GEOLOGY QUIZ NINE
In what site on this figure would you expect high pressure/low temperature metamorphism? A and B B and C C and D D and E none of these
A and B
In which region would you be most likely to find a rock experiencing blueschist metamorphism? C A B D E
C
Which of the following processes cannot occur in the formation of metamorphic rock? Complete re-melting of rock, followed by solidification to form a new rock Realignment of minerals so that they develop a preferred orientation Segregation of minerals into layers of different compositions Solid-state rearrangement of atoms or ions to create a new assemblage of minerals All of these may occur during metamorphism
Complete re-melting of rock, followed by solidification to form a new rock
In the diagram above, if a rock moves from point A to point D, this is likely: Contact metamorphism Lithification Decompression melting Regional metamorphism Blueschist metamorphism
Contact metamorphism
In which region would you be most likely to find a rock experiencing contact metamorphism?
D
In the diagram above, if a rock moves from point A to point C, this is called: Prograde metamorphism Retrograde metamorphism Lithification Decompression melting Contact metamorphism
Prograde metamorphism
Fluids are not an important component of metamorphic reactions during what kind of metamorphism? Retrograde Prograde Blueschist Contact Regional
Retrograde
In the diagram above, if a rock moves from point E to point D, this is called: Retrograde metamorphism Lithification Decompression melting Contact metamorphism Prograde metamorphism
Retrograde metamorphism
Quartzite is a metamorphic rock that forms from a __________ parent. Granite Limestone Sandstone shale
Sandstone
As you are hiking Mt. Shuksun you notice all the rocks around you are foliated with blue minerals. Which of the following deductions is incorrect? These rocks experienced low pressure, low temperature metamorphism This area was once part of a subduction zone These rocks experience high pressure, low temperature metamorphism These rocks have been uplifted by plate tectonics
These rocks experienced low pressure, low temperature metamorphism
In the rock cycle, water can play an important role. How does water affect the formation of metamorphic rocks? Water increases reaction rates Water deposits minerals to cement pieces together Water helps soften rocks Water reduces the melting point Water doesn't affect the formation of metamorphic rocks
Water increases reaction rates
In what site on this figure would you expect high pressure-low temperature metamorphism?
a
In contact metamorphism the source of increased temperature and pressure is _________ . a local intrusive heat source the increase in pressure with increasing depth of burial the increase in temperature with increasing depth of burial due to increased rate of radioactive decay
a local intrusive heat source
Which of the following does NOT match a sedimentary rock with a possible metamorphic equivalent? sandstone-quartzite limestone-marble shale-schist shale-gneiss all of these are correct matches
all of these are correct matches
In what site on this figure would you expect low pressure/high temperature metamorphism?
c
In what site on this figure would you expect regional metamorphism?
d and e
Which of the following rocks represents the highest metamorphic grade? slate schist phyllite gneiss
gneiss
Which of the following lists is arranged in order from highest to lowest grade of metamorphic rock? slate, phyllite, schist, gneiss slate, gneiss, phyllite, schist gneiss, schist, phyllite, slate gneiss, slate, schist, phyllite
gneiss, schist, phyllite, slate
In what environments does high pressure/low temperature metamorphism occur? near magma but at shallow levels near magma but at deep levels under normal conditions of burial and heating in a subduction zone or accretionary prism none of these
in a subduction zone or accretionary prism
Marble is a metamorphic rock that forms from a ___________ parent . granite limestone sandstone shale
limestone
Which mineral is responsible for the strong foliation in a schist? quartz calcite mica foliate
mica
In what environments does low pressure/high temperature metamorphism occur? near magma but at shallow levels near magma but at deep levels under normal conditions of burial and heating in a subduction zone or accretionary prism none of these
near magma but at shallow levels
In what site on this figure would you expect low pressure/high temperature metamorphism? A B C D E
not D
Which of the following metamorphic rocks is not paired with its true parent rock? slate-basalt quartzite - sandstone gneiss - granite marble-limestone
slate-basalt
In regional metamorphism the source of increased temperature and pressure is _________ . a local intrusive heat source impact metamorphism the increase in temperature with increasing depth of burial and compression due to increased rate of radioactive decay
the increase in temperature with increasing depth of burial and compression
If granite is subjected to high temperature and pressure, it may eventually metamorphose to become a gneiss. However, when a gneiss is brought to lower temperatures and pressures, it does not metamorphose back to granite. Why not? All of the water has been forced out of gneiss so the retrograde reactions cannot occur Gneiss cannot be metamorphosed Granite cannot exist at low temperatures or pressures Metamorphism is the process of heating or pressurizing a rock, not cooling or depressurizing it Gneiss always converts back to granite at the surface
All of the water has been forced out of gneiss so the retrograde reactions cannot occur