Mechanical/physical weathering

• mechanical weathering occurs when exposed rocks are physically broken down into smaller pieces called regolith
• mechanical weathering takes place on areas of weakness in rock
• mechanical weathering mainly takes place in areas of extremes of temperature such as deserts and mountains
• There are two main types of mechanical weathering:

  • Freeze-thaw action
  • Exfoliation
• Freeze-thaw action can also be called frost shattering
• Freeze-thaw action is the most common type of mechanical weathering
• Freeze-thaw action is common in upland areas as where there is a plentiful supply of precipitation and temperatures fluctuate above and below freezing
• Water fills the cracks during the day when the temperature is warm