Term 2 - Geology Flashcards
Describe the topics detailed in this Term. (160 cards)
1
Q
Front
A
Back
2
Q
Etymology of Geology?
A
Greek:
Geo - Earth
Ology - The Study Of
Geology - The Study of the Earth
3
Q
What are the layers of the Earth?
A
The inner core, outer core, mantle, and crust.
4
Q
Characteristics of the inner core?
A
Hot - As hot as the surface of the Sun
Solid - Composed of iron and nickel
5
Q
What is the Mantle?
A
Largest layer
6
Q
Characteristics of the mantle?
A
It is hot, but not as hot as the core.
It is mostly solid and a bit liquid, Composed of various materials
7
Q
Temperature of the Crust?
A
Cool
8
Q
Characteristics of the crust?
A
Cool
Life
Solid; Composed of rocks; various materials</div>
9
Q
Characteristics of the outer core?
A
Hot, but not as hot as the inner core
Liquid - Composed of iron and nickel</div>
10
Q
What are rocks made of?
A
Minerals
11
Q
What are minerals made of?
A
Chemicals
12
Q
What is a characteristic of minerals?
A
They are the same substance throughout.
13
Q
What are crystals?
A
Minerals that had the opportunity to grow into natural shape.
14
Q
Why are there different types of rock?
A
Because of the way they are formed.
15
Q
What is Magma?
A
Deep in the ground is molten rock called magma.Sometimes, magma bursts through the surface causing volcanic eruptions.
16
Q
How do Igneous Rocks form?
A
When magma cools and solidifies.
17
Q
What is Intrusive and Extrusive Igneous Rocks?
A
Intrusive: Igneous Rocks that form through the cooling of magma above the Earth’s surface.
Extrusive Igneous Rocks that form through the cooling of magma below the Earth’s surface.
18
Q
How do Extrusive Igneous Rocks form?
A
Magma cools above surface.
19
Q
What are the crystals like in extrusive Igneous Rocks? Why?
A
Very small; may be hard to see. Also, has fine grains.
Caused by quick cooling.
20
Q
What is another characteristic of Extrusive Igneous Rocks?
A
Usually contains large spaces. Caused by gas bubbles. Makes rock look rough and bubbly.
21
Q
Examples of Extrusive Igneous Rock?
A
Basalt, Obsidian, Pumice
22
Q
How do Intrusive Igneous Rocks form?
A
When magma cools below the surface.
23
Q
What are the crystals like in Intrusive Igneous Rocks?
A
Large and interlocking
24
Q
Examples of Intrusive Igneous Rocks?
A
Granite, Durite, Diorite
25
What are some characteristics of Igneous Rocks? Why?
They are strong and hard.
Because minerals and crystals contained are hard and strong.
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What are a characteristic of Igneous Rock Crystal?
Igneous rocks contain interlocking crystals which have grown into each other and lock together and are arranged randomly.
27
What do the crystals in Igneous Rocks look like?
A jigsaw; because the crystals are grown into eachother
28
What is Erosion?
The removal of soil and rock by natural processes such as water flow or wind.
29
What is Weathering?
The deterioration of rocks, soils, and minerals through water, atmospheric gases (wind), and sunlight.
30
What is Sediment?
Material that is broke down by the processes of weathering and erosion.
31
What is Deposition?
Process in which material is laid down or dropped to add to a landform or land mass.
32
What does Erosion to Igneous rocks?
They turn to Sediment.
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What does Deposition do to Sediment?
It turns to sedimentary rock.
34
What does erosion to the sedimentary rocks?
It turns to Sediment.
35
What does Heat and Pressure do to Sedimentary Rocks?
They turn to metamorphic rock.
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What does erosion do to Metamorphic rock?
They turn to Sediment.
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What does Melting do to Metamorphic rock?
They turn to Magma and Lava.
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What does Melting do to Sedimentary rock?
They turn to Lava and Magma.
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What does Melting do to Igneous Rocks?
They turn to Magma and Lava.
40
What does the Solidifcation of Volcanic Activity do to Magma and Lava?
They turn to Igneous Rocks.
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What does Heat and Pressure do to Igneous rocks?
They turn to Metamorphic rocks.
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What are Sedimentary rocks?
Rocks made of sediments.
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What are the three types of Sedimentary Rock?
Clastic, Organic, Chemical
44
What determines the type of Sedimentary Rock?
The way they are formed;
Formed from weathered rock fragments = Clastic
Formed from materials crystallising from solutions = Chemical
Formed from dead animal and plant material = Organic
45
What is the process of Clastic Sedimentary Rock Formation in Long Form?
Weathering creates small rock fragments which are deposited (sink) in the sea and form a sediment, building up over time.
Dead plants and animals can become trapped within the sediment forming fossils.
Over time, the pressure of layers above compact the sediment together
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What can be found in Clastic Sedimentary Rocks?
Fossils, formed by dead plant and animals that were trapped in the sediment.
47
What causes Compaction in Clastic Sedimentary Rocks?
Upper layers pushing down the the lower ones.
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What are all Clastic Sedimentary Rocks? What is their difference?
Sands, grains, and shales.
Difference is in the size of the grains.
49
What are some examples of Clastic Sedimentary Rocks?
Sandstone, shale, breccia, conglomerate
50
What is the Clastic Sedimentary Rock Formation process in steps?
1. Weathering and Erosion
2. Transportation
3. Deposition of eroded materials begin sedimentation
4. Burial, compaction, lithification
51
What is Lithification?
The process of expelling fluids, compaction, and cementation.
52
What are the characteristics of Clastic Sedimentary Rocks?
Layered,
Not interlocked grains due to cementation
May contain fossils
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How are Chemical Sedimentary rocks formed?
When materials dissolved in a solution come out of the solution, forms a solid, and sinks.
Involves evaporation and crystallisation.
54
What is the process of Halite Rock formation?
1. Crystals in water settle to the bottom; Sedimentation
2. Crystals grow as water evaporates; Evaporation
3. Water is gone and crystals cement into Halite Rock
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What are examples of Chemical Sedimentary Rocks?
Halite, limestone, gypsum
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What are the characteristics of Chemical Sedimentary Rocks?
Most have crystals
Quite soft; distinguishes from hard igneous rocks
No layering
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How are Organic Sedimentary Rock formed?
1. Dead plant and animal debris is buried under dirt or water
2. Is exposed to High pressures and heat, turning the remain sto Organic Sedimentary Rocks.
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What are examples of Organic Sedimentary rocks?
Coal, chalk
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What are the characteristics of Organic Sedimentary Rocks?
Can be layered
Mostly soft
May contain fossils
60
What are the time frames in Geology?
Paleozoic
Proterozoic
Archeozoic
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What is Paleozoic?
225 - 570 myo
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What is Proterozoic?
570 to 1000 myo
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What is Archeozoic?
More than 1500 myo
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What is a principle of rock age?
Deeper you go, older the rocks are
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How does Metamorphic Rock form?
When existing rock is changed by by high temperatures and pressures, leading to physical and chemical changes.
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What can Metamorphic Rock form from?
Igneous, Sedimentary, and other Metamorphic rocks.
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What are the different types of Metamorphism?
Contact and Regional
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What is Regional Metamorphism?
Tectonic plates moving and colliding on eachother, producing heat and compression of rock.
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What is Contact Metamorphism?
Rocks coming into contact with Magma (heat) as it pushes through the crust (pressure), causing them to change.
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What are some examples of Metamorphic Rock?
Marble
Gneiss
Schist
Slate
Phyllite
Quartzite
71
What are is an example of an Igneous Rock forming Metamorphic Rock?
Granite forming Gneiss.
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What are some examples of Sedimentary Rock forming Metamorphic Rock?
Limestone forming Marble.
Shale forming Slate.
Sandstone forming Quartzite.
73
What are some characteristics of Metamorphic Rock?
They are sometimes brightly colored.
May contain precious minerals (diamond, ruby, sapphire).
When formed from Great Pressure, may contain bands or flat, leaf-like layers, such as in Gneiss. Sometimes, they may also be zig-zaggy or wavy. Some don't have any bands.
Often has regular layers of crystal caused by Heat and Pressure.
Usually denser and harder than Sedimentary Rocks.
74
What is the structure of Earth's crust?
Made of different sections called plates.
They vary in size and move in random directions.
The crust is not smooth.
75
What causes the movement of plates?
Convection Currents
76
How do Convection Currents move the Earth? Give an analogy.
Boiling water in pan;
hot water rise, cold water sink;
cold water at the bottom heats up and then rises;
colder water at the top sinks and gets heated again;
causes a cycle of water;
Convection Currents.
77
How do Convection Currents move Plates? Do not give an analogy.
Inner mantle is heated by core;
Moves up as cold mantle sinks;
New cold mantle is heated up and rises;
New cold mantle falls and gets heated after;
Creates a cycle; Convection Currents.
78
Who and when studied plate tectonics? What were they studying specifically?
Alfred Wegener, 1910.
He was the first to study that the continents might have once been a single landmass.
He was the first to study that the continents might have once been a single landmass.
79
When was Wegener's theory accepted?
Twenty years after his death, geologists realized he was right.
80
What was Wegener's theory?
Over millions of years,
Land Masses have moved and changed.
Continents and Ocean floors "float" on moving rock plates.
Land Masses have moved and changed.
Continents and Ocean floors "float" on moving rock plates.
81
What was Wegener's evidence for his Theory?
He had convincing evidence; looked at the origins of different fossils and pieced the evidences together to form 1 landmass.
82
What were the different periods of Earth?
Permian 250 mya
Triassic 200 mya
Jurassic 145 mya
Cretaceous 65 mya
Present Day
Triassic 200 mya
Jurassic 145 mya
Cretaceous 65 mya
Present Day
83
What was the Permian Period?
One landmass: Wegener named it Pangaea
84
What was the Triassic Period?
Pangaea split into two land masses: Laurasia and Gondwanaland.
85
What was the Jurassic Period?
The continents we know today became visible.
86
How fast do Plates move?
1 - 10 centimetres a year; same speed as a fingernail growing
87
In what directions do Plates move in relation to eachother?
Close, away, or rub against.
88
What are Plate Boundaries?
Where two different plates meet.
89
What occurs in Plate Boundaries?
Lots of processes, some of which are dangerous.
90
What are Divergent Plate Boundaries? Where do they usually occur?
When two plates move apart.
Usually in the Ocean.
Usually in the Ocean.
91
What is the Process of Divergent Plate Boundaries?
Molten Rock, magma, rises up in gap between plates.
Creates shield volcanoes.
Sometimes Lava reaching above ocean = Large Eruption.
Lava cools into an island. Iceland e.g.
Creates shield volcanoes.
Sometimes Lava reaching above ocean = Large Eruption.
Lava cools into an island. Iceland e.g.
92
What happens with Divergent Plate Boundaries on Land? Example?
A rift valley is formed.
E.g. Hell's Gate, Kenya
E.g. Hell's Gate, Kenya
93
What is a smaller effect of Divergent Plate Boundaries?
Small Earthquakes
94
What are Convergent Plate Boundaries?
When two plates move towards eachother. Is usually an ocean and continental plate.
95
What is the process of Convergent Plate Boundaries?
An Oceanic and Contintental Plate collide,
Because the ocean is denser than the continent, it is subducted into the mantle and melts.
The melted material mixes with the volatile gases, forces the magma to the surface.
Leads to the some of the most destructive eruptions.
Because the ocean is denser than the continent, it is subducted into the mantle and melts.
The melted material mixes with the volatile gases, forces the magma to the surface.
Leads to the some of the most destructive eruptions.
96
What are 2 examples of the effects of Convergent Plate Boundaries?
Mt St Helens formed from Juan de Fuca and NA plate.
Italian volcanoes formed from Eurasian and African plates.
Italian volcanoes formed from Eurasian and African plates.
97
What is another consequence of Convergent Plate Boundaries?
Deadly earthquakes
98
How do Convergent Plate Boundaries create Earthquakes?
Convection Currents move plates.
Plates move together and are jammed.
Pressure builds.
Soon a plate gives way and jolts past the other.
Built-up energy is released as seismic waves, leading to Earthquakes.
Plates move together and are jammed.
Pressure builds.
Soon a plate gives way and jolts past the other.
Built-up energy is released as seismic waves, leading to Earthquakes.
99
What are and aren't the consequences of Conservative Plate Boundaries?
Destructive Earthquakes.
Not Volcanoes.
Not Volcanoes.
100
What are Conservative Plate Boundaries? Example?
When plates slide past each other.
San Andreas Fault.
San Andreas Fault.
101
How do Conservative Boundaries form Earthquakes?
Plates get stuck,
Pressure is built.
They snap past eachother,
Energy released cause Earthquakes.
Pressure is built.
They snap past eachother,
Energy released cause Earthquakes.
102
What are Collision plate boundaries?
When two continental plates move towards eachother. They move extremely slowly, over millions of years.
103
How do Collision Plate Boundaries create Earthquakes?
Plates get caught on eachother,
Pressure is built,
Energy releases as a plate snaps past.
Pressure is built,
Energy releases as a plate snaps past.
104
What is a Geological consequence of Collision Plate Boundaries that isn't an Earthquake? Over how many years? Example?
Orogeny.
Over millions of years, the crust of the Earth is pushed upwards, forming mountain ranges.
Example: Himalayas
105
Where does Freeze-Thaw Weathering and Erosion occur?
In extreme temperatures.
106
What is the process of Freeze-Thaw?
Water goes into the cracks of the rock,
It freezes and expands in the crack, putting pressure on the rock,
In the day the ice melts, leaving behind a bigger gap,
Repeat until rock die.
107
Where does Onion Skin Weathering and Erosion occur?
In very hot areas; hot days and cold nights. E.g. Deserts.
108
How does Onion Skin Weathering and Erosion work?
Surface of the rock expands and contracts frequently due to the temperature changes,
It breaks off.
It breaks off.
109
What is Acid Rain made of?
Acidic rainwater due to carbonic acid, from dissolved carbon dioxide.
For further acidity, sulfer dioxide works as well.
110
What does Acid Rain react with?
Limestone chalk or marble.
Calcium Carbonate
Calcium Carbonate
111
What does Acid Rain do to rocks?
Breaks them down
112
What are aspects of Biological Weathering and Erosion?
Plant roots break rocks.
Animal walking breaks down rock.
Anything living really just breaks down rock.
Animal walking breaks down rock.
Anything living really just breaks down rock.
113
What are the differences between Rocks and Minerals?
Their chemical composition, Study, Colour, Shape, Nutrition, Biological Function, Fossils.
114
What is the difference between Rocks and Minerals in term of Chemical Composition?
Rock: Not definite
Mineral: Definite and inorganic
115
What is the difference between Rocks and Minerals in term of Colour
Rocks: Not the Same
Minerals: Same
116
What is the difference between Rocks and Minerals in term of Examples?
Rocks: Limestone, basalt
Minerals: Gold, silver, fluoride
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What is the difference between Rocks and Minerals in term of Fossils?
Rocks: Sometimes
Minerals: None
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What is the difference between Rocks and Minerals in term of Biology?
Rocks: Shelter and Foundation
Minerals: Bone formation, blood coagulation, muscle contraction
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What is the difference between Rocks and Minerals in term of Nutriton?
Rocks: Little to none.
Mineral: Only some for nutrition.
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What is the difference between Rocks and Minerals in term of Shape?
Rock: Not definite
Mineral: Usually have a shape
121
What is the difference between Rocks and Minerals in term of Study or Expertise?
Rocks: Petrology
Minerals: Mineralogy
122
What does movement of Tectonic plates against eachother do?
Causes the plates to fold and fault.
123
What happens when a rock is placed under stress?
It deforms and/or changes shape.
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What is Deformation?
The process by which rocks change shape when under stress.
125
What is Folding?
A process where rock layers bend under stress. Its bends are called folds.
126
What is the Scientific Assumption about Rock Laayers?
That all rock layers start out as horizontal layers deposited on top of eachother over time.
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What does Folding mean for a rock? As in, what can be inferred about the rock's past?
That deformation has happened.
128
What are the Two Types of Folding?
Synclines and Anticline.
129
What is a Syncline?
It is a type of fold.
In a syncline, the youngest layers of rock are at the core of the fold.
The rock layers are usually arched downward, like a bowl.
130
What are Anticlines?
In an anticline, the oldest layers of rock are at the core of the fold.
The rock layers are usually arched upward.
131
What is a Fault?
A fault is a fracture or crack formed when large blocks of rock break and move past eachother.
It is caused by stress leading to the breaking of a rock.
132
What are Fault Blocks?
The blocks on either side of the fault.
133
What can movement of Faults cause?
Mountains and other Landforms.
134
What are the Types of Faults?
Strike-Slip (Transform) faults,
Normal Faults,
Reverse Faults.
135
What is a Fault Plane?
Location where two fault blocks meet.
136
What is the Hanging Wall?
For any fault except a perfectly vertical fault, the block above the fault plane is called the hanging wall.
137
What is the Footwall?
For any fault except a perfectly vertical fault, the block below the fault plane is the footwall.
138
What is a Normal Fault in Brief?
Hanging wall moves Down,
Extensional Stress
Divergent Boundaries
139
What are Reverse Faults in Brief?
Hanging wall moves Up,
Compressional Stress,
Convergent Boundary.
140
What are Strike-Slip Boundaries in Brief?
Horizontal movement.
Shear Stress.
Conservative/Transform Boundary
141
What is a Strike-Slip Fault?
A fault that forms when fault blocks move past eachother horizontally.
142
What type of Energy is present in Strike-Slip Faults?
Shear Stress: Stress that pushes rocks in parallel opposite directions
143
What cause Strike-Slip Faults?
Usually transform boundaries
144
What is a Normal Fault?
A fault that is created from hanging walls moving downwards relative to the footwall.
As you'd "normally" expect it to move according to gravity.
145
What type of Energy and Boundary forms Normal Faults?
Tension: Stress that pushes or pulls
Forms from Divergent Boundaries
Forms from Divergent Boundaries
146
What is a Reverse Fault?
A fault that is created from the hanging wall moving up relative to the footwall.
147
What type of Energy and Boundary cause Reverse Fault?
Compression: Stress that squeezes or pushes
Convergent Plate Boundaries
Convergent Plate Boundaries
148
What happens when rock bends? Breaks?
When rocks bend, folds form; when rocks break, faults form.
149
What happens when a rock is subject to too much stress?
It breaks; a Fault forms.
150
What is another way of stating the process of Clastic Sedimentary Formation? It is in steps, but not as detailed.
Eroded sediments are deposited and begin sedimentation.
With time, upper layers pile up and press down the lower layers; Compaction.
Fluids are expelled.
Salt crystals glue the layers together; Cementation.
151
What is an analogy for the Earth? Why?
A hard-boiled egg:
It has a hard crust around the edge;
The yellow yolk in the centre is like the earth’s core;
The egg white is like the mantle.
152
What is Chemical Weathering and Erosion?
Acid Rain.
153
What is Physical Weathering and Erosion?
Onion-Skin (exfoliation),
Freeze-Thaw.
154
What is Deformation?
The process by which rocks change shape when under stress.
155
What is Elastic Deformation?
Deformation where rock is bent, but returns back to original shape when force is stopped; a reversible strain.
156
What is Plastic/Ductile Deformation?
Deformation where a rock is bent close to breaking and held so that, when released, the bend is kept.
It is an irreversible strain.
157
What is a Fracture Deformation?
A deformation where the rock is broken; an irreversible strain where the material is broken.
158
Elastic vs Fracture?
Elastic is more plastic, the latter is more brittle.
159
What are all the types of stress that can be applied to a rock?
Confining/Uniform, Shear, Compression, Tension
160
What is Confining/Uniform Stress?
Equal stress on all sides.
