Erosion,

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Erosion, Types of Weathering

• Chapter 10

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Erosion

• A process where water, wind, or gravity
  transports soil (sediment) from its source

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• The process by which rocks are broken down into
  smaller pieces
• There are 2 main types, chemical Physical

Weathering
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Mechanical Weathering

• The break down of rock into smaller pieces due to
  physical means
• Frost wedging (water freezing in rock cracks)
• Abrasion (other rocks or sediment rubbing against
  rock.)

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Chemical Weathering

• Rocks break as a result of a chemical change
• Acid rain
• Chemical decomposition
• Gases in the air (oxidation)

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Deposition

• Is the process where material lays to rest
• Sediment is deposited in bodies of water and on
  land

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Chapter 6

• The Rock Record

? ? ?
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• Sedimentary Rock Layers
• This is a normal record of rock. Layers are
  undisturbed. The Geologic Column is a model of
  what rock layers should look like.

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Uniformitarianism

• A principle or rule that states that events that
  happened in the past can be explained by current
  earth (geologic) processes
• Earth Processes like erosion, weathering, and
  deposition remain uniformed and do not change.

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Catastrophism

• A principle that states that geologic changes
  happen suddenly. (natural disasters)
• They believed the Earth was only a few thousand
  years old.
• Catastrophic events formed the Earth, created
  volcanoes, mountains, oceans, etc.

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Relative Dating

• Determines which comes first. Determining if rock
  layers are older or younger
• Compare them to undisturbed rock around the world

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Principle of Superposition

• A principle or rule that states that younger
  rocks lie above older rocks in un-disturbed
  sequences
• As you move from top of rock layers to the bottom
  the rock layers get older

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SUPERPOSITION
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Uplift

• movement within the Earth that moves rocks to the
  surface

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Unconformities

• Is a disturbance in the layer of a rock.
• Represents thousands, to millions of years in
  missing time in the layers of a rock
• Can be created through
• Erosion and weathering (p159, figure 4)
• Faulting- (earthquakes)
• Folding (anticlines, synclines, and monoclines)
• Tilting
• intrusion

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Rock Intrusion

• A layer of molten rock (hardened magma) from the
  Earths interior that squeezes into existing rock
  and then cools.
• Melts surrounding layers
• Interrupts the rock time scale.

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Types of Unconformities

• Disconformity part of a parallel rock layer is
  missing. (Layers may be eroded away and deposited
  elsewhere)
• Nonconformity- horizontal sedimentary rock
  layers lay on the eroded surface of intrusive
  igneous rocks or metamorphic rocks
• Angular unconformity- rocks are tilted or folded
  due to earthquakes or uplift (p 160)

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Terms

• Erosion
• Weathering
• Uplift
• Deforestation
• Mechanical weathering
• Chemical weathering

• Relative dating
• Uniformitarianism
• Superposition
• Intrusion
• Catastrophism
• Un-conformity
• Strip Mining
• Frost Wedging
• Abrasion