Name _______________________________________________
Date_______________________
Class Period _____
Instructor ___________________
Lab Period ______
5 points
Sedimentary
SEDIMENTARY ROCKS
 

CLASTIC


ORGANIC
CHEMICAL
1 point each
 


CARB
NON-CARBONATE




CARB
NON-CARB
1 point each
CARB
NON-CARB
Name the Rocks. 3 points each.
S1.
_________________________
S2.
_________________________
S3.
_________________________
S4.
_________________________
S5.
_________________________
S6.
_________________________
S7.
_________________________
S8.
_________________________
S9.
_________________________
S10. _________________________
S11. _________________________
S12. _________________________
QUESTIONS:
3 points each. Use complete sentences for #1-4. No pronouns allowed.
1.
2.
3.
4
5.
A
B
C
D
6.
A
B
C
D
7.
A
B
C
D
8.
A
B
C
D
9.
A
B
C
D
10.
A
B
C
D
Lab #15 Sedimentary
INTRODUCTION: Please read this as it contains information that will help you complete
this lab successfully.
Sedimentary rocks are formed by the lithification (turning to stone) of sediments. Most of New
York State has sedimentary rock as bedrock. Vast oceans once covered New York State,
producing the sedimentary rocks. Most of the rocks that can be seen along New York
roadsides are layered sedimentary rocks.
Clastic sedimentary rocks are formed by the deposition, compression, and cementation of
broken rock (sediments). These rocks are classified by the size and shape of the sediments
contained in them. Clay particles form shale, silt forms siltstone, sand forms sandstone, large
rounded pebbles form conglomerate and large angular particles form breccia.
Some rocks are formed from living organisms or their shells. These are called organic
sedimentary rocks. The remains or impressions of plants and animals found in rocks are called
fossils. "Hard" parts of animals, such as bone and shells, are usually the only parts that become
fossilized. Sedimentary rocks are the only rocks that have fossils in them. Any organic
material would be destroyed in lava or magma and therefor no fossils are found in igneous
rocks. Likewise, the pressure required to create metamorphic rocks would destroy fossils.
Chemical sedimentary rocks can be formed by evaporation (evaporites) or the precipitation
from sea water (precipitates). Limestone, dolostone, halite and rock gypsum are all evaporites.
PROCEDURE:
PART ONE:
For each sedimentary rock, classify whether the rock is clastic, chemical or organic. Place the
code letter and number under the appropriate category on the report sheet. Clastic sedimentary
rocks show layering, feel very gritty, or have visible sediments. Organic sedimentary rocks
have fossils or shell fragments in them. Chemical sedimentary rocks generally do not exhibit
any of the characteristics of clastic or organic. They tend to be of one color and fairly solid in
appearance.
When each rock has been classified, place one drop of dilute hydrochloric acid (HCl) on each
rock. If the acid bubbles, the rock contains calcium carbonate (mineral calcite). The acid
reacts with calcium carbonate to form carbon dioxide, a gas, which causes the bubbling. These
rocks are called carbonates. If no bubbling occurs the rock is a non-carbonate. Write the code
letter and number in each category under carbonat e and non-carbonate. This will begin to look
like a family tree.
PART TWO:
Using the Earth Science Reference Tables, try to determine the name of the sedimentary rocks.
The chart is divided into clastic and non-clastic (chemical and organic). Further descriptions
on the chart can be used to pinpoint the rocks' names.
QUESTIONS: Use complete sentences for questions #1-4. No pronouns allowed.
1.
How could a clastic sedimentary rock appear to be chemical?
2.
Would sedimentary rocks form at high elevations or low elevations? EXPLAIN.
3.
Why wouldn't fossils be found in igneous or metamorphic rocks?
4.
Why aren't there many fossils of skin or muscle tissue of animals?
5.
What would a rock formed by the compaction and cementation of angular sediments 1
cm. in size be called?
A)
sandstone
B)
breccia
C)
conglomerate
D)
limestone
6.
Which rock is most likely to fizz in acid?
A.
rock salt
B)
gypsum
C)
limestone
D)
shale
7.
Which rock is most likely formed by the precipitation from sea water?
A)
sandstone
B)
gypsum
C)
conglomerate
D)
bituminous coal
8.
Which rock is composed of the smallest size sediments?
A)
shale
B)
siltstone
C)
sandstone
D)
conglomerate
9.
Which property best describes a rock which has formed from sediments?
A)
crystalline structure
B)
distorted structure
C)
banding of minerals
D)
particles arranged in layers
10. Which property is used to classify the land-derived sedimentary rocks listed in the Earth
Science Reference Tables?
A)
particle size
B)
fossil content
C)
mineral composition
D)
color