Name______________________________________________________________________________
Abrasion Lab
Running water wears down earth’s surface. Running water can weather sediment (break it up
into smaller pieces). As sediment moves in a stream it bounces against other pieces of
sediment as well as the bottom of the stream channel.
During this process (abrasion), the edges of the sediment become more smooth and rounded.
Running water may also dissolve some minerals.
Question #1 – How is abrasion different in different materials?
Question #2 – How does the SHAPE of sediment change during abrasion?
Vocabulary
1. Abrasion = the act of wearing away sediment by rubbing, grinding or scraping.
2. Weathering = the act of breaking rock/sediment down into smaller pieces.
3. Sediment = small pieces of rock.
4. Erosion = the movement of rock/sediment.
5. Hardness = resistance to being scratched.
6. Dissolve = to mix with a liquid and become invisible.
7. Bedrock = solid rock in the earth.
8. Mass = the amount of matter in an object.
9. Matter = a thing that occupies space.
10. Dissolved load = when dissolved material is carried by a stream/river (see diagram
above).
11. Suspended load = when finer grained material is suspended in the water and carried by
a stream/river (see diagram above).
12. Bedload = when coarser grained material rolls, slides and bounces along the bottom of
a stream/river (see diagram above).
Materials
1. Limestone, quartz and halite (salt) chips
2. One plastic container and cap
3. Water
4. A stopwatch
5. A graduated cylinder
6. A strainer in the sink
7. A scale
8. Paper towels
Procedure 1 - LIMESTONE CHIPS
1. Weigh out approximately 100 grams of presoaked limestone chips.
2. Record the mass of the limestone chips in the “mass remaining” column for a time = 0
minutes on chart A of the report sheet.
3. Put the limestone chips in the plastic container.
4. Add approximately 200 ml of water to the plastic container.
5. Put the cap on the plastic container tightly.
6. Shake the plastic container for 3 minutes at a steady tempo.
7. After 3 minutes pour the water out of the container. Make sure the water goes through
the strainer so chips do not go down the drain.
8. Remove the limestone chips from the plastic container and dry them.
9. Weigh the chips on the scale. Do not throw these chips out, you still need them.
10. Record the mass of the chips in the “mass remaining” column for time = 3 minutes on
Chart A.
11. Return these limestone chips to the plastic container.
12. Repeat the shaking process three more times. You will shake the chips for 3 minutes at
a time, then dry and weigh them. Then record these masses in Table A. You will have
masses after shaking for 3, 6, 9, and 12 minutes when you are done.
13. Calculate the percent mass remaining after each of the shakes (every 3 minutes) using
the following formula:
Percent (%) mass remaining = mass after shaking
Mass at time 0
100
SHOW YOUR WORK ON THE NEXT PAGE – Do not just put the answer, please write
down what you are substituting into the formula then solve it. Put the answer in a
box.
At 3 minutes
At 6 minutes
At 9 minutes
At 12 minutes
14. Record the percent mass remaining of the limestone chips in Chart A.
15. On graph #1, plot the data for the percent mass remaining versus time for the
limestone chips. Draw a line graph. Do not start the Y axis at zero. Go over this line in
blue. Put a key on the bottom of the graph.
Procedure 2 – QUARTZ CHIPS
1. Repeat the steps of procedure 1 using quartz chips in place of limestone chips.
2. Record the data for the quartz chips in Chart B.
3. Calculate the percent mass remaining after each of the shakes (every 3 minutes) using
the following formula:
Percent (%) mass remaining = mass after shaking
Mass at time 0
100
SHOW YOUR WORK ON THE NEXT PAGE – Do not just put the answer, please write
down what you are substituting into the formula then solve it. Put the answer in a
box.
At 3 minutes
At 6 minutes
At 9 minutes
At 12 minutes
4. Record the percent mass remaining of the quartz chips in Chart B.
5. On graph #1, plot the data for the percent mass remaining versus time for the quartz
chips. Draw a line graph. Go over this line in red. Put a key at the bottom of the graph.
6. So now you have two lines on graph #1. One in blue for the limestone and one in red
for the quartz. You have a key on the bottom of the graph.
Procedure 3 – HALITE (SALT) CHIPS
1. Weigh approximately 100 grams of halite on the scale.
2. Put the halite in the plastic container.
3. Add approximately 200 ml of water to the plastic container.
4. Put the cap on the plastic container tightly.
5. Shake the plastic container for 3 minutes at a steady tempo.
6. After 3 minutes pour the water out of the container. Make sure the water goes through
the strainer so chips do not go down the drain.
7. Remove the halite from the plastic container and dry it.
8. Weigh this halite on the scale.
9. Record the mass of the halite in the “% mass remaining after 3 minutes” column in
Chart C.
10. On Chart C, fill in the percent mass remaining after 3 minutes for the limestone and
quartz chips.
11. On graph #2, plot the data from Chart C as a bar graph. Make sure you write
“limestone”, “quartz”, and “halite” on the x axis under the bars.
12. Answer the questions in clear, complete sentences.
Questions
1. This experiment was intended to show you how abrasion affects sediment in a
stream/river but we did not use a real stream or river.
How did we create an environment that shows how sediment is abraded in a
stream/river?
2. Do you think the experiment it was effective? Why was it/why was it not effective in
your opinion?
3. Which material abraded the least?
4. Which material was the hardest?
5. What effect does hardness have on the rate at which a rock abrades?
6. What special characteristic made the halite abrade so much? (Not that it is so soft)
7. How do you think halite is probably carried in a stream/river?
8. Describe what the halite looked like after it was shaken for 3 minutes (think of its size
and shape).
9. What happens to the size and shape of sediment as it abrades?
10. List and briefly explain the three ways that a stream/river carries sediment material?
1.
2.
3.
Report Sheet
CHART A – LIMESTONE
Weathering Time
Mass Remaining
(minutes)
(grams)
% Mass Remaining
0
3
6
9
12
CHART B – QUARTZ
Weathering Time
Mass Remaining
(minutes)
(grams)
% Mass Remaining
0
3
6
9
12
CHART C
Type of Rock Material
Limestone
Quartz
Halite
% Mass Remaining after 3 minutes
% Mass Remaining
Graph #1
Time (minutes)
% Mass Remaining
Graph #2
Time (Minutes)