 2

The area where friction is created between colliding tectonic plates,
resulting in intermediate and deep earthquakes.

Question 3

Epicentre

Answer 3

The point on the Earth’s surface directly above the focus of an
earthquake.

Question 4

focal depth

Answer 4

The point on the Earth’s surface directly above the focus of an
earthquake.

Question 5

Focus

Answer 5

The point inside the Earth’s crust from which the pressure is released
when an earthquake occurs.

Question 6

Hot spot

Answer 6

Points within the middle of a tectonic plate where plumes of hot
magma rise and erupt.

Question 7

Lahar

Answer 7

A mixture of meltwater from snow and ice on top of an active
volcano and tephra (volcanic material such as ash) from eruptions
that travels very quickly down existing river valleys, reaching some
distance away from the volcano.

Question 8

Liquefaction

Answer 8

When the violent shaking during an earthquake causes surface rocks
to lose strength and become more liquid than solid.

Question 9

Lithosphere

Answer 9

The solid layer, made from the crust and upper mantle, from which
tectonic plates are formed.

Question 10

Jökulhlaup

Answer 10

intense floods of water from glacial lakes or lakes that are situated near a glacier. One possible source for this sudden activity is the eruption of a volcano under a glacier.

Question 11

tephra

Answer 11

all pieces of all fragments of rock ejected into the air by an erupting volcano.