SS Chapter 17

Question 1

Plate Tectonics

Answer 1

The theory that the earth is broken into plates and are in motion due to convection currents in the asthenosphere (upper mantle)

Question 2

Alfred Wegener

Answer 2

Proposed the continental drift theory in the 1900s

Question 3

Pangea

Answer 3

Term for the super continent which contained all the plates together

Question 4

Crust

Answer 4

The thin and solid outermost layer of the Earth above the mantle

Question 5

Lithosphere

Answer 5

The solid, outer physical layer of the Earth that consists of the the crust and the rigid upper part of the mantle

Question 6

Asthenosphere

Answer 6

The soft physical layer of the mantle on which the tectonic plates move

Question 7

Transform Boundary

Answer 7

The boundary between tectonic plates that are sliding past each other horizontally

Question 8

Continental Drift

Answer 8

The hypothesis that states that the continents once formed a single landmass, broke up, and drifted to their present locations

Question 9

Sea-floor spreading

Answer 9

The process by which new oceanic crust forms as magma rises towards the surface and solidifies at divergeny boundaries.

Question 10

Convergent Boundary

Answer 10

The boundary formed by the collision of two plates

Question 11

Divergent Boundary

Answer 11

The boundary between two tectonic plates that are moving away from each other

Question 12

Rift valley

Answer 12

Long, narrow depression formed at divergent boundaries

Question 13

Subduction

Answer 13

Process in which two plates collide and the denser ocean plate descends below the other

Question 14

Convection current

Answer 14

A current caused by the rising of heated fluid and sinking of cooled fluid believed to drive plate movement in the mantle of the earth

Question 15

Mid-ocean ridge

Answer 15

An underwater mountain range made at divergent plate boundaries

Question 16

Volcano

Answer 16

A weak spot in the crust where magma has come to the surface

Question 17

Earthquake

Answer 17

A shaking or sliding of the ground. It is caused by the sudden movement of masses of rock along a fault or by changes in the size and shape of masses of rock far beneath the earth’s surface.

Question 18

Continental crust

Answer 18

The portion of the earth’s crust that primarily contains granite, is less dense than oceanic crust, and is 20-50 km thick

Question 19

Oceanic crust

Answer 19

Thinner, more dense, younger crust making ocean floor

Question 20

Mariana Trench

Answer 20

The location of the deepest trench on earth made from two oceanic crusts converging.

Question 21

San Andreas Fault

Answer 21

A major geological fault in California formed by a sliding transform boundary.

Question 22

siesmic waves

Answer 22

vibrations that travel through Earth carrying the energy released during an earthquake

Question 23

Theory of Continental Drift

Answer 23

Idea that at one point in time all of the continents were one super continent called Pangea.

Question 24

Deep Ocean Trench

Answer 24

Extremely deep areas in the ocean that are created by a subducting plate

Question 25

Ocean basin

Answer 25

Areas that are below sea level

Question 26

Hot spot

Answer 26

An area in the mantle that is super heated and melts through the crust (like a blow-torch)

Question 27

Seismographs

Answer 27

Measures and records earthquake magnitude based on the energy released in an earthquake.

Question 28

Tsunami

Answer 28

A giant wave usually caused by an earthquake beneath the ocean floor.

Question 29

Epicenter

Answer 29

The location on the surface directly above the focus