Geology1301
Porosity and Permeability of Sedimentary Rocks
Rock A has a lower porosity and a lower permeability than Rock B
What is a renewable resource?
One that can be replenished quickly as it is used.
For a geologist, the most important characteristic of a sedimentary rock is its ________.
layering
Obsidian exhibits a ________ texture.
glassy
Where else might you expect to find metamorphic rocks like the Vishnu Schist of the Grand Canyon?
*In a mountain range. *Deep beneath Earth's surface, where sedimentary layers have been buried.
What does the Vishnu Schist tell you about the history of the Grand Canyon prior to the formation of the canyon itself? What is the order of events in the Grand Canyon? Place the following events in the order in which they happened.
1.) Formation of Vishnu Schist 2.) Deposition of sedimentary layers found above the Vishnu Schist 3.) Carving of the canyon by the Colorado River
Rank from youngest = 1 (most recent) to oldest = 4.
1.) Intrusion of light colored igneous rock 2.) Metamorphism of rock that became the dark colored metamorphic 3.) Lithification (the creation of sedimentary rock) from sediment 4.) Deposition of Sediments
At what age can children work in the mines of Cerro Rico?
14
How much money does Omar earn mining at Cerro Rico?
30 US dollars a week
What is the average lifespan of a Cerro Rico miner?
40 years old
Which of the following is a characteristic of a conglomerate?
A conglomerate is made up of course grains that are poorly sorted.
The NEBULAR THEORY is the most widely accepted view of the origin of our solar system. Which of the following is a short description of the nebular theory?
A large cloud of space gas and dust condensed and contracted to form a rotating disk with a star formed at the center. Repeated collisions caused bodies to coalesce, leading to the current configuration of our solar system.
What is an accessory mineral?
A mineral that makes up a relatively small portion of the total rock composition
What is the D" layer?
A partially molten layer above the outer core at the base of the mantle.
What causes the same mineral to occur in varieties that are different colors?
A small amount of impurities in the crystal structure.
What main characteristics are used to distinguish the two types of mountain belts?
Age and degree of erosion
What is the rock name of an intermediate rock with two distinct grain sizes?
Andesite porphyry
What causes a lack of cleavage in some minerals?
Bonds of equal strength in all directions
Which of the following correctly states the order in which major features of North America were formed?
Canadian Shield, Appalachians, North American Cordillera
What are the two important processes involved in lithification of sedimentary rocks?
Cementation and compaction
The layers of Earth are based on what two sets of characteristics?
Chemical composition and physical properties
Which of the following best describes the term cleavage?
Cleavage is the splitting of minerals along natural planes of weakness.
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.
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
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.
What are the two most important driving forces of metamorphism?
High heat and pressure
You have found a mafic rock with a phaneritic texture. What is a potential rock name?
Gabbro
Which of the following exhibits three sets of cleavage at 90° angles?
Galena
Why are garnets used in sandpaper?
Garnets have a value of 8 or 9 on the Mohs Hardness Scale, making them very abrasive.
Why glass is not considered a mineral?
Glass has a disorderly atomic structure.
Which of the following best describes the difference between granite and rhyolite?
Granite is phaneritic and rhyolite is aphanitic.
How does gypsum form?
Gypsum forms from evaporation of shallow seas by a chemical process.
Return to the Gigapan image. Closely examine the rocks for evidence of metamorphic agents. Determine the metamorphic agent(s), or main metamorphic process(es), of the dark metamorphic rock in the Gigapan image.
Heating and pressure in one main direction
Select all statements that apply to the process of hydraulic fracturing, or "fracking."
Hydraulic fracturing threatens the supply of other natural resources. Hydraulic fracturing allows geologists to capture natural gas stored in the pore spaces of shale.
What is the basic foundation of Moh's hardness scale?
If a mineral scratches an object, then the mineral is harder than the object.
Which of the following best defines a mineral and a rock?
In a mineral the constituent atoms are bonded in a regular, repetitive, internal structure; a rock is a lithified or consolidated aggregate of different mineral grains.
Examine the images of the Grand Canyon below. Notice that most of the canyon consists of layers of sedimentary rocks, but if you were to hike down into the inner gorge you would encounter the Vishnu Schist, a metamorphic rock. Which of the following processes were involved as the Vishnu Schist metamorphosed?
Intense pressure due to regional metamorphism.
_____ igneous rocks are those that cool below the surface.
Intrusive
What is the difference between "magma" and "lava"?
It is just a name change, and lava is what magma is called if it reaches the surface of Earth.
Which of the following is true about mafic igneous rocks?
Mafic igneous rocks are rich in Fe, Mg, and Ca.
What is the difference between magma and lava?
Magma is molten rock located below the surface; lava is molten rock erupted above ground.
Two of these statements are true of conglomerate sedimentary rock similar to the one shown in the Gigapan image. Select the two correct statements.
Many of the clasts in this rock have rounded edges. & Many of the clasts within this rock are larger than sand.
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?
Metamorphic and sedimentary
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.
Based on the diagram shown in the video, name two minerals that are unlikely to coexist in the same igneous rock.
Muscovite and pyroxene
Could metamorphic rocks reach the surface of a planet without rock-uplifting processes?
No, metamorphic rocks must be uplifted and exposed by erosion.
Throughout its history, how many people are estimated to have died from mining accidents and mining-related illnesses due to working underground at Cerro Rico?
Over 8 Million
Which of the following textures describes an igneous rock with anomalously large crystals?
Pegmatitic
Which of the following textures indicates two stages of cooling and crystallization?
Porphyritic
In the list below, indicate which of the items are minerals.
Quartz & Gold Nugget
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
Choose the most likely scenario for how this rock formed. You can infer the environmental conditions where the rock formed from the characteristics of the clasts. For example, in places where sediments are affected by high-energy waves or wind, clasts will be weathered to a similar size and thus will be well sorted. In places with quiet, calm water, small clasts like mud are most likely to accumulate in thin layers.
Rocks eroded from mountains were deposited over a short time in a dry environment, where they were buried by other sediments and cemented into rock.
Which of the following terms is associated with the three main rock groupings? Select all that apply
Sedimentary Igneous Metamorphic
What is a nonrenewable resource?
Something that cannot be easily replaced in our lifetime.
Why are the sedimentary layers at Capitol Reef tilted?
The Laramide Orogeny is responsible for tipping the strata on their sides.
What object or class of objects makes up most of the solar system's MASS?
The Sun
Which of the following best describes why the Vishnu Schist is visible at Earth's surface?
The Vishnu Schist was exposed when sedimentary layers above it were eroded.
The upper mantle can be divided into the asthenosphere and lithosphere based on what physical properties?
The asthenosphere is solid, but mobile, while the lithosphere is solid and relatively rigid.
What happens to the atmosphere as you move away from Earth's surface?
The atmosphere thins.
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.
By what process did the gabbro turn into amphibolite?
The gabbro was heated to 500 °C and buried a few miles below the Earth's surface.
The enormous cloud of gas and dust initially condensed due to particle attraction. What force then pulled the cloud into a flat disk shape?
The inward pull of gravity.
What mineral is the hardest known substance in nature?
diamonds
Which of the following is a likely explanation for why there is limestone near the summit of Mount Everest, the tallest mountain on Earth?
The limestone found at the top of Mt Everest was formed in an ocean
This Gigapan image shows a dark metamorphic rock in contact with a lighter igneous rock (granite). Review the statements below, and determine which are correct about the dark metamorphic rock on the left in the Gigapan image.
The metamorphic rock shows foliation. The metamorphic rock has undergone high-grade metamorphism.
What does an igneous rock with a pyroclastic texture tell a geologist?
The rock was likely formed by a violent volcanic eruption.
If stable platforms represent sedimentary rocks that cover continental shields, then what statement must be true?
The sedimentary rock atop the stable platforms must be younger than continental shields.
Which of the following best describes mineral habit?
The shape a mineral grows into, given sufficient space.
What do pumice and scoria have in common?
They both exhibit a vesicular texture.
Which one of the following is not true for minerals?
They can be a liquid, solid, or gas.
Which statement accurately describes continental shields?
Very old, stable regions composed of igneous and metamorphic rocks
Which of the following describes a texture containing bubble-shaped cavities?
Vesicular
What role does hot ion-rich water play in the process of metamorphism?
Water migrates into host rock carrying ions to stable minerals in order to facilitate growth of new metamorphic minerals.
What is a roof pendant?
a V-shaped valley formed by stream processes
finding protons and neutrons
atomic number minus atomic weight (mass)
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
Why does magma rise toward Earth's surface?
because it is less dense than the material around it
Where do most metamorphic rocks form?
between a few and many kilometers beneath Earth's surface
Limestone is formed primarily through ________.
biochemical sediments secreted by marine organisms
A major difference between coal and oil/gas is ________.
coal forms in swamps and oil/gas form in marine environments
Which mineral reacts readily with cool, dilute hydrochloric acid to produce visible bubbles of carbon dioxide gas?
calcite
Quartz exhibits __________.
conchoidal fracture
The major role of thermal energy (heat) in metamorphism is ________.
driving chemical reactions that lead to recrystallization
Metamorphism occurs when a rock ________.
experiences conditions that are significantly different from those that formed the rock
Through the course of time, bodies in our solar system have become __________ and __________ due to collisions.
fewer in number; larger in size
Shield areas in continental interiors are characterized by _________?
flat areas that include rocks older than 1 billion years old
Chemically active fluids are?
fluids that readily change to gases at the surface
Coal beds originate in ________.
freshwater coastal swamps and bogs
Which environment of deposition is NOT represented by the rocks in Capitol Reef National Park?
glacial
What kind of metamorphic texture results in the segregation of light and dark mineral bands?
gneissic texture
Igneous rocks of felsic composition have __________ and __________ relative to mafic igneous rocks.
greater silica; lower melting temperature
The resistance of a mineral to abrasion is known as ________.
hardness
Granite and gabbro ________.
have a similar texture
What is a mantle plume?
hot mantle rock rising from deep within the Earth
Which of the following is a mineral?
ice
What is one way a glassy texture forms?
lava cools rapidly
The most abundant chemical sedimentary rock is _______.
limestone
The amount or quality of light that is reflected from a mineral surface is known as __________?
luster
Which of the following describes the light reflecting and transmission characteristics of a mineral?
luster
The common rock produced by the metamorphism of limestone is ________.
marble
Which two rock types would you expect to see sitting next to each other after a very long period characterized by only uplift and erosion?
metamorphic and sedimentary rocks
Environmental science primarily focuses on any of the following except ________.
mineral classification
Regardless of their size, most rocks are made up of __________.
minerals
What are the two types of crust?
oceanic and continental
What is the most common place for sediment to be deposited?
oceans
Ultramafic rocks contain __________ and are commonly found in __________.
olivine; mantle
Detrital sedimentary rocks are typically classified on the basis of their ________.
particle size
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
What theory dramatically improved geologist's ability to predict where certain ore deposits were formed?
plate tectonics
Hardness describes a mineral's __________.
resistance to being scratched
When sand lithifies, the resulting rock is commonly called ________.
sandstone
Which of the following is not a fundamental particle found in atoms?
selectron
What is the primary type of mining that takes place under the Bolivian mountain, Cerro Rico?
silver
Which of the following is evidence of glaciation in Yosemite National Park?
striations in granite & U-shaped valleys
A scientific ________ is a tentative or untested explanation that is proposed to explain scientific observations.
theory
Why are boulders not a mineral?
they do not have a well-defined chemical composition
How do metamorphic rocks reach Earth's surface?
through removal of overlying rocks
The primary goal of Earth Science is ________.
to identify the patterns in nature and use that information to predict the future
Hornblende has _____ cleavage planes at _____ angles.
two; non-90°
If magma or lava cools quickly, the resulting igneous rock will have ________.
very small crystals
The first step in turning a rock into a sediment is ________.
weathering alters the rock
What does the term aeolian mean?
wind-borne origin