bullshit 1 Flashcards
(200 cards)
1
Q
21,000 years ago the world was ___% of ice
A
30%
2
Q
now the world is ___% of ice
A
10%
3
Q
__% of world’s freshwater is stored in antarctic / Greenland ice caps.
A
75%
4
Q
area where a glacier forms
A
zone of accumulation
5
Q
area where there is a net loss of glaciers due to melting
A
zone of ablation
6
Q
pressure of ice causes bottom to melt which lubricates it. Like ice skates on ice - whole glacier moves relative to ground
A
basal slip
7
Q
head of a glacial valley, with nearly vertical upper walls and a flat or hollowed out base
A
cirque
8
Q
sharp jagged crests along an eroded divide
A
aretes
9
Q
U shaped valley occupied by an arm of the sea
A
fjord
10
Q
all sediments of glacial origin
A
drift
11
Q
material that is deposited directly by ice
A
till
12
Q
sediment deposited by meltwater
A
stratified tilt
13
Q
till is usually ______ and poorly _____
A
unstratified and poorly sorted
14
Q
layers or ridges of till
A
morraines
15
Q
types of till
A
lateral, medial, end, ground
16
Q
examples of glacial Lorraine deposits
A
nantucket, Martha’s Vineyard, long island
17
Q
examples of depositional features from glacier deposits
A
outwash plain, kettles, drumlins, eskers, varves
18
Q
when do drumlins, eskers, and kettle lakes form?
A
after complete deglaciation
19
Q
migration of plants / animals
rebounding upward of crust
wordlwide change in sea level
climatic changes
A
indirect effects of ice age glaciers
20
Q
Variations in earth’s orbit were declared in
A
milankovitch hypothesis
21
Q
what did the milankovitch hypothesis state
A
shape (eccentricity) of earth's orbit varies angle of earth's axis (obliquity) changes axis wobbles (precession)
22
Q
successful theory for glaciations must account for
A
cooling of earth and short-term climatic changes
23
Q
proposed possible causes of glaciations
A
plate tectonics - continents arranged differently
changes in ocean circulation
milankovic cycles
24
Q
sea levels only rise if
A
melting ice is on land
25
factors that affect wind / wave development
wind strength
wind duration
fetch
26
what must the wind strength be for the energy transfer to continue
winds must be moving faster than the wave crests
27
do winds that blow for a short time generate large waves?
no
28
the uninterrupted distance over which the wind blows without changing direction
fetch
29
how to describe a wave
wave hight, wave length, and period for successive waves.
30
velocity of a wave
wavelength / period
31
what happens when a wave approaches the shore
wave speed decreases, wave length decreases, wave heigh increases, wave breaks
32
currents that are parallel to the shore
longshore currents
33
currents that are perpendicular to the shore
rip currents
34
caused by wave impact and pressure
| breaks down rock material and supplies sand to beaches
wave erosion
35
height of tides are affected by
earth-moon-sun alignment, shoreline configuration, tidal surge with storms
36
____ of waves stay approximately aligned with moons
bulging
37
examples of erosional coastal forms
sea cliffs and wave-cut terraces
38
what is the effect on beaches due to sea-level change due to warming/melting of ice caps and expansion of water in oceans
net erosion and loss of the beach
39
uplift of land or a drop in sea level
emergent coast
40
examples of an emergent coast
wave-cut cliffs / marine terraces
41
land adjured to sea subsides / sea level rises
submergent coasts
42
drowned river mouths
estuaries
43
submergent coasts have
highly irregular shorelines
44
why are coastlines different
tidal waves, wave heights, tectonics, coastal currents
45
study of ocean floor contours
bathymetry
46
how did bathymetry initially start off
heavy weight on end of rope
47
advances in bathymetry include
echo sounding
multi beam system
satellite altimetry
48
speed of sound in water
1500 m/sec
49
measured depth is less than
actual depth
50
multi beam systems essentially
mow the lawn
51
disadvantage with multi-beam systems
only 200 of them, would take around 125 years
52
what is used now for bathymetry
topex / poseidon
53
advantage of topex/ Poseidon
underwater features create gravitations pull on seawater and induce variation in sea surface height
54
3 major topographic units on the ocean floor
continental margins
ocean basin floors
mid-ocean ridge
55
passive congenital margins tend to have ___ continental shelf regions
big
56
marks the seaward edge of the continental shelf
contiental slope
57
the continental slope has a relative ___ structure
steep
58
found in regions where trenches are absent
continental rise
59
the continental slope merges into a more gradual incline which is
the continental rise
60
at the base of the continental slope, there are _____ ___ that follow submarine canyons that deposits sediment that forms deep sea fans
turbidity currents
61
extends from shoreline to shelf break
continental shelf
62
wide gently sloping (1:1000)
continental shelf
63
extends from break to rise
continental slope
64
relatively steep (1:40) (unstable)
continental slope
65
extends from slope to abyssal plain
continental rise
66
intermediate (1:100 to 1:700)
continental rise
67
deep, steep-sided valleys cut into the continental slope
submarine canyons
68
down slope movements of dense, sediment-laden water
turbidity currents
69
formed by erosion from turbidity currents
submarine canyons
70
continental slope descends abruptly into a deep ocean trench
| located primarily in pacific ocean
active continental margin
71
what makes up half the earth's surface
deep ocean basins
72
long, relatively narrow features
deepest parts of the ocean
associated with volcanic activity
deep ocean trenches
73
interconnected ridge system that is the longest topographic features on earth's surface
mid-ocean ridges
74
takes up 23% of earth's surface
mid-ocean ridges
75
thin sediment of mountainous chain of young, basaltic rock at an active ,spreading center of an ocean
mid-ocean ridges
76
along axis of some mid-ocean ridges are deep, normal fault structures called
rift valleys
77
flat, featureless expanses of sediment floor found between margins / ridges
abyssal plains
78
small, extinct volcanoes or rock intrusions near ocean ridges
abyssal hills
79
volcanic projections from ocean floor that are not above sea level
seamounts
80
chains of volcanic islands and seamounts found parallel to edges of ocean trenches
island arcs
81
found on ocean floor at mid-ocean ridges
pillow basalts
82
sites where superheated water containing dissolved minerals and gasses escape through fissure or vents
hydrothermal vents
83
range around 350 degrees C
play important role in chemical composition of seawater
discovered in 1977
very little dissolved magnesium is found in vents
hydrothermal vents
84
seawater contains high concentrations of ______
magnesium
85
as seawater circulates through _____, magnesium is removed
basalt layers
86
circular, coral islands in the middle of the ocean
atolls
87
deep sea sediment's 2 main sources
external - terrigeneous (land)
| internal - biogenic (formed by organisms)
88
economic value of ocean sediments
oil / fossil fuels, salt, and phosphorous deposits
89
determine shape / structure of the bottom of the ocean and shows chronological history
ocean sediment
90
5 categories for sediment
```
terrigeneous (land)
biogenic (organisms)
authigenic (precipitates formed in place)
volcanogenic (from volcanoes)
cosmogenic (from space)
```
91
factors that control sedimentation
particle size and depositional environment
92
strongly reflect their source and are transported to the sea by wind, rivers, and glaciers
terrigeneous sediments
93
average grain size of sediment in the ocean is equivalent to
energy of depositional environment
94
most important biogenic sediments
silica (opal) and calcium carbonate
95
silica occurs in areas of abundant ___
diatoms
96
foraminifera (calcite) is less ___
soluble
97
pteropods (aragonite) is more ___
soluble
98
dissolution is highest in ___ waters
deep
99
dissolution is highest in deep waters because
high pressure, low temperatures, low PH (high CO2)
100
"new" deep waters have ____ CO2 concentrations
low
101
"Old" deep waters have ____ CO2 concentrations
high
102
pacific deep waters are ___ than Atlantic deep waters
older
103
abundant in pacific / south Atlantic oceans
authigenic deposits
104
distribution of sediments in deep ocean depends on
latitude
distance from land masses
CCD
105
in mid 1600s, concluded Earth was only a few thousand years old
James Ussher
106
Created theory of the earth in late 1700s
James hutton
107
the theory of the earth stated what
recognized catastrophes are apart of thes law
| style of geologic processes have changed
108
fundamental principle of geology "the present is the key to the past"
uniformitarianism
109
determining when a geologic age formed relative to other geologic features
relative age
110
determining when a geologic event occurred in exact units of time
radiometric ( absolute ) age
111
oldest rocks on the bottom
law of superposition
112
sediment is deposited horizontally
principle of original horizontality
113
younger feature cuts through an older feature
principle of cross-cutting relationships
114
rocks being "baked" are ___
older
115
rocks containing another rock is
younger
116
dikes cut through ____ rocks
older
117
break in rock record
| indicate a gap in time
unconformity
118
missing time between horizontal sedimentary layer
disconformity
119
missing time between two sets of strata that are not parallel to each other
angular unconformity
120
unconformity between igneous or metamorphic rocks and younger sedimentary rock
nonconformity
121
spontaneous breaking apart (decay) of atomic nuclei
radioactivity
122
measures the amount of parent and daughter material is a
mass spectrometer
123
how to calculate age for radioactivity stuff
#of half - lives elapsed(half-life of system)
124
half-life of 5730 years
used to date very recent events
produced in upper atmosphere
carbon - 14 dating
125
greatest expanse of time
eons
126
4 eons
phanerozoic
proterozoic
archean
hadeon
127
divisions of time
eon --> era --> period --> epoch
128
eras of the Phanerozoic eon
Cenozoic ~ recent life
mesozoic ~ middle life
Paleozoic ~ ancient life
129
Urey miller experiment proved that amino acids can be produced how?
abiotically
130
origin of ocean
water vapor condensed to form clouds and rain water that formed the oceans
131
fossilized layered mounds
stromatolites
132
Precambrian history composes how much of earth's history
90%
133
the Precambrian history is divided into the __ and __ eons
Archean and Proterozoic eons
134
during this time, much of the continental crust was formed into cartons (larger blocks)
precambrian history
135
might have proceeded pangea
rodinia
136
this eon encompasses 542 million years
Phanerozoic hisotry
137
this era was dominated by Pangea assembly
Paleozoic era
138
what was before pangea
gondwana
139
marked first appearance of life forms with hard parts
| mainly restricted to the sea
paleozoic era
140
insects / plants moved to land
| first amphibians
paleozoic era
141
much of the land is above sea level
sea invades western NA
pangea begins to break, west-ward moving NA plate overrides pacific plate
mesozoic era
142
aga of dinosaures happened when
mesozoic era
143
gymnosperms and dominant trees formed
reptiles were dominant land animals
during when did this happen?
mesozoic era
144
Cretaceous - tertiary (KT) boundary (K-Pg)
extintction event at end of mesozoic era
145
age of flowering plants (angio sperms)
Cenozoic era
146
```
unsaturated zone (weathered bedrock)
pore spaces in the material are filled mainly with air
```
zone of aeration (vados zone)
147
porous bedrock (sandstone)
all pore spaces in material are filled with water
water within the pores is ground water
zone of saturation (phreatic zone)
148
the upper limit of the zone of saturation
water table
149
an impermeable layer of material (acquiclude)
aquitard
150
a permeable layer of material
aquifer
151
un-cemented, well-sorted, fractured -
more porous
152
the way for space is connected
tortuosity
153
large connected pore spaces =
high permeability
154
small, disconnected pore spaces =
low permeability
155
permeability depends on
grain size and packing
156
____ material is more permeable than fine-grained sediments
coarser
157
helps determine pore space
sorting
158
defines connectivity
grain shape
159
controls pore size
packing
160
aquifer that has an aquiclude below
unconfined
161
aquifer that has an aquiclude above and below
confined
162
an ____ aquifer can produce an artesian well
inclined
163
____ of freshwater keeps saltwater margin slightly offshore
pressure
164
how does a steep-slope affect infiltration
much run-off , poor infiltration
165
how does a gentle slope affect infiltration
little run-off, much infiltration
166
how does heavy precipitation affect inflitration
ground surface saturated, poor infiltration
167
how does vegetation affect infiltration
```
sparse = good
dense = poor
```
168
infiltration (good --> bad)
gravel, sand, clay
169
darcy's law
volume of water = cross sectional area of flow(permeable conductivity X (vertical drop / flow distance))
170
larger vertical drop =
higher flow rate
171
longer distance
= lower flow rate
172
higher permeability =
higher flow rate
173
hot springs are heated by
cooling of igneous rocks
174
formed by dissolving rock beneath earth's surface
caverns
175
caverns are formed in the zone of
saturation
176
calcite fizzes in ___ when it dissolves
acid
177
when water enters an open cavern, concentrations of dissolved CO2 in waters ___ and calcite precipitates
drop
178
cavern features are formed in the zone
of aeration
179
stalactites -
hang from ceiling
180
stalagmites
growing upward from the floor
181
land features in areas impacted by cave formation
karst topography
182
air rises at the equator due to ___ at earth's surface
heating
183
when air cools enough, water vapor in the air will
condense to form liquid rain
184
where are deserts found
near 30 N and 30 S
185
plays a role in formation of deserts
plate tectonics
climate change
human actions
186
factors in how wind carries things
wind strength
particle size
surface material
187
crescent shaped dunes, usually in groups, horns of crescents point downwards.
found with limited sand supply
concave downwards
barchans
188
reverse of butanes, slip face = convex downwind
blowout dunes
189
```
long ridges oriented at right angles to wind direction
form in arid regions
surplus of sand
absent vegetation
usually behind beaches
```
transverse dunes
190
long ridges of sand parallel to wind
can reach super high ~ 100 m
wind always in same direciton
longitudinal dunes
191
deposits of wind silt
extensive blanket deposits
primary sources are deserts / glacial stratified drift
loess
192
mounds and ridges of sand formed from the wind's bed load
sand dunes
193
the leeward slope of the dune
slip face
194
sloping layers of sand in the dune
cross beds
195
during chemical weathering in arid climates
clay forms
| thin soil forms
196
desert streams are called
wash, arroyo, wadi, donga, nullah
197
flow only during periods of rainfall
ephermal
198
desert streams are said to be
ephermal
199
large knobs of bedrock projecting from a sediment filled basin
inselbergs
200
interior drainage into basins of a desert landscape produce
alluvial fans / bajadas
| playas and playa lake
