metamorphic rocks
Vesicles are the result of
gas expansion (bubbles), which often occurs during volcanic eruptions.
Metamorphic rocks with segregated light and dark minerals are called
gneiss
Porphyritic textured rocks
is really a subtype, but usage of the term often confuses the beginner. rocks are composed of at least two minerals having a conspicuous (large) difference in grain size.
What does the term protolith mean?
parent rock before metamorphism
What metamorphic environment is most likely to result in the rock gneiss?
regional metamorphism
granite chemical composition
felsic
Which of the following rocks represents the highest metamorphic grade
gneiss
which rock has mineral banding where the light and dark minerals are separated?
gniess
Place these rocks in order from highest silica content to lowest silica content.
granite diorite gabbro peridotite
Which of the following metamorphic rocks is not paired with its true parent rock?
hornfels - dolomite
Vesicular
if the rock contains numerous holes that were once occupied by a gas phase, then this term is added to the textural description of the rock.
Scoraceous
if vesicles are so abundant that they make up over 50% of the rock and the rock has a density greater than 1, then the rock is said to be scoraceous.
Pumiceous
if vesicles are so abundant that they make up over 50% of the rock and the rock has a density less than 1 (i.e. it would float in water), then the rock is pumiceous.
In contact metamorphism there is a
local heat source
The metamorphic rock that is white, but it can occur in a variety of colors. It will fizz with hydrochloric acid. What is it's rock name?
marble
Which of the following metamorphic rocks can not form from a shale?
marble
nonfoliated rocks
marble ambhibolite quartzite
Previously existing rocks transform into new rocks due to an increase in heat and pressure
metamorphic
During metamorphism a quartz arenite will change into what type of rock
quartzite
As magma moves up through the crust, pieces of already solidified rock fall into the magma chamber. What is the name for this process?
Magma assimilation
What process allows for a previously existing rock to change WITHOUT melting?
Solid state recrystallization
Phaneritic cooling
This texture forms by slow cooling of magma deep underground in the plutonic environment.
The intrusion of dikes and sills would likely cause what type of metamorphism?
Contact metamorphism
What are the three main categories for depositional environments?
Continental Marine Transitional
What is the name of our state rock?
Serpentinite
A geothermometer is?
a mineral assemblage that can reveal the minimum temperature attained during heating
Fibrous
a term used to describe grains that occur as long fibers
Acicular
a term used to describe grains that occur as long, slender crystals.
Prismatic
a term used to describe grains that show an abundance of prism faces.
Tabular
a term used to describe grains with rectangular tablet shapes.
Spherulitic
a texture commonly found in glassy rhyolites wherein spherical intergrowths of radiating quartz and feldspar replace glass as a result of devitrification.
Graphic
a texture consisting of intergrowths of quartz and alkali feldspar wherein the orientation of the quartz grains resembles cuneiform writing. This texture is most commonly observed in pegmatites.
Obicular
a texture usually restricted to coarser grained rocks that consists of concentrically banded spheres wherein the bands consist of alternating light colored and dark colored minerals.
What are the categories of sedimentary rocks? Select all that apply.
biochemical chemical organic detrital
what minerals are found in Phaneritic Rocks
biotite mica, potassium feldspar, quartz, hornblende
Which of the following metamorphic rocks forms in the forearc of a subduction zone
blueschist
In which of the following metamorphic environments would you expect to find bedding and other sedimentary structures to be preserved
burial metamorphism
Limestone and marble are made up of the mineral
calcite
Alluvial fan/deltas
conglomerate
Sediments are broken rock and mineral fragments only.
false
What is the chemical composition of andesite?
intermediate
Shallow marine
limestone
A rock that has undergone cataclastic metamorphism would most likely display which of the following
pulverized rock fragments
magma type Andesitic
solidified Andesite
magma type Basaltic
solidified Basalt
magma type Rhyolitic
solidified Rhyolite
A combination of shallow earthquakes, tension, and contact metamorphism characterizes
spreading centers
In regional metamorphism the source of increased temperature and pressure is
the increase in temperature with increasing depth of burial
The pressure and heat that drive metamorphism result from which three forces?
the internal heat of the Earth, the weight of overlying rocks, and horizontal pressures developed as rocks become deformed
Which of the following is not used to classify foliated rocks
the texture of the parent rock
Pyroclastic Texture
those blown out into the atmosphere during violent volcanic eruptiions. These rocks are collectively termed fragmental. t is comprised of numerous grains or fragments that have been welded together by the heat of volcanic eruption.
Porphyritic cooling
undergone two stages of cooling; one at depth where the larger phenocrysts formed and a second at or near the surface where the matrix grains crystallized.
Vesicular Texture
vesicles (holes, pores, or cavities) within the igneous rock.
Which category of sedimentary rocks is classified mainly be it's grain size?
Detrital
What type of metamorphism lead to the formation of our state rock?
Hydrothermal metamorphism
examples of limestone.
Oolitic Chalk Coquina
What is the one and only texture that an intrusive igneous rock can have? (according to my powerpoint)
Phaneritic
Pumice and scoria are common types of
Vesicular rocks
Incomplete melting of rocks within our crust due to differences in melting temperatures is termed....
partial melting
what metamorphic rock has a waxy appearance.
quartzite
During metamorphism, changes in the bulk composition of a rock occur primarily as a result of
reaction with hydrothermal fluids
What type of metamorphism is caused by high temperature and high pressure imposed over a large volume of crust
regional
glassy textured rocks
textured igneous rocks are non-crystalline meaning the rock contains no mineral grains.
Phaneritic textured rocks
textured rocks are comprised of large crystals that are clearly visible to the eye with or without a hand lens or binocular microscope. The entire rock is made up of large crystals
Metasomatism is
the change in the bulk composition of a rock during metamorphism
What is the relationship between metamorphic foliation and sedimentary bedding
there is no regular relationship between sedimentary bedding and metamorphic foliation
a very smooth, silica rich rock. It was often used to make arrowheads, and today jewelry. There are a lot of variations of this one rock. It is also a sedimentary rock! What is it's rock name?
chert
What TWO rocks have a gravel sized grains?
conglomerate & breccia
Which type of pressure will result in the alignment of metamorphic minerals?
directed pressure
glassy cooling
results from cooling that is so fast that minerals do not have a chance to crystallize. This may happen when magma or lava comes into quick contact with much cooler materials near the Earth's surface.
Beach, barrier island
sandstone
The atmosphere causes erosion and weathering of rocks/minerals which eventually solidify into a new rock.
sedimentary
Deep ocean
shale
Which of the following sets is arranged in order of increasing metamorphic grade?
shale - slate - phyllite
index minerals forms at the highest metamorphic grade?
sillmanite
Select all the foliated rocks.
slate phylitle schist gneiss
A rock rich in garnet and pyroxene that forms at extremely high pressures and moderate to high temperatures is called a(n)
eclogite
lava cools rapidly not allowing any mineral crystals to grow
extrusive igneous
There are two categories of metamorphic rocks. What are they?
foliated, nonfoliated
The parallel alignment of mica in a metamorphic rock is an example of
foliation
What is the most prominent textural feature of regional metamorphic rocks?
foliation
Which of the following rocks formed extrusively? Select all that apply.
Basalt Rhyolite
Within a 50 mile traverse you walk from a shale into a slate into a phyllite. You are walking in the direction of
increasing metamorphic grade
Magma cools slowly forming large minerals.
intrusive igneous
A Geologist suffers from a black eye after yelling "Gneiss!!!" to a classmate, who happened to be sunning on a large boulder. The geologist really meant to tell the classmate that the rock they were laying on
is a high-grade, silicate-rich, mineralogically banded metamorphic rock
retrograde metamorphism
is the process where rocks previously metamorphosed under high-grade conditions are later metamorphosed under low-grade conditions
You observe mud cracks in the rock record. What depositional environment would be the safest interpretation of this observation?
Dried lake bed (playa)
Depositional environments are where the sediment was deposited after it was lithified.
False
Marble is a metamorphic rock that forms from a ___________ parent
limestone
Which of the following rocks would react with hydrochloric acid because it's made of calcite?
limestone
Sediments become sedimentary rocks through the process of
lithification
chalk is actually an example of which sedimentary rock?
Limestone
Which of the following rocks can be considered gradational between an igneous rock and a metamorphic rock?
migmatite
Both ____ and ____ rocks can be porphyritic,
aphanitic and phaneritic
Hydrothermal metamorphism is very common in which of the following settings?
at mid-ocean ridges
What igneous process is most probably at a divergent boundary?
decompression melting
Metamorphism occurs
adjacent to igneous intrusions, along faults, in subduction zones
A magma
consists mostly of liquid rock matter, but may contain crystals of various minerals, and may contain a gas phase that may be dissolved in the liquid or may be present as a separate gas phase.
The main factor that determines the texture of an igneous rock is the
cooling rate
An igneous rock is any
crystalline or glassy rock that forms from cooling of a magma.