Geology 101 Midterm Flashcards
The study of the origin and structure of the universe is known as
cosmology
During the formation of the early universe, what is thought to have occurred first?
hydrogen formed from subatomic particles
What features would you expect to find in a differentiated planet?
internal layers with unique physical and chemical properties
Compared to oceanic crust, continental crust is
thicker and less dense
If we labeled the Earth’s interior in sections 1 to 5, with 5 being the most internal section, which number would identify a liquid portion of the Earth’s interior?
4 (outer core) - Earth has a liquid outer core and solid inner core
If we labeled the Earth’s interior in sections 1 to 5, with 5 being the most internal section, which layers would make up the lithosphere?
1, 2, and part of 3 (continental, oceanic, and uppermost mantle)
The Moho boundary marks the division between the
crust and mantle
A single, unbroken plate can be made up of both oceanic and continental crust. (True/False)
True
According to the text, the moon is thought to have formed when a small planet collided with the Earth. (True/False)
True
Conchoidal, earthy and uneven are all terms that refer to
fractures
A substance with a specific gravity of 0.9 is dropped into a beaker of water. The substance will
float
double refraction
an image viewed through a thin slice appears in double
A mineral that bends and returns to its original shape is called
elastic (think Elastagirl)
To be considered a mineral, atoms must meet 4 criteria
naturally occurring, crystalline solid, inorganic, specific chemical composition
Is naturally occurring ice a mineral?
Yes
Is diamond formed in a laboratory a mineral?
No
Is calcite a mineral?
Yes
Is quartz a mineral?
Yes
If a material contains carbon, it cannot be a mineral. (True/False)
False
What kind of mineral is SrSO4?
sulfate
What does crystal habit refer to?
the shape of a crystal as it grows
Which term refers to the formation of a mineral from a melt?
solidification
When oil is pumped from deep wells, hot water is typically pumped with it. As the water cools in the well pipes, barite will often precipitate onto the pipe walls, eventually ruining the pipes. What type of mineral is barite?
sedimentary
What is lithification?
processes that turn sediments into rock
label the rock cycle:
1 -uplift -> 2 3 -heat, pressure-> 4 1
- igneous
- erosion
- sedimentary
- metamorphic
extrusive igneous rocks
magma extruded to the surface (lava) and solidified on the ground
You are most likely to find metamorphism near a
sill
felsic minerals
quartz, muscovite, potassium feldspar, biotite, amphibole
gabbro is an
intrusive mafic rock
basalt is an
extrusive mafic rock
rhyolite is an
extrusive felsic rock
What is a pegmatite?
igneous rock with extremely large crystals
What is most likely to happen in a well mixed, mafic magma as it cools?
crystallized olivine will react with the magma and convert into pyroxene
Which mineral melts at the lowest temperature?
(a) Na-feldspar (b) Ca-feldspar
(c) olivine (d) quartz
(d) quartz
Which could be a tuff?
(a) rhyolite (b) peridotite (c) granite (d) granodiorite
(a) rhyolite
Which is a type of volcanic glass?
(a) peridotite (b) pumice (c) porphyry (d) phenocryst
(b) pumice
Which combination of magma + gas content leads to the most explosive volcanic eruptions?
felsic + high
Which combination of magma + gas content would you expect to be the most viscous?
felsic + low
Which combination of magma + gas content would be most likely to form pahoehoe?
mafic + high
Most of the earth’s volcanoes are
basaltic
Pyroclastic debris the size of a US quarter are best classified as
lapilli
Example of a shield volcano
Mauna Loa and Mauna Kea, Hawaii
Which describes the formation of a caldera?
massive collapse of the mountain into a depleted magma chamber
lahar
refers to a mudflow of hot ash and water
How do volcanologists know an eruption is about to happen?
earthquakes, ground deformation (tilt & expansion), water/ground temperature changes, changes in gas emissions (such as SO2 or HCl)
Most of the minerals and particles found in sediments ultimately came from
previously existing rocks
Addition of which ion makes water more acidic?
H+
Which mineral dissolves congruently?
(a) quartz (b) Na-feldspar (c) olivine (d) pyroxene
(d) pyroxene
4FeSiO3 + O2 + 8H2O = 2Fe2O3 + 4H4SiO4o is an example of
incongruent weathering
What is most likely to be found in a soil for B-horizon?
caliche
Which climate typically produces the best soil for agriculture?
temperate
What does a mixture of sand, silt, and clay need to become a soil?
humus
What is ice (or frost) wedging?
fracturing caused by expanding ice in a crack
Quartz minerals found in an ancient sand deposit are found to be etched, or frosted on the surface of each grain. The deposit was most likely a
desert sand dune
What is a synonym of clastic?
detrital
CaCO3 precipitating as calcite could begin to precipitate as aragonite if the water temperature is increased (True/False)
True
According to the textbook, additions and removals of dissolved solids in the ocean are
balanced: the modern ocean’s salinity is approximately constant
Iron is dissolved in water. If the solution is in contact with the atmosphere, what mineral is most likely to precipitate?
Fe2O3 (hematite)
What are reefs made from?
colonies of single celled organisms
Which is primarily a chemical sedimentary environment?
conglomerate
What type of sedimentary rock is most likely to develop from a swamp environment?
coal
What type of metamorphism are you most likely to find at a mid-ocean ridge?
hydrothermal
burial metamorphism is likely with
low temperature & low pressure
volcanism would likely produce metamorphism with
high temperature & low pressure
Metamorphic conversion of graphite to diamond is an example of
structural rearrangement
Order gneiss, phyllite, schist, and slate from low to high grade metamorphism
slate, phyllite, schist, and gneiss
A metamorphic rock is altered at a high temperature and pressure, and then later re- metamorphosed at a much lower temperature and pressure. This phenomenon is known as
retrograde metamorphism
A rock is found to contain chlorite and albite - what type of rock is it?
low grade metamorphic rock
A streched-pebble conglomerate is an example of
deformational texture
