Features Of The Ocean And Continents

Front 1

what are fold mountains?

Back 1

1000's km long belts.

range in height up to 8.8km

form at destructive boundaries due to compression.

composed of strongly folded and faulted metamorphic rocks.

shallow-focus earthquakes are common

Front 2

what is a rift valley/graben?

Back 2

a linear strip of crust that has slipped down along two inward dipping normal faults.

Front 3

what is a craton?

Back 3

an area of flat,cores of ancient continents.

composed of highly deformed rocks called gneiss

they are aseismic

Front 4

what is the continental shelf?

Back 4

formed of continental crust, and is covered in beds of clastic sediments (sand, and clay).

Front 5

what depth from 0 do the continental shelfs range too?

Back 5

200m.

Front 6

what is the continental slope?

Back 6

the steeper (4 degree) part of the continental crust extending ffrom the continental shelf.

Front 7

what depth range is the continental slope?

Back 7

at 200m and all the way down to the abyssal plane, and the depth from these two points can be 1500m-3500m.

Front 8

what are turbidity currents?

Back 8

submarine avalanches which transport sediment down the continental slope.

Front 9

what does the end of the continental slope mark?

Back 9

the start of the oceanic crust

Front 10

what is an abyssal plane?

Back 10

a 3-5km deep ocean basin.

Front 11

state 3 characteristics of the abyssal plane

Back 11

flat and underlain by oceanic crust

covered by thin beds of fine grained pelagic sediments

asesimic

Front 12

how deep, wide and long are submarine valleys?

Back 12

11km deep

150km widde

1000s km long

Front 13

what is a seamount?

Back 13

a submarine basalt volcano, rising up to 1000m off the sea floor without reaching the sea level.

Front 14

what is a guyot?

Back 14

a seamount with a flat, eroded top

Front 15

state 4 characteristics of a Mid Ocean Ridge

Back 15

rises 2-3km above the abyssal plane and are around 1000km wide

the centre contains a deep rift valley

submarine eruptions of basalt occur

occur at constructive boundaries and shallow focus earthquakes are common

Front 16

in what year did alfred Wegener propose his hypothesis of continental drift?

Back 16

1915

Front 17

a super continent was formed when? and name this continent

Back 17

250 million years ago and its called pangea

Front 18

what were the 2 split up continents called once pangea splt?

Back 18

Laurasia and gondwanaland

Front 19

state 3 reason why continents dont fit together perfectly

Back 19

erosion

sea level change

depostion of materials

Front 20

what is the name of the fossil which has been found on all southern continents?

Back 20

glossopteris `

Front 21

why can rocks provide evidence for continental drift?

Back 21

because rocks form in different climates, for example sandstone has to be formed in a hot climate where there is sand, so rocks show that the continents have moved because the rocks are no longer in climates that they can form.