Starring Sedimentary, Igneous and Metamorphic Rock Rockin’ the Rock Cycle Starring Sedimentary, Igneous and Metamorphic Rock

The Rock Cycle is a continuous process where any type of rock can be changed into any other type of rock.

What are Rocks? Rocks: naturally occurring solids that are made of two or more minerals There are three types of rocks based on how they are formed on Earth: Igneous Sedimentary Metamorphic Granite - Igneous Marble - Metamorphic Shale - Sedimentary

The Rock Cycle Rocks are constantly being made and recycled to form other types of rocks. This is called the Rock Cycle. You can start at any place and follow the life of a rock. We will start with igneous rock.

What Size Grains does it have? Igneous Rock Igneous rock is made when magma cools and crystallizes. (Igneous means “from fire or heat”) Type of Igneous Rock Where does it Form? How does it Cool? What Size Grains does it have? Example Intrusive Inside Earth Slowly Large (Course) Granite Extrusive Outside Earth Quickly Small (Fine) or Glassy (Very Fine) Basalt Obsidian

Examples of Igneous Rock Granite: Large/Course Grains Basalt: Small/Fine Grains Obsidian: Glassy/Very Fine Grains

What Type of Igneous Rock?? A. B. C. D.

What can happen to the Igneous Rock? 1. It can be weathered and eroded and turned into small pieces, called sediment, which can then be turned into a sedimentary rock. 2. It can be put under high heat or pressure and form a metamorphic rock. Could melt and become magma again = igneous rock  We will move to sedimentary rocks next!

Becoming a Sedimentary Rock Weathering is the breaking down of rock on Earth’s surface physically or chemically Physical Weathering: Breaks rock into smaller pieces. Examples- Tree Roots breaking apart rocks, Water freezing inside cracks of rocks causing them to expand and break Chemical Weathering: Involves chemical reactions that change the rock. Example- Acid Rain on gravestones (dissolves minerals)

Rock is weathered and forms sediments Sediments: smaller pieces of rock Examples: Gravel, Sand, Mud, Soil

Becoming a Sedimentary Rock Erosion – sediments are transported by wind or water 3. Deposition – when the sediments stop moving. This produces different types of “bedding”

3. Deposition – Types of Bedding Bedding – oldest sediments on the bottom, youngest sediments on top 2. Graded Bedding – biggest sediments on bottom, smallest on top (happens in water) 3. Cross Bedding – sediments are laid at an angle (ex: sand dunes)

Finally Becoming a Sedimentary Rock! 4. Lithification - Sediments must be buried, compacted, cemented together to make a sedimentary rock. Examples of Sedimentary Rock: Coal Sandstone Shale

Where We’ve Been…

What can happen to Sedimentary Rock? 1. Could weather and erode to become sediments = sedimentary rock 2. It can be put under high heat or pressure and form a metamorphic rock. Could melt to form magma = igneous rock  We will move to metamorphic rocks next!!

Metamorphic Rocks Formed from existing rocks. Are created by intense heat or intense pressure. Can be foliated = looks like it has layers (made from pressure) Can be non-foliated = does not look like it has layers (made from heat)

Examples of Metamorphic Rock Limestone (Sedimentary)  Marble Shale (Sedimentary)  Slate Granite (Igneous)  Gneiss

What can happen to Metamorphic Rock? Could weather and erode to become sediments = sedimentary rocks 2. Could melt to form magma = igneous rocks

In Summary… The Rock Cycle is the continuous making and remaking of rocks All rocks can become other types of rocks The three types of rocks are: Igneous, Sedimentary, and Metamorphic Igneous Rocks are made by magma Sedimentary Rocks are made by sediments Metamorphic Rocks are rocks exposed to heat or pressure Interactive Rock Cycle

The Importance of Rocks Granite (I) is widely used in homes and buildings and is the “state rock” of N.C. Marble (M) makes up the Lincoln Memorial and is used in flooring Limestone (S) is used in construction The State Capitol Building is made of Gneiss (M) Coal (S) is an energy source