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SEDIMENTARY ROCK IDENTIFICATION LAB
Submission Information
Name: Date:
Objective
To identify sedimentary rocks based on grain size, texture, and composition
Materials
• Clastic/Chemical Sedimentary Rock Charts
• Mohs Hardness Scale (Optional)
Purpose (5 pts)
Write 1–2 sentences stating the purpose of this lab. What do you expect to learn?
What do you want the outcome to be?
Hypothesis (5 pts)
If you are able to correctly identify the texture, grain size, and composition of each
sample, what will be the result? State your answer in a complete sentence.
Procedure
1. Read through all of the steps in the procedure as well as the Data section. Then
complete the Purpose and Hypothesis sections.
2. Using the information provided in the Data table and the Clastic and Chemical
Sedimentary Rock Chart complete the Data table and name each sedimentary
rock.
3. Complete the Observations, Analysis and Conclusion, and Application sections
before submitting the lab assignment.
Ava Philbrok
10/14/2020
The purpose is to identify the sedimentary rocks based on their texture,grain size, and composition. I expect the outcome to be
having them all listed as correct and, I expect to learn how to tell the rocks apart.
If i am able to correctly identify each rock the result will be that I got them all correct.
2
Data (60 pts)
You may want to refer to the Mohs Hardness scale chart from the Mineral
Identification Lab to help you decipher the composition based on hardness. You will
also want to keep in mind that calcite reacts with Hydrochloric acid.
(2 pts per blank = 60 pts total)
No. Image
Category
Clastic, Chemical,
Organic/Biologic
Texture Hardness
Composition or
Sediment Name
Rock
Name
1
Fine to
Coarse
Crystalline
3
2
Organic/
Biologic
3
3
Fine to
Coarse
Crystalline
2
Calcite and Some
Shell and Skeliton
Fragments
43
5
Very Fine
(< 1/256
mm)
N/A Mud
6N/A
7> 2 mm N/A
87 Silica (Quartz)
9N/A
10 Biologic N/A
Altered Plant
Fragments
Data Table 1
chemical
calicte
crystalline
limestone
shells and
cemented
shell
fragments
mineral calcite
chemical
gypsum
chemical
shells and
shell
fragments
calcite
clastic
Shale
clastic
medium
sand
clastic
gravel
(rounded fragments)
clastic
very fine
siltstone
clastic
coarse
gravel
(angular fragments)
fine-grained
organic matter
bituminous
coal
cogunia
fossiliferous
limestone
sandstone
conglomerat
e
Breccia
chemical
calicte
chemical
calicte
crystalline
limestone
cogunia
mineral calcite
shells and
cemented
shell
fragments
chemical
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Observations (10 pts)
What do you notice about the differences between clastic, chemical, and organic
sedimentary rocks from the samples you looked at? State your answer in 2-3
sentences.
Analysis & Conclusion (10 pts)
Which characteristic was most helpful in identifying the rock (texture, grain size,
composition)? How could this lab exercise be improved? Is there any additional
information that would have been helpful to you in identifying the rock samples? Did
you struggle to identify any of the samples and if so, why? State your answer to these
questions in complete sentences.
Application (10 pts)
Imagine you are walking in the woods and you come across a gray rock composed of
a number of different fossilized organisms such as crinoids, trilobites, and
brachiopods, you pour some hydrochloric acid on the rock and notice that it reacts to
the acid. Based on this information, what is the name of this rock and what does it tell
you about the environment in which it formed? State your answer in complete
sentences.
The textture is a big difference. The chemical rocks kinda look clear and see through because of the exoperated water.
The most helpful was the texture and the composition. I think this could be impoved if you had a few names scattered in the name
section of the box. One of the most helpful thing was the clastic and chemical sedimentary rock chart. I did struggle with identify a
few of the rocks becuase i couldnt seem to find something similair to those on the lessons.
The name of this rock is fossiliferous limestone and it reacted to this because its compostition and sediment is calcite. It tells us
alot about its enviroment mostlikely it was around abunch of shells like at the beach with muddy sand and when it washed up on
the shore it dried with th shells and dark.
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Works Cited
The following citations correspond respectively to the 10 images found in Data
Table 1.
1. Image by James St. John
2. Image by James St. John
3. Image by James St. John
4. Image by James St. John
5. Image by Sardaka
7. Image by James St. John
8. Image by Children’s Museum of Indianapolis
9. Image by Michael C Rygel
10. Image by Amcyrus
