Sedimentary Rocks

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Name _________________________________________________
Date_______________________
Lab Period _______
Lab Day ______
Sedimentary Rocks
PART 1:
Clastic
Organic
Chemical
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PART 2:
1.
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5.
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2.
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6.
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3.
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7.
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4.
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QUESTIONS: Use complete sentences for questions #1-4
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 #8
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 1: Group the rocks. Put the number of the rock in the categories below. Use the
descriptions below to help you decide.
Clastic – show layering, feel very gritty, or have visible sediments
Organic – have fossils or shell fragments in them
Chemical – generally do not exhibit any of the characteristics of clastic or organic. They
tend to be of one color and fairly solid in appearance.
PART 2: Name the rocks. Using your Reference Tables, draw the map symbols in the box
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
C)
conglomerate
B)
breccia
D)
limestone
6.
Which rock is most likely to fizz in acid?
A) rock salt
B)
gypsum
C)
D)
limestone
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
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