Download Types of Rocks

Types of Rocks
Warm-Up:
1. Explain how rocks can be formed?
2. What is the rock cycle?
Warm-Up:
Describe the texture and composition of
the two igneous rocks.
A
B
How to Classify a Rock
Rock - A naturally occurring, solid, mixture of one or more minerals or
organic matter
3 Groups (based on formation):
igneous, sedimentary, and metamorphic
Texture and composition give clues as to how rocks are formed, and
are used to classify rocks
Composition – the type of material a rock contains
Texture – the size, shape and arrangement of the
minerals/particles that make up a rock.
Rocks are always changing form in a cycle called the Rock Cycle
Web Links
(also found on my website)
Rock Cycle Interactive
http://www.learner.org/interactives/rockcycl
e/index.html
Rock Cycle Animations
http://www.classzone.com/books/ea
rth_science/terc/content/investigations/e
s0602/es0602page02.cfm
Igneous Rocks
Extrusive rocks- formed by cooling lava
Texture:
• glassy (obsidian)
• porous (pumice)
• fine-grained (basalt)
Intrusive rocks- formed by cooling
magma
Texture:
• coarse-grained (granite)
Formation of Extrusive Igneous Rock
Extrusive Igneous Rock
Formation of Intrusive Igneous Rock
Intrusive Igneous Rock
Yosemite
N.P.
Obsidian…
Basalt…
Granite…
Course
Grained
Texture
Pumice…
Porous Texture
Sedimentary Rocks
Formed by:
Weathering (breaking down of rock)
Examples of Weathering
Mechanical Weathering
Root Action
Frost Action
Moss
Examples of Weathering
Chemical Weathering: Oxidation (rock exterior)
Sedimentary Rocks
Formed by:
Weathering (breaking down of rock)
Erosion (movement of sediments)
Five Agents of Erosion
Gravity (Mass wasting)
Gravity (Mass Wasting)
Soil creep
Slumping
Five Agents of Erosion
Gravity (Mass wasting)
Wind
Wind
Five Agents of Erosion
Gravity (Mass wasting)
Wind
Running water
Running Water
Niagara Falls
Yellowstone
Canyon & River
Five Agents of Erosion
Gravity (Mass wasting)
Wind
Running water
Glaciers
Glaciers
Five Agents of Erosion
Gravity (Mass wasting)
Wind
Running water
Glaciers
Waves
Waves
Australia
Five Agents of Erosion
Gravity (Mass wasting)
Wind
Running water
Glaciers
Waves
Sedimentary Rocks
Formed by:
Weathering (breaking down of rock)
Erosion (movement of sediments)
Deposition (collection of sediments)
Examples of Deposition
Nile River
Delta
Lateral moraine
Cape Cod
(spit)
Sedimentary Rocks
Formed by:
Weathering (breaking down of rock)
Erosion (movement of sediments)
Deposition (collection of sediments)
Compaction & Cementation
Compaction & Cementation
Sedimentary Rocks (categorized by composition)
Clastic Rocks (rock fragments)
• Conglomerates (pebbles)
• Sandstones (sand)
• Shales (mud & clay)
Organic Rocks (once living)
• Ex: limestone(coral and shells), coal (plants)
Chemical Rocks (evaporation)
• Ex: rock salt, limestone, geodes, gypsum
Clastic Sedimentary Rock…
Conglomerate
Shale
Sandstone
Organic Sedimentary Rocks…
Coal (plant mateiral)
Limestone (shell & coral)
Chemical Sedimentary Rocks…
Gypsum rock
Limestone
Geode
Metamorphic Rocks
Formed by tremendous heat & pressure,
and chemical reactions inside the crust.
Formed from all three rock types.
Types of Metamorphic Rock
Slate
Foliated (bands or layers)
Ex: schist, slate, gneiss
Gneiss
Foliated texture
Types of Metamorphic Rock
Unfoliated (no bands or layers)
Ex: marble and quartzite
Quartzite
Compaction &
Cementation
Sedimentary
Rocks
Sediments
W.E.D.
W.E.D.
W.E.D.
Igneous
Rocks
Heat Pressure
Heat Pressure
Metamorphic
Rocks
W.E.D. = Weathering,
Erosion, & Deposition
Magma &
Lava
Melting
Cooling
Closure:
Describe the texture and composition of
the two igneous rocks.
A
B
Warm-up / Closure:
1. In igneous rocks how is cooling rate and
crystal size related?
2. Which rock type would you have the
best chance of finding a fossil? Why?