Geol Unit 3
Chemical sedimentary rocks form from materials ________.
carried in solution
Atoms that share electrons have a(n) ________ bond.
covalent
Detrital sedimentary rocks are typically classified on the basis of their ________.
particle size
________ is the primary basis for distinguishing among various detrital sedimentary rocks.
particle size
Which two elements combine to make most of the common rock forming minerals in the crust?
silicon and oxygen
When Calcium (Ca) bonds with oxygen, it gives up two electrons. What is the charge of the Ca ion in this compound?
+2
An atom's mass number is 13 and its atomic number is 6. How many neutrons are in its nucleus?
7
Carbonates always include ________.
CO3-2
What is the most common carbonate mineral?
Calcite
Which of the choices correctly describes three types of common cements in sedimentary rocks?
Calcite (which effervesces in dilute acid), silica (which produces the hardest sedimentary rocks), and iron (which gives rocks a reddish color)
Halides always include ________.
Cl-1, F-1, or Br-1
Which of the following resources is created by sedimentary rock forming processes?
Coal
Which of the following resources are all considered nonrenewable?
Coal, oil, and natural gas
Distinguish between regional and contact metamorphism.
Contact metamorphism occurs when magma intrudes existing rock and heats it enough to cause metamorphic changes; regional metamorphism occurs when large quantities of rock are subjected to high heat and pressure during mountain building.
Below is a picture of the enormous Bingham Canyon copper mine in Utah. What is the reason that the mine is so large?
Copper is economically valuable even in small quantities, so it is considered to be worth creating a large hole to extract as much as possible.
Which option correctly describes the difference between a renewable resource and a nonrenewable source?
Corn is a renewable resource; copper is a nonrenewable resource
What happens when atoms form an ionic bond?
Electrons are transferred to form positively and negatively charged atoms.
What is the difference between extrusive igneous rocks and intrusive igneous rocks?
Extrusive igneous rocks cool and solidify on the Earth's surface, whereas intrusive igneous rocks cool and solidify beneath the Earth's surface.
________ is composed of alternating bands of light and dark silicate minerals.
Gneiss
Which of the choices lists the four basic compositional groups of igneous rocks, ranging from the highest silica content to the lowest silica content?
Granitic, andesitic, basaltic, ultramafic
What are the economic uses of three common nonsilicate minerals?
Halite is used for common salt, gypsum is used in plaster, and graphite was used as pencil lead.
In what situation is hydraulic fracturing used?
Hydraulic fracturing is used to open cracks in impermeable rocks so that the natural gas can flow into wells.
What are hydrothermal deposits, and what are the two general types?
Hydrothermal deposits are deposits of ore generated from hot, ion-rich fluids. The two main types of hydrothermal deposits are vein deposits and disseminated deposits.
Element 20, Ca, has what chemical property?
It behaves as a metal ion, giving up two electrons to form a +2 ion.
What is required for an igneous rock to weather?
It must be exposed at the surface of Earth.
How does magma differ from lava?
Magma exists strictly below Earth's surface, whereas lava is found on Earth's surface.
Which of the following is characteristic of metals? Choose all that apply.
Metals can be hammered into thin sheets. Metals can be drawn into thin wires. Metals are good conductors of electricity.
The basic building blocks for halite are ________ and ________.
Na; Cl
Which of the following are fossil fuels? Choose all that apply.
Natural gas Coal Oil
How does a mineral resource differ from an ore deposit?
Ore deposits are concentrations of metal, whereas mineral resources do not contain metals.
What are the eight most common elements found in Earth's crust, listed from most common to least common (by percentage)?
Oxygen, silicon, aluminum, iron, calcium, sodium, potassium, magnesium
Which are the two most common minerals in detrital rocks?
Quartz and feldspar
Sulfates always include ________.
SO4-2
How might a mineral deposit that previously could not be mined profitably be upgraded to an ore deposit?
The demand for the mineral increases, raising its value.
The minerals gold, silver and mercury are often found in ________.
The minerals gold, silver and mercury are often found in ________.
What does a porphyritic texture indicate about the cooling history of an igneous rock?
The rock began cooling under the Earth's surface, but then was moved to above the Earth's surface where it finished cooling.
Which one of the following is not true for minerals?
They can be a liquid, solid, or gas.
What is the particular significance of valence electrons?
Valence electrons form chemical bonds between atoms by being transferred or shared.
When is a rock considered an ore? Choose all that apply.
When it contains at least one metallic mineral in sufficient amounts to be extracted profitably When it contains fluorite or sulfur minerals in sufficient amounts to be extracted profitably
Clay is an example of ________.
a silicate that forms from weathering of other silicates
Diamond and graphite are both minerals composed of ________.
a single element
Which of the following changes may occur during metamorphism?
all of the above
What are the smallest particles of matter that exhibit and define the distinctive chemical characteristics of the individual elements?
atoms
Why does magma rise toward Earth's surface?
because it is less dense than the material around it
Limestone is formed primarily through ________.
biochemical sediments secreted by marine organisms
An element's atomic mass is defined by the number of ________ in the nucleus.
both protons and neutrons
The change from a sediment to a sedimentary rock typically involves ________.
burying the sediment
Although it is relatively common, limestone is an economically important rock type because its major constituent mineral, ________, is used in the production of ________.
calcite; cement
Which of the following pairs are likely products of weathering granite?
clay and quartz
A major difference between coal and oil/gas is ________.
coal forms in swamps and oil/gas form in marine environments
What mineral is the hardest known substance in nature?
diamond
The octet rule states that atoms tend to gain, lose, or share electrons until they are surrounded by ________ valence electrons.
eight
Which of the following best describes bedded gypsum and rock salt?
evaporates; chemical, sedimentary rocks
Death Valley is a site where ________ sedimentary rocks are common.
evaporite
The most common group of silicates is ________.
feldspar
Which of the following minerals is a silicate?
feldspar
Coal beds originate in ________.
freshwater coastal swamps and bogs
Silicates most commonly form ________.
from cooling molten rock
Which one of the following is not related to chemical weathering?
frost wedgingdecomposition
Quartz can be found in ________.
glass
Obsidian exhibits a ________ texture.
glassy
Select from the list below the coarse-grained rock that is composed mainly of quartz and potassium feldspar.
granite
Igneous rocks that contain mostly quartz and feldspar with small amounts of biotite would be described as having a(n) ________ composition.
granitic
Which of the following is not a criterion for defining something as a mineral?
hard
Granite and gabbro ________.
have a similar texture
The primary agent of contact metamorphism is ________.
heat
Chemical weathering would be most effective ________.
in a warm, humid climate
Halite and gypsum are ________ minerals.
industrially useful
An igneous rock that cools deep inside Earth is called a(n) ________ igneous rock
intrusive
The bond between sodium (Na) and Chlorine (Cl) to form halite (salt) is a(n) ________ bond.
ionic
Atoms that have an electrical charge due to a gain or loss of electrons are called ________.
ions
Quartz forms at ________ temperature than olivine.
lower
High heat and high pressure (without melting) will lead to ________ rocks.
metamorphic
A naturally occurring concentration of one or more metallic minerals that can be extracted economically is a(n) ________.
ore
Light colored silicates have a specific gravity of about 2.7 grams/cm3 are composed primarily of the silica tetrahedra and ________.
potassium, calcium, sodium, and aluminum
Which the following denotes the positively charged particles in an atom's nucleus?
protons
Atoms of the same element, zinc for example, have the same number of ________
protons in the nucleus
Deposits of which of the following minerals would never be considered an ore due to their relatively low market value?
quartz
Which common mineral is composed entirely of silicon and oxygen?
quartz
Which of the following is not a dark silicate mineral?
quartz
The texture of an igneous rock
records the rock's cooling history
When sand lithifies, the resulting rock is commonly called ________.
sandstone
Most sediment is formed by ________.
settling out of a fluid
Compaction would probably be most significant as a lithification process for ________.
shale
The low grade metamorphism of shale produces ________.
slate
Gypsum, which is widely used in plaster and wallboard, is a member of the ________ group
sulfate
Many metals are extracted from ores that contain ________ minerals.
sulfate
What time span is required to produce most mineral deposits?
tens of thousands to millions of years
The rock began cooling under the Earth's surface, but then was moved to above the Earth's surface where it finished cooling.
texture and mineral composition
Chalk forms from ________.
the hard parts of microscopic organisms that accumulate on the sea floor
The most common group of rock forming minerals is ________.
the silicates
Intrusive igneous rocks are often coarse-grained because ________.
the slow cooling at depth allows large crystals to grow
If magma or lava cools quickly, the resulting igneous rock will have
very small crystals
Which of the following is a renewable resource?
water
