exogenic processes

• geologic processes

  • natural forces and mechanisms that shape and modify the earths surface overtime
• geologic processes

  • natural forces and mechanisms that shape and modify the earths surface overtime
• exogenic

  • exogenic processes is driven by external forces that operate and act on the surface of the earth
  • exogenic forces result in destruction of landforms through weathering and erosion
• exogenic

  • exogenic processes is driven by external forces that operate and act on the surface of the earth
  • exogenic forces result in destruction of landforms through weathering and erosion
• exogenic processes

  • weathering is the disintegration and decomposition of rocks in situ (no transportation involved)
  • erosion is the removal and transportation of material by water, wind, ice, or gravity
  • deposition is the settling of sediments into a new location
• exogenic processes

  • weathering is the disintegration and decomposition of rocks in situ (no transportation involved)
  • erosion is the removal and transportation of material by water, wind, ice, or gravity
  • deposition is the settling of sediments into a new location
• interconnectedness of exogenic processes

  • weathering is the breaking down of rocks and minerals
  • erosion is the movement of the weathered material
  • decomposition if the dropping off of the eroded material
• interconnectedness of exogenic processes

  • weathering is the breaking down of rocks and minerals
  • erosion is the movement of the weathered material
  • decomposition if the dropping off of the eroded material
• physical or mechanical weathering

  • disintegration and reduction of rock size without changing its chemical composition
• physical or mechanical weathering

  • disintegration and reduction of rock size without changing its chemical composition
• types of physical or mechanical weathering

  1. exfoliation
  2. frost wedging
  3. salt wedging
  4. temperature changes
  5. abrasion
• types of physical or mechanical weathering

  1. exfoliation
  2. frost wedging
  3. salt wedging
  4. temperature changes
  5. abrasion
• exfoliation

  • pressure in a rock is released along parallel lines near the surface of the rock
  • layers of the rock break off and fall
• exfoliation

  • pressure in a rock is released along parallel lines near the surface of the rock
  • layers of the rock break off and fall
• frost wedging

  • caused by freeze and thaw of water trapped between the racks of the rock
  • when water freezes, it expands and applies pressure to the rock forcing it to separate more
• frost wedging

  • caused by freeze and thaw of water trapped between the racks of the rock
  • when water freezes, it expands and applies pressure to the rock forcing it to separate more
• salt wedging

  • occurs when salts cryztalize as water evaporates
  • as salt crystals grow, it applies pressure to the rock which weakens it, eventually the rock cracks and breaks down
• salt wedging

  • occurs when salts cryztalize as water evaporates
  • as salt crystals grow, it applies pressure to the rock which weakens it, eventually the rock cracks and breaks down
• temperature changes

  • relationship of temperature to minerals; higher temp = minerals expand, lower temp = minerals contract
  • the gradual expansion and contraction of mineral weakens the rock
• temperature changes

  • relationship of temperature to minerals; higher temp = minerals expand, lower temp = minerals contract
  • the gradual expansion and contraction of mineral weakens the rock
• abrasion

  • rocks collide against each other while being transported
  • weathers the rock surface and breaks it into smaller particles then grains
• abrasion

  • rocks collide against each other while being transported
  • weathers the rock surface and breaks it into smaller particles then grains
• types of weathering

  1. physical or mechanical
  2. biological
  3. chemical
• types of weathering

  1. physical or mechanical
  2. biological
  3. chemical
• biological weathering

  • disintegration or decay of rocks caused by chemical or physical agents of organisms
• biological weathering

  • disintegration or decay of rocks caused by chemical or physical agents of organisms
• examples of biological weathering

  1. organic activity
  2. rock disintegration by plant growth
  3. burrowing and tunneling organisms
• examples of biological weathering

  1. organic activity
  2. rock disintegration by plant growth
  3. burrowing and tunneling organisms
• organic activity

  • from lichen and algae or secretion of acids
  • lichen is a symbiotic relationship between algae and moss
  • leaches minerals from the rock causing it to weaken and breakdown
  • decaying of plant minerals produces acid that dissolves exposed rock
  • presence of organisms growing, expanding, and moving on the surface of a rock exerts abrasion and pressure
• organic activity

  • from lichen and algae or secretion of acids
  • lichen is a symbiotic relationship between algae and moss
  • leaches minerals from the rock causing it to weaken and breakdown
  • decaying of plant minerals produces acid that dissolves exposed rock
  • presence of organisms growing, expanding, and moving on the surface of a rock exerts abrasion and pressure
• rock disintegration by plant growth

  • most common form
  • plant roots penetrate into cracks of rocks and cuases the rock to split into smaller particles
• rock disintegration by plant growth

  • most common form
  • plant roots penetrate into cracks of rocks and cuases the rock to split into smaller particles
• burrowing and tunneling organisms

  • animals burrow into rocks and causes it to break down and disintegrate
  • small animals like worm and insects contribute to this
• burrowing and tunneling organisms

  • animals burrow into rocks and causes it to break down and disintegrate
  • small animals like worm and insects contribute to this
• chemical weathering

  • involves chanegs of chemical composition of weathered material
• chemical weathering

  • involves chanegs of chemical composition of weathered material
• processes of chemcial weathering

  1. hydrolysis
  2. hydration
  3. oxidation
  4. carbonation
• processes of chemcial weathering

  1. hydrolysis
  2. hydration
  3. oxidation
  4. carbonation
• hydrolysis

  • reaction between mineral and water ions
  • results to rock surface decomposition by forming new compounds and by increasing the solution pH
  • silicate minerals form clay
• hydrolysis

  • reaction between mineral and water ions
  • results to rock surface decomposition by forming new compounds and by increasing the solution pH
  • silicate minerals form clay