Chapter 2 Section 1-2 Vocab

Question 1

Asthenosphere

Answer 1

The lower part of the Earth’s mantle that can flow very slowly.

Question 2

Continental Crust

Answer 2

Earth’s crust that underlies the continents and is composed of relatively less dense silicate minerals rich in silica and aluminum. The continental crust exceeds a thickness of 50 km in some mountain ranges.

Question 3

Convergent plate boundary

Answer 3

A region where two (or more) lithospheric plates move toward one another and collide.

Question 4

Core

Answer 4

The central part of Earth; it is divisible into an outer core that may be liquid and an inner core that may be solid.

Question 5

Crust

Answer 5

The thin, solid, outermost layer of Earth.

Question 6

Divergent plate boundary

Answer 6

A region where lithospheric plates are moving away from each other.

Question 7

Earthquake

Answer 7

A sudden notion or shaking in Earth, caused by the abrupt release of slowly accumulated strain.

Question 8

Earthquake (seismic) wave

Answer 8

A general term got all elastic waves in Earth produced by earthquakes or generated artificially by explosions.

Question 9

Epicenter

Answer 9

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

Question 10

Focus (plural: foci)

Answer 10

The point of an earthquake within Earth where rupture first occurs to cause an earthquake.

Question 11

Geologist

Answer 11

A scientist who studies the materials, processes, and history of Earth.

Question 12

Geoscientist

Answer 12

A scientist who studies the physical properties of the geosphere, atmosphere, hydrosphere, cryosphere, and biosphere on Earth and other planets.

Question 13

Global positioning system (GPS)

Answer 13

A satellite-based system scale that moves air thousands of kilometers.

Question 14

Hot spot

Answer 14

A fixed source of abundant rising magma that forms a volcanic center that has persisted for tens of millions of years.

Question 15

Lava

Answer 15

Fluid rock that comes of a volcano; magma that reaches the Earth’s surface.

Question 16

Lithosphere

Answer 16

Earth’s crust and the uppermost part of the mantle.

Question 17

Lithospheric plate

Answer 17

A rigid, thin segment of the outermost layer of Earth, consisting of Earth’s crust and part of the upper mantle. The plate can be assumed to move horizontally and adjoins other plates.

Question 18

Magma

Answer 18

Naturally occurring molten rock material generated within Earth.

Question 19

Mantle

Answer 19

The zone of Earth below the crust and above the core. It is divided into the upper mantle and lower mantle with a transition zone between them.

Question 20

Mid-ocean ridge

Answer 20

A continuous mountain range extending through the North and South Atlantic Oceans, the Indian Ocean, and the South Pacific Ocean.

Question 21

Oceanic crust

Answer 21

Earth’s crust that underlies the ocean floor and is composed of relatively dense silicate minerals rich in iron and magnesium. Oceanic crust achieves a thickness of 10-16 km.

Question 22

Plate tectonics

Answer 22

A theory in which the lithosphere is divided into a number of plates that move relative to one another.

Question 23

Rift valley (give both definitions)

Answer 23

The deep central cleft in the crest of the mid-ocean ridge; a large, long valley on a continent, formed where the continent is pulled apart by forces produced when mantle material rises up beneath the continent.

Question 24

Seamount

Answer 24

An elevation of the seafloor, 100m or higher, either flat topped or peaked.

Question 25

Transform boundary

Answer 25

A region where lithospheric plates are moving horizontally in relation to one another.

Question 26

Volcano

Answer 26

A vent in the surface of Earth through which magma and associated gases and ash erupt.