Plate tectonics

Question 1

Crust

Answer 1

upper most layer of earth–conatians the oceqanic and continetal crust and lithosphere

Question 2

Mantle

Answer 2

layer benath the crust where magma flows–contains the asthenosphere

Question 3

core

Answer 3

most inner layer of earth– contains the inner and outter core

Question 4

what are the 3 main layers of earth

Answer 4

the crust mantle and core

Question 5

oceanic crust

Answer 5

made of igneous rock, baasalt and gabbro–apart of the earths crust

Question 6

continental crust

Answer 6

made of granite rock called granodirate– apart of earths crust

Question 7

lithosphere

Answer 7

earths outer most layer that consists of the crust and uper most mantle
it forms a relatively cool and rigid slab of rock known as a plate

Question 8

asthenosphere

Answer 8

the soft and weak layer beneath the lithosphere where magma flows

Question 9

why does magma flow in the asthenosphere

Answer 9

it is close to it’s melting point so the magma becomes easily deformed

Question 10

inner core

Answer 10

made of mostly iron-nickel

Question 11

why is the inner core solid?

Answer 11

because it is compressed by immense pressure

Question 12

outer core

Answer 12

made of mostly metallic iron

Question 13

conevection

Answer 13

movement in general of either magma or just currents in general

Question 14

plates/ plate tectonics

Answer 14

huge slabs of rigid rock that are made of crust and upper most mantel which together are called the lithosphere– the magma in the asthenosphere causes the plates to move//tectonics–moving

Question 15

pangaea

Answer 15

the super continent that is thought to have existed before the continents drifted apart

Question 16

convergent boundaries

Answer 16

—-> <—– plates moving together

Question 17

divergent boundaires

Answer 17

plates moving apart (land fills the gaps and will create new land, mountians or volcanoes)

Question 18

Transform boundaries

Answer 18

—–>
<——
plates moving past one another (tension while rubbing that is realeaased causes earth quakes)

Question 19

subduction zones(happens btwn contiental and oceanic crusts collide)

Answer 19

when 2 oceanic plates are moving apart and beneath the north american plate generates water rich magma that fuels explosive eruptions

Question 20

hotspot

Answer 20

place in the upper mantle of the earth at which hot magma from the lower mantle upwells to melt through the crust

Question 21

Paleomagnetism

Answer 21

the difference of the way the north points in rocks–it switches every 300,00 years(magnetic convectios) shows us how earths magnetism is actually changing and how our earths plates have constantly been moving

Question 22

Describe the theory of Continental Drift and the person who developed this theory.

Answer 22

alfred wegner

it is believed that the continents have drifted (plates) throughout millions of years

Question 23

What is the evidence to support the theory of Continental Drift?

Answer 23

contients looked like jigsaw puzzles

rock and animal fossils in diff continents across the ocean

Question 24

What happens when two plates of continental crust collide?

Answer 24

forms a mountain range–ex himalayas – when the plates start to collide pressure builds up and they push up against and create mountians

Question 25

What happens when two plates of oceanic crust collide?

Answer 25

it is a subduction again... a trench forms and you get a volcanic island chain

Question 26

What happens when one plate of oceanic crust collides with a plate of continental crust?

Answer 26

forms a subduction zone--ex south american andes--some volcanoes form

Question 27

What forms at a divergent boundary on oceanic crust?

Answer 27

mantle rocks beneath plates are hot and as they expand and igneous rocks bulge upward they fill the sea floor expanding it and it cools and solidifies

Question 28

What forms at a divergent boundary on continental crust?

Answer 28

it forms a riff valley and eventually water will start to fill it and a linear sea will form (ex. red sea)

Question 29

Although these can occur at any plate boundary, what phenomenon is most commonly connected to transform boundaries?

Answer 29

earthquakes as the plates pass there is tension and the earthquake is the tension being released

Question 30

What is the composition of the core? How do we know this?****

Answer 30

its solid and we know because we use seismic waves to determine it( also emense pressure is being distributed to the center)

Question 31

seismic waves

Answer 31

Seismic waves are waves of energy that can be caused by earthquakes.

Question 32

Which layers are fluid? Which are solid?

Answer 32

solid: crust, upper mantle, inner core fluid: outer core, lower mantle, asthenosphere

Question 33

Why is ocean crust thinner and denser than continental crust?

Answer 33

Because of the pressure of the water in the ocean crust that compacts it

Question 34

plates

Answer 34

large slabs of rock

Question 35

what is convection

Answer 35

he movement caused within a fluid by the tendency of hotter and therefore less dense material to rise, and colder, denser material to sink under the influence of gravity, which consequently results in transfer of heat.

Question 36

where does heat originate

Answer 36

the core

Question 37

why do plates move

Answer 37

because they are onto of the asthenosphere which is very hot and easily deformed which enables to the plates to move onto of the magma

Question 38

who proved the theory of the sea floor spreading

Answer 38

Henry hess

Question 39

Which boundary runs across California?

Answer 39

san Andreas fault

Question 40

Where is nyc on the plate map? Is it on a boundary?

Answer 40

no its in the middle of one-- na plate

Question 41

At which type of boundary is crust being destroyed

Answer 41

convergent

Question 42

At which type of boundary is crust being created

Answer 42

divergent

Question 43

Trench

Answer 43

a long narrow ditch formed by a convergent boundary between a continental and a oceanic