Why are there so many historic stone walls weaving through Connecticut forests? When 18th-century farmers cleared the land, they discovered a never-ending supply of glacial rocks. Even after clearing a field, more rocks would magically appear the next spring. This simulation models frost heaving—the mechanical weathering process where water freezes, expands by 9%, and pushes rocks upward through the soil cycle after cycle.
Connecticut's glacial soil is full of buried rocks. Water expands by about 9% when it freezes into ice. Before you start the simulation, predict how many freeze-thaw cycles (years) it will take for the first buried rock to reach the surface. Consider: what role do soil moisture, soil type, and winter severity play?
Water migrates toward the freezing front and expands, forming an ice lens beneath the rock. When the ice melts, fine soil particles fill the gap, ratcheting the rock upward.
Unlike almost all other substances, water expands by about 9% when it freezes into ice.
During a New England winter, the freezing front penetrates the soil. Water migrates toward the cold front and freezes, forming ice lenses under rocks. Because water expands, these ice lenses physically lift the rocks upward.
In spring, the ice melts. The cavity left beneath the rock fills with fine soil particles, preventing the rock from falling back down. Over many freeze-thaw cycles, rocks migrate entirely to the surface!
| Year | Season | Frost Depth | Surface Rocks | Soil Type |
|---|