Chapter 2 Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

What are the sections of the earth?

A

Inner core
-Solid, mostly iron and nickel

Outer core
-Liquid, mostly iron

Mantle
-Semi solid layer of rock that helps transports portions of the overlying crust

Crust
-Solid outer layer of Earth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Is continental crust lighter than oceanic crust?

A

Yes

Continental crust typically contains a greater amount of lighter elements than oceanic crust of similar volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Does subtle difference in density influence how continental and oceanic crust of different plates interact?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the probable composition of Ocean and Continental crusts?

A

Oceanic crust probable composition is basalt
Continental Crust probable composition is granite

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are Plate tectonics?

A

the large scale motion plates of the Earth’s lithosphere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is seafloor spreading?

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is subduction?

A

takes place at convergent boundaries plates where on plate moves under another and is forced or sinks because of gravity into the mantle

Ocean crust sinks
Continental crust floats

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Are tectonic regions complex?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the three types of plate boundaries?

A

Diverging Boundaries
Converging boundaries
Transform boundaries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is Diverging Boundaries?

A

Where the plates move apart
From rift zones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are converging boundaries?

A

Where plates collide
From subduction zones, where trenches are produced, or thrusts zones, where mountains are formed

Pressure and friction from subduction melt rock which emerges as volcanoes in cracks along the edge of the oceanic crust

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is transform boundaires?

A

Where one plate slides past each other in opposite directions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Where is oceanic islands commonly formed?

A

Along subduction zones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where are hot spot volcanoes formed?

A

where plumes of superheated mantle melt through overlying plate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How are series of islands formed?

A

A series of islands may form as the plate migrates over the hot spot

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

How are mountains and islands made?

A

Plate movements can result in vulcanisms, leading to mountain formation on continental crust and island formation on oceanic crust

Hot spot volcanism is another way island can form

As oceanic crust subducts, series of islands or mountains are formed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the estimated time the Earth was formed?

A

~4.5 BY(Billion Years) ago

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the estimated time Guam was made?

A

44 MY(Million Years) ago

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Is Guam’s Geological History Complex?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the two phases of Guam’s Geo history? (Explain the phases as well)

A

Volcanic phase
-44 MY BP - 5 MY BP
-Guam and the other five southernmost islands of the Marianas are no longer volcanically active
-Primarily submarine volcanism

Carbonate Phase
-Primarily 5 MY BP to present
-Onset coincided with rifting of the Marianas from the West Mariana Ridge
-Includes “framework” and “detrital” limestone formations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is Limestone made out of?

A

Calcium carbonate, it dissolves in water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Explain the Geo Map of Guam

A

Volcanic formations primarily in S Guam

Limestone formations primarily in N Guam

Formations become exposed through tectonic uplift

Geology influences the regional soils, hydrology, and biology of Guam

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Did northern Guam use to have an atoll?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What reduced carbonate sediment?

A

Erosion and dissolution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How is an Atoll island formed?

A

from coral rubble piled up from wave activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is climate?

A

the long term pattern of factors such as temperature, rainfall, day length, and their seasonal changes

the long term atmospheric conditions for a particular area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

What is weather?

A

the shorter term variations in atmospheric factors (wind, humidity, rainfall, etc.)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Is there more rainfall in the north and the east coast?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Is there less rain in the middle and west of Guam?

A

Yes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What influences the vegetation of a particular area?

A

Temperature, water availability, and sunlight

31
Q

What do regions that have similar climatic conditions have in common?

A

They have plants with similar growth forms and physiologist (collectively called “physiognomies”)

32
Q

Different ____________ are defined by their particular climate and physiognomies

A

Biomes

33
Q

What do Tropical islands experience?

A

experience only modest seasonal variation in temp and sunlight

34
Q

What do islands have within a given year

A

seasonal variation in rainfall and wind

Rainy season
Dry season

35
Q

What do many tropical organisms exhibit?

A

seasonal variation in reproduction, recruitment and migration

36
Q

What are the 2 common perturbations the tropical pacific islands experience?

A

El nino and the southern oscillation

37
Q

What is ENSO?

A

El Nino ad Southern Oscillation

38
Q

What does El Nino mean?

A

the boy child

warm, wet years

Coasts of Peru and Chile are deserts
But some years, rains come and in summer deserts “bloom”
Summer in southern hemisphere - Christmas
Other effects: warm waters -> bad fishing

39
Q

What is the Southern Oscillation?

A

Monsoon

When air pressure high over s pacific ocean it was low over Indian ocean -> trade winds blow

When air pressure low over s pacific ocean, it was high over Indian ocean -> wind stops or reverses direction

This seesaw he called the southern oscillation

40
Q

What is an Monsoon?

A

wind that reverses direction seasonally, bring rain

India - rain in summer

Some years, monsoons don’t happen -> drought and starvation

Sir Gilbert walker investigated this

41
Q

What are the Many effects of the ENSO?

A

Fisheries fail, deserts bloom, typhoons, droughts

42
Q

What happens in the Normal years (la nina)?

A

Trade winds push warm water across pacific ( e -> w in n pacific)

usually cold, dry years

Upwelling - cold, nutrient rich water rising from ocean depths in E pacific

Feeds phytoplankton and fish!
Sea level 2 ft higher

43
Q

What happens in El Nino Years?

A

Trade winds weaken, may reverse

No upwelling -> no fish

Sea level on w pacific islands drop -> reef exposed, many die

Typhoons form farther east -> Hawaii, tahiti

44
Q

What are Iguanas?

A

marine herbivores, eat green seaweeds

45
Q

What did El nino do the the iguanas and sea lions in the galapagos?

A

Warm waters from El nino destroyed food supplies

46
Q

What are Sea Lions?

A

carnivores, eat fish

47
Q

What is a tropical depression?

A

a tropical cyclone with Maximum sustained winds of 38 mph (33 knots) or less

48
Q

what is a tropical storm?

A

a Tropical cyclone with maximum 73 mph (63 knots) and a minimum 39 mph (34 knots)

49
Q

What is a typhoon?

A

a Tropical cyclone with max, sustained winds of 74 mph (64 knots) or higher

50
Q

what is a major typhoon?

A

a Tropical cyclone With maximum sustained winds of 111 mph (96 knots) or higher, corresponding to a category 3, 4, or 5

51
Q

What does an average sized typhoon release?

A

releases 2,400 billion kilowatts (KW) of power every day

52
Q

What is the estimated amounts of tropical storms, typhoons, and super typhoons Guam recieves?

A

Tropical storm - every 1 - 2 years

Typhoon- every 4-5 years

Super Typhoon- every 50 - 60 tears

52 Tropical cyclones passed within 69 miles from 1945 - 1993

53
Q

What are the effects of Typhoon on an island’s communities?

A

Typhoons modify terrestrial Communities by increasing leaf litter and opening forest gaps

Reefs may experience damage from waves and surge

Atolls may become flooded and groundwater from the aquifer may become contaminated with salt

54
Q

Where does the Pacific Plate move to?

A

Southeast to northwest

Subducts under the Mariana Microplate

Also includes Uplift

Resulted in Guam moving eastward

55
Q

What is Oceanic-Continental Converging Boundaries?

A

More dense oceanic crust subducts under less dense continental crust when the 2 plates converge

56
Q

What is oceanic-oceanic converging boundaries?

A

Density of both crust are similar

subduction is determined by factors such as plate size and pressure and friction

Makes volcanoes

Forms trenches

57
Q

What is Continental-continental converging boundaries?

A

Both plates usually go up and form mountain ranges

58
Q

How many plates are on the Earth’s crust?

A

14 major plates

59
Q

Where was Guam Originally placed/started?

A

20 degrees south of its current location and possibly farther west along the Philippine plate

60
Q

What are the 3 volcanic formation places that dominate southern Guam?

A

Facpi
Alutom
Umatac

61
Q

What is a type I islet?

A

Grow and sink but remain about the same size and same location

Very susceptible to large storms

Is easily manipulated to ocean currents

62
Q

What is a type II islet?

A

Largest, most stable, have the best developed soil and freshwater

Tend to keep getting larger

63
Q

What is Type III islet?

A

Complex combinations of characters

not stable

mid-sized but tends to be reshaped dramatically during storms

64
Q

Does temperature on tropical islands depend mainly on altitude?

A

Yes

65
Q

What are the 2 sets of factors that shape the Pacific Island environments?

A

1) Geological nature of the island (High/low; volcanic/continents)

2) Geographic location, rainfall patterns

66
Q

What are the ocean effects during Normal and La Nina years?

A

West Pacific
-Low atmospheric pressure
-High sea level
-More rainfall

East Pacific
-High atmospheric pressure
-Low sea level
-Less rainfall

67
Q

What are the oceans effects during el nino years?

A

West pacific
-Low sea level
-drought
-high atmospheric pressure

Central pacific
-rainfall

East pacific
-high sea level
-rainfall
-low atmospheric pressure
-thermocline shuts off

68
Q

Does winds always blow from high pressure areas to low pressure areas?

A

Yes

69
Q

When easterly winds/trade winds are strong?

A

there is little/no rain

70
Q

When easterly winds/trade winds are weaken

A

heavy rain

71
Q

When the traveling winds are strong, they push water across the tropical pacific, making sea level…

A

2 feet higher in the W pacific than the E pacific

72
Q

What is the Adelup-chalan pago line?

A

A fault line

73
Q

What is the Orographic effect?

A

Elevation of high islands promotes the condensation of moisture/rainfall