Week 3 Flashcards
(99 cards)
1
Q
Density of Continental Rocks
A
2.7 g/cm^3
2
Q
Density of Oceanic Rocks
A
3.0 g/cm^3
3
Q
The volume of mantle in terms of percentage
A
82.00%
4
Q
Dominant rock of the upper mantle
A
Peridotite
5
Q
Relatively stable areas involced in orogenic episodes much earlier in the geologic time scale
A
Cratons
6
Q
expansive flat regions made up of deformed igneous and metamorphic rocks; part of a highly eroded mountain systems
A
Shields
7
Q
Flat area of a craton where highly deformed rocks are overlain by a thin veneer of sedimentary rocks.
A
Stable Platforms
8
Q
A portion of a seafloor adjacent to major landmasses
A
Continental Margins
9
Q
refers to a flat expanse on the ocean floor located at considerable depths, typically ranging from 3,000 to 6,000 meters. These plains are commonly situated between the base of a continental rise and a mid-ocean ridge, constituting over half of the Earth’s surface.
A
Abbysal Plains
10
Q
a prolonged, slender, and sharply sloped depression on the ocean floor where the greatest oceanic depths are found, ranging from approximately 7,300 to over 11,000 meters. These trenches usually develop in regions where one tectonic plate undergoes subduction beneath another.
A
Deep Ocean Trenches
11
Q
The Benioff Zone, also known as the seismic zone or seismic plane, is a tilted, planar cluster of earthquake hypocenters that reaches up to 700 km deep. In the context of plate tectonics, the Benioff Zone serves as the location where one tectonic plate is subducted beneath another and is commonly termed a subduction zone.
A
Benioff Zone
12
Q
The East African Rift is associated with what type of plate boundary
A
Divergent boundary
13
Q
The distribution of the youngest mountain are located principally in two zones
A
> Circum-Pacific Belt
An eastward trending mountain belt from the Alps, Iran, Himalayas and then extending to Indonesia
14
Q
What would be examples of older mountain belts
A
> Appalaichians, US
Urals, Russia
15
Q
Shields vs Stable Platforms
A
> Sheilds are mostly deformed igneous and metamorphic
16
Q
The continental margin are made of up three zones
A
Continental Shelf, Continental Slope, and Continental Rise
17
Q
Define the continental shelf
A
> Gently sloping platforn extending seaward from shore
A flooded extension of continents
18
Q
Define the continental slope
A
> Boundary between continents and deep-ocean basisn
Steep dropoff extending from outer edge of the continental shield to the deep ocean floor
19
Q
Define the continental rise
A
> Found in regions without trenches
a gradual incline with thick wedges of sediments
20
Q
Define deep-ocean basins
A
> large depressions or low areas on the ocean floor that are characterized by considerable depths.
21
Q
Define Volcanic Island Arcs
A
> volcanic island chains associated with subduction zones
formed from volcanic activity resulted from subduction related magma generation
22
Q
Define Mid-ocean ridge
A
> underwater mountain range that stretches across the Earth’s ocean basins
formed from divergent tectonic plates where the resulting crustal thinning encouraes mantle material to rise
23
Q
The two broad areas of Geology
A
Physical Geology and Historical Geology
24
Q
Physical vs Historical Geology
A
> Physical geology tackles the processes and phenomenon that shapes the structure, composition and, features of the Earth
Historical geology focuses on the Earth’s past and biological evolution through the geological time
25
Catastrophism vs uniformitarianism
> Catastrophism proposes that the geological features seen today are a result of sudden and violent events or catastrophies
> Uniformitarianism proposes that the geological features today are shaped by the same processes since its formation
26
Positive vs negative feedback mechanisms
> In a positive feedback mechanism, an initial change in a system triggers responses that further intensify or amplify that change
> a negative feedback mechanism works to counteract or dampen the effects of an initial change, promoting stability within a system.
27
Define Mantle Plumes
> upwellings of hot, buoyant rock from the Earth's mantle that reach the surface, creating volcanic features. These plumes are thought to originate near the core-mantle boundary and ascend through the Earth's mantle
28
Enumerate the plagiocalse mineral series
Albite, Bywotonite, Labradorite, Andesine, Oligoclase, Anorthite
29
Illustrate and describe the rock cycle
> Magma cools and solidies, then crystalizes into igneous rocks
> Rock exposed to the elements is subjected to weathering, small material produced (called sediments) are transported and deposited
>Deposited sediments lithifies and undergoes diagenesis in order to become sedimentary rocks
>Sedimentary and Igneous rocks under the right pressure-temperature conditions are altered into metamorphic rocks
>All kinds of rock, when deep enough will be subjected to very high temperatues which causes melting into magma
30
How are volcanic island arc formed and give examples
> Oceanic Plate-Oceanic Plate convergence occurs
> Older and denser plate subducts, forming a trench
> Part of the subducting slab is sbjected to increasing PT consitions, which promotes partial melting of magma
> Generated magma rises through the crust, which would eventually generate an arc of volcanic islands parallel to the generated trench
> Examples : Philippine Is., Aleutian Is., Japan
31
What would happen if two continental crust collides with each other
> No subduction occurs due to lighter density
> Crustal shortening and thickening process occurs which paves way to orogenesis
> Example: Himalayas
32
How is it that noble gases are chemically inert
> Noble gases has a complete set of valence electrons, thus making them stable and unlikey to form bonds with other molecules under normal conditios
33
Explain Ionic bonding by illustrating the chemical reaction of Na and Cl to form Halite
>Sodium donates a valence electron to chlorine
> Both elements now has a stable configuration, Na donates its single electron leavin behind a complete and stable electron shell, Cl receive the electron and completes its outer shell
34
Coal, graphite and diamond are made up of carbon atoms and yet why is it that coal is not considered as a mineral?
> Graphite and diamond are substances that are fomed by inorganic matter, whereas coal is.
35
What makes a mineral exhibit cleavage and illustrate an example
> Weaknesses in the crystal lattice causes a mineral to have cleavages
> An example would be the weak bonding between sheets seen in phyllosilicates
36
Color is typically not a powerful tool in identifying minerals. Why is that?
> A single mineral can exhibit colors and multiple different minerals can have the same color due to impurities in the lattice. Such minerals are called Allorchromatic minerals
> Quarts has many varieties based on its color. Green quartz is called adventurine, violed is amethyst, yellow is citrine, and etc.
37
Expound more on the factors that dictates the viscosity of magma
>Silica content plays a factor in magma viscosity, The more the silica content, the more it is viscous
> The amount of volatiles affect magma mobility. More volatiles would cause more fluidity and less viscosity
38
Explain the triggering factors on hawaiian-type eruptions
> involved low viscosity basaltic magma
> triggered by the arrival of new batch of melt into a magma reservior
> magma accumulates pressue which fractures the overlying rock, magma can move upward through these fractures creating outpourings for weeks to years.
39
How would density play a role in plate tectonics
> The density difference between continental and oceanic crust would allow the subduction of the latter which in turn enables forces such as slab pull to provide movement to the plates
> The density differences between lithosphere are asthenosphere allows the former to "float" over the latter and move
40
Why is the transition of calcic to sodic plagioclase in the bowens reaction series referred to as "continuous"?
> It is continuous because the mineral involved is feldspar. The differnces in the sequence is the transition from the calcic end member to the sodic end member of the mineral series.
41
a surface that connects similar points on adjacent waves.
Wave Front
42
A line constructed at right angles to the wave front is called the
Wave Normal
43
the direction of propagation of light energy.
Light Ray
44
lf two waves vibrate in the same plane and travel along the sarne path, they interfere with each other. The distance that one wave lags behind the other is calléd the
Retardation
45
optical property of a material having a refractive index that depends on the polarization and propagation direction of light
Birefringence
46
the color after red in the visible spectrum
orange
47
Olivine would belong in what crystal system
Orthorhombic
48
What would happen when the incident light reaches beyond the critical angle
Total internal reflection occurs
49
Give the chemical formula for Augite
Ca(Mg,Fe)Si206
50
Two waves are said to be in phase when
> they contrustively interfere with each other
51
Two waves are said to be out of phase when
> they destructively interfere and cancel with each other
52
Describe the tetragonal system
crystals which can be referred to three mutually perpendicular axes; the two horizontal axes are of equal length, but the vertical axis is either shorter or longer than the other two.
53
Describe the Orthorhombic system
crystals which are referred to three mutually perpendicular axes, all of different lengths.
54
What is polychromatic light
A light containing a range or spectrum of wavelengths. (Many colored)
55
What is monochromatic light
Light with a single isolated wavelength (single colored)
56
Light can travel from a higher index to a lower index regardless of the angle of incidence [T or F, correcte the erroneous statement if F]
> F
> Light travelling from a lower index to higher index can travel freely regardless of the angle of incidence
57
Define the critical angle
the angle of incidence beyond which total internal reflection occurs.
58
How would one differentiate orthopyroxene and clinopyroxen from each other when looking through cross poloried light
> Clinopyroxenes have high order interference colors with inclined extinction
> Othropyroxene have lower order greys and has parallel extinction
59
A rock sample in the field is initially identified as gabbro. What would be the expected minerals seen when analyzing the sample in thin section
> Plagioclase, Clinopyroxene and, Othopyroxene
60
Categories of igneous rocks in terms of grain size
Plutonic, Hypabyssal, and volcanic
61
Categories of igneous rocks in terms of composition
Felsic, Intermediate, Mafic, ultramafic
62
Illustrate the differences of lightrays passing through isostropic mineral and a anisotropic mineral
> wave normal and light rays are perpendicular to wave front in isotropic minerals, while light rays in anisotropic minerals are not usually parallel
63
Why is it that quartz and felspathoids are not seen together in nature.
> Feldspathoids only form when the magma is silica undersaturated
> Quartz can only form in magmas rich in silica
64
Why is it that petrographic analysis is not optimal for aphanitic rocks and what method would serve as a workaround
>It is generally difficult to find the representative mineralogical mode or an apahnitic rock due to very small grain sizes
> Geochmical analyses are utilized to classiffy and analyze such rocks
65
In a petrographic microscope, there are two polarizers that are oriented perpendicular to each other. How would this kind of configuration assist in the analysis of a thin section
> When polarized light passes through the mineral, it interacts with the crystal structure are undergo changes in polarization state.
> The analyzer allows only the light affected by the mineral to pass through, thus allowing the viewer to see optical interference patterns and colors what would aid in idenifitying the said mineral
66
Suppose light is coming from a mateiral with an index of refraction of 1.5 is passing through a anohter transparent mineral from an angle of 30 degrees. Calculate the angle of refeaction of the index of refraction of the other material is 3
(1.5/3) Sin30 = SinX
x= 14.47 degrees
67
What would be the IUGS color index of a rock with a volume of 15% K-felds, 5% Qtz, 65% Potassic Plagioclase, and 15% Ferromagnesian minerals (Hornblende
(15 / (15+5+35+15)*100 = 15%
Leucrocratic
68
What would be the IUGS classificaiton of a pyroclatic debris with 50% Blocks and Bombs, 25% Ash, and 25% Lapilli
Tuff Breccia
69
A rock with the modal mineralogy of 50% Cpx, 30% Ol and 20% Hbl would be classified as
Olivine Hornblende Pyxoxenite
70
Matter during the fist few microseconds of the big bang existed in its most fundamental form as a _____
Quark Soup
71
Formation of atomic nuclei began about_______ after the Big Bang
13.8 sec
72
a faint glow of electromagnetic radiation that fills the observable universe. It is a crucial component of the evidence supporting the Big Bang theory of the origin of the universe.
Cosmic Microwave Background Radiation
73
total radiant energy emitted by an astronomical body
Absolute Luminosity
74
The Distance of the star can be determined by
A comparison of its absolute and apparent luminosity
75
a fundamental cosmological parameter that quantifies the current rate of expansion of the universe
Hubble Constant
76
The age of the universe
13.7 bya
77
basic units in the heirarchy of heavenly bodies in which matter continues to eveolve by nuclear reactions
Stars
78
Stars less massive than the Sun
Red dwarfs
79
Relation of emitted light from distance
Light intensity emitted from a star decreases as the distance squared increases
80
Define apparent luminosity
radiant power received by the telescope per sq cm
81
Define recessional velocities
velocities at which celestial objects are moving away from an observer or a reference point due to the expansion of the universe.
82
Enumerate the heirarchy of heavenly bodies in decreasing order
Galaxy cluster
Galaxy
Stars, pulsars and black holes
Planets
Satellites
comets
asteroids
meteoroids
dust particles
83
The spaces between stars contains clouds made up of
> H and He during intial universal expansion
> Elements with high atomic numbers from stellar remnants
> H and C compounds
84
What is the Hertzsprung-Russell diagram
>Plots the temperature of the stars vs luminosity or color vs adsolute magnitude
85
Evolutionary Stages in the HR diagram
> Main Sequence
> Red Giant and Supergiants
> White dwarf stars
86
Give examples of the nuclear reactions in the nucleosynthesis model
>Proton-Proton Chain
>CNO Cycle
>Triple Alpha Process
87
Nuclear Fusion VS Nuclear Fission
>Nuclear fusion involves the fusion of two light nuclei to form a heavier nucleus
>Nuclear fission involves splitting an atomic nucleas into two or more lighter nuclei
88
Enumerate the different types of meteorites
> Iron Meteorites
> Stony-Iron
>Iron
89
The three types of Nucleosynthesis
>Big bang Nucleosynthesis
>Stellar nucleosynthesis
> Supernova nucleosynthesis
90
Definition of Nucleosynthesis
process of element (nuclei) formation.
91
How did the doppler effect helped in calculating the recessional velocity of galaxies?
> The Doppler effect is the change in frequency or wavelength of a wave in relation to an observer moving relative to the source of the wave
> When a celestial object is moving relative to an observer on Earth, the motion causes a shift in the wavelength of the emitted light. This shift is known as the redshift (moving away) or blueshift (moving towards)
92
How is a star born?
> Interstellar gas cloud contracts due to external disturbances such as shockwaves form nearby supernovas
> Temperate increases and energy radiates
> Hydrogen fusion begins when temperature reaches 20x10^6 K
93
Why is the Hertzsprung-Russell diagram important
>it enables astronomers to determine a star's initial structure and evolutionary stage by determining its position in the diagram
94
What is the Oddo-Harkins rule and why it is possible?
>According to the Oddo-Harkins rule, elements with even atomic numbers are aubdant than its odd counterparts
> Since helium (atomic number 2) is a major element for nucleosynthesis, its fusion would produce more elements with even atomic number
> The parity that comes with even numbers would cause offsets between the spinning proton, thus contributing to its stability
95
Why is the sun considered as a second-generation star
>Unlike 1st generation stars, the hydrogen fusion of the sun is carried out by the CNO cycle
>also contains highher atomic number than helium
96
How did lithium (Li), beryllium (Be), and boron (B) form?
> these lighter elements are formed by cosmic ray spallation which is a process that involves the impact of cosmic rays with matter
> the resulting collision causes the spalling of nucleaons which produces Li, Be and B
97
Describe the CNO in terms of chemical equation
At physocals
98
Why is Iron signigicantly abundant compared to other elements with similar atomic numbers
> Fusion processes red giants allow the production of heavier atoms by fusing alpha particles with carbon 12 nuclei, which turns to Oxygen 16, then Neon 20 until it stops the the heaviest atom produced which is Nickel 56
>Nickel 56 is unstable so it decays to Cobalt and then decays to the stable Iron
99
What would be the reason as to the compositional difference between the core of the start than its surrounding shell
> Different kinds of nuclear reactions takes place simultaneously in the core and outer shell of the star
>The core is where most nuclear reaction take place, particularly the proton-proton chain reaction which fuses hydrogen into helium
>The shell is made up of accumulated helium with some minor fusion reactions that yields heavier elements
