Geology Midterm Flashcards
(145 cards)
1
Q
Dominant organism of Precambrian
A
Stromatolites
2
Q
Dominant Organism of Paleozoic
A
Trilobites
3
Q
Dominant Organism of Mesozoic
A
Dinosaurs
4
Q
Dominant Organism of Cenozoic
A
Humans
5
Q
The Great Dying
A
Ended Paleozic Era; Siberan Straights erupted
6
Q
Ending of Mesozoic Era
A
A Meteor hit earth
7
Q
Evidence of Ending of Mesozoic Era
A
iridium in K/T rocks; Shock Quartz; Crater
8
Q
Era
A
Due to mass extinction
9
Q
Period
A
Due to New dominant species
10
Q
Epoche
A
Due to new dominant mammal
11
Q
Rockslide
A
Fast; Sedimentary; Rock Slides down bedding plane
12
Q
Lahar
A
Fast; Volcanic ash mixed with water; Grey
13
Q
Mudflow
A
Fast; Clay mixed with water; Usually in spring due to snow melt; Very fluid
14
Q
Slump
A
Slow; Saturation of water causes soil below surface layer to drop downhill; Surface stays intact
15
Q
Creep
A
Slow; Slow movement of soil; Due to freeze/thawing; Causes tiliting of objects
16
Q
Solification
A
Slow; Top layer melts (in spring), moves slowly over permafrost; In Arctic climates
17
Q
Main cause of mass movements
A
Moisture
18
Q
Factores that affect mass movements (most important first)
A
- Amount of moisture, adds weight + makes slippery; 2. Angle of Slope; 3. Lack of vegetation; 4. Rock Type, sedimentary are more likely to slide; 5. Roundness (More round= faster)
19
Q
How to prevent mass movements
A
Fence/ walls (temperary fix); Leaving enough space; Plant vegetation; Provide good drainage (best way) (Most expensive)
20
Q
Angle of Repose
A
Max angle sediments can retain; Larger particle = large angle of repose
21
Q
Mechanical Weathering
A
Accomplished by physical forces that break down into smaller + smaller pieces without changing a rock’s mineral composition; Ex: Frost wedging, biological activity, unloading
22
Q
Chemical Weathering
A
A chemical transformation of rock into one or more new compounds
23
Q
Hydrolysis
A
Chemical Weathering; Rock reacts with acid + water to form clays
24
Q
Dissolution
A
Chemical Weathering; Carbonate (rock) and acid rain create calcium carbonate solutions; Sink holes and caves
25
Oxidation
Chemical Weathering; Rock with O2 or goundwater with Fe is a powerful agent that makes rock red
26
Weathering of granite
Hydrolysis
27
Weathering of Basalt
Oxidation
28
Weathering of Sandstone
Granual disintegration
29
Weathering of Limestone
Dissolution
30
Shale weathering
Hydolysis
31
Tropical weathering
Strong Chemical
32
Polar + Desert Weathering
Weak chemical + weak physical
33
Mid-latitude (Michigan)
Strong chemical + strong mechanical
34
How do caves form?
From dissolution
35
Usefulness of gravel
drains fast
36
Usefulness of sand
drains fast
37
Usefulness of loam
Best for plants; Lots of organics
38
Usefulness of silt
Poor aeration; Compacts easily
39
Useflness of clay
absorbs water; Doesn't let water pass through
40
How foliation forms
From pressure due to plate collisions
41
Pressure on Metamorphic rocks
Foliation
42
Increased heat on Metamorphic rocks
Larger crystals
43
Hydrothermal solution (chem. Fluids) on Metamorphic rocks
Chemical change
44
Contact metamorphism
Change due to heat; Small scale; Heat has to come in contact to change rock
45
Karat
Gold; K/24K x100= % K
46
Caret
Diamon; 1 c = 1/5 grams
47
Color of diamond
on D-Z scale; D= best color; Z+ = fancy/rare colored diamonds
48
Clarity
Loop clan; Eye clean; Slightly included
49
Loop clean
no imperfections when seen with loupe
50
Eye clean
No imperfections when seen with naked eye
51
Slightly included/included
Can see imperfections with eyes
52
Cut
One of the the 4 c's human can control; Faceting and cabochoning
53
Cabochoning
for obq gems
54
Faceting
For TPT and TLT gems
55
Round Brilliance
designed to show off diamond
56
4 C's
Cut, clarity, color, caret
57
Intrusive
Igneous rocks that form at depth
58
Extrusive
molten rock that solidifes at the surface
59
Magma
molten rock stored in Earth's crust
60
Lava
magma that reaches the surface
61
Mafic rock
low in quartz; dark in color
62
Felsic rock
high in quartz; light in color
63
Bowen's reaction series
Minerals that will cryallize at highest temp: Olivine; Minerals that will crytallize at lowest temp: quartz, mica, k-feldspar
64
Phoryritic
Igneous rock with two different sized crystals; Two distinct cooling rates
65
Phaneritic
Coarse grained; slowly cooled magma for 100's of years
66
Vesicular
Air bubbles; rapid cooling in minutes/second
67
Aphanetic
Fine grained; Rapidly cooled in days
68
Dangers of coal mining
black lung
69
Reclamation Act of 1977
A company must prove that the land can be reclaimed before mining permits are issued
70
Mining law of 1872
Authorized the propecting and mining for economic minerals; To promote development and settlement of land in the West
71
In-Situ Mining
Leaching; Solution mining that uses and acid (cyanide) to dissolve metal
72
Examles of solution mining
copper, gold, salt, nickel, uranium
73
Solution mining
uses liquid to dissolve minerals
74
Pros of Surface mining
Cheaper; Safer; Able to remove more material
75
Cons of Surface mining
Need alrge area; Hurts enviorment
76
Pros of Underground mining
Access to valuable ore; Less waste; Can dig in populated areas;; Ability to go deeper
77
Cons of Underground mining
Ventiliation issues; collapse issues; expensive
78
Halides
Halogens (Cl,F); Halite, Fluorite
79
Native Elements
On periodic table; Gold (Au) and Uranium (U)
80
Oxides
O alone; Hematite, magnetite
81
Suflides
S; Ex: FeS2; Galena, pyrite
82
Sulfates
SO4; Gypsum
83
Carbonates
COO3; Calcite, Dolomite
84
Silicates
SiO4; Most abundent mineral group
85
Feldspare
Most common
86
Diaphanetly
Amont of light that passes through mineral; TPT (Transparent), TLT (Translucent); OPQ
87
Color
Unrealiable because many minerals come in different colors
88
Streak
most useful for metallic minerals
89
Clevage
Way minerals split along planes of weakness; 1: flaky/platy; 2: stairs; 3=90: Cubes/Rectangles
90
Hardness
1-2: can scratch w/ finger nail; 3-4: Copper penny scratches mineral; 4-5: Iron nail scratches mineral; 5 and greater: Scratches glass
91
Luster
Amount of light a mineral reflects; Metallic, Nonmetallic vitreous (glass), nonmetallic earthy
92
Mineral Rules
Must be naturally occuring; Must be inorganic; Must be solid; Must have an orderly internal structure; Must have a definite chemical composition
93
Rhyolitic Lava
Thick; More explosive
94
Basaltic Lava
Thin, runny; Quiet
95
Hot spot
Shield volcano
96
Divergent
fissure
97
continent/continent
cinder
98
Ocean/continent
composite
99
Shield volcano eruption type
runny lava; quiet
100
Shield volcano cone shape
wide and big; genlty slopes
101
Products of shield volcanos
Pahohoe + Aa; Pele's hair
102
Cinder eruption type
Gaseous; Erupts once
103
Cinder Cone shape
Steep, small, and made of scoria
104
Products of Cinder
Scoria and gas
105
Caldera
Strato-> massive eruption with pyroclastic flow; Basaltic-> quiet, mainly lava
106
Composite Eruption type
Explosive; Little lava, mainly pyroclasts; Thick lava; Felsic rocks
107
Composte cone shape
Large; High viscosity lava; Deep slopes; Layers of pyroclastic +lava
108
Products of composite
pyroclasts; thick lava; pumic, rhyolite; ash
109
4 ways sediments turn into sedimentary rock
Compaction; Cementation; Precipitation;Evaportation
110
Transgression
Sea level rises; Finining upward; 1. Limestone, 2. Shale, 3. Sandstone
111
Regression
Sea level drops; Coarsing upward; 1. Sandstone, 2. Shale, 3. Limestone
112
Varves
Dark layers (fine material) (winter) + light layers (coarse material) (Summer); 1 set= 1 year; Usually sandstone
113
Gradded bedding
Large particles settle out first; High energy to low energy enviroment; deep water
114
Cross bedding
result of wind or water currents changing direction
115
Assymetrical ripple marks
Shallow water or wind; Indicated currents direction
116
Symmetrical Ripple marks
Deep water with no current
117
Ripple marks
Hard to preserve; Sand + sandstone
118
Mud Cracks
Form in alternating wet/dry enviroments; Areas called Tidal flats; Sandstone +Shale
119
Parent rock of slate
Shale
120
Parent rock of phyllite
Slate
121
Parent rock of schist
phyllite
122
Parent rock of gneiss
Schist or granite
123
Parent rock of jaspillite
Iron formation
124
Parent rock of quartzite
Sandstone
125
Parent rock of Marble
Limestone or dolomite
126
Parent rock of hornfels
basalt or scoria
127
Parent rock of anthractite
coal
128
Parent rock of metaconlomerate
conglomerate
129
Increasing metamorphism (Lowest pressure to highest)
Slate-Phyllite-Schist-Gneiss-Jaspillite
130
Low degree of metamorphism
Chlorite Muscovite and biotite
131
High Degree of Metamorphism
Stilimanite
132
Low viscosity
Runny lava
133
high viscosity
Thick lava
134
Calculate mass of ore from a pit
Volume (LWH) x % x Density = mT
135
1 caret=
.2 grams
136
Rate of plate movement
Distance/ difference in age
137
Plates move...
Towards the smallest island (oldest)
138
Silicate minerals are so common because...
Si + O2 are common elements; Difficult to weather away
139
What color is a D diamond
Colorless
140
What color is a G diamond
Light yellow
141
VS
Referring to clarity; Very slighly included
142
Volcano high in silica
Composite
143
A silica poor, iron rich, fine grained volcanic rock
basalt
144
What lithification process creates sandstone?
Cementation
145
What lithification process creates limestone?
Precipitation
