Exam 2 Geology
Which of these conditions could form rocks that are partly metamorphic and partly igneous?
4
Which of the following describes lineation?
All of these describe lineation
Which of the following can occur within a magma chamber?
All of these: Sinking or floating crystals may change the composition of the remaining magma. Wall rocks can melt and become incorporated into the magma. If two magmas mix, the resulting magma would be between the composition of the two magmas.
Determine which type of sedimentary rock this sample is:
Biological (Biochemical)
Determine which type of sedimentary rock this sample is: This rock fizzes in acid.
Chemical
Determine which type of sedimentary rock this sample is:
Detrital (Clastic)
Based on the image and your knowledge of metamorphic minerals, which of the following is true?
Garnet is diagnostic of moderate-to high-grade metamorphic conditions.
The effect of transportation on a pebble's particle size is best summarized by which statement?
Its size decreases.
What is the name of this rock?
Obsidian
What can you infer from this contact between an overlying conglomerate and underlying sandstone?
There was an abrupt event, such as a flood.
Which of the following are ways that viscosity affects gases in magma?
Viscous magma prevents gas from escaping easily.
How does a graded bed form?
a gradual decrease in the strength of the current over time
What kind of metamorphic rock is formed where rocks have been heated but not deformed?
a rock with metamorphic minerals but no foliation or lineation
What chemical processes can occur during metamorphism and deformation?
all of these
Which of the following does NOT match a sedimentary rock with a possible metamorphic equivalent?
all of these are correct matches
Composite volcanoes are so called because they:
are composed of lava flows, pyroclastic material, and mudflows
The large cross beds in these rocks indicate that the sediment was deposited:
by the wind or a water current
Which of the following igneous rocks would be formed by the slowest cooling?
coarse granite
The most dangerous type of volcano is a:
composite volcano
What type of stress formed the structure shown in this figure?
compression
What are the three main types of stress?
compression, tension, shear
When a rock is buried deep in the Earth and experiences the same force from all sides, it is under:
confining pressure
What type of metamorphism would occur in this setting?
contact metamorphism
Name this Sedimentary Rock: ___________
coquina
What is the composition of this rock? (Note: This is an exception to the color rule)
felsic
Which of the following causes magma to be less viscous?
fewer silicate chains in the magma
The deep-sea floor is characterized by sediment dominated by:
fine dust and the remains of single-celled organisms
Which of the following changes in conditions would cause melting of a solid rock?
from A to B
What is the name of this rock?
granite porphyry
Shield volcanoes have low slopes primarily because:
high-viscosity dome-forming eruptions
Under what conditions was this rock likely deformed?
hot and deep conditions
In what environments does high pressure/low temperature metamorphism occur?
in a subduction zone or accretionary prism
The geothermal gradient is the:
increase of the Earth's temperature with increase in depth
An igneous rock that solidifies below the surface is called a(n):
intrusive rock
Volcanic mudflows (lahars) are common on composite volcanoes because:
large amounts of rain and snowmelt mix with loose ash on steep slopes
Name this Sedimentary Rock: ___________ This sample fizzes in acid.
limestone
What is a common rock that can be dissolved by water and weak acids?
limestone
Hot spots in oceanic settings typically produce:
lines or clusters of volcanic islands
Lithifies can be defined as:
loose sediment hardens into sedimentary rock
What is the composition of this rock?
mafic
Which of the following is NOT involved in turning some sediment into sedimentary rock?
metamorphism
Which of the following processes is NOT considered physical weathering?
oxidation
Which of the following weathering processes results in the reddish-orange coating on rocks, in soils, and on metal (rust)?
oxidation
When melting forms magma:
partial melting produces a magma that is more felsic than the source
What is the name of this rock?
porphyritic andesite
Name this Metamorphic Rock
quartzite
The main cause of melting along subduction zones is the:
release of water from the subducting plate
What type of rock would you form in this environment, showing a dried up lake bed?
rock salt and other evaporite minerals
Name this metamorphic rock:
schist
What type of stress formed the structure shown in this figure?
shear
The igneous feature shown in this figure is a:
sill
Name this Sedimentary Rock: ___________ This rock feels like fine sand paper.
silstone
This relatively large, symmetrical volcano contains interlayered lava flow, pyroclastic deposits, and volcanic mudflows. What kind of volcano is it?
stratovolcano (composite)
What type of stress formed the structure shown in this figure?
tension
If a rock is subjected to differential stress, then it means that:
the amount of stress is greater in some directions than in others
What typically happens to the size, shape, and sorting of clasts as they are transported from steep mountains toward more gentle settings?
the clasts become more rounded
Which of the following characteristics are NOT used to classify and name clastic sediments?
the climate in which the clasts are produced
Which of the following is likely to be true about the left volcanic feature compared to the right one in this figure?
the magma probably formed at a higher temperature
Coarsely crystalline igneous textures indicate that:
the rock cooled quickly
A porphyritic igneous texture indicates that:
the rock cooled slowly and then quickly
What is the main difference between conglomerate and breccia?
the shape of the clasts
What is the texture of this rock?
vesicular
The uniformly-sized sand shown here would be described as:
well sorted