GEO Chapters 1 & Chapter 2 - Minerals & The Rock Cycle = Metamorphic, Igneous and Sedimentary Rocks.

6. Hornblende has a hardness of: a. 1 b. 2-3 c. 4 d. 5-6 e. 7

5-6

Hardness describes a mineral's __________.

resistance to being scratched

Describe the distribution of sedimentary deposits you would expect to find on a delta.

sand in channels, mud on floodplain

Which group of minerals are the most abundant in the Earth's crust? a. sulfides b. carbonates c. silicates d. chlorides

silicates

All silicate minerals contain which two elements? a. iron, silicon b. silicon, sodium c. oxygen, carbon d. silicon, oxygen

silicon, oxygen

Do metamorphic rocks look like the preexisting rock from which they form?

sometimes, but not always

Crystal habit is the shape that a mineral develops by the repetition of __________.

the basic unit cell of a mineral

Hornblende has _____ cleavage planes at _____ angles. a. three; non-90° b. four; non-90° c. two; non-90° d. two; 90° e. three; 90°

two; non-90°

A ________ is an open cavity in a volcanic rock formed by escaping gas. a. porphyrocryst b. vesicle c. phenocryst d. xenocryst

vesicle

1. Sample 7, scoria, has voids left by gas bubbles. This results in what kind of texture? a. vesicular b. pegmatitic c. phaneritic d. porphyritic

vesicular

An aeolian sandstone___________________

was deposited by wind

3. Muscovite and Biotite have a hardness of: a. 1 b. 2-3 c. 4 d. 5-6 e. 7

2-3

Other than sand dunes in a desert environment, where else would you expect to find well-rounded and sorted sand deposits?

Beach

A mineral in the carbonate family; showing three planes of cleavage and a fizzing reaction to hydrochloric acid.

Calcite

What is the difference between magma and lava?

Magma is molten rock located below the surface; lava is molten rock erupted above ground.

Which of the following rock types is most abundant on Earth's land surface?

Sedimentary rocks

What is foliation?

banding in metamorphic rocks that results from the reorientation of minerals

15. In terms of mineral composition, both Fine-Grained Granite (sample 11) and Pegmatite (sample 12) are: a. felsic b. intermediate c. mafic d. ultramafic

felsic

Igneous rocks of felsic composition have __________ and __________ relative to mafic igneous rocks.

greater silica; lower melting temperature

Which of the following factors describe the conditions at a zone where low-grade regional metamorphism is occurring?

- low temperature - low pressure

9. What type of cleavage does Biotite have? a. 1 direction b. 2 direction at 90 degrees c. 2 direction, not at 90 degrees d. no cleavage

1 direction

7. Based on your observations, the most likely parent rock in our collection for Gneiss (sample 16) is: a. 11 (Fine-Grained Granite) b. 19 (Sandstone) c. 20 (Shale) d. 9 (Basalt)

11 (Fine-Grained Granite)

18. Which of the following metamorphic rocks in the collection show foliation? a. 13 (Mica Schist), 14 (Slate), 16 (Gneiss) b. 15 (Quatzite), 18 (Marble) c. all of the metamorphic samples (13-18) d. none of the metamorphic samples

13 (Mica Schist), 14 (Slate), 16 (Gneiss)

Which of the following exhibits three sets of cleavage at 90° angles? a. Feldspar b. Calcite c. Fluorite d. Galena e. Mica

Galena

A mineral made of oxidized hydrogen.

Ice

_____ igneous rocks are those that cool below the surface.

Intrusive

What is one characteristic of the Bishop Tuff and other rocks with this texture?

It contains pieces of other material, such as lava.

What is one reason slot canyons develop in the Navajo Sandstone?

It is resistant and homogenous.

An igneous rock becomes buried, is subject to high heat and pressure, and recrystallizes. This rock then is eroded, transported, deposited and subsequently lithified. Which rock types—in order—did the original igneous rock develop into? a. Metamorphic and sedimentary b. Sedimentary and metamorphic c. Igneous and sedimentary d. Metamorphic and igneous

Metamorphic and sedimentary

What is the name of the sedimentary rock deposited above the Bright Angel Shale?

Muav Limestone

17. What mineral is clearly visible as shiny "glitters" in Arkose (Sample 21)? a. Muscovite b. biotite c. hornblende d. calcite

Muscovite

Based on the diagram shown in the video, name two minerals that are unlikely to coexist in the same igneous rock.

Muscovite and pyroxene

Name one mineral present in the Vishnu Schist.

Muscovite mica

Based on what you learned in this video, what minerals make up rhyolite?

Quartz, K-feldspar, and plagioclase feldspars, with relatively fewer biotite and amphiboles

What type of igneous rock is found in the Owens River Gorge along with the Bishop Tuff?

Rhyolite

How is quartz sandstone metamorphosed into quartzite during contact metamorphism?

Sand grains are fused together because of high temperatures.

The micas (biotite and muscovite) exhibit what type of silicate structure?

Sheet

Which of the following best describes the term streak?

The color of a powdered form of a mineral produced by rubbing it across a hard surface.

Lava flows are typically finer grained than intrusive igneous rocks. Why? a. Intrusive magma is cooler because it is well insulated by the surrounding rock. b. Intrusive magma flows onto the Earth's surface and cools very slowly, allowing many small mineral grains to grow. c. The extrusive magma cools quickly so the mineral grains do not have time to grow. d. The extrusive magma, because it is deep below the surface, cools very slowly producing very small mineral grains.

The extrusive magma cools quickly so the mineral grains do not have time to grow.

What is the origin of the Vishnu Schist?

The remains of an ancient mountain range

What does an igneous rock with a pyroclastic texture tell a geologist?

The rock was likely formed by a violent volcanic eruption.

Which of the following best describes mineral habit?

The shape a mineral grows into, given sufficient space.

What is an accurate description of the silicon-oxygen tetrahedron?

The silicon-oxygen tetrahedron is a four-sided figure with a silicon atom in the middle bonded to four neighboring oxygen atoms.

Other than space, what two additional factors are significant for a crystal to attain habit?

Time and necessary elements

All of the feldspar minerals have the same type of cleavage. a. True b. False

True

Basalt is the aphanitic or fine-grained equivalent of gabbro. a. True b. False

True

Calcite and dolomite are both carbonate minerals. a. True b. False

True

Which of the following describes a texture containing bubble-shaped cavities?

Vesicular

11. The collection list labels sample 22 as a Conglomerate. This means it should have rounded particles of greater than 2 mm. Do you agree with the name of your sample? a. Yes, it should be called a conglomerate b. No, it should be labeled as a sandstone c. No, it should be labeled as a breccia d. No, it should be labeled as a shale

Yes, it should be called a Conglomerate

What large, overall igneous feature makes up the Sierra Nevada Mountains in California?

batholith

Minerals must be solid, have an orderly atomic structure, have a recognized chemical composition, be naturally occurring, and __________.

be generally inorganic in origin

What discourages minerals from achieving habit?

enclosed spaces

6. Scoria (Samples 7), Obsidian (sample 8) and Basalt (sample 9) are examples of ____________ igneous rocks. a. extrusive b. intrusive c. non-extrusive d. contrusive

extrusive

2. The texture of Obsidian (sample 8) is: a. glassy b. pegmatitic c. vesicular d. porphyritic

glassy

1. Milky quartz (sample #1) doesn't have a glassy luster; more often it looks like it is coated in oil. In the text, this luster is referred to as: a. greasy b. pearly c. waxy d. vitreous

greasy

What is one way a glassy texture forms?

lava cools rapidly

Which of the following factors describes the conditions at a zone where contact metamorphism is occurring?

low pressure, high temperature

The appearance or quality of light reflected from the surface of a mineral is known as ___________ a. luster b. cleavage c. color d. fluorescence

luster

10. Name the abundant mineral that you see in Mica Schist (sample 13)? a. muscovite b. biotite c. calcite d. quartz

muscovite

13. Identify the 2 principal minerals of sample 12: a. quartz and potassium feldspar b. hornblende and biotite c. muscovite and biotite d. calcite and muscovite

quartz and potassium feldspar

Which of the following is evidence of glaciation in Yosemite National Park?

U-shaped valleys, striations in granite

What is a metamorphic aureole?

a ring of metamorphic rocks adjacent to an igneous intrusion

8. Sample #10, Trachyte Porphyry, has a felsic composition. The white phenocrysts in the rock are most likely: a. muscovite b. a white-colored feldspar c. calcite d. biotite

a white-colored feldspar

Which of the following defines depositional environment?

an area where sediment was deposited under certain conditions in Earth's past

15. What is one difference between Travertine (samples 23) and Limestone (sample 24)? a. appearance b. mineral composition c. 23 is pyroclastic and 24 is sedimentary d. 23 is sedimentary and 24 is pyroclastic

appearance

In which setting would regional metamorphism be most likely? a. at shallow depths below an oceanic ridge or rift zone b. at shallow depths along major transform faults in the continental crust c. at great depths in the crust where two continents are colliding d. at shallow depths beneath the seafloor where water pressures are immense

at great depths in the crust where two continents are colliding.

What is the name of dark-colored mica? a. calcite b. biotite c. quartz d. olivine

biotite

Which of the 6 minerals in our collection will react (fizz) in the presence of hydrochloric acid? a. calcite b. feldspar c. quartz d. biotite e. muscovite

calcite

9. The texture of Porphyry (sample 10) indicates a. change of environment during the cooling process b. extremely slow cooling c. extremely rapid cooling d. large amounts of volatiles

change of environment during the cooling process

Cross-bedding in the petrified dune indicates________________

changes in wind direction

The tendency of a mineral to break along planes of weak chemical bonds is known as ________________ a. cleavage b. luster c. tenacity d. crystal habit

cleavage

10. The texture of Granite Fine-Grained (# 11) has been mislabeled in the collection. This rock should be classified as _____________ a. coarse-grained b. fine-grained c. porphyritic d. vesicular

coarse-grained

Quartz exhibits __________.

conchoidal fracture

5. Basalt (Sample 9) is mostly composed of: a. dark silicate minerals b. light silicate minerals c. minerals from the sulfate and carbonate groups d. smoky quartz and Muscovite

dark silicate minerals

What mineral is the hardest known substance in nature? a. silicate b. native gold c. diamond d. muscovite

diamond

4. Basalt [Sample 9] (no line at bottom of number) has what texture? a. fine-grained b. coarse-grained c. porphyritic d. glassy

fine-grained

Coal beds originate in ________. a. shallow lakes in a dry, desert region b. channels of fast-moving streams c. deep, marine basins below wave action d. freshwater coastal swamps and bogs

freshwater coastal swamps and bogs

What would you call a granite that has undergone metamorphism and now exhibits foliation?

gneiss

Which of the following metamorphic rocks could have a parent rock (protolith) of shale?

gneiss, phyllite, schist, slate

Detrital sedimentary rocks are classified (named) based on the ________. a. colors of the cementing minerals b. grain sizes of the detrital particles c. compositions of soluble minerals d. degree of compaction and lithification

grain sizes of the detrital particles

15. According the the rock and mineral identification sheet, which mineral in the collection is representative of the amphibole group? a. hornblende b. biotite mica c. quartz d. limestone

hornblende

Which of the following minerals contains iron and/or magnesium? a. quartz b. feldspar c. hornblende d. muscovite

hornblende

Which of the following is associated with the metamorphic rock phyllite?

intermediate-grade metamorphism

14. Granite Fine-Grained (Samples 11) and Pegmatite (12) are examples of____________ igneous rocks: a. intrusive b. extrusive c. non-intrusive d. contrusive

intrusive

7. Granite Fine-Grained (Sample 11) and Pegmatite (sample 12) are examples of _____________ igneous rocks? a. intrusive b. extrusive c. contrusive d. vesicular

intrusive

A phaneritic texture is characteristic of a(n) __________ igneous rock that cooled __________.

intrusive; below the surface

8. Concerning Shale (sample # 20), which is the most correct statement? a. it is a detrital sedimentary rock b. it is a chemical sedimentary rock c. it is a metamorphic rock d. it is a cementing agent for sedimentary rocks

it is a detrital sedimentary rock

3. The silicate material which makes up Obsidian (sample 8) lacks which of the following usual attributes of minerals? a. lacks a crystalline structure b. lacks SiO2 c. it is not inorganic d. it is not naturally occurring

lacks a crystalline structure

14. According to the rock and mineral explanation sheet, which rock in the collection is composed principally of calcite, mineral #5? a. limestone b. coarse-grained granite c. porphyry d. mica schist

limestone

Which of the following best describes confining pressure and the location in which it occurs?

moderate pressures at shallow depths

The Great Unconformity separates the Tonto group from ______________

much older metamorphic and igneous rock

9. Sample 20 is called a shale, but if your sample does not have a layered appearance, it may actually be more correct to call it a: a. mudstone b. sandstone c. claystone d. blockstone

mudstone

12. What type of cleavage does quartz have? a. 1 direction b. 2 directions, at 90 degrees c. 2 directions, NOT at 90 degrees d. no cleavage

no cleavage

Which of the following describes the orientation of the long axes of rocks and mineral grains in relationship to the stress applied?

- Mineral grains are oriented parallel to the direction of the weakest stress applied. - The long axis of a rock is parallel to the direction of the weakest stress applied.

3. Which of the metamorphic rocks in the collection DO NOT show foliation? a. 15 (Quatzite), 18 (Marble) b. 13 (Mica Schist), 14 (Slete), 16 (Gneiss) c. all of the metamorphic samples (13-18) d. none of the metamorphic samples

15 (Quatzite), 18 (Marble)

4. Which of the metamorphic samples is composed of the mineral calcite? a. 15 (Quartzite) b. 16 (Gneiss) c. 17 (Talc) d. 18 (Marble)

18 (Marble)

13. The most likely parent rock in our collection for Quartzite (sample 15) is a. 19 (Sandstone) b. 10 (Porphyry) c. 20 (Shale) d. 9 (Basalt)

19 (Sandstone)

19. Which of the sedimentary samples in our collections are detrital sedimentary rocks? a. 19 (Sandstone), 20 (Shale), 21 (Arkose), 22 (Conglomerate) b. 23 (Travertine), 24 (Limestone) c. all of them (19-24) d. none of them

19 (Sandstone), 20 (Shale), 21 (Arkose), 22 (Conglomerate)

6. According to the definitions in the text and your observations, how many of the sedimentary samples are sandstones? a. 2 b. 1 c. 3 d. 4

2

11. What type of cleavage does feldspar have? a. 1 direction b. 2 directions at 90 degrees c. 2 directions , not at 90 degrees d. no cleavage

2 directions at 90 degrees

13. What type of cleavage does hornblende have? a. 1 direction b. 2 directions at 90 degrees c. 2 directions, not at 90 degrees d. no cleavage

2 directions, not at 90 degrees

4. What type of cleavage does feldspar have? a. 1 plane b. 2 planes at 90 degrees c. 2 planes, not at 90 degrees d. 3 planes e. no cleavage

2 planes at 90 degrees

5. Calcite has a hardness of: a. 1 b. 2-3 c. 4 d. 5-6 e. 7

2-3

12. The most likely parent rock for Slate (sample 14) in our collection is: a. 20 (Shale) b. 11 (Fine-Grained Granite) c. 19 (Sandstone) d. 9 (Basalt)

20 (Shale)

2. The most likely parent rock in our collection of Marble (sample 18) is: a. 24 b. 22 c. 10 d. 9

24 (Limestone)

10. What type of cleavage does calcite have? a. 3 directions, NOT at 90 degrees b. 3 directions at 90 degrees c. 2 directions, NOT at 90 degrees d. one direction

3 directions, NOT at 90 degrees

7. Potassium feldspar has a hardness of: a. 1 b. 2-3 c. 4 d. 5-6 e. 7

5-6

2. Quartz has a hardness of: a. 1 b. 2-3 c. 4 d. 5-6 e. 7

7

What is a delta?

A delta is a triangular landform created where a stream enters a body of water and deposits sediment.

What is required to generate an igneous rock with a fine-grained texture?

A fine-grained texture is the product of rapid cooling and crystallization of lava.

What is an accessory mineral?

A mineral that makes up a relatively small portion of the total rock composition

Which of the following is necessary for the formation of slot canyons?

A relatively youthful environment

What causes the same mineral to occur in varieties that are different colors? a. The amount and quality of light reflected off the surface differs in the same mineral. b. Chemical bonds are rearranged in the same mineral. c. The crystalline structure often exhibits differences in shape. d. The ability to transmit light varies in the same mineral. e. A small amount of impurities in the crystal structure.

A small amount of impurities in the crystal structure.

What is the rock name of an intermediate rock with two distinct grain sizes?

Andesite porphyry

Name the hardest and softest mineral on the Moh's scale.

Diamond (hardest) and talc (softest)

In what type of environment was the oyster bed deposited?

Area of brackish water

An item that is solid like a mineral, has definite chemical composition, and shows distinctive physical properties, but is not naturally occurring.

Dinner Plate

Why is the monolith El Capitan in Yosemite National Park more resistant to erosion than other igneous plutons in the park?

El Capitan is unfractured.

cleavage in two directions at 90° angles.

Feldspar

What minerals make up half of Earth's crust?

Feldspars

cleavage in four directions.

Fluorite

What is one feature of the Vishnu Schist caused by differential pressure?

Folding

Which of the following is the best description of the Vishnu Schist? a. Foliated metamorphic rock b. Non-foliated metamorphic rock c. Multi-layered sedimentary rock d. Intrusive igneous rock

Foliated metamorphic rock

You have found a mafic rock with a phaneritic texture. What is a potential rock name?

Gabbro

An item that is solid like a mineral, has definite chemical composition, and shows distinctive physical properties, but does not have an orderly crystalline structure.

Glass

Why glass is not considered a mineral?

Glass has a disorderly atomic structure.

What kind of rock is found in Yosemite National Park? a. Granite b. Gabbro c. Basalt d. Rhyolite

Granite

Which of the following best describes the difference between granite and rhyolite?

Granite is phaneritic and rhyolite is aphanitic.

A mineral consisting of a poisonous gas ionically bonded to an extremely reactive metal.

Halite

cleavage in three directions at 90° angles.

Halite

What kind of depositional environment does the Tapeats Sandstone indicate?

Beach

1. How are Fine-Grained Granite (samples 11) and Gneiss (sample 16) similar? a. Both contain quartz and potassium feldspar b. Both have a "glittery" appearance from mica minerals c. Both samples are the same category of rock d. Both samples are foliated

Both contain quartz and potassium feldspar

What is a roof pendant?

older rock capping the batholith. This rock would have been the roof of the magma chamber.

Ultramafic rocks contain __________ and are commonly found in __________.

olivine; mantle

Muscovite mica has cleavage in _____ direction(s). a. one b. two c. three d. none

one

__________ SiO4 4- tetrahedra join with __________ ions to produce the mineral olivine in the rock peridotite.

Independent; Mg2+ and Fe2+

________ cement produces bright-red and yellow colors in some sandstone. a. Clay b. Calcite c. Quartz d. Iron oxide

Iron Oxide

8. Which mineral in our collection is not in the silicate mineral group? a. calcite b. quartz c. hornblende d. mica e. potassium feldspar

Calcite

What mineral is not scratched by a fingernail, but is scratched by a copper penny?

Calcite

cleavage in three directions not at 90° angles.

Calcite

In what kind of environment was the Bright Angel Shale deposited?

Calm water

Since color is not a very useful way to identify a mineral, what other optical property or properties can be used?

Luster and streak

Which of the following is true about mafic igneous rocks?

Mafic igneous rocks are rich in Fe, Mg, and Ca.

A scientist creates diamonds using high-pressure laboratory experiments. These diamonds are not considered minerals because which of the following requirements has been violated?

Minerals must occur naturally.

12. Measure the size of the crystals in Pegmatite (sample 12). IF they are larger than 1 CM in diameter, the texture of this rock would be considered: a. pegmatitic b. fine-grained c. porphyritic d. glassy

pegmatitic

cleavage in one direction

Muscovite

How will foliation in continental metamorphic rocks formed during subduction be oriented?

perpendicular to the direction of plate movement

A(n) ________ texture would be most UNLIKELY to occur in an extrusive igneous rock. a. pyroclastic b. glassy c. aphanitic d. phaneritic

phaneritic

What are the large crystals visible in this figure, and what do they indicate about the rock they formed in?

phenocrysts; precipitated out as magma cooled

14. The pink mineral visible in Conglomerate (sample 22) is most likely: a. potassium feldspar b. biotite c. hornblende d. calcite

potassium feldspar

Which the following denotes positively charged nuclear particles? a. protons b. electrons c. isotrons d. neutrons

protons

Atoms of the same element always have the same number of ________. a. electrons in the nucleus b. protons in the nucleus c. neutrons in the outer nuclear shell d. electrons in the valence bond level

protons in the nucleus

16. What is the predominant mineral in Sandstone (sample 19)? a. quartz b. hornblende c. calcite d. olivine

quartz

20. What is the predominant mineral found in Quartzite (sample #15)? a. quartz b. feldspar c. calcite d. Muscovite

quartz

11. The non-geologists who wrote the list of contents for our collection called sample #11 "Fine-grained Granite". According to what you have learned in this chapter, is this an accurate description of a granite? a. NO, because the crystals in the sample are visible to the naked eye. It is coarse-grained. b. Yes, there are many examples of fine-grained granite. c. No, because granite is not classified by texture, only by mineral composition. d. It is not possible to determine this without putting the sample under a microscope.

NO, because the crystals in the sample are visible to the naked eye. It is coarse-grained.

What are the two most abundant elements in Earth's crust?

Oxygen and silicon

Which of the following textures describes an igneous rock with anomalously large crystals?

Pegmatitic

Phenocrysts of quartz and feldspar found in some parts of the walls of the Owens River Gorge indicate the lava has what kind of texture? a. Porphyritic b. Phaneritic c. Aphanitic d. Glassy

Porphyritic

Which of the following textures indicates two stages of cooling and crystallization?

Porphyritic

How are metamorphic rocks formed?

Preexisting rock is altered through heat and pressure.

What type of texture does the Bishop Tuff exhibit?

Pyroclastic

A silicate mineral which has silicon-oxygen tetrahedra bonded in single-chained formation along with iron or magnesium atoms.

Pyroxene

___________ silicate mineral consisting solely of silicon and oxygen, with silicon-oxygen tetrahedra bonded in a complex three-dimensional network.

Quartz

In what type of environment was the fine-grained sandstone deposited?

River System

From the following choices, identify the grade of metamorphism and one characteristic mineral associated with each of the metamorphic rocks.

Schist - Intermediate-grade metamorphism - Garnet Slate - Low-grade metamorphism - Chlorite Gneiss - High-grade metamorphism - Sillimanite

During the time that the Dakota Formation was deposited, what was happening to sea level?

Sea level was rising

The Tonto Group, which goes from sandstone to shale to limestone, most likely represents a period of_____________

Sea-level rise

In what type of environment was the coal seam deposited?

Swamp

5. According to the chart in the text, which metamorphic rock has the finest grain size? a. slate b. gneiss c. marble d. phyllite

slate

According to the chart in the text, which rock has the finest grain size? a. slate b. gneiss c. marble d. phyllite

slate

During metamorphism, what is the major effect of chemically active fluids? a. They increase the pressures in deeply buried, regional-metamorphic zones. b. They aid in the movement of dissolved silicate constituents and facilitate growth of the mineral grains. c. They prevent partial melting so solid rocks can undergo very high temperature regional metamorphism. d. They facilitate the formation of schistosity and gneissic banding in hornfels and slates.

They aid in the movement of dissolved silicate constituents and facilitate the growth of the mineral grains.

How is the Owens River Gorge similar to the nearby Sierra Nevada mountain range?

They are both composed of material of similar mineral composition.

What do pumice and scoria have in common?

They both exhibit a vesicular texture.

Which one of the following is not true for minerals? a. They have a specific, internal, crystalline structure. b. They can be a liquid, solid, or glass. c. They have a specific, predictable chemical composition. d. They can be identified by characteristic physical properties.

They can be a liquid, solid, or glass.

Calcite is the main mineral constituent of the sedimentary rock limestone and of the metamorphic rock marble. a. True b. False

True

Olivine is an important mineral in dark-colored igneous rocks. a. True b. False

True

Plutonic rocks are intrusive and generally consist of mineral grains coarse enough to be readily visible in a hand sample. a. True b. False

True

A rock composed of nonmineral matter

Coal

Suppose you found a mineral crystal that looked like topaz. What two minerals could you use in a scratch test to help determine if the mineral is indeed topaz?

Corundum and quartz

What are the two important processes involved in lithification of sedimentary rocks?

Cementation and compaction

How do sheet joints and exfoliation domes form in granite plutons?

Confining pressure on the plutons is removed through erosion of surrounding rock. Plutons then expand.

What are the two most important driving forces of metamorphism?

High heat and pressure

cleavage in two directions not at 90° angles.

Hornblende

Intrusive and extrusive igneous rocks are classified based on what criteria?

How quickly the molten rock cools and crystallizes, and where this occurs with respect to Earth's surface

How are igneous rocks formed?

Igneous rocks are formed by the cooling and crystallization of molten rock.

Natural gas cannot flow out of some shale deposits naturally when the rock has low permeability. In this situation, a method called hydraulic fracturing can be used to extract natural gas. Shale is shattered by pumping fluids (water + chemicals + sand) into the gas-bearing shale unit. The pressure from the incoming fluid fractures the shale, sand grains prop the fractures open as the fluid is then pumped out of the ground, and then the gas can flow freely. Hydraulic fracturing, also called "fracking," is controversial because: preexisting faults can be reactivated, which can cause small-sized earthquakes; chemicals in the injected fluids can get into groundwater that is used for drinking water; and the wastewater is environmentally hazardous and can leak into soils; etc. Most of the wastewater produced by fracking is pumped back to the surface where it is stored in artificial ponds. Wastewater is diluted with fresh water and pumped back into the ground to shatter more shale. After several uses, the water can no longer be used and is sent to specialized treatment facilities. This process uses millions of gallons of fresh water each year, often in regions where water availability is already a problem. Select all statements that apply to the process of hydraulic fracturing, or "fracking."

Hydraulic fracturing allows geologists to capture natural gas stored in the pore spaces of shale Hydraulic fracturing threatens the supply of other natural resources.

What is the basic foundation of Moh's hardness scale?

If a mineral scratches an object, then the mineral is harder than the object.

Minerals are fundamental components of rocks and have great economic and commercial significance to humans. Therefore, geologists need a set of characteristics to identify and describe what makes an object a mineral versus something synthetic (such as plastic, for example). The criteria that defines matter as a mineral is that it is inorganic, composed of an orderly crystalline structure, solid, naturally occurring, and can be expressed by a chemical formula. Some matter looks very similar to minerals, but does not quite meet the criteria. For example, consider glass and quartz. Both are transparent and can have similar appearance. Glass does not have an orderly internal structure; its silica atoms are randomly arranged. Thus it is not a mineral. Quartz, however, has an organized chemical structure of silica atoms, each surrounded by four oxygen atoms and is a mineral. In the list below, indicate which of the items are minerals. Seawater Charcoal Synthetic diamonds Quartz Amber Granite Gold nugget

Quartz , Gold nugget

An important reason that sedimentary rocks are economical is that they are porous and permeable. Natural gas, for example, collects in the pore spaces between the sediment grains within these rocks. Porosity is the amount of space between the grains within a rock. It can be quantified as the total volume of space between grains divided by the volume of grains. A low porosity means that there is little space, and a high porosity means that there is a lot of space. Permeability is how much the pore spaces are connected. Fluid flows through rocks that are more permeable. The image below is an illustration of two different rocks. These images are magnified to show the individual grains (dark gray) and pore spaces (light gray) that make up the rock. Study these images and select the statement that describes the correct comparison of the porosity and permeability of these two rocks.

Rock A has a lower porosity and a lower permeability than Rock B.

What does it mean if an igneous rock has an aphanitic texture?

The igneous rock exhibits mineral crystals too small to see with the naked eye.

Everything is made of atoms. Atoms are the particles that make up minerals (and all elements). Each atom is composed of protons and neutrons at its center, or nucleus, and electrons, which surround the nucleus. Electrons have very little density and a charge of −1. Protons have higher density and a charge of +1. With the same number of electrons and protons, an atom is electrically neutral—it has no electrical charge. Neutrons have the same density as protons and no electrical charge. The atomic number, shown in the key in the periodic table of elements below, represents the number of protons in an atom. This determines an atom's chemical and physical characteristics as well as which chemical element it is; elements with similar properties are arranged in columns (groups) below. The mass number, which is the atomic weight of an element rounded up, is equal to the number of protons plus the number of neutrons in an atom. There can be several variations of a chemical element, which are known as isotopes. While an element maintains the same number of protons, the number of neutrons differs between isotopes. Refer to the periodic table of the elements to help you answer this question. If the number of protons in an electrically neutral atom is 92 and its mass number is 238, what is the name of that element, its number of electrons, and number of neutrons? a. Uranium, 92 electrons and 92 neutrons b. Uranium, 146 electrons and 238 neutrons c. Uranium, 92 electrons and 146 neutrons d. Uranium, 146 electrons and 92 neutrons

Uranium, 92 electrons and 146 neutrons