GEOL111_Rocks2Lab.docx
pdf
keyboard_arrow_up
School
Binghamton University *
*We aren’t endorsed by this school
Course
111
Subject
Geology
Date
Apr 3, 2024
Type
Pages
7
Uploaded by DoctorHeat13765
Metamorphic Environments:
Match the images with possible types of metamorphic environments. Options: impact metamorphism,
regional metamorphism, contact metamorphism, hydrothermal metamorphism. Some options can be used
more than once.
A
D (entire ridge)
B
E (image is underwater)
C
F
For each image, describe the type of plate tectonic boundary, where the point is located relative to the
boundary, the intensity of pressure and temperature possible, and the metamorphic environment from the list
above. Fill in your responses in the table below.
Points
Plate Boundary or
hot spot (may be
not applicable); if
convergent, specify
type
Likely
pressure
Intensity
(high,
medium, low)
Likely
temperature
Intensity (high,
medium, low)
Metamorphic
environment
A
N/A (Crater formed
by a meteor?)
high
high
Impact
Metamorphism
B
Transform
Boundary
low
high
Contact
Metamorphism
C
Hot Spot
low
low
Hydrothermal
Metamorphism
D
Convergent
boundary
(oceanic-oceanic)
high
low
Regional
Metamorphism
E
Divergent Boundary
low
low
Hydrothermal
Metamorphism
F
Convergent
boundary
(continental-contin
ental)
high
low
Regional
Metamorphism
Building stones as a geology lesson:
1.
It’s time for a field trip! Hurray! Leave your stuff where it is-you won’t be going far. With your lab mates, go
to either staircase on the first floor of geology, either by the bathrooms or by the elevator. Open the door
to the staircase and look down- you’ve probably noticed every time you’ve been in here that the threshold
is a gorgeous rock, but alas, perhaps you have not had the geologic know-how to identify it. That changes
today.
Please be aware that other students may not have the same respect for geology and may be walking in and
out- be courteous, please
Sketch the patterns seen in this slab of rock or take clear photos of it (with a scale bar of some kind, please!
Rulers are in the lab).
a)
Describe this metamorphic rock using terms you’ve learned so far. Grain size, foliation, non-foliation,
etc.
●
This metamorphic rock is fine grained and the crystal size is small. It has little to no foliation,
but their are some bands present.
b)
Identify the features running across the slab. Describe how they came to be. Was it directed pressure?
Confined pressure? What type of metamorphism is it?
●
The features running across the rock seem to be lines and small bands. They look like seismic
wave lines. The lines look like graphite, so carbon was probably compressed at high
temperatures and pressure. It looks like it was formed, by confining pressure. This was likely
formed by contact metamorphism.
c)
Provide an image of the rock, either as a photo you took yourself (take your own photo, please) or a
sketch. Draw arrows indicating the directions of pressure.
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
●
d)
What type of rock is it? What was it’s protolith? Why do you think that?
●
I think this rock is a quartzite and its protolith is quartz sandstone. I say this because the rock is
fine relatively grained and has no foliaton accept for the bands of graphite.
2.
Our field trip now takes us to the Delta terminal at a California airport, where I came across this beauty of a
rock many years ago on my way home.
a)
Using arrows in Microsoft word, google docs, etc. alter this image by drawing arrows on the direction of
pressure you think this rock was under during the formation of its features.
b)
Zoom in to the image and describe the two major types of minerals here- the lighter and darker bands.
Were they felsic? Mafic? Which one- the darker or lighter bands- seems to be more “bent”?
a.
The lighter bands appear to be more felsic because they are light colored, while the dark band
more mafic because of their dark color. The two minerals present might be pyroxene and
feldspar. The lighter bands appear to be more bent.
c)
Take your knowledge of Bowen’s reaction series. Is it common for these two types of materials to be
present in the same type of rock? Yes or no and why? Do you think the two materials are from the
same source (i.e., parent rock, etc.) or not-why?
a.
It is not common to have felsic and mafic rocks in the same rock, as the darker and more mafic
materials crystalize first and form under different pressures and temperatures, then the more
felsic materials, as shown by Bowen’s reaction series. Because of this, I believe that the rock is
not from the same source or parent rock, as felsic materials have different melting
temperatures than mafic rock so it would be uncommon to find them in a rock together.
d)
Knowing what you know about felsic and mafic composition and properties, discuss how viscosity
would relate to how the material folds. Which one likely flowed more easily and which one not- which
one would have folded more, then, and why?
a.
Viscosity relates to how well a material flows and how easily it can deform and shape. The lower
the viscosity, the easier the rock is to bend and shape, since it flows relatively easily. Highly
viscous rocks generally don't flow, so they have a harder time bending and often resist
conforming. The darker-colored material likely flowed the easiest, while the lighter material
flowed the least. The lighter color is the one that folds the most since it seems more felsic,
which has a high viscosity, which means it is resistant to flow and will have a specific
orientation.
e)
You may have figured out this is a strange rock. Do you think this formed under low, medium, or
high-grade metamorphism- why?
a.
I think this rock is a high grade metamorphic rock because of banding of the lighter colored
minerals in it. Because it also has two different igneous rock types, it would need to undergo
high pressure and high temperature to metamorphose, making it high grade.
Identifying Metamorphic Rocks:
Using the table in your handout, determine the mineralogy and texture of the metamorphic rocks in your set.
Record the information in the chart below and name each specimen.
Available Rocks:
Gneiss
Marble
Phyllite
Quartzite
Schist
Slate
Amphibolite
Garnet gneiss
Serpentine
Soap stone
Specimen
Minerals Present
(Compositional Group)
Texture
(Grain Size, Shape,
Foliation)
Metamorphic type
(contact, regional, etc)
/Possible geologic
environment
Metamorphic
Grade
(Low,
Medium, or
High)
Rock Name
Possible protolith
3H
Garnet, Muscovite
Mica, mafic minerals
foliated, fine grain
igneous pluton, high
grade contact
metamorphism
high grade
Garnet
Gneiss
Gneiss
3A
quartz, muscovite mica
foliated, fine grain
new york mountains,
convergent
continental-oceanic
boundary (regional
metamorphism)
Low-grade
Slate
Shale
3C
Mica
foliated, small grained
Continental-oceanic
convergent boundary
(regional metamorphism )
Low-grade
Phyllite
Shale
3J
Quartz, Feldspar, Mica
foliated, medium
grained
Continental-oceanic
convergent boundary
(regional metamorphism)
medium grade
Schist
Phyllite
3D
Garnet, Muscovite
Mica, mafic minerals
foliated, medium
grained
igneous pluton, high
grade contact
metamorphism
High-grade
Gneiss
Granite
3F
Olivine
no foliation, fine grained
(some bigger crystals on
side)
Geysir, hydrothermal
metamorphism
low grade
Serpentine
Peridotite
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
3G
Calcite
no foliation, fine grain
Coral reef, possible
subduction zone
(accretionary prism)
low grade
Marble
Limestone
3E
Amphibole
weak foliation, long
crystals, small grained
igneous pluton, low grade
contact metamorphism
low grade
Amphibolite
Basalt
3I
Talc
no foliation, small
grained
Subduction zone, contact
metamorphism
low grade
Soap Stone
Basalt
3B
Quartz
no foliation, medium
grained
Continental-Continental
boundary (regional
Metamorphism)
low grade
Quartzite
Arcose Sandstone