Schusterguide - Ch04 - Oceanic Geography And The Earth

Front 1

layer of the atmosphere where weather phenomena occur

Back 1

troposphere

Front 2

layer of the atmosphere that contains the ozone layer, which shields the Earth from ultraviolet radiation

Back 2

stratosphere

Front 3

composition of the early atmosphere

Back 3

hydrogen, helium

Front 4

top 4 constituents of the dry atmosphere; percentages

Back 4

nitrogen (78%), oxygen (21%), argon (0.93%), carbon dioxide (0.03%)

Front 5

all living organisms on Earth

Back 5

biosphere

Front 6

what percentage of the Earth do the oceans cover

Back 6

70.80%

Front 7

what percentage of Earth's water is held in the oceans

Back 7

97.20%

Front 8

what percentage of Earth's water is held in ice caps and glaciers

Back 8

2.15%

Front 9

what percentage of surface freshwater is held in the Great Lakes

Back 9

22%

Front 10

how long ago did the oceans form

Back 10

4 billion years ago

Front 11

where did the water in the oceans come from

Back 11

outgassing from mantle

Front 12

why is it unlikely that Earth's oceans came from ice on comets

Back 12

different isotopes of hydrogen

Front 13

4 oceans from largest to smallest area

Back 13

Pacific, Atlantic, Indian, Arctic

Front 14

average overall ocean depth

Back 14

3729 m

Front 15

4 oceans from deepest to shallowest

Back 15

Pacific, Atlantic, Indian, Arctic

Front 16

2 factors that cause eustatic (global) sea level change

Back 16

thermal expansion, melting ice caps and glaciers

Front 17

compositional layers of Earth

Back 17

crust, mantle, core

Front 18

most common mineral in the crust

Back 18

quartz (SiO2)

Front 19

what is oceanic crust's: rock composition; average thickness; density

Back 19

basalt; 8 km; 3 g/mL

Front 20

what is continental crust's: rock composition; average thickness; density

Back 20

granite; 35 km; 2.7 g/mL

Front 21

boundary between crust and mantle where seismic waves experience drastic changes in velocity

Back 21

the Moho (Mohorovicic discontinuity)

Front 22

2 most common elements in the crust

Back 22

silicon, oxygen

Front 23

composition of mantle

Back 23

iron and magnesium silicates

Front 24

composition of core

Back 24

iron, nickel

Front 25

earth's 5 mechanical layers from the surface

Back 25

lithosphere, asthenosphere, mesosphere, outer core, inner core

Front 26

how thick is the lithosphere

Back 26

~100 km

Front 27

highly viscous, but ductile layer that the lithosphere floats on

Back 27

asthenosphere

Front 28

solid mechanical layers of the Earth

Back 28

inner core, mesosphere, lithosphere

Front 29

the only liquid mechanical layer of the Earth

Back 29

outer core

Front 30

mapping and charting the sea floor by measuring its depth

Back 30

bathymetry

Front 31

measuring depth

Back 31

sounding

Front 32

early way of finding depth

Back 32

dropping piano wire with a weight

Front 33

device that sends a ping (sound), which bounces off the bottom, then detects the ping and measures the elapsed time in order to measure depth

Back 33

echo sounder

Front 34

example of a multibeam echo sounder

Back 34

Seabeam

Front 35

what is the widest swath that side-scan sonar can map

Back 35

60 km

Front 36

2 examples of side-scan sonar systems

Back 36

GLORIA, SeaMARC

Front 37

how does a satellite altimeter obtain bathymetric data

Back 37

calculates gravitational anomalies

Front 38

section of continent that includes the shelf, slope, and rise

Back 38

continental margin

Front 39

what percentage of the oceans' area do continental shelves take up

Back 39

8%

Front 40

average width of the continental shelf

Back 40

70 km

Front 41

edge of the continental shelf; average depth

Back 41

shelf break; 135 m

Front 42

which US coast has a steeper continental slope

Back 42

Pacific coast

Front 43

area of sediments deposited by turbidity currents at the bottom of the continental slope

Back 43

continental rise

Front 44

steep-sided valley engraved in the continental slope caused by erosion from turbidity currents

Back 44

submarine canyon

Front 45

what land-based feature yields a submarine canyon

Back 45

sediment-carrying river

Front 46

rapid movement of sediment-laden water down the continental slope spurred by an earthquake

Back 46

turbidity current

Front 47

layer of turbidites at the continental rise with successive layers containing large grains on the bottom and small grains on top

Back 47

graded bedding

Front 48

strong current flowing at the base of the continental slope along the western boundary of the Atlantic Ocean that helps shape continental rises

Back 48

western boundary undercurrent (WBUC)

Front 49

deep, flat area that accounts for most of ocean’s floor

Back 49

abyssal plain

Front 50

deposition of sediments from the water column that results in flatness on abyssal plains over millions of years

Back 50

suspension settling

Front 51

fan-shaped accumulation of sediment from turbidity currents that is deposited at the base of a submarine canyon

Back 51

submarine/deep-sea/abyssal fan

Front 52

largest submarine fan found in the Bay of Bengal, east of India

Back 52

Ganges fan

Front 53

one of the largest abyssal fans that reaches 700 km from the coast of South America

Back 53

Amazon cone

Front 54

times in Earth's history when the ocean might have been completely frozen at the surface 580-750 million years ago

Back 54

snowball events

Front 55

when did the last ice age end; was the sea level lower or higher during the ice age

Back 55

10,000 years ago; lower sea level during ice ages

Front 56

epoch of the last ice age; current epoch

Back 56

Pleistocene epoch; Holocene epoch

Front 57

Earth's age

Back 57

4.6 billion years

Front 58

Earth's circumference

Back 58

40,000 km

Front 59

graph of elevation versus the area of land above that elevation

Back 59

hypsographic curve