IX. Question (226-275) Flashcards
__________ is the gangue mineral that occur where there is the highest concentrations of sphalerite and galena in the uppermost zone of a VMS deposit.
Barite
Barite (BaSO₄) is a common gangue mineral in volcanogenic massive sulfide (VMS) deposits, especially in the uppermost zones where sphalerite (ZnS) and galena (PbS) are concentrated. It forms as a result of hydrothermal activity and is often associated with sulfide mineralization in these deposits.
___________ form where streams carrying an abundant supply of sediment enter a still body of water that lacks extensive wave and current scour.
a) bed-load deltas
b) suspended-load deltas
c) deltas
d) lacustrine deposits
c) deltas
Deltas form where streams carrying an abundant supply of sediment enter a still body of water (like a lake or sea) that lacks extensive wave and current scour. The decrease in flow velocity causes the sediments to settle and accumulate, forming a delta.
___________ makes plates move from spreading centers.
a. Slab pull
b. The asthenosphere
c. Ridge push
d. The lithosphere
e. nota
c) Ridge push
Ridge push is a tectonic force that occurs at spreading centers (mid-ocean ridges), where newly formed lithosphere is elevated compared to older, cooler, and denser lithosphere. Gravity causes the elevated lithosphere to push away from the ridge, making the plates move.
____________ is a type of fold where the arched layers dips away from fold center (the axis).
anticline
____________ is the smallest distinctive layer in volcanic sequences
a. bed
b. flow
c. member
d. toungue
b) flow
A “flow” is the smallest distinctive layer in volcanic sequences, typically representing a single eruption or lava flow event. It is characterized by a relatively uniform composition and texture.
_____________ An absolutely impermeable unit that will neither store nor transmit water.
a. Aquifuge
b. aquiclude
c. aquifer
d. aquitard
a) Aquifuge
An aquifuge is an absolutely impermeable geological unit that neither stores nor transmits water. It completely blocks the movement of groundwater.
_____________ refers to the addition of molecular water from the mineral to the fluid.
Dehydration
Dehydration is a geological process where molecular water is released from a mineral into a fluid phase, often during metamorphism or magmatic processes.
_____________ happens when sediments behave like a liquid during earthquake that may cause foundation failures.
Liquefaction
_____________ are compounds whose carbon atoms are double bonded to each other and form rings; have a structure based on hexagonal ring of carbons with alternate simple and double bonds.
a. Aromatics
b. Napthenes
c. Alkanes
d. Alkenes
e. None of the above
a) Aromatics
Aromatic compounds are hydrocarbons that contain a planar, cyclic structure with conjugated π electrons, typically forming a hexagonal ring with alternating single and double bonds (like benzene).
_____________ skarns result from the replacement of dolomite.
Magnesian skarns
Magnesian skarns are formed when dolomitic rocks are replaced during contact metamorphism, typically resulting in magnesium-rich mineral assemblages like forsterite, diopside, and phlogopite.
_____________ weathering leads to dissolution of minerals.
Chemical weathering
Chemical weathering involves the breakdown of minerals through chemical reactions, such as dissolution, hydrolysis, oxidation, and carbonation, resulting in the formation of new minerals and the release of dissolved ions.
______________ are minerals with the same chemical composition but different crystal structure.
a. the law of constancy of interfacial angles
c. polymorph
b. isomorph
d. cleavage
c. polymorph
______________ currents make the lithosphere move over the asthenosphere.
a. Wind
b. Convection
c. Electric
d. Eddy
e. nota
b. Convection
Convection currents within the Earth’s mantle cause the lithosphere to move over the asthenosphere. These currents are driven by the heat from the Earth’s core, causing hot, less dense material to rise and cooler, denser material to sink, creating a continuous flow that moves tectonic plates.
_______________ is a mixture of liquid rock, crystals and gas characterized by a wide range of chemical compositions with high temperature, and properties of a liquid.
a. obsidian
c. lava
b. igneous rock
d. magma
d. magma
_______________ is the ratio of gold to the sum of gold+silver, multiplied by 1000.
Fineness
Fineness is a measure of the purity of precious metals, especially gold, and is calculated as the ratio of the mass of pure gold to the combined mass of gold and silver in an alloy, multiplied by 1000.
_______________ is the smallest distinctive layer in volcanic sequences
a. bed
b. flow
c. member
d. tongue
b. flow
________________ is refers to the changes in mineral assemblage and texture that result from subjecting rock to pressure and temperatures different from those under the rock which originally formed.
a. diagenesis
c. foliation
b. metamorphism
d. banding
b. metamorphism
________________1. The boundaries between (The core and two) distinguishable shells of the earth
Discontinuities
In geology, discontinuities are boundaries that separate different layers within the Earth’s interior, such as the core, mantle, and crust. Notable discontinuities include the Mohorovičić discontinuity (Moho) between the crust and mantle, and the Gutenberg discontinuity between the mantle and the outer core.
________________1. The boundaries between (The core and two) distinguishable shells of the earth
Gutenberg Discontinuity
The Gutenberg Discontinuity is the boundary between the Earth’s mantle and the outer core. It is located at a depth of about 2,900 kilometers (1,800 miles) below the Earth’s surface and is characterized by a sudden change in seismic wave velocities, indicating a transition from solid mantle material to the liquid outer core.
________________10. A fold with parallel lines
Isoclinal fold
An isoclinal fold is a type of fold in which the limbs are parallel to each other, typically resulting from intense compressional forces.
________________11. The plants collectively of a given formation age or region
Flora
Flora refers to the collective plant life that is characteristic of a specific geological formation, age, or region.
________________12. Sandstone in which grains of dark, fine-grained igneous rocks are abundant
Graywacke
Graywacke is a type of sandstone characterized by a significant amount of dark, fine-grained rock fragments and a clay matrix, giving it a dark and dirty appearance.
________________13. Floating organisms
________________14. The benthonic environment near the shore and distinct with the neritic zone.
________________14. The benthonic environment near the shore and distinct with the neritic zone.
Littoral Zone
The littoral zone is the part of a sea, lake, or river that is close to the shore. In marine environments, it often overlaps with the neritic zone and is characterized by abundant sunlight and nutrient availability, making it rich in marine life.
