- What was the first major effect of the moon being knocked out of orbit? How did that affect the world?
- Why was the climate so dramatically different? What impact did that have on people’s chances for survival?
- Which of the things that Miranda has to do without do you think would be the hardest for you to live without? Why?
- This natural disaster is very extreme: is there any part of what happens that seems realistic?
Sinkholes in a Cup
Learning Outcomes Statement:
The Sinkholes in a Cup activity encourages students to work together in exploring the nature of sinkholes. This will develop the core academic skills of teamwork and collaboration, by having them plan, organize, and reflect on the activity.
- 8 oz. foam cup
- scouring pad or very thin sponge
- empty 2-liter soda bottle
- piece of paper
Library Resources/Materials to Share:
333.7909113 MCPHERSON Arctic Thaw: Climate change and the global race for energy resources by Stephanie Sammartino MacPherson
FIC PFEFFER, S. Life as we knew it by Susan Beth Pfeffer
DVD 551.447 NOVA Nova. Sinkholes [videorecording] : buried alive by LarryKlein (Producer).
Y 577.078 RYBOLT Environmental science fair projects using water, feathers, sunlight, balloons, and more by Thomas R. Rybolt
LAFS.910.RST.1.1: Cite specific textual evidence to support analysis of science and technical texts, attending to the precise details of explanations or descriptions.
LAFS.910.RST.1.2: Determine the central ideas or conclusions of a text; trace the text’s explanation or depiction of a complex process, phenomenon, or concept; provide an accurate summary of the text.
SC.912.E.6.In.4: Identify natural geological processes that change the land and water in Florida, including beach erosion and sinkholes.
Notes for Introduction:
Sinkholes are natural depressions in the land caused when limestone and soils dissolve. They form when groundwater removes rock underground. They can form by slow gradual sinking or by sudden collapse of an underlying hole.
Sinkholes are common in about one quarter of the U.S. You can usually identify them as circular or oval low spots in fields that may gather standing water after rains. They can be small or larger than a football field. A sinkhole of any size indicates there was a cavity in the bedrock near the surface. Sinkholes are evidence of a subsurface groundwater, either in the past or present. Formation of a new sinkhole or continued collapse of an existing sinkhole, indicates present day groundwater.
People can affect the location and rate at which sinkholes form. One way sinkholes form is by the removal of large amounts of water from the ground for human use, livestock, or irrigation. This may lower the water table rapidly. Because of the loss of the water, the land surface can collapse into holes already formed in the underlying limestone.
Have students work in groups of 3-4. Provide these instructions to each group, along with the materials. When the groups have completed the activity, bring them back together and use the questions for a class discussion.
- Make a hole about the size of your thumb in the bottom of the foam cup.
- Cut a circle the size of the cup bottom from a thin scouring pad. Place this circle in the bottom of the cup.
- Place a column of sugar in the center of the cup and surround it by sand. To do this, make a tube by rolling up a piece of paper and place it in the center of the cup. The paper tube should be about the same height and one half the diameter of the cup. Fill the inside of the tube with sugar and the outside of the tube with sand (the sand should be between the paper tube and the sides of the cup). Carefully remove the paper tube. Place a thin layer of sand over the sugar.
- Cut the bottom off a two-liter soda bottle at about the same height as the foam cup to create a dish. Fill it about one-third full of water. This will symbolize groundwater.
- Place the cup with the sugar and sand in the water. Watch as the water fills into the cup and the sugar dissolves and runs out. A sinkhole is formed in the cup as the surface sand sinks into the area where the sugar dissolved. (You may need to remove the cup from the dish of water to allow the water to drain out of the cup and the sinkhole to form).
Questions for Feedback and Reflection:
- What natural process is demonstrated as the sugar is dissolved by the water and the surface sinks?
- What type of rock does the sugar represent?
- What characteristics must a rock have to be suitable for forming sinkholes and caves?
- What does the water in the dish represent?
- Why did the sinkhole form only over the sugar deposit?