Rocks and the Rock Cycle

L15: Bell Ringer and Quick Write

1/23/15 Bell Ringer: What is the rock cycle?

Quick Write: What is a rock and how is it formed?

1/27/15 Bell Ringer: How is a rock different than a mineral?

Quick Write Answer:

A rock is a solid aggregate made up of one or more minerals.

Title ALL your pages

R14: Unit 2 Geology (cover page)L15: Bell Ringer and Quick WriteR15: Types of RockL16: Igneous RockR16: Metamorphic RockL17: Sedimentary RockR17: Rocks vs. Minerals L18: What is a mineral? R18: Mighty Mineral- Worksheet L19: Mighty Mineral Poster

R15: Types of Rock

Set up your foldable!

Sedimentary– BrownIgneous- OrangeMetamorphic- Red

Cut it out as ONE piece, THEN cut your slits

L16: Igneous Rock

Cut out Title (Igneous)

Cut out Types of Igneous Rocks Box (it should be ONE piece)

Extrusive– GreenBoth- Blue Intrusive- Brown

R16: Metamorphic Roc

Color Title

Non-foliated – Red

Both– Orange

Foliated-- Yellow

L17: Sedimentary

Color title

Clastic- purple

Chemical- pink

Organic– blue

Three Types of Rocks

• Rocks are classified by how they form– Igneous– Sedimentary– Metamorphic

– Rocks can change from one type to another over time

Schist

Rock Classification

• Rocks are classified by:– How they form– Texture– Grain size– Mineral

composition

Conglomerate Sedimentary Rock

Igneous Rocks

• Igneous rock: forms when molten rock (magma) cools and hardens

• Classified by:– Where they form – Crystal (grain) size

Basalt

L16: Intrusive Igneous Rock

• Intrusive igneous: • cooling takes place

slowly beneath Earth’s surface

• Medium to coarse grained

• Example: Granite granite

Extrusive Igneous Rock

• Extrusive igneous:• cooling takes place

rapidly on Earth’s surface

• Crystals form but don’t have time to grow

• -fine grained • Example: Basalt,

Pumice

Pumice

Igneous Rock

Both:

Forms when magma cools

Grain size depends on how much time it had to cool

Sedimentary Rock

• Sedimentary rock: forms from the compaction and/or cementation of sediments

• This process is called lithification

• Sediments are:– Rock pieces– Mineral grains– Shell fragments

Limestone

How do sediments form?

• Sediments form through the processes of weathering and erosion of rocks exposed at Earth’s surface

weathering

erosion

Sedimentary Rock con’t….

• Sedimentary rock can also form from the chemical depositing of materials that were once dissolved in water

• When water evaporates, minerals are left behind and form rock

gypsum

Metamorphic Rock

• Metamorphic rock: forms when any rock type is changed into a different kind of rock

• Changes due to great heat and/or pressure Gneiss

Metamorphic Rock

Foliated:

Repetitive layering in rocks caused by pressure pushing in different sections of the rock in different directions

(Examples: Slate, Gneiss and Schist)

Metamorphic

• Non-foliated:

Rocks don’t show layering and often made up of a single material

-Example: Marble, Quartzite, Anthracite)

Metamorphic

Both:

Original rock is exposed to heat and pressure which causes physical & chemical changes

How does a rock change?

• Rocks are heated, squeezed, folded, or chemically changed by contact with hot fluids

marble

L17: Sedimentary Lithification: loose sediment is converted to a solid rock

Over time rock becomes weathered and is converted to clay, sand, gravel and sometimes becomes dissolved in water

Sedimentary

Clastic:

-particles of weathered rock (gravel, sand, silt, clay)

-85% of sedimentary rock is Clastic

Sedimentary

Chemical:

-created by chemical weathering/precipitation from minerals

-Example: Rock salt forms when salt precipitates from evaporating sea water

Sedimentary

• Organic: – Lithified remains of

plants and animals

Example: Coal (decomposed and compacted plan remains)

Rocks vs. Mineral

• Rock: – Naturally occurring

aggregate of minerals

– Don’t have a definite chemical composition

Rock Vs. Mineral

• Mineral: – Naturally occurring

substance formed through geological processes

– Have a definite chemical composition

Rocks Vs. Minerals

• Both:– Found in Earth’s

crust – Commercial value

(can be sold)

L18: What is a mineral?

Color:

Solid– Brown

Inorganic– Blue

Formed in Nature– Green

Crystalline– Yellow

The Rock Cycle

The Earth Recycles Rock

• The rock cycle is an ongoing series of processes inside Earth and on the surface

• Slowly changes rocks from one kind to another

• Any type of rock can change into another type

How does this relate to plate tectonics?

• Plate movement drives the rock cycle– Subduction (1 plate

pushed under another plate)

• Re-melts rock into magma

– Mountain building• Folding, faulting, uplift• Exposes rock at the

surface to be weathered and eroded

a. Cementation and compaction (lithification)

b. Heat and pressure

c. Weathering, transportation(erosion), and deposition

d. Cooling and solidification

e. Melting

Rocks/Rock Cycle Foldable

• Your foldable should include the following:

1.Name of each rock type2.How each rock type

formed3.A brief description of rock

type4.At least 2 examples of

each rock type5.Illustrate 1 example for

each rock type

Copy Me

Based on the processes shown in the diagram, which type of rock is formed at #1?   A. Sedimentary B. Igneous C. MetamorphicD. Clastic  

 

  

Because heat and pressure are needed to form #3, it must be what type of rock? A.     SedimentaryB.     IgneousC.     MetamorphicD.     Clastic