General Geo Flashcards
1
Q
belives that the earth was created in 4004 BC and it’s landscape had been shaped primarily by great catastrophes.
A
Catastrophism
2
Q
states that physical, chemical and biological laws that operate today also operated in the geologic past
A
Uniformitarianism
3
Q
says that rocks are formed by emplacement and solidification of lava from volcanoes
A
Plutonism
4
Q
plutonism is proposed by
A
James Hutton
5
Q
concept that says rocks had settled out of a large ocean whose level gradually dropped over
A
Neptunism
6
Q
same concept as uniformitarianism but the events occur at different rate
A
Actualism
7
Q
father of stratigraphy
A
Nicholas Steno
8
Q
Beds were originally deposited nearly horizontally due to gravitational pull
A
Law of Original Horizontality
9
Q
Younger strata lie on top of the older strata
A
Law of superposition
10
Q
strata are deposited laterally until sediments supply last or encounter any geologic barrier
A
Law of lateral continuity
11
Q
laws proposed by Charles
A
Law of cross-cutting Relationship
Law of inclusion
Law of Fossil Succession
12
Q
ordering strata by examining contained fossil
A
Law of Fossil Succession
13
Q
structures that cut across strata are younger.
A
Law of cross-cutting Relationship
14
Q
rocks that have been included are relatively older than the host rock.
A
Law of inclusion
15
Q
Remains or traces of prehistoric life which were essential in the development of the geologic time scale
A
fossil
16
Q
igneous or metamorphic rock inclusions
A
xenolith
17
Q
sedimentary rock inclusions
A
Clasts
18
Q
Clasts vs Xenolith
A
19
Q
Events or strata are placed in their proper sequence or order without knowing their age
A
Relative Dating
20
Q
Produce of calculating the approximate ages of rocks and minerals containing radioactive isotopes
A
Absolute Dating
21
Q
A chart that divides the earth’s vast history (4.6 billion) into Eon, era, period and epochs that utilized the absolute and relative ages of the rocks
A
Geologic time scale
22
Q
Hydrosphere covers_______z% of the earth’s surface and has a depth if about _______
A
71%, 3800m or 12,500ft
23
Q
layer of gas that surrounds the earth is called
A
Atmosphere
24
Q
Division of the atmosphere that extends from the mean sea lvl to about 100km sea lvl, mix of atmosphere gases is roughly constant
A
Homosphere
25
Found above the homosphere where the mixture of gases changes with altitude
Heterosphere
26
Lowest and densest layer of the Earth's atmosphere
that extends from the mean sea level up to an average of 10 km above sea level, the tropopause, contains roughly about 80% of the mass of the Earth's atmosphere, and where most of weather and climate phenomena are confined.
Troposphere
27
Extends to approximately about 9 km above sea level at poles, and approximately about 17 km above sea level at the equator.
Troposphere
28
Boundary between the Troposphere and the Stratosphere
tropopause
29
The second major layer in the atmosphere that extends from the Tropopause up to about 50 km above sea level, and contains the ozone layer.
Stratosphere
30
Boundary between the Stratosphere and Mesosphere.
Stratopause
31
Part of the atmosphere that contains relatively high concentration oh ozone, which also protects the Earth from UV rays, but traps the rays that enter.
Ozone Layer
32
Penetrates glass & deep into the skin, causing skin damage and aging.
UV-A
33
Dangerous between 10:00AM to 4:00PM, with its rays able to cause skin cancer, but can be easily blocked by glass & clothes. UV-C-Deadliest of the three UV rays, but mostly absorbed by the Earth's atmosphere.
UV-B
34
The third layer of the Earth's atmosphere that extends from the Stratopause to about 85 km above sea level, with the temperature within this layer dropping with increasing altitude, having an average temperature of about -85°C.
Mesosphere
35
The boundary between the Mesosphere and Thermosphere.
Mesopause
36
also known as night clouds, these are tenuous cloud-like phenomena appearing in the Mesosphere.
Noctilucent clouds
37
The layer in the atmosphere that extends from the Mesopause to about 600 km above sea level, and is completely cloudless and water vapor free. Auroras also occur within this layer.
Thermosphere
38
A natural phenomena that are results of disturbances in the magnetosphere, caused by solar winds, and are found in high-latitude regions.
Auroras
39
A dynamic comet-shaped region around the planet created by the interaction of solar wind with Earth's magnetic field, that acts as a barrier of Earth from space weather.
Magnetosphere
40
orbits within the Thermosphere, between 350 and 420 km above sea level.
*The International Space Station (ISS)
41
The outermost layer of the Earth's atmosphere that extends up to 10,000 km above sea level, and contains most of the satellites orbiting Exobase-The boundary between the Thermosphere and Exosphere.
the planet.
Exosphere
42
The global ecological system integrating all living beings and their relationships, including their interaction with the elements of the geosphere, hydrosphere and atmosphere
Biosphere
43
Note about biosphere
*Ocean life is concentrated in the sunlit surface water of the sea. On land, most life is concentrated near the surface, with tree roots and burrowing animals reaching a few meters underground, and flying insects and birds reaching about a kilometer above land.
44
Encompasses the solid Earth that extends from the surface to the center of the planet, about 6,400 km deep.
Geosphere
45
The process of transforming original pieces of matter into an ordered, concentric layers that are separated by physical and chemical properties.
Differentiation
46
The process of gradual accumulation of additional layers of material, causing a growth or increase in body mass.
Accretion
47
MODELS FOR EARTH'S ACCRETION & DIFFERENTIATION
Homogeneous Accretion (Ringwood, 1979), Heterogeneous Accretion (Turkenia and Clark, 1969),
Magma Ocean Model
48
2-step process of Homogeneous Accretion (Ringwood, 1979)
1. Accretion of a homogenous or undifferentiated proto-Earth
2. Subsequent differentiation into a metallic core and silicate
mantle.
49
Core and mantle material simultaneously formed, but accreted and differentiated at separate times.
Heterogeneous Accretion (Turkenia and Clark, 1969)
50
The Earth experienced a large-scale melting, that may have been due to continuous collisions of planetesimals the radioactive decay of short-lived nuclides or the effects of the excess greenhouse gases, and formed one or more magma oceans during the late stage of its accretion.
Magma Ocean Model
51
LAYERS of the earth BY CHEMICAL COMPOSITION
Crust, Conrod Discontinuity, Mantle, Mohorovicic Discontinuity, Core
52
Outermost layer of the Earth by chemical composition.
Crust
53
Boundary between Upper and Lower Crust.
Conrod Discontinuity
54
A solid, rocky shell that constitutes the great bulk of the Earth, 83% by volume and 62% by mass, that extends to a depth of 2900 km deep. The uppermost part is dominantly peridotite.
Mantle
55
Boundary between Crust and Mantle. 6300km
Boundary between Crust and Mantle. 6300km
56
Central mass that's about 3,480 km in radius, making up about 16% of the Earth's volume, and composed of an iron-nickel alloy, with minor amounts of oxygen, silicon, and sulfur, with an average density of nearly 11 g/cm3 due to extreme pressure.
Core
57
Boundary between Mantle and Core.
Gutenburg Discontinuity
58
The rigid outer physical layer consisting of the entire crust and upper mantle, which rupture due to stress, producing earthquakes, and broken into large fragments called plates.
Lithosphere
59
LAYERS of the earth BY MECHANICAL/PHYSICAL PROPERTIES
Lithosphere,
Mohorovicic Discontinuity,
Low Velocity Zone, Asthenosphere,
Transition Zone,
Repiti Discontinuity, Mesosphere,
D" Layer,
Ultra-Low Velocity Zone
Gutenburg Discontinuity
Outer Core
Geodynamo
Lehmann Discontinuity
Inner Core
60
Boundary between Lithosphere and Asthenosphere.
Mohorovicic Discontinuity
61
Contact between the Lithosphere and the Asthenosphere where small amounts of partial melting occur, causing decrease in P-wave velocity.
Low Velocity Zone
62
Plastic and free-flowing enough not to rupture when subjected to stress, but have more rigid solids compared to the Low-Velocity Zone, which increases the P-wave velocity. It is dominantly composed of Olivine, Pyroxene, and Garnet.
Asthenosphere
63
Contact between the Asthenosphere and the Mesosphere, where at this layer, Olivine transforms into Wadleysite, which transforms into Ringwoodite, and together with Garnet, transforms into Perovskite and Periclase at the depth of 660 km.
Transition Zone
64
Boundary between Asthenosphere and Mesosphere.
Repiti Discontinuity
65
The lower mantle extending from 660 km to 2900 km in depth. Dominantly composed of Perovskite, Periclase, Magnesiowustite, Stishovite, Ilmenite, and Ferrite.
Mesosphere
66
Common site of anomalous seismic signals. Characterized by anomalously fast velocities that may have been caused by lithosphere subducted all the way down to the ______. It contains the Ultra-Low Velocity Zone (UVLZ) in the lowermost part.
D" Layer
67
Found in the lowermost part of the D" Layer that causes a large decrease in P-Wave velocity, and may be related to the formation of deep mantle plumes within the lower mantle.
Ultra-Low Velocity Zone
68
Boundary between Mesosphere and Outer Core.
Gutenburg Discontinuity
69
A dramatic decrease in P-Wave velocity and absence of S-Wave due to the layer being liquid. It is highly incompressible with a density of 10-12 g/cm3. The circulation of the molten iron causes geodynamo. Dominantly composed of iron and nickel alloy.
Outer Core
70
The production of most of Earth's magnetic field.
Geodynamo
71
Boundary between Outer Core and Inner Core.
Lehmann Discontinuity
72
A solid inner core that is 13 g/cm3 in density, that has a rapid increase in P-Wave velocity and reoccurrence of S-Wave velocity. It is seismically anisotropic, which makes seismic velocity travel faster in one direction compared to the rest due to the parallel alignment of iron-rich crystals. Dominantly composed of iron and nickel alloy.
Inner Core
73
earth's external structure
Continents, and Ocean basins
74
2 categories of continets
1. Extensive, flat stable areas
2. Uplifted regions
75
Typically located in the interior of the continents.
Extensive, flat stable areas
76
Long, narrow features at the margins of
continents.
Uplifted regions
77
Average elevation of the continental features
0.8km
78
Includes the region surrounding the Pacific
Ocean: the mountains of the western Americas and the island arcs in the eastern Pacific.
Circum-Pacific Belt
79
Found along the boundary of the Indian plate and Eurasian plate.
Alps and the Himalayas
80
a mountain range Found in the Eastern United States.
Appalachians
81
a mountain range in Eurasia that runs north-south mostly through Russia
Urals
82
The interiors of the continents that have been relatively stable or undisturbed for at least 600 million years.
Stable interior
83
Expansive, flat regions composed of deformed crystalline rock, or highly deformed igneous and metamorphic rocks, that is typically a basement complex.
Shields
84
Extensive, flat stable regions of the continents covered by a relatively thin veneer of sedimentary
rocks.
Stable platform/Craton
85
Portion of the seafloor adjacent to major
landmasses.
Continental Margin
86
A gently-sloping platform that extends seaward from the shore which is also considered as the flooded extension of the continents.
Continental Shelf
87
A relatively steep drop-off that extends from the outer edge of the continental shelf to the floor of the deep ocean.
Continental Slope
88
A thick accumulation of sediments that moved
downslope from the continental shelf to the deep-ocean floor.
Continental Rise
89
The Earth's surface is ___% ocean basins, and ___% continents
60, 40
90
Area between the continental margins and oceanic ridges.
Deep-Ocean Basins
91
Incredibly flat features in deep-ocean basins.
Abyssal Plains
92
Extremely deep, relatively narrow depressions that are occasionally more than 11 km deep, with some located adjacent to young mountains or volcanic island arcs.
Deep-Ocean Trenches
93
Submerged volcanic structures which sometimes form long narrow chains dotting the ocean floor.
Seamounts
94
The most prominent feature on the ocean floor. This broad elevated feature forms a continuous belt that can wind for more than 70,000 km around the globe in a manner similar to the seam of the seam of a baseball.
Oceanic Ridges
95
take note
The ocean floor also contains extremely deep depressions that are occasionally more than 11,000 m (36,000 ft.) deep.
