Wind, water, ice and snow can erode rocks, cliffs and mountains, creating soil and gravel.
Freezing and thawing, sunlight, wind, water and chemical reactions all weaken rocks, causing them to crack, break and wear down into smaller pieces. Air, water and gravity combine to carry the pieces away from their points of origin. Eroded rock combines with decaying organic matter to become soil. Understanding weathering and soil formation can prevent building where landslides, earthquakes, volcanic eruptions, dust storms and floods are likely to occur. Does this Spark an idea?
Make Glacier Models
Line a 2-qt. bowl with a plastic grocery bag. Place a fist-size rock in the bowl. Measure 1/4 cup of medium gravel, 1/2 cup of fine river pebbles, and 1 cup of sand into a 2-qt. bowl. Fill with water and stir. Place the bowl in the freezer until the water has frozen solid.
Remove your glacier model from the freezer and place it on its flat side, on a slope of about 45 degrees. Take notes as your glacier model melts. The Illinois State Museum Geology Online website recommends recording the behavior of glacier models on a wet surface as well as on soil and sand.
Split "Rocks"
Mix plaster of Paris according to package directions. Fill an 8-oz., 3-inch tall yogurt container with medium gravel. Fill a second container with fine river gravel, about 3 mm to 6 mm in diameter. Fill a third container with sand, and leave a fourth container empty. Stir the gravel in the first container as you add the plaster of Paris, until the container is full. Repeat for the second and third containers. Fill the fourth container with plaster of Paris only.
Allow all four containers to harden for four to six hours or more. Remove each hardened "rock" from its container and carve a 1/4-inch to 1/2-inch groove across each rock's diameter, as described by Indiana Geological Survey geologist Deborah Hanuscin. Place each rock upright in a 4-qt or larger flat-bottomed bowl or container, deep enough to cover them with water. Place the bowl in the freezer until the water has frozen solid.
Remove your rocks from the freezer, and observe them while they thaw. Return them to the container, covered with water, and freeze them again. Repeat freezing and thawing until your rocks crack or break apart. Record how many freezes and thaws it took to for the rocks to crack.
Build a Worm Bin
Observe how kitchen waste and garden trimmings become soil by making a worm bin. Drill drain holes every six inches in the bottom of a 20-by-24-by-12-inch plastic storage bin, which is the size recommended by the late Worm Woman, Mary Appelhof, if you want your worms to compost five pounds of garbage a week.
Place the 20-by-24-by-12-inch plastic storage bin inside a 22-by-26-by-6-inch under-bed storage bin. This second bin will prevent your worm bin from leaking. Fill the smaller bin halfway with dampened, wrung-out shredded, corrugated cardboard or non-glossy newspaper, as recommended by Extension Associate Soni Cochran, from the University of Nebraska-Lincoln. You can also use shredded leaves, straw, hay or sawdust as bedding material, advises New Mexico State University Extension Horticulture Specialist, George W. Dickerson.
Appelhof, Cochran and Dickerson all advise adding one pound red wriggler worms for every 1/2-pound of garbage the worms will eat. Add gritty substances, such as cornmeal, coffee grounds or crushed eggshells, because worms have a gizzard, like chickens, that helps them digest their food, advises Cochran.
Document the day you add worms to your bin. Record the date and amount of kitchen scraps each time you add them. Record the number of days it takes for your worms to turn everything into soil, and the amount of soil they produce.
Tags: container with, plaster Paris, with water, 20-by-24-by-12-inch plastic, 20-by-24-by-12-inch plastic storage, 2-qt bowl
