The Weathering Process

Weathering is the breakdown of rocks at or near the Earth's surface due to mechanical (physical) and chemical changes. The two types of weathering are as follows.
  • Mechanical weathering takes place when rock is broken into smaller pieces without changing the chemical composition of the material.
  • Chemical weathering takes place when the rock's minerals are decomposed or dissolved in solution and changed into different substances.

Although mechanical and chemical weathering are studied separately, they almost always act together.

Homework: Due Friday, February 15, 2008

In review book, chapter 4, read pages 81-82; answer questions 1-16.

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