Weathering in a Rock
Arts & Letters,
Summer Research Program for Science
General Science / Earth Science
SWBAT physically demonstrate weathering and erosion of different samples of
SWBAT use real-world examples to explain that weathering is the process that
break down rocks to form sediments.
SWBAT work collaboratively in groups to record measurements using
appropriate tools, observation, and attention to detail.
weathering, erosion, sediments,
scale or balance, rock tumbler, at least 5 different rock samples, each
approximately 7.5 cm in diameter by 2.5 cm in width, sand
Rock Tumbler Lab
is the (chemical or physical) process that breaks down rocks to form sediments;
weathering is caused by wind, water, ice and animals.
Erosion is the physical process that transports sediments over time.
A rock tumbler has an electric motor that allows rocks of various types
and hardness, in combination with sand (which acts as an abrasive agent to
physically weather the rock samples) and water will result in the weathering of
rocks over time. The rock tumbler
can also be used to model erosion in a stream, river or other moving water
source since the physical churning and motion of the rocks simulates a
fast-forward version of this kind of erosion.
students the Rock Tumbler Lab (or create an in-notebook version of this lab)
and the following scenario:
Catastrophe Construction Company based in Long Island, New York would like
to design a brand new, state-of-the-art home that is completely
“weather-proof.” The company would
like the new house to be built out of a material that will survive the
strongest storms in New York.
Since you have been studying weathering in your class, the company
has asked you to decide which of the five rock samples they have sent you
will make the best material to use to build their new “weather-proof”
design. Thanks for your help!
Divide class into groups of 3-4.
Observe: Have students describe and identify the rock samples using detailed
drawings, labels and measurements.
Design: With your lab group, create
an experiment, using a rock tumbler, to quantify (evaluate with numbers) the
rate at which different rocks weather and erode.
Predict: Make a hypothesis that includes a prediction about which rock will
be the most resistant to changing and which will be the least resistant.
Justify your predictions with an explanation based on what you know
about each rock.
Measure: Determine the mass of each
rock sample and record the data in the table provided on the worksheet, or
in your lab notebook. You will run
the tumbler for 24 hours, rinse the mud from the rocks and determine the
mass of the samples each day. Repeat for several 24-hour periods until clear
patterns emerge or specimens are abraded to mud.
Once you have completed all rounds of tumbling, graph your mass results
(using graph paper or Microsoft Excel). Place all five rocks in order from
most resistant to least resistant. Does the order match your original
prediction? Why or why not?
After discussing the results of the experiment as a class, estimate how far
the rocks travel in one day. Show your work.
How far would the rocks travel in 10 days? Compare this distance to the
length of some well-known rivers in the
Do you think the water in most rivers travels at a high enough speed to move
rocks of the initial weight? Explain your answer.
Finally, explain in a paragraph which rock sample you believe Catastrophic
Construction Company should use to build their new “weather-proof” homes.
Please give at least two reasons to support your claim.
This lab could extend for as little as a few days and as
long as a few weeks or more.
Students could bring in their own rock samples.
Students should at some point graph their data and carefully observe and
analyze any patterns they notice.
The use of technology to prepare graphs and/or present analyses could be applied
throughout the lab.
NY STATE STANDARD 1—Analysis, Inquiry, and Design
Students will use mathematical analysis, scientific inquiry, and engineering
design, as appropriate, to pose
questions, seek answers, and develop solutions.