Geology Exam 2 Flashcards

Questions and Answers

What is crystallization?

The cooling of magma which results in the systematic arrangement of ions into orderly patterns.

What is the rate of cooling and the environment of formation for an extrusive igneous rock?

Slow

Could be fast or slow

Fast (correct)

________ describes the range in particle sizes in a detrital sedimentary rock.

Sorting

Which process will remove CO2 from the atmosphere and sequester it?

Deposition of carbonate sediments Signup and view all the answers

There are no sediments on the deep seafloor.

False Signup and view all the answers

What is diagenesis?

The textural, compositional, and other changes that occur to sediments after deposition. Signup and view all the answers

These large crystals in metamorphic rocks are called ________.

Porphyroblasts Signup and view all the answers

Which of the following is not an environment of metamorphism?

Deposition of sediments near a river Signup and view all the answers

Which style of metamorphism will be generated by a magma pluton?

Contact Signup and view all the answers

________ metamorphism tends to occur in regions where massive amounts of sedimentary or volcanic materials accumulate.

Burial Signup and view all the answers

In which geologic setting is the most widespread occurrence of hydrothermal metamorphism found?

Along the axis of a mid-ocean ridge system Signup and view all the answers

Which tectonic boundary is associated with regional metamorphism?

Convergent Signup and view all the answers

________ metamorphism will occur where two blocks of rock are grinding against each other.

Fault zone Signup and view all the answers

What is the average increase in temperature along the geothermal gradient in the upper crust?

25°C per km Signup and view all the answers

Metamorphism ends when the rock begins to melt.

True Signup and view all the answers

________ refers to a mineral's intensity and quality of reflected light.

Luster Signup and view all the answers

What is the main difference between minerals and rocks?

Minerals are composed of atoms bonded together in a symmetric arrangement, whereas rocks are generally composed of aggregates of minerals. Signup and view all the answers

Which of the following mineral identification techniques would most easily identify calcite?

Effervescence Signup and view all the answers

Which of the following minerals is most common in crustal rocks?

Feldspar Signup and view all the answers

What is the most common element in the continental crust?

Oxygen Signup and view all the answers

A ________ is a solid, naturally occurring, cohesive substance composed of minerals or mineral-like materials.

Rock Signup and view all the answers

Which of the following is not part of the definition of a mineral?

Organic Signup and view all the answers

Graphite is a good lubricant because:

It has weak bonds in one direction. Signup and view all the answers

Which of the following is NOT part of the definition of a mineral?

Contains silicon and oxygen. Signup and view all the answers

You are attempting to identify a mineral. You determine that it does indeed have cleavage; therefore, your mineral cannot possibly be __________.

Quartz Signup and view all the answers

What are the two groups of feldspar minerals called?

Potassium feldspar and plagioclase Signup and view all the answers

Which of the following is a rock composed of non-mineral matter?

Coal Signup and view all the answers

The advantage of bronze over copper is:

Bronze is harder than copper. Signup and view all the answers

Which statement is NOT true?

All minerals have cleavage. Signup and view all the answers

Which of the following is not one of the three primary ways minerals can form?

Hybridization of chemically saturated fluid. Signup and view all the answers

Which of the following is the hardest known natural substance?

Diamond Signup and view all the answers

Ferromagnesian minerals are those that contain a great deal of ________.

magnesium and iron Signup and view all the answers

Define the tenacity of a mineral.

Resistance to breaking or deforming. Signup and view all the answers

Which property is the least reliable when identifying a mineral?

Color Signup and view all the answers

________ is the study of mineral materials.

Mineralogy Signup and view all the answers

Which two minerals define a felsic composition for an igneous rock?

Quartz and potassium feldspar Signup and view all the answers

What is a volatile referred to in geology?

Gases dissolved in a magma Signup and view all the answers

What creates the small holes found in a vesicular texture?

Volatiles Signup and view all the answers

________ is a felsic igneous rock with a meringue-like vesicular texture, consisting of very small holes, created by small shards of volcanic glass.

Pumice Signup and view all the answers

Welded tuff consists of ash surrounding large, jagged, irregularly-shaped pieces of material. What is this material and where does it come from?

Rock fragments that erupted from the volcano Signup and view all the answers

Temperatures will decrease with increasing depth into the Earth.

False Signup and view all the answers

________ is molten rock that is below the Earth's surface and retains most of its volcanic gases.

Magma Signup and view all the answers

Match the igneous composition to its silica content.

60% = Intermediate 50% = Mafic 70% = Felsic Signup and view all the answers

Silica increases the viscosity and decreases magma temperature (which will also increase the viscosity).

True Signup and view all the answers

Select the choice below that best describes the role of volatiles in an ascending magma.

Volatiles will expand with decreasing pressure, then melt upward. Signup and view all the answers

What is the term used to describe increased temperature with depth in the Earth?

Geothermal gradient Signup and view all the answers

Magma is molten rock below the surface that retains its volatiles. Lava is molten rock that has reached the surface and is losing or has lost its volatiles.

True Signup and view all the answers

Which igneous texture has visible crystals that are a few millimeters across?

Phaneritic Signup and view all the answers

Which is the intrusive igneous textures?

Pegmatitic Signup and view all the answers

Which of the following minerals is not a ferromagnesian mineral?

Potassium feldspar Signup and view all the answers

Of the following substances, which are the common elements in igneous rocks?

Si, O, Al, K, Ca, Fe, Mg Signup and view all the answers

Igneous rocks with an andesitic composition are found along volcanic island arcs.

True Signup and view all the answers

Which of the following substances is not a volatile found in magma?

O2 Signup and view all the answers

Match the intrusive igneous rock with its extrusive equivalent.

Granite = Rhyolite Diorite = Andesite Gabbro = Basalt Signup and view all the answers

Which of the following methods of transportation will result in the best degree of sorting, with all the particles being roughly the same size?

Wind Signup and view all the answers

Approximately 75 percent of the planet's landmasses are covered by sedimentary and sedimentary rocks.

True Signup and view all the answers

________ describes the range in particle sizes in a detrital sedimentary rock.

Sorting Signup and view all the answers

Which of the following makes up the sediment that forms an organic sedimentary rock?

Plant and animal remains Signup and view all the answers

________ are fragments of preexisting materials that have been broken down through the processes of weathering.

Sediments Signup and view all the answers

Which of the following best describes the appearance and composition of a conglomerate?

Rounded fragments; poorly sorted Signup and view all the answers

What are two examples of inorganic limestone?

Travertine and crystalline limestone Signup and view all the answers

What is the most common sedimentary rock?

Shale Signup and view all the answers

________ processes, such as evaporation or precipitation, can precipitate chemical sediments.

Inorganic Signup and view all the answers

Folding, deformation, and metamorphism of organic material will produce ________ coal.

anthracite Signup and view all the answers

Detrital sedimentary rocks are classified according to grain size, whereas chemical sedimentary rocks are classified based on their dominant minerals.

True Signup and view all the answers

Which minerals are the main constituents in most sedimentary rocks?

Quartz and feldspars Signup and view all the answers

Which rock type can contain fossils?

Sedimentary rocks Signup and view all the answers

Shales are well cemented because of the high number of pore spaces.

False Signup and view all the answers

The primary basis for classifying detrital rocks is , whereas the primary basis for classifying chemical rocks is .

Particle size; mineral composition Signup and view all the answers

________ metamorphism will occur where two blocks of rock are grinding against each other.

Fault zone Signup and view all the answers

________ is the process by which new mineral grains larger than the original mineral grains form as a result of metamorphic heat.

Recrystallization Signup and view all the answers

Metamorphism ends when the rock begins to melt.

True Signup and view all the answers

Generally speaking, how does the chemical composition of most metamorphic rocks compare to that of the parent rock?

Their chemical composition will be nearly the same. Signup and view all the answers

________ can produce intricately folded rocks.

Differential stress Signup and view all the answers

Which of the following lists of metamorphic rocks places the rocks in order from lowest metamorphic grade to highest?

Slate, phyllite, schist, gneiss Signup and view all the answers

Which of the following is not an example of foliation?

Recrystallization of spherical minerals to create layers parallel to the direction of greatest stress. Signup and view all the answers

What is the most important factor driving metamorphism?

Heat Signup and view all the answers

What kind of temperature conditions will exist in a burial metamorphism environment?

Low temperature Signup and view all the answers

What is foliation?

Roughly parallel layers of mineral crystals aligned perpendicular to the direction of pressure. Signup and view all the answers

Which of the following environments would most likely produce metamorphism in fault zones?

Great depth and high temperatures. Signup and view all the answers

Sedimentary rocks are always the parent rocks for metamorphic rocks.

False Signup and view all the answers

What is the mineral name for table salt?

Halite Signup and view all the answers

Conchoidal fractures are indicative of the mineral ________.

Quartz Signup and view all the answers

Which statement is true?

A rock can be composed of almost entirely one mineral. Signup and view all the answers

Crystallization of molten rock will produce ________ rocks.

Igneous Signup and view all the answers

Which kind of mineral tenacity refers to a mineral being deformed by being hammered without breaking?

Malleable Signup and view all the answers

The ________ are the mineral class that accounts for more than 90 percent of the Earth's crust.

Silicates Signup and view all the answers

What three components make up most magmas?

Lava, ash, and gas Signup and view all the answers

When magma forms, it rises up through the crust. Why does magma rise?

It is less dense. Signup and view all the answers

Which statement is correct about crystallization of magma?

Crystallization is the cooling of magma which results in the systematic arrangement of ions into orderly patterns. Signup and view all the answers

Study Notes

Mineral Identification and Properties

Luster is a mineral's intensity and quality of reflected light.
Calcite is easily identified through effervescence when reacting with acid.
Feldspar is the most common mineral in crustal rocks.

Rocks and Minerals

Minerals consist of atoms bonded in a symmetric arrangement; rocks are aggregates of minerals.
A rock is a solid, naturally occurring cohesive substance made from minerals or mineral-like materials.
Not all minerals are organic; specific characteristics must be met for classification.

Element Composition and Rock Types

Oxygen is the most common element in the continental crust.
Organic sedimentary rocks are predominantly composed of plant and animal remains, while coal is a non-mineral rock type.
Common elements in igneous rocks include silicon, oxygen, aluminum, potassium, calcium, iron, and magnesium.

Magma and Volcanoes

Magma retains volatiles, while lava has lost them upon surfacing.
Volatiles in magma expand as pressure decreases, facilitating magma ascent.
The geothermal gradient describes the increase in temperature with depth.

Texture and Composition in Rocks

Phaneritic texture refers to igneous rocks with visible crystals, while pegmatitic textures indicate larger crystals.
Sorting describes the range of particle sizes in detrital sedimentary rocks; conglomerates are poorly sorted with rounded fragments.
Quartz displays conchoidal fractures, indicating its crystalline structure.

Metamorphism

Heat is a key factor in driving metamorphism, which can produce foliation in rocks.
Burial metamorphism occurs at low temperature conditions, while fault zone metamorphism involves significant stress and pressure.
Metamorphic rocks typically retain a chemical composition similar to their parent rock, though changes can occur during the process.

Mineral Classes and Composition

Silicates constitute more than 90% of the Earth's crust, demonstrating their prevalence.
Crystallization involves the systematic arrangement of magma ions into solid structures.
Foliation results in roughly parallel layers of mineral crystals aligned perpendicularly to applied pressure.

Environmental Impact and Rock Formation

Organic processes can lead to the formation of chemical sediments through evaporation or precipitation.
Diagenesis refers to changes in sediments after deposition, which may affect composition and texture.
Sedimentary rocks are vital for fossil preservation due to their formation conditions.### Metamorphism Types and Processes
Contact Metamorphism: Occurs due to proximity to a hot magma body, with temperature being the primary factor.
Burial Metamorphism: Involves the accumulation of sedimentary or volcanic materials, pushing older rocks deeper into the crust.
Hydrothermal Metamorphism: Most common at mid-ocean ridge systems, where hot fluids circulate and alter rock.
Regional Metamorphism: Associated with convergent tectonic boundaries, where rocks experience high pressures and temperatures.
Fault Zone Metamorphism: Happens when two blocks of rock grind against each other, causing deformation and heat.

Geothermal Gradient

Temperature Increase: Average geothermal gradient in the upper crust is approximately 25°C per km, reflecting how temperature rises with depth.

Key Concepts

Metamorphism Termination: Occurs when rock temperatures reach the melting point, marking the transition from metamorphic to igneous processes.
Sediment Deposition: Key factor in geological processes, notably near riverbanks, leading to sedimentary rock formation.

Geological Settings

Hydrothermal Activity: Commonly found along mid-ocean ridges, indicating significant geological activity and interactions between crust and mantle.
Pressure Zones: High pressure in subduction zones contributes to regional metamorphism, impacting surrounding rock structures.

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Geology Exam 2 Flashcards

Questions and Answers

What is crystallization?

What is the rate of cooling and the environment of formation for an extrusive igneous rock?

________ describes the range in particle sizes in a detrital sedimentary rock.

Which process will remove CO2 from the atmosphere and sequester it?

There are no sediments on the deep seafloor.

What is diagenesis?

These large crystals in metamorphic rocks are called ________.

Which of the following is not an environment of metamorphism?

Which style of metamorphism will be generated by a magma pluton?

________ metamorphism tends to occur in regions where massive amounts of sedimentary or volcanic materials accumulate.

In which geologic setting is the most widespread occurrence of hydrothermal metamorphism found?

Which tectonic boundary is associated with regional metamorphism?

________ metamorphism will occur where two blocks of rock are grinding against each other.

What is the average increase in temperature along the geothermal gradient in the upper crust?

Metamorphism ends when the rock begins to melt.

________ refers to a mineral's intensity and quality of reflected light.

What is the main difference between minerals and rocks?

Which of the following mineral identification techniques would most easily identify calcite?

Which of the following minerals is most common in crustal rocks?

What is the most common element in the continental crust?

A ________ is a solid, naturally occurring, cohesive substance composed of minerals or mineral-like materials.

Which of the following is not part of the definition of a mineral?

Graphite is a good lubricant because:

Which of the following is NOT part of the definition of a mineral?

You are attempting to identify a mineral. You determine that it does indeed have cleavage; therefore, your mineral cannot possibly be __________.

What are the two groups of feldspar minerals called?

Which of the following is a rock composed of non-mineral matter?

The advantage of bronze over copper is:

Which statement is NOT true?

Which of the following is not one of the three primary ways minerals can form?

Which of the following is the hardest known natural substance?

Ferromagnesian minerals are those that contain a great deal of ________.

Define the tenacity of a mineral.

Which property is the least reliable when identifying a mineral?

________ is the study of mineral materials.

Which two minerals define a felsic composition for an igneous rock?

What is a volatile referred to in geology?

What creates the small holes found in a vesicular texture?

________ is a felsic igneous rock with a meringue-like vesicular texture, consisting of very small holes, created by small shards of volcanic glass.

Welded tuff consists of ash surrounding large, jagged, irregularly-shaped pieces of material. What is this material and where does it come from?

Temperatures will decrease with increasing depth into the Earth.

________ is molten rock that is below the Earth's surface and retains most of its volcanic gases.

Match the igneous composition to its silica content.

Silica increases the viscosity and decreases magma temperature (which will also increase the viscosity).

Select the choice below that best describes the role of volatiles in an ascending magma.

What is the term used to describe increased temperature with depth in the Earth?

Magma is molten rock below the surface that retains its volatiles. Lava is molten rock that has reached the surface and is losing or has lost its volatiles.

Which igneous texture has visible crystals that are a few millimeters across?

Which is the intrusive igneous textures?

Which of the following minerals is not a ferromagnesian mineral?

Of the following substances, which are the common elements in igneous rocks?

Igneous rocks with an andesitic composition are found along volcanic island arcs.

Which of the following substances is not a volatile found in magma?

Match the intrusive igneous rock with its extrusive equivalent.

Which of the following methods of transportation will result in the best degree of sorting, with all the particles being roughly the same size?

Approximately 75 percent of the planet's landmasses are covered by sedimentary and sedimentary rocks.

________ describes the range in particle sizes in a detrital sedimentary rock.

Which of the following makes up the sediment that forms an organic sedimentary rock?

________ are fragments of preexisting materials that have been broken down through the processes of weathering.

Which of the following best describes the appearance and composition of a conglomerate?

What are two examples of inorganic limestone?

What is the most common sedimentary rock?

________ processes, such as evaporation or precipitation, can precipitate chemical sediments.

Folding, deformation, and metamorphism of organic material will produce ________ coal.

Detrital sedimentary rocks are classified according to grain size, whereas chemical sedimentary rocks are classified based on their dominant minerals.

Which minerals are the main constituents in most sedimentary rocks?

Which rock type can contain fossils?

Shales are well cemented because of the high number of pore spaces.

The primary basis for classifying detrital rocks is ________, whereas the primary basis for classifying chemical rocks is ________.

________ metamorphism will occur where two blocks of rock are grinding against each other.

________ is the process by which new mineral grains larger than the original mineral grains form as a result of metamorphic heat.

Metamorphism ends when the rock begins to melt.

Generally speaking, how does the chemical composition of most metamorphic rocks compare to that of the parent rock?

________ can produce intricately folded rocks.

Which of the following lists of metamorphic rocks places the rocks in order from lowest metamorphic grade to highest?

Which of the following is not an example of foliation?

What is the most important factor driving metamorphism?

What kind of temperature conditions will exist in a burial metamorphism environment?

The primary basis for classifying detrital rocks is , whereas the primary basis for classifying chemical rocks is .