Mechanical weathering, also known as physical weathering, refers to the process by which rocks and minerals are broken down into smaller pieces without changing their chemical composition. This type of weathering typically occurs through physical forces and environmental conditions that cause rocks to fracture, crack, and disintegrate.
Some factors that can cause mechanical weathering include:
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Temperature Changes: Fluctuations in temperature can lead to thermal expansion and contraction of rock materials. When rocks heat up, they expand, and when they cool down, they contract. This repeated cycle can create stress within the rock, leading to cracking and fragmentation.
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Frost Action (Freeze-Thaw Cycle): Water can seep into cracks and pores in rocks. When temperatures drop, the water freezes and expands, exerting pressure on the surrounding rock. Upon thawing, the water melts, and the cycle can repeat, progressively causing the rock to break apart.
Other factors could include the actions of plants (root wedging) and mechanical forces like wind or water erosion, but the two listed above are among the most significant in mechanical weathering processes.
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