Chapter 11 The Rock Cycle

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Chapter 11The Rock Cycle

• Section 11-3
• Sedimentary Rock

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I. How do Sedimentary Rocks form?

• Formed from sediments
• Weathering
• Breaks rocks or remains of plants and animals
  into smaller pieces called sediments.
• Erosion
• Sediments are transported to new locations by
  water, wind, ice, and gravity (transportation and
  deposition)

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• Deposited sediments can sometimes recombine to
  form solid rock.
• Formation of sedimentary rock
• Many layers of sediment are deposited
• Pressure from upper layers pushed down on the
  lower layers
• Sediments compress together to form rock
• Compaction/Lithification

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• Sediments can also form rock by
  Cementation/Lithification
• Layers of sediment accumulate
• Water is squeezed out from all of the pressure
  mineral deposits remain
• Minerals crystallize and cement together to form
  rock

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http//sln.fi.edu/fellows/payton/rocks/create/sedi
ment.htm
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II. Classifying Sedimentary Rocks

• Can be made of any type of weathered and eroded
  material
• Can be plants and/or animals
• Need to look at the sediment they contain and how
  they are formed.

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C. Detrital Sedimentary Rock

• Made of broken pieces of other rock
• Product of weathering
• Compacted and cemented (lithification)
• Can be large and rounded sediments
• Can be large sediments with sharp angles

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• Shale does not need a lot of cementation to hold
  particles together
• Has clay sized minerals

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• Sandstone is formed from quartz and feldspar.
• Sand is deposited in layers

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D. Chemical Sedimentary Rock

• Formed from dissolved minerals
• Were once chemical compounds
• Becomes concentrated when the water evaporates
• Rock Salt is formed when halite is carried in an
  ocean or lake. As the water evaporates, the
  concentration of the element increases

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E. Organic Sedimentary Rock

• Contain large amounts of once living things
  (fossils)
• Limestone si made of calcite, it also contains
  fossils of aquatic animals
• When mussels and snails die, their shells build
  up on the ocean floor, they compact and become
  cemented together and form rock.

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III. The Rock Cycle

• The process by which rocks change
• All rocks are formed by this cycle
• Rock Cycle Website

http//www.learner.org/interactives/rockcycle/inde
x.html