Test 2 (Ch. 7 - 20) Flashcards
1
Q
monorovicic discontinuity
A
narrow zone of change in mineral composition at the crust
2
Q
lithosphere
A
rigid outer layer of mantle
3
Q
asthenosphere
A
easily deformed midlayer of mantle
4
Q
lower mantle
A
rigid bottom layer of mantle, rigid due to pressure
5
Q
outer core
A
liquid, generates Earth’s magnetic field
6
Q
inner core
A
solid bc of high pressure
7
Q
minerals are…
snnsa
A
solid
naturally occurring
nonliving
specific chem. composition, lil variation
atoms arranged in a pattern (crystals)
8
Q
rocks
A
made of minerals; igneous, metamorphic, sedimentary
9
Q
silicates
A
oxygen and silicon, largest group
10
Q
oxides
A
element and oxygen
11
Q
sulfides
A
elements and sulfur
12
Q
sulfates
A
element and oxygen and sulfur
13
Q
carbonates
A
element(s) and carbon and oxygen (colorless)
14
Q
halides
A
rarest (salty)
15
Q
native
A
precious metals!
16
Q
igneous rocks
A
cooling and solidifying of magma. plutonic and volcanic
17
Q
sedimentary
A
consolidation of particles, detrial and chemical/organic
18
Q
metamorphic
A
heat and pressure take action on other rocks. foliated and nonfoliated
19
Q
rock cycle
s/s/s/m/i/e/h
A
solar energy, sediments, sedimentary rocks, metamorphic rock, intrusive igneous, extrusive igneous, heat and pressure
20
Q
oceanic/continental lithosphere
A
ocean litho. is denser than continental litho.
21
Q
isostacy
A
lithosphere floats on asthenosphere, earth’s crust adjusts because of that
22
Q
topography
A
surface appearance of earth
23
Q
geomorphology
A
characteristics and development of landforms (structure, process, slope, drainage)
24
Q
internal vs. external processes
A
within earth, or from above the lithosphere
25
uniformitarianism
the present is the key to the past!
26
geologic time
age of earth and the geologic time scale
27
crust
5km-20km, the wrapping on the basketball
28
mantle
extends to 2900km, largest, three parts (litho, astheno, lower mantle), hard ice cream
29
cores
outer and inner, outer controls earth's magnetic field bc it rotates!
30
intrusive igneous
coarse grained, cools slowly below the surface and has time to crystallize
31
extrusive igneous
fine grained, cool quickly at surface and cannot see crystals with the naked eye
32
pyroclastic rock
rock that forms from material ejected from volcanos, like pumice and obsidian (froth on root beer)
33
strata
layers of the earth
34
three ways to make sedimentary rocks
1) weathering deposits bits that solidify over time
2) minerals precipitate out of solution (the ocean, limestone)
3) form from skeletons of other animals (fossils)
35
lithification
turn into stone (sedimentary)
36
sedimentary clastic rocks
fragments of preexisting rocks
37
conglomerate
pebble sized fragments in rocks
38
sedimentary chemical and organic rocks
crystal grains grow together
chemical: formed by precipitation of soluble materials and complicated chemical reaction
organic: formed by bits of dead remains
39
contact metamorphism
rock contacts magma and is rearranged
40
regional metamorphism
large volumes of rock are cooked by pressure over time
41
regional metamorphism
large volumes of rock are cooked by pressure over time
42
foliation
bonding that occurs when rocks are cooked (schist, gneiss)
43
pangea evidence (wegner)
fit of continents
glacial deposits far from poles
coal swamps/reef deposits
distribution of fossils
matching geologic units
44
midocean ridges
crust is thin or absent here, thickest at continents. this is where earthquakes occur
45
mantle convection is why the plates ________
move, lithosphere floats on asthenosphere
46
divergent boundary
plates pull away
47
convergent boundary
plates slam together
48
transform boundary
plates slide past each other
49
extrusive vs. intrusive volcanism
e: on earth's surface, basalt
i: below the surface, granite
50
high vs. low silica content
high silica: high viscosity (thick), pyroclastic, explosive eruptions
low silica: low viscosity (thin), gentle but fast eruptions
51
types of volcanoes (6)
s/c/ld/cc/c/vn
shield volcano: low silica, easily flows and grows
composite volcano: high/low silica, the movies
lava domes: masses of dormant lava that don't flow far and bulge as eruptions approach, composite
cinder cones: baby volcanoes that grow on others, composite
calderas: result from exploded volcano, crater lakes
volcanic necks: pipe of an old volcano that filled with solid lava
52
types of crustal folding (2)
a/s
anticline/upfold: A
syncline/downfold: V
53
types of crustal faulting (4)
n/r/t/ss
normal: pulled apart
reverse: compression
thrust: gently compression, up and over
strike-slip: slide past each other (streams)
54
earthquakes are caused by a sudden _______ along a ________
displacement, fault
55
weathering
small scale breakdown of material, insitchu
56
mechanical weathering
physical disintegration of rock without changes to its chemical composition
ex; salt wedging, frost wedging, temp changes, exfoliation
cool and dry climate
57
chemical weathering
decomposition of material through chemical alteration of minerals (requires moisture)
ex; oxidation
warm and humid climate
58
biotic weathering
roots, burrowing animals altering the rock structure
ex; lichens on rock
59
mass wasting
large scale movement of material. ex; talus cones on mountains!
60
slow mass wasting: creep
small, precise movements that show visual confirmation of movement.
ex; tree trunk grows out of a slope, leaning headstones and poles, cracked roads
61
fast mass wasting: fall
steep slopes, material breaks down and drops
ex; collects in talus cones
62
instant mass wasting: slide/slump
initiated by water, leaves behind scars on the land. slump is when it rotates
ex; landslide
63
fast mass wasting: flow
lots of water involved, pores in the surrounding material saturate
ex; mudflows
64
what are fluvial processes?
running water
65
overland vs. stream flow
over: unchannelled flow, high elevation
stream: channelled water movement, increases erosion
66
stream order
the first stream is the smallest, they increase in size and strength as you go up.
67
stream competence
measures the maximum PARTICLE size a stream can transport, increases with velocity
68
stream capacity
measures the amount of SOLID material a stream can transport, increases with discharge
69
stream channells (4)
s/s/m/b
1. straight channel: short, young, high geologic control
2. sinuous channel: irregular, gently curve, older
3. meandering channel: highly variable curves, older
4. braided streams: many interwoven streams, lots of sediment, glaciers
70
stream drainage patterns (2)
d/t
1. dendritic: tree pattern with random merging
2. trellis: forms in alternating soft/hard bedrock
71
downcutting
the power of moving water to lower the stream bed in search of the base level.
72
knickpoints
channel irregularities like waterfalls and rapids, knickpoint migration (niagara falls)
73
thalweg
the fastest speed in a channel, migrates as channel meanders bc of friction
74
cut bank
water moves fast on the edges of streams and cuts the bank back
75
point bar
water moves slowest on the inside curve of streams, lots of deposition occurs
76
oxbow lakes
indicator of high erosion on a floodplain, leaves a 'scar' on the land
77
delta formation (river to ocean)
slowed flow, sediment is deposited, spreads out and slows down
78
residence time
the time a water molecule is in the hydrologic cycle
79
zone of saturation vs. zone of aeration
wet layer and the semi wet or dry layer directly above it!
80
salinity ______ the density of the water
increases
81
ocean water movement (temp and density)
NH goes ____
SH goes _____
high temp = low density
high salinity = high density
high density water SINKS
NH = right
SH = left
82
spring vs. neap tides
spring: moon full/new, highest
neap: in between, 1/4 or 3/4
83
porosity and permeability
porosity: how big are the spaces?
permeability: how easily can H2O flow through?
high porosity, low permeability = styrofoam
84
lakes require: (2)
1. natural basin with restricted outlet
2. partly full
85
5% of wetlands reduces floodwater peak by ___%
50%
86
ice is _______ in erosive quality than water
stronger
87
stability (glaciers)
balance between accumulation and ablation
88
neve
what snow is compressed into in glaciers before becoming glacial ice
snowflakes, granular snow, neve, glacier ice
89
ablation zone
where glaciers are receeding. evaporation > precipiation, ice is thinning and receeding
90
accumulation zone
precipitation > evaporation, increasing glacier's flow
91
glacial flow
internal movement of a glacier, molecules. occurs in response to weight/pressure
92
glacial plucking
picking up rock material by refreezing meltwater
93
glacial abrasion
bedrock worn down by rock debris embedded in the glacier
94
triangular, rounded rocks are a sign of a ________.
if they are very rounded, it is a sign of transport by _______.
glacier
water
95
moulins
cracks in the ice in which streams run--flowing water on moving ice, melt streams
96
till
rock debris deposited by moving or melting ice
97
glaciofluvial deposition
when subglacial streams from glaciers carry sedimentary material!
98
stratified vs. unstratified
water sorts material when moving that material (stratified) OR it doesn't (unstratified)
99
continental ice sheets vs. mountain glaciers
polar latitudes vs. any latitude as long as cold
100
moraines, rumlins, kettle holes
moraines: land made of till
rumlins: low hill left behind by a glacier. steep part points to where it came from
kettle holes: left after a glacial depression
101
terminal, recissional, and ground
t: outermost limit of a glacier's advance
r: position where ice was stabilized
g: till left from under the glacier
102
pleistocene glaciation
the fancy word for the last ice age. 1/3 of the world was covered in ice. this is why we have the finger lakes
103
causes of pleistocene glaciation
atmosphere circulation
variations in solar output
variations in CO2 levels in at.
changes in continental positions
cold vs. warm climate
104
craggy peaks are a sign of a ________
glacier!
105
cirque
ice accumulation grinds at the surface of a mountain and creates this kind of a basin
106
arete vs. horn
thin razor between 2 CIRQUES
3 CIRQUE horn
107
lateral vs. medial morains
lateral: side of the glacier
medial: lateral moraine between two glaciers
108
ice in contact with water is _______ sensitive to change.
more!
109
weather vs. climate
weather: short term, local
climate: long term, regional
110
the koppen climate classification system is based on annual and monthly ________ and _________
precipitation, temperature
1st: group
2nd: precip
3rd: temp
ITCZ: A
Subrop Hi: BC
Polar Front: D
Polar Hi: E
111
A - tropical
over 64, little temp change, ITCZ
112
B - dry
30 degrees lat N and S, evap > precip, 30% of all land
113
C - mild midlat
hot summers/mild winters
114
D - severe midlat
snow in winter, mild summers, only in NH, continentality (far from oceans), Bing!
115
E - polar
below 50, 60-90 degrees lat
116
H - highlands
mountains, variable
117
boundary conditions vs. forcing agents
b: factors out of our control that determine Earth's climate
f: factors that force climate to change
118
why does climate change?
solar fluctuations via sunspots
movement of continents
milankovitch cycles (differences between earth and sun, excentricity, obliquity, precession)
ocean/atmo interactions
atmospheric changes
119
feedback mechanisms
systems in which changes in one variable create changes in another.
negative: stalls change
positive: promotes change
120
how do we know what climate was in the past?
o16/o18/ic/sc/fl/tr/ss
isotopes!
o16 vs. o18, o18 needs more energy to evap. and precip.
ice cores: o18 needs high temps, so lots of o18 = hot climate
sediment cores: analyze o in shells of animals, o18 = lots of cold climate.
fossilized leaves: serrated edges = cool climate
tree rings: wide = good conditions for growing
sedimentary structures: ex; fossilized ripples, tell us about the water level and current speed
121
younger dryas event
rapid cooling of temps likely due to mass glacial melt
122
recent evidence of climate change
m/l/h
medieval climate anomaly
little ice age
hockey stick curve: climate spikes very recently when mapped over the last 1000 years
123
the human element
mc/p/nv/m/f/sf
climate changes because humans added CO2 back into the atmosphere.
melting cryosphere
permafrost is no longer permanently frozen (positive feedback loop)
newtok village, AK is unstable
methane released from melting glacial ice
fewer cold days and more warm nights
storms and flooding are more severe
