Sedimentary Rock Forming Processes

Mechanics

Feb 22, 2014 (4 years and 4 months ago)

65 views

Sedimentary Rock Forming Processes

Earth Science: Unit 4

Rock Forming Processes

Goal:

Part One

a.

Students will test out hypotheses
to determine

the relationship
between the amount of energy
present in the environment
and the
particle size in sedimentary

rock form
ed

in that environment.

b.

Students will determine that the particle size and the shape of the
grains in sedimentary rock can give an idea of the environment in
which sedimentary rock formed.

c.

E 3.1c
-

Explain how size and shape of
the
grains in sedim
entary rock
indicate the environment of formation and deposition.

Part Two

a.

Students will hypothesis and test the relationship between the amount
of time the sediments were transported and the size
and shape
of the
grain
s

in the resulting sedimentary rock
.

b.

Students will determine that the grain shape in sedimentary rock
reflects the amount of time the sediments were transported before the
rock formed.

c.

E3.1c
-

Explain how grain shape reflects duration of sedimentary
transportation of particles in sedimentary

rock.

Background

Grain size reflects the amount of energy in the environment that sediment
transportation occurred. Grain shape reflects the duration of sediment
transportation.

Here is a good website for students to look at after the activity. It sho
ws
different

environment
s

and the resulti
ng sedimentary rock
s

that formed in each
environment.

http://www.windows2universe.org/earth/geology/sed_river.html

Time frame:

Part on
e
-

25 minutes for steps 1
-
7 on day one. Five minutes on day two and ,if
last part is done, 4
-
5 weeks to let the water evaporate to observe the “rock”

Part Two
-

6
-
10

minutes each day for about 5
-
6 days.

Student Misconceptions

???

Vocabulary:

Grain size

G
rain shape

Sedimentary rocks

Sedimentation

Weathering

Materials:

Two

1
-
L pop bottle
s and caps

per group

Soil with different sized particles (gravel, sand, silt, clay)
-

Enough for each group
to have about 1 cup full.

Water

Epsom salts (to help the sedimenta
tion process at the end of the lab)
-

2 tbsp per
group

Marble chips
-

Procedure

Part One
-

How does the amo
unt of energy
in
moving water a
ffect the
size of
particles that settle out?

1.

Have students a
dd a mixture of gravel, sand, silt a
nd clay to
a 1
-
L

bottle in
what ever ratio they wish.

Epsom salts to the
mixture (if the students are going to actually make the “rock” in the
optional portion).

2.

¾’s
full. Put the ca
p on the
bottle.

3.

how
the amount of energy
in the swirling water
will

affect the
size of the
particle
s
that can
settle out

while the water is still
moving.

4.

Test the hypothesis out by applying different amounts of energy to swirl
the
bottle in a circular manner.

5.

Observe which particles are able to settle out with
different amounts of
energy

.

6.

Allow 6
-
10 minutes of “explore time” during which students make a list of
all the different things they observe as they move the bottle.

7.

L
et the bottle and its content
s

sit
still
for 2
-
3 minutes. Make
a

last
observation
for the day
rticles settle out of the water when
the water has very little moving energy.

8.

Set the bottle in a spot where it will be undisturbed until the next
class.

9.

Obs
erve the particles the next class

(or at the end of the first day if the
materials have had enough time to settle out)

10.

(Optional)
Take the cap off
the bottle and allow the water to

evaporate
(may take a while).
When the water has evaporated the
bottles can be cut
open and the “sedimentary rock” can be observed/broken apart to
see

the
inside layers.

Part Two
-

How do
es the duration of sediment

transportation affect grain
shape?

1.

Add a hand full of marble chips to an empty pop bottle.

2.

the bottle until the bottle is about ¾ ‘s full.

3.

Observe and describe the shape of the marble chips. Record your
observations.

4.

Keep one container as a

class

“control” container
-

do not shake the
marble chips in this container.

5.

the
amount/length of
shaking will affect the
marble chips in the container.

6.

Shake the container
s frequently

(6
-
8 minutes for 5
-
6 days)
over the next
few days
.

7.

After a few
days
of shaking compare the marble chips in the shaken
containers with the marble chi
ps in the container that was not shaken.

Expected Results

In part one
-

Students should observe
that the heavier/larger particles will be able
to settle (sink) even while a lot of energy is being used to rotate the container.
The smaller particles will
settle out when the water is calmer (less energy) and
the smallest particles may settle to the bottom after the container is left for a day
or two.

In part two
-

Students should observe that the marble chips are irregular and large
at the beginning when no

shaking has occurred. After a few days of shaking, the
marble chips will break down (smaller) and have rounder edges.

Sedimentary Rock Formation

Student Master

Na
me ____________________________

Part One
-

Energy
in the environm
ent
and particle size

in sedimentary rock

1.

Add a combination of gravel, sand, silt and clay particles to a plastic bottle.
Don’t fill the bottle more than halfway full with sediments.

2.

Add water to fill the bottle

Screw on the cap tight
ly! Use

a

permanent marker to write your name on the cap.

3.

Make a hypothesis about how the amount of
energy used to rotate the
bottle

will affect the settling of particles in the
bottom of the
b
ottle:

4.

Test your hypothesis out by swirling the bottle wit
h varying amounts of
energy
and observe

the particles that are able to settle
to the bottom of
the bottle.

5.

Describe your observations in the space below.

6.

Draw and label what you see in the bottle in the space below.

7.
What c
onclusions can you make about how energy in moving water

affects the size of the particles that are able to settle to the bottom of

the water?

8.

Describe the size of particles that would be foun
d in sedimentary rock that
formed

unde
r a fast flowing river.

9.

Describe the size of the particles that would be foun
d in sedimentary rock
that formed

under a lake.

Part Two
-

Length of transportation
of sediments and the shape of grains in
sedimentary rock.

1.

Add a hand full of marble chips
to an empty pop bottle.

2.

ttle until the bottle is about
¾ ‘s full.

3.

Observe and describe the shape of the marble chips. Record your

observations in the space below.

4.

The teacher will keep one container as a “control” container
-

this container
will not be shaken and will be used as comparison after the experiment.

5.

Make a hypothesis about how the shaking will affect the marble chips in
the container. Write your hypothesis in the space below.

6.

Shake the container
s frequently

(6
-
8 minutes for the next 5
-
6 days)
over
the next few days
.

7.

After a few days of shaking compare the marble chips in the shaken
containers with the marble chips in the container that was not shaken.

Record your observations in the space below.

8.

Make a con
clusion about how the amount of shaking and moving of
particles affects the size of the particles.

9.

Describe the particles you would find in sedimentary rock that formed after
the sediments were
transported
for a long time
in a river.

10.

Describe the par
ticles you would find in sedimentary rock that formed after
the sediments were transported for a short time or not at all.