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Flashcards in chapter 13 Deck (23):
1

Challenger Deep

deepest spot in the ocean floor

2

bathymetry

topography of the ocean floor

3

sonar

using sound energy to measure depth of sea floor

4

echo sounders

bounce a sound off an object to determine distance

5

3 major areas of the ocean floor

continental margins
deep ocean basins
oceanic ridges

6

Continental margins

outer margins of the continents and the transition to oceanic crust

7

Deep ocean basins

between the continental margins and the oceanic ridges

8

Ocean ridges

a broad, linear swell at a divergent plate boundary

9

Passive Continental Margins

Found along coastal areas that surround the Atlantic Ocean
Not associated with plate boundaries
Experience little volcanism and few earthquakes

10

Continental shelf

gently sloping, flooded portion of continent
Passive continental margin

11

Continental slope

steep structure that marks the boundary between the continental and oceanic crust
Passive continental margins

12

Continental rise

thick accumulation of sediment from the continental slope
carried by turnidity currents down sub-marine canyons
Passive continental margins

13

Active Continental Margins

where the oceanic lithosphere is being subducted beneath the continent
associated with the deep-ocean trenches
Located primarily around the Pacific Ocean

14

Deep-Ocean Trench

Long narrow creases that represent the deepest part of the seafloor
Associated with volcanic activity
Mostly found in the Pacific Ocean

15

Abyssal Plains

Flat features of the ocean floor
most level places on earth
thick accumulations of sediment
most found in atlantic ocean

16

seamounts

submarine volcanoes
some can grow into volcanic islands

17

Guyots

submerged, flat-topped seamounts

18

oceanic plateaus

vast outpourings of basaltic lavas on the ocean floor

19

Ocean ridge

longest topographic feature on Earth
Occupy elevated positions
offset by transform faults
extensive faulting and earthquakes
a rift valley exists on the axis of most ridges

20

seafloor spreading

melt escapes to sea floor and erupts as lava

21

Layers of the ocean floor

1. Deep-sea sediment
2. Basaltic pillow lavas
3. Sheeted dike complex
4. Gabbro
5. Mantle

22

black smokers

particle filled clouds that percipitate from various metals from the rock

23

continental rift

elongated depression where the lithosphere is stretched and thinned