Rock Formation

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Rock Formation
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• Introduction
• A. Rocks are composed of one or more minerals.
• 1. The minerals are composed of a combination
  of the 8 most common elements on earth.
• A. Oxygen E. Calcium
• B. Silicon F. Sodium
• C. Aluminum G. Potassium
• D. Iron H. Magnesium
• B. The Earths crust and surface are made of
  rocks that are either igneous, sedimentary, or
  metamorphic.
• II. Igneous Rock
• A. Rocks that are formed when hot molten
  (liquid) rock hardens
• B. There are 2 types of igneous rocks
• 1- Plutonic Rock
• A formed when hot liquid rock hardens under
  the surface of the earth.
• B- A.K.A. intrusive rock.

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2- Volcanic Rock A. formed when hot liquid
rock does not harden until it reaches the
surface of the earth. B. A.K.A. Extrusive
rock. C. There are two types of texture 1-
coarse grained- which are large crystals that
form when the rock cools slowly. 2- fine
grained- small crystals formed when the rock
cools quickly. D. Color is a Reflection of
Mineral Content. E. Examples of Igneous Rock
(Type 1) 1- Granite A. most common B.
most important rock making up the
continents. C. quarried in N.C. used as
building materials. D. used for curbing,
paving, and tombstones. 2- Basalt A. fine
grained B. found beneath the Ocean floor
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• 3. Obsidian
• A. a.k.a. volcanic glass
• B. cools very quickly
• 4. Pumice
• A. Fine grain with many holes
• B. Spongy look light enough to float in water
• 5. Scoria
• A. fine grained about 50 holes
• B. used in the bottom of gas grills to hold
  heat for faster cooking.

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(Type 2) Metamorphic Rock

• Formed deep within the earths crust.
• Tremendous pressure and heat cause igneous and
  sedimentary rock to undergo major changes.
• Example
• 1- Marble
• A. formed when limestone is exposed to enough
  heat and pressure to change its internal crystal
  structure.
• B. Used to cover buildings.
• 2- Gneiss
• A. formed when granite or sedimentary rock is
  exposed to enough heat and pressure.
• 3- Slate
• A. formed when a sedimentary rock such as shale
  is exposed to enough pressure and heat.
• B. used to make roofing tiles and old fashion
  tile floors.

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(Type 3) Sedimentary Rock

• Formed from sediment
• 3 Basic Groups (classified by the way they are
  formed).
• 1. Fragmental rock (adjective) clastic
• A. Formed from pieces of fragments of larger
  rocs.
• B. Fragments or pieces are carried by running
  water and deposited as sand, clay, or gravel.
• C. Fragments are deposited layer after layer
  causing tremendous pressure by gravity and
  weight from other rocks.
• 2. Examples
• A. Sandstone
• 1. Some are porous and can store large
  amounts of water in them, that lay
  underground, their called aquiferous.
  Aquifers are important sources of groundwater.
• B. Conglomerate

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• C. Shale
• 1. formed from fine grained particles.
• 2. common source of fossil remains.
• 2. Evaporites (adjective) chemical
• A. formed when the dissolved chemicals in water
  form crystals as the water slowly evaporates.
• B. Examples
• 1- Halite- rock salt
• 2- Gypsum- used to make chalk dry wall
• 3- Limestone- Used to produce concrete for
  streets, bridges, and highways.
• 3. Organic Sedimentary Rocks (adjective)
• A. Made from remains of once living organisms.
• B. Examples
• 1- Limestone- often contains a quartz like
  crystal (flint).
• used to make arrow heads ignite gun powder.
• 2- Chalk- from microscopic remains of organisms
  called foraminifera.

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• 3. Coal- Made from plant remains in swamp
  bottoms millions of years ago. Most abundant
  fossil fuel in the U.S.A.