Review Flashcards
(127 cards)
1
Q
Scientific Method
A
Method of procedures used in conducting experiments that consist of systematic observation, measurement, and experiment
2
Q
Steps in the Scientific Method
A
- Observation
- Hypothesis
- Theory
- Law
3
Q
Independent Variable
A
Variable that stands alone and is not changed by other variables
4
Q
Dependent Variable
A
Variable that depends on other factors that are measured
* Expected to change as a result of an experimental manipulation of the independent variables
5
Q
Big Bang Theory
A
The idea that the universe began as just a single point, then expanded and stretched to grow as large as it is right now (and it could still be stretching)
6
Q
Nebular Theory
A
The nebular theory proposes that the bodies of our solar system evolved from
an enormous rotating cloud called the solar nebula
7
Q
Planetary differentiation
A
separating of different components of
a planet due to physical or chemical behavior
8
Q
Geologic Time
A
Split into 3-4 divisions
* Eons - Hadean, Archean, Proterozoic, Phanerozoic
* Eras - Paleozoic, Mesozoic, Cenozoic separated by mass extinctions
* separated by 5 mass extinctions
* Periods - Eras are subdivided into periods
* the basic unit of the geologic time scale
* Epochs - Finer subdivisions of time are possible, periods can be subdivided into epochs
9
Q
Discuss how a geologist would use relative dating techniques
A
The earliest layers are the youngest while the deeper ones are the oldest, determine the earth’s history
10
Q
Law of Original Horizontality
A
Sediments are deposited in beds (strata) that are horizontal or nearly horizontal and parallel or nearly parallel to Earth’s surface
11
Q
Law of Original Continuity
A
trata extend laterally in all directions until they thin or (pinch out) or reach the edge of their environment of deposition
12
Q
Law of Superposition
A
In any layered sequence of rock that has not been tilted or overturned,
the youngest layer is at the top and the oldest layer is at the bottom
13
Q
Law of Inclusion
A
Any piece of rock (inclusion- rock fragment, crystal, or fossil) that has become included in another rock or body of sediment must be older than the rock or sediment into which it has been incorporated
* The surrounding body of rock is called the matrix
14
Q
Law of Cross-Cutting Relationships
A
Any feature (a dike, vein, fracture, or fault) that cuts across a rock or body of sediment must be younger than the rock or sediment that it cuts across
15
Q
Law of Fossil Assemblages
A
Similar groups of fossils indicate similar geologic ages for the rocks that
contain them
* rocks containing the same fossils are the same age
16
Q
Law of Fossil Succession
A
Organisms preserved as fossils in sedimentary rock appeared,
became extinct, and were succeeded by newer organisms over time
* Different types of fossils indicate different ages.
17
Q
Law of Unconformities
A
Surfaces called unconformities represent gaps in the geologic record that formed where ever layers were not deposited for a time or removed by erosion
* Disconformity, Angular unconformity, Nonconformity
18
Q
What are atoms?
A
particle of matter that consists of a nucleus of protons and generally neutrons, surrounded by electrons
19
Q
Nucleus
A
the positively charged central core of an atom
20
Q
Protons
A
a subatomic particle with a positive electrical charge
21
Q
Neutrons
A
asubatomicparticle of about the same mass as aprotonbut without an electric charge
22
Q
Electrons
A
a stablesubatomicparticle with a charge of negative electricity, travels around an atom
23
Q
What are ions?
A
Atoms with a charge due to the unequal numbers of electrons and protons
24
Q
What is the atomic number and mass number of an element?
A
Atomic number: The number of protons, mass number of an element is mass number = protons + neutrons
25
Difference between a parent and daughter particle
Parent: atom before any chemical change Daughter: element formed after radioactive decay
26
What is radioactive decay?
a spontaneous process in which an isotope of an atom (the parent) loses particles from its nucleus to form an isotope of a new element (the daughter)
27
What is a half-life?
the time it takes for one-half of the parent radioactive element to decay to a daughter product
28
What rocks are used for radiometric dating?
igneous rocks and minerals are best for age dating
29
Topographic Maps
Two dimensional representations of three-dimensional landscapes
viewed from above
30
Elevation is shown above sea level using
contour lines
31
Contour Interval
difference in elevation between each contour line
32
Contour Interval math
Subtract the two index contours.
800 ft - 700 ft = 100 ft
Take the difference of the index contours and divide it by the number of lines.
100 ft/5 line = 20ft
33
Index contour
Bold contour lines that have the elevation labelled
34
Relief
difference between highest and lowest elevations
Highest Elevation – Lowest Elevation
840 ft – 700 ft = 140ft
35
Gradient
the slope between any two defined points on a map.
𝑮𝒓𝒂𝒅𝒊𝒆𝒏𝒕 = 𝐶ℎ𝑎𝑛𝑔𝑒 𝑖𝑛 𝑒𝑙𝑒𝑣𝑎𝑡𝑖𝑜𝑛 / 𝐷𝑖𝑠𝑡𝑎𝑛𝑐𝑒
36
Who is Alfred Wegener and Harry Hess?
Alfred Wegener - Continental Drift Hypothesis: All continents were once joint into a single landmass that broke apart, with the various fragments (continents) moving with respect to one another. Evidence used in support of continental drift hypothesis: Fit of the continents, Fossil evidence, Rock type and structural similarities, Paleoclimatic evidence
Harry Hess - Seafloor Spreading Hypothesis: The origin of new oceanic crust occurs at spreading ridges where 2 plates move away from each other, eventually being consumed at subduction zones (A long narrow zone where one lithospheric plate descends beneath another)
37
What is continental Drift?
the movement of continents resulting from the motion of tectonic plates
38
What is seafloor spreading?
tectonic plates split apart from each other
39
What are convergent, divergent, and transform plate boundaries?
Convergent: Boundary between two plates that are moving toward each other, Divergent: Boundary between two plates that are
moving away from each other, Transform: Plates slide past one another, and no new lithosphere is created or destroyed
40
Discuss the different types of plate boundaries and the faults that are associated with them
Convergent: Reverse Faults, Divergent: Normal faults, Transform: Strike-slip faults
41
What is paleomagnetism?
When magma cools, magnetic iron-bearing minerals align themselves with Earth’s magnetic field/ study of magnetic fields recorded in rocks, sediment, or archeological materials
42
What are mantle plumes and hot spots?
Mantle plumes: A rising plume of hot mantle material
(magma) not normally associated with a plate boundary, Hot spots: A localized zone of melting below the lithosphere that overlies a mantle plume
43
What drives plate motion?
Mantle convection drives plate motion, Molten rock in Earth’s mantle is
stirred by heat trying to escape, Upwelling and cooling of magma at mid-ocean ridges push plates apart, inking slab “pulls” the rest of the plate away from the ridge
44
What two pieces of information would researchers need to have to calculate the rate of plate motion for seafloor spreading?
Distance and time
45
Math for calculating rate:
Rate = Distance / Time
Time = Distance / Rate
Distance = Rate x Time
46
Define an earthquake and the mechanism which causes them
Earthquake: The vibration of Earth, produced by the rapid release of energy and movements that produce earthquakes are usually associated with large fractures in Earth’s crust called faults (A break in a rock mass along which movement has occurred)
47
Explain how seismologists can determine the location of an epicenter of an earthquake
The epicenter of an earthquake is located using the difference in velocities of P and S waves. Three station recordings (seismograms) are needed to locate an epicenter.
48
Be able to recognize a logical pattern between plate tectonics and earthquakes
A good fit exists between the plate tectonics model and the global distribution of earthquakes. Only shallow-focus earthquakes occur along divergent and transform fault boundaries, deep focus earthquakes only occur in association with convergent plate boundaries, subduction zones, and oceanic trenches.
49
Compare and contrast surface, primary, and secondary waves
Surface, primary, and secondary waves are all seismic waves, but surface waves are its own category of seismic waves and are much more destructive while primary and secondary are body waves and travel through the earth’s interior
50
Explain Elastic Rebound Theory
the sudden release of stored strain (energy) in rocks that results in movement along a fault
51
How do we know what the interior of the Earth looks like? What allows geologists to study the interior of the Earth?
Most of our knowledge of Earth’s interior comes from the study of earthquake waves, changes in velocities at certain depths led seismologists to conclude the Earth is composed of different shells of differing composition
52
How are layers of the Earth defined?
Crust, Upper Mantel, Mantle, Outer Core, Core
53
What are the Lithosphere, Asthenosphere, Crust, Mantle, and Core?
Crust: Earth’s relatively thin, rocky outer shell,
Mantle: Solid, rocky layer, contains 82% of Earth’s volume, 2 parts: upper mantle (Litho,Astheno) and lower mantle,
Lithosphere: Rigid outer layer of the Earth that includes the crust and the upper mantle,
Asthenosphere: A subdivision of the mantle situated below the lithosphere where rocks are near their melting points and are easily deformed,
Core: The innermost layer of Earth based on composition, largely composed on iron and nickel with some other lighter elements
54
What is the Moho discontinuity?
The boundary separating the crust and the mantle, identified by an increase in seismic wave velocity
55
What type of rocks make up the continental crust and oceanic crust?
Continental crust: Granite, Oceanic crust: Basalt
56
Describe the difference between the inner and outer core
Inner core: Hot, solid inner sphere,
Outer core: Liquid outer layer, composed mostly of an iron-nickel alloy, convective flow within generates Earth’s magnetic field
57
What is geothermal gradient?
Earth’s temperature gradually increases with an increase in depth at a rate
58
What is deformation?
general term that refers to all changes in the shape, position, or orientation rock body
59
What are four characteristics of rock deformation?
Temperature, Confining pressure, Rock type, Time
60
Anticlines, Synclines, Domes, and Basins
Anticlines: a fold in which layers are older as you move from the outer part of the fold toward that axial surface,
Synclines: a fold in which layers are youngers as you move from the outer part of the fold towards the axial surface,
Domes: circular upfolded structures, Basins: Circular downfolded structure
61
What are faults?
fractures in rocks, along which movement occurs
62
Be able to identify the hanging wall and footwall
Hanging wall: rock surface above the
fault,
Footwall: rock surface below the fault
63
Normal, reverse, and dip-slip faults
Dip-slip faults: Movement is mainly parallel to the dip (downslope angle) of the fault surface,
Normal: The hanging wall moves down relative to the footwall,
Reverse: The hanging wall block moves up relative to the footwall block
64
What are joints?
Fracture in a rock along which there has been no movement
65
What are strikes and dips?
Strikes (Trend): The compass direction of the line produced by the intersection of an inclined rock layer or fault with a horizontal plane,
Dips (inclination): The angle of inclination of the surface of a rock unit or fault measured from a horizontal plane
66
The classification of dip slip faults is based on the movement of which wall?
Two types of dip-slip faults can be distinguished by the relative movement of the hanging wall and foot wall of a fault
67
What are the steps to identifying a mineral?
View the following: element or compound, orderly internal structure, characteristic chemical composition, crystal form, and physical properties like appearance color, how they break, how well they resist being scratched, how they smell, taste, and feel
68
What is a mineral?
A naturally occurring inorganic element or compound having an orderly internal structure and characteristic chemical composition, crystal form, and physical properties
69
What are atoms, ions, anions, and cations?
Atoms: particle of matter that consists of a nucleus of protons and generally neutrons, surrounded by electrons,
Ions: Atoms with a charge due to the unequal numbers of electrons and protons,
Anions: Atoms that pick up extra electrons and become negatively charged,
Cations: Atoms that give away extra electrons and become positively charged
70
Ionic, covalent, and metallic bonds
Ionic: one or more valence electron are transferred from one atom to another or simply, one atom gives up its valence electrons, and the other uses them to complete its outer shell, Covalent: the bond produced by the sharing of electrons, Metallic: electrons are free to migrate from one ion to another
71
Crystals, Crystallization, Crystal Structures
Crystals: any natural solid with an ordered, repetitive, atomic structure, Crystallization: the formation and growth of a crystalline solid from a liquid or gas, Crystal Structures: the particular repeating arrangement of atoms (molecules or ions) throughout a crystal
72
Compositions of minerals and why/how they vary
Native Elements – single elements, Silicates – Contains oxygen & silica, Carbonates – Carbon, oxygen, and a metal ion, Oxides – Metallic ion & oxygen, Sulfides – Sulfur & metallic ion
73
Physical properties of minerals
Luster, Color, Streak, Crystal Shape (habit), Tenacity, Hardness (most useful), Cleavage, Fracture, Density
74
What physical properties are not used to identify minerals
Color, very ambiguous or misleading
75
Chemical formula of quartz and calcite
Quartz: ( SiO2 ) oxygen & silica,
Calcite: ( CaCO3) Carbon, oxygen, and a metal ion
76
Optical properties of minerals
Luster, Color, Streak, Ability to transmit light
77
The 8 most abundant elements in the crust
Oxygen, Silicon, Aluminum, Iron, Calcium, Sodium, Potassium, Magnesium
78
The two major divisions in mineral classes
Silicates, Non-silicates
79
The silicon-oxygen tetrahedron
Four oxygen anions surrounding one comparatively small silicon cation, forming a tetrahedron
80
Various silicate mineral classes and types
Feldspars, Quartz, Mica, Pyroxene, Amphibole, Olivine,
ferromagnesian, Clay minerals
81
Non-silicate mineral class
The carbonates, The sulfates, The sulfides, The halides
82
Understand the generation, components, and characteristics of magma
Mixture of melted rock, crystals, and dissolved gasses beneath the surface of the Earth, Igneous rocks form as molten rock cools and solidifies Consists of three components: Liquid portion, Solids, Volatiles
83
Compare and contrast extrusive and igneous rocks
oth extrusive and igneous rocks are formed by magma as it cools down, but extrusive rock is formed on the Earth’s surface while intrusive is formed inside of the Earth
84
Discuss the relationship between cooling rate and igneous rock textures
Rate of cooling: Slow rate = fewer but larger crystals, fast rate = many small crystals, very fast rate forms glass – no visible crystals, The higher the rate of cooling the smaller the size of the crystals
85
Identify and describe textures and the specific volcanic environment they formed it
Aphanitic (fine-grained) texture
* Rapid rate of cooling
Phaneritic (coarse-grained) texture
* Slow cooling
Pyroclastic texture
* Fragmental appearance produced by violent volcanic eruptions
Porphyritic texture
* Two distinct crystal sizes
* Minerals form at different temperatures.
Glassy texture
* Very rapid cooling of lava
Pegmatitic texture
* Exceptionally coarse-grained (Largest crystal sizes)
* Form in late stages of crystallization of granitic magmas
86
Identify and describe igneous rock types and the specific volcanic environment they formed it
Felsic: forms out of the melting material beneath Earth's continental crust,
Intermediate: formed convergent plate boundaries in which an oceanic plate is subducting beneath either another oceanic plate,
Mafic: mid-ocean ridge seafloor spreading centers, Ultramafic: forms in upper mantle, Pyroclastic: forms in violent volcano eruptions,
Porphyritic: formed when magma forms slowly crystallizing within the Earth's crust is suddenly erupted at the surface which causes uncrystallized magma to cool quickly
Vesicular: magma reaching the surface as lava and cools, the rock solidifies around the gas bubbles and traps them inside, preserving them as holes filled with gas
87
Describe the Bowen’s reaction series and its relationship to crystallization of silicate minerals
describes the temperature at which minerals crystallize when cooled, or melt when heated, a single volcano may extrude lavas exhibiting very different compositions
88
Understand what each of the textures mean
The different textures are all dependent on the fact where the rock forms and how long it takes to cool
89
Identify different types of volcanoes and their features
Composite cone: Large, classic-shaped volcano, Composed of interbedded lava flows and layers of pyroclastic debris, Most Violent type of Eruption
Cinder cone: Built from ejected lava (mainly cinder-sized) fragments, Steep slope angle, rather small size
Shield volcano: Broad, slightly dome-shaped, composed primarily of basaltic lava, generally covers large areas, produced by mild eruptions of large volumes of lava
90
Understand the term viscosity and its relationship to velocity
Viscosity: a measure of a material’s resistance to flow (higher viscosity materials flow with great difficulty). The cooler the lava, the higher the viscosity.
91
Describe how viscosity controls the nature of a volcanic eruption
the viscosity of magma will determine the shape a volcano takes over continued eruptions and can block gas from escaping through vents, allowing pressure to build up inside the volcano's plumbing system
92
Describe different types of volcanic eruptions and their variations
Pyroclastic flows: Highly heated mixture of ash, lava, and pumice fragments that travel down the sides of a volcano, 2 parts: Basal flow that moves along the ground, a cloud of ash.
93
Recognize and identify intrusive and extrusive volcanic features
Intrusive: Magma, Crater: steep-walled depression at the summit, less than 1 km in diameter, Caldera: summit depression typically greater than 1 km in diameter and produced by a collapse following a massive eruption, Vent: An opening connected to the magma chamber via a pipe
Extrusive: Lava, ash and dust, pumice, volcanic gases
94
Understand the relationship between volcanic activity and plate tectonics
Most volcanoes are located within or near ocean basins (at subduction zones). Most igneous activity occurs along plate margins. Spreading centers: The greatest volume of volcanic rock is produced along the oceanic ridge system
95
List different volcanic hazards
Eruption, Earthquakes, Pyroclastic Flows, Poisonous Gases, Lahars, Mud Flows, Seiches, Fires
96
Discuss historic volcanic eruptions and the hazards associated with each
Mount St. Helens eruption: Pyroclastic Flow, Mount Vesuvius & Pompeii: Pyroclastic Eruption
97
Understand how metamorphic rocks form
transition of one rock into another by temperatures and/or pressures unlike those in which it formed
98
Define the agents of metamorphism
Heat (temperature, most important), Pressure – differential stress, Hydrothermal Fluids, Time, Protolith (parent rock)
99
Describe six environmental conditions for metamorphism
Contact or thermal metamorphism—driven by a rise in temperature within the host rock
Hydrothermal metamorphism – chemical alterations from hot, ion-rich water
Regional metamorphism – Occurs during mountain building, produces the greatest volume of metamorphic rock, rocks usually display zones of contact and/or hydrothermal metamorphism.
Impact – (meteorite strikes)
Burial – sedimentary rock that is buried deep enough to be subject to temperatures above 200ºC
Faulting – Occurs at depth and high temperatures, pre-existing minerals deform by ductile flow
100
Understand the relationship between pressure and temperature in the formation of metamorphic rocks
Temperature causes recrystallization results in new, stable minerals. Pressure affects and determines the foliation in a rock
101
Define foliated and non-foliated
Foliated: any planar arrangement of mineral grains or structural
features within a rock
Non-foliated: Metamorphic rocks that lack foliation
102
Relate high and low-grade metamorphism to formation conditions
As the intensity of metamorphism increases, so does the degree of foliation
103
Recognize textures and identify metamorphic rocks
Foliated: Slate, Phyllite, Schist, Gneiss
Non-foliated: Marble, Quartzite, Hornfels, Meta conglomerate, Anthracite Coal, Soapstone
Foliated/Nonfoliated: Eclogite, Amphibolite
104
Recognize metamorphic zones and define index minerals
Metamorphic zones: an area where, as a result of metamorphism, the same combination of minerals occur in the bedrock.
Index minerals: minerals that are good indicators of the metamorphic conditions in which they form
105
Relate metamorphism to plate tectonic processes
Most metamorphism occurs along convergent plate boundaries,
large-scale metamorphism also occurs along subduction zones at convergent boundaries, Important site of magma generation, mountainous terrains along subduction zones exhibit distinct linear belts of metamorphic rocks
106
Detrital vs Chemical Rocks
Detrital: accumulation of solid particles Chemical: made of material that was precipitated from water by inorganic or organic processes
107
What is used to distinguish between types of sedimentary rocks?
Sedimentary rock types are based on the source of the material; Sedimentary rocks are also classified by the textures present: Clastic and Nonclastic
108
What is the most common type of sedimentary rock?
Shale is the most common sedimentary rock
109
What is the most abundant type of chemical rock?
Limestone is the most abundant chemical sedimentary rock
110
How do evaporite rocks form?
Evaporite sedimentary rocks form due to the deposition of chemical precipitates
111
Is coal a sedimentary rock? Why or why not?
Having been transported and accumulated in a single deposit it is sedimentary
112
What is diagenesis?
The chemical, physical, and biological changes that take place after
sediments are deposited
113
Clastic vs. Nonclastic
Clastic: composed of broken fragments of preexisting rock
Nonclastic: pattern of interlocking mineral crystals
114
What are sedimentary environments?
Geographic setting where sediment is accumulating
115
Why are sedimentary structures important?
provide clues regarding the processes of transport and deposition in ancient rocks, and the physiochemical conditions during and shortly after sedimentation
116
Soil Science
study of soil as a natural resource on the surface of the Earth
117
What is weathering?
the physical breakdown and chemical decomposition
of rock
118
What is Mass Wasting?
the downslope movement of rock, regolith, and soil under the direct influence of gravity
119
What are mass wasting events classified based on?
Type of material involved, Type of motion, The velocity of the movement
120
What is Erosion?
the physical removal of material by water, wind, ice, or gravity to its area of deposition
121
What are the two types of weathering? What are a few examples of each?
The 2 types of weathering are mechanical (Unloading, thermal expansion) and chemical (Dissolution, Oxidation, Hydrolysis)
122
What factors affect weathering?
Surface area, Rock characteristics, Climate, Differential weathering
123
What is soil?
A combination of weathered rock and mineral fragments with organic matter, water, and air
124
What factors control soil formation?
Parent material, climate, biota (organisms), topography and time
125
The soil horizons
O horizon (organic matter), A horizon (mineral, humus), E horizon (eluviation), B horizon (clay, subsoil), C horizon (partially altered parent material), R horizon (bedrock)
126
How long does it take for soil to form?
500 to 1,000 years
127
Rock Cycle
1. Magma or Lava
2. Crystallization
3. Igneous Rocks
4. Weathering and Erosion
5. Sediments
6. Lithification
7. Sedimentary rocks
8. Metamorphism
9. Metamorphic rocks
10. (Re)melting
11. Igneous rocks --> Metamorphism --> Metamorphic rocks
12. Metamorphic rocks --> Weathering and Erosion --> Sediments
