Plate Tectonics

Question 1

Lithosphere

Answer 1

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

Question 2

Asthenosphere

Answer 2

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

Question 3

Mesosphere

Answer 3

strong lower part of the mantle between the asthenosphere and the outer core

Question 4

Inner Core

Answer 4

a solid sphere in the middle of the fluid core such as the iron-nickel core of the Earth.

Question 5

Outer Core

Answer 5

The outer core of the Earth is a fluid layer about 2,300 km (1,400 mi) thick and composed of mostly iron and nickel that lies above Earth’s solid inner core and below its mantle. Its outer boundary lies 2,890 km (1,800 mi) beneath Earth’s surface.

Question 6

Seismic Waves

Answer 6

a wave of energy that travels through the Earth and away from an earthquake in all directions

Question 7

Oceanic Crust

Answer 7

the relatively thin part of the earth’s crust that underlies the ocean basins. It is geologically young compared with the continental crust and consists of basaltic rock overlain by sediments.

Question 8

Continental Crust

Answer 8

the relatively thick part of the earth’s crust that forms the large landmasses. It is generally older and more complex than the oceanic crust.

Question 9

Density

Answer 9

the ratio of the mass of a substance to the volume of a substance

Question 10

Alfred Wegener

Answer 10

German geophysicist who proposed the theory of continental drift

Question 11

Continental Drift

Answer 11

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

Question 12

Convergent Boundary

Answer 12

the boundary formed by the collision of two lithospheric plates

Question 13

Divergent Boundary

Answer 13

the boundary between two tectonic plates that are moving away from eachother

Question 14

Transform Boundary

Answer 14

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

Question 15

Sea-floor Spreading

Answer 15

the process by which new oceanic lithosphere forms as magma rises toward the surface solidifies

Question 16

Pangaea

Answer 16

hypothetical super continent that included all current land masses, believed to have been in existence before the continents broke apart during the Triassic and Jurassic Periods.

Question 17

Laurasia

Answer 17

The super continent of the Northern Hemisphere that, according to the theory of plate tectonics, broke up into North America, Greenland, Europe, and Asia except for the Indian subcontinent.

Question 18

Gondwana

Answer 18

A vast continental area believed to have existed in the southern hemisphere and to have resulted from the break-up of Pangaea in Mesozoic times.

Question 19

Mesosaurus

Answer 19

an extinct small aquatic reptile of the early Permian period, with an elongated body, flattened tail, and a long narrow snout with numerous needlelike teeth.

Question 20

Glossopteris

Answer 20

meaning “tongue”, because the leaves were tongue-shaped, and pteris, Greek for fern or feathery) is the largest and best-known genus of the extinct order of seed ferns known as Glossopteridales