plate tectonics Flashcards Preview

Life Science > plate tectonics > Flashcards

Flashcards in plate tectonics Deck (20)
Loading flashcards...
1
Q

Lithosphere

A

the rigid outer part of the earth, consisting of the crust and upper mantle.

2
Q

Asthenosphere

A

the upper layer of the earth’s mantle, below the lithosphere, in which there is relatively low resistance to plastic flow and convection is thought to occur.

3
Q

Mesosphere

A

the region of the earth’s atmosphere above the stratosphere and below the thermosphere, between about 30 and 50 miles in altitude

4
Q

Inner Core

A

Earth’s innermost part and according to seismological studies

5
Q

Outer Core

A

a liquid layer about 2,300 km thick and composed of iron and nickel that lies above Earth’s solid inner core and below its mantle

6
Q

Seismic Waves

A

waves of energy that travel through the Earth’s layers, and are a result of an earthquake, explosion, or a volcano that gives out low-frequency acoustic energy

7
Q

Oceanic Crust

A

the relatively thin part of the earth’s crust that underlies the ocean basins

8
Q

Continental Crust

A

the layer of igneous, sedimentary, and metamorphic rocks that forms the continents and the areas of shallow seabed close to their shores, known as continental shelves.

9
Q

Density

A

a characteristic property of a substance

10
Q

Wegener

A

a German polar researcher, geophysicist and meteorologist

11
Q

Continental Drift

A

the movement of the Earth’s continents relative to each other, thus appearing to “drift” across the ocean bed

12
Q

Convergent Boundary

A

an actively deforming region where two or more tectonic plates or fragments of the lithosphere move toward one another and collide.

13
Q

Divergent Boundary

A

a linear feature that exists between two tectonic plates that are moving away from each other.

14
Q

Transform Boundary

A

a strike-slip fault that offsets a mid-ocean ridge in opposing directions on either side of an axis of seafloor spreading.

15
Q

Sea-floor Spreading

A

a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge

16
Q

Pangaea

A

was a supercontinent that existed during the late Paleozoic and early Mesozoic eras.

17
Q

Laurasia

A

was the northernmost of two supercontinents that formed part of the Pangaea supercontinent around 300 to 200 million years ago

18
Q

Gondwana

A

is the name given to the more southerly of two supercontinents that were part of the Pangaea supercontinent that existed from approximately 300 to 180 million years ago

19
Q

Mesosaurus

A

an extinct genus of reptile from the Early Permian of southern Africa and South America

20
Q

Glossopteris

A

the largest and best-known genus of the extinct order of seed ferns