Rocks and Soil

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Rocks and Soil
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Rocks

• ROCKS
• The rocks you see around you - the mountains,
  canyons riverbeds, are all made of minerals. A
  rock is made up of 2 or more minerals. Think of
  a chocolate chip cookie as a rock. The cookie is
  made of flour, butter, sugar chocolate. The
  cookie is like a rock and the flour, butter,
  sugar chocolate are like minerals. You need
  minerals to make rocks, but you don't need rocks
  to make minerals. All rocks are made of minerals.

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Rocks

• Properties of Rocks (how we categorize them)
• Texture
• Layering
• Color

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Texture

• How smooth or rough they are
• http//www.classzone.com/books/earth_science/terc/
  content/investigations/es0603/es0603page02.cfm

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Layering

• http//www.classzone.com/books/earth_science/terc/
  content/investigations/es0610/es0610page04.cfm

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3 types of rocks

• Igneous Rocks
• Metamorphic Rocks
• Sedimentary Rocks

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Igneous Rocks

• Igneous rocks form directly from the cooling of
  magma.
• http//www.fi.edu/fellows/fellow1/oct98/create/ign
  eous.htm

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Metamorphic Rocks

• The metamorphic rock gets the name from "meta"
  (change) and "morph" (form).
• The rock is moved into an environment in which
  the minerals which make up the rock become
  unstable. In most cases, this involves burial
  which leads to a rise in temperature and
  pressure.
• http//www.fi.edu/fellows/fellow1/oct98/create/met
  amorph.htm

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Sedimentary Rocks

• In most places on the surface, the igneous rocks
  which make up the majority of the crust are
  covered by a thin layer of loose sediment, and
  the rock which is made as layers of this debris
  get compacted and cemented together.
• http//www.fi.edu/fellows/fellow1/oct98/create/sed
  iment.htm

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Rock Cycle

• http//www.classzone.com/books/earth_science/terc/
  content/investigations/es0602/es0602page02.cfm

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• Smaller rocks come from the breakdown of larger
  rocks through the action of plants and weathering

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• Soil

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Composition

• Soil is made of
• Small rocks
• Decomposed pieces of plants and animals
• Dead plants
• Dead animals
• Products of plants and animals
• Animal waste

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Properties of Soil

• Color
• Is it dark or light?
• Capacity to retain water
• Does it hold a lot of water?
• Capacity to grow plants
• Does the soil have nutrients like nitrogen to
  help plants grow well?
• Texture
• How does it feel?

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Kind of soil How it feels Hold shape when wet
Sandy Feels gritty Wont stick together when wet
Silty Feels powdery Will stick together when wet but will not hold together after it dries
Clay Feels sticky Stays together when wet
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Which is clay? Which is sand?
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• Soil is also found in layers like rocks, with
  topsoil on top.
• Each layer is called a horizon
• http//www.classzone.com/books/earth_science/terc/
  content/investigations/es1206/es1206page02.cfm?cha
  pter_noinvestigation