This is a picture of the Rock Cycle.
Igneous, Sedimentary, and Metamorphic rocks are the 3 major types of rocks. They are all formed by the Rock Cycle.
To the left, is a picture of Igneous, Sedimentary, and Metamorphic rocks.
http://kb-adventuresinhomeschooling.blogspot.com/2010_04_01_archive.html .
To the left, is a picture of Igneous, Sedimentary, and Metamorphic rocks.
http://kb-adventuresinhomeschooling.blogspot.com/2010_04_01_archive.html .
How do Igneous rocks form?
Igneous rocks form either above ground or underground. Underground, they are formed when magma deep within the Earth gets trapped inside small pockets. As they cool, they become Igneous Rocks. Igneous Rocks are also formed when volcanoes erupt. As the lava cools above ground, they become Igneous Rocks.
Intrusive Igneous Rocks are formed when magma cools and solidifies underground. Extrusive Igneous Rocks are formed at the crust as a result of partial melting of rocks within the mantle and the crust. Extrusive Igneous Rocks cool and solidify faster than intrusive igneous rocks, therefore, extrusive Igneous rocks are fine-grained.
http://library.thinkquest.org/05aug/00461/igneous.htm .
Intrusive Igneous Rocks are formed when magma cools and solidifies underground. Extrusive Igneous Rocks are formed at the crust as a result of partial melting of rocks within the mantle and the crust. Extrusive Igneous Rocks cool and solidify faster than intrusive igneous rocks, therefore, extrusive Igneous rocks are fine-grained.
http://library.thinkquest.org/05aug/00461/igneous.htm .
This is an extrusive igneous rock called Rhyolite
http://geology.com/rocks/igneous-rocks.shtml
http://geology.com/rocks/igneous-rocks.shtml
This is an intrusive igneous rock called Pegmatite.
http://geology.com/rocks/igneous-rocks.shtml
http://geology.com/rocks/igneous-rocks.shtml
How do Sedimentary rocks form?
Sedimentary rocks are formed by little pieces of Earth being broken down and worn away by wind and water. These little bits of Earth are washed downstream, where they settle on the bottom of rivers, lakes, and oceans. Layer after layer, eroded Earth is deposited onto each other. These layers are pressed down more and more through time, until the bottom layers become Sedimentary rocks. Organic Sedimentary Rocks are formed from the compaction and cementation of sediment, such as shells and partially decayed organisms. Clastic sedimentary rocks are formed from the compaction and cementation of rock
particles of various sizes which have been transported and deposited by the
processes of erosion. Examples of clastic sedimentary rocks are Shale,
Sandstone, Conglomerate, and Breccia. Chemical sedimentary rocks are formed by precipitation of water. Precipitation is when dissolved materials come out of water.
http://museumvictoria.com.au/melbournemuseum/discoverycentre/dynamic-earth/overview/sedimentary-environment/crystals-and-opals-in-sedimentary-rock/
particles of various sizes which have been transported and deposited by the
processes of erosion. Examples of clastic sedimentary rocks are Shale,
Sandstone, Conglomerate, and Breccia. Chemical sedimentary rocks are formed by precipitation of water. Precipitation is when dissolved materials come out of water.
http://museumvictoria.com.au/melbournemuseum/discoverycentre/dynamic-earth/overview/sedimentary-environment/crystals-and-opals-in-sedimentary-rock/
These are examples of Clastic Sedimentary rocks.
http://sarjeevansainbhi.webs.com/apps/photos/photo?photoid=136219417 .
http://sarjeevansainbhi.webs.com/apps/photos/photo?photoid=136219417 .
Coal is an example of an organic Sedimentary rock.
http://geology.com/rocks/sedimentary-rocks.shtml .
http://geology.com/rocks/sedimentary-rocks.shtml .
Halite (a.k.a Rock Salt) is a type of Chemical sedimentary rock.
http://geology.com/rocks/sedimentary-rocks.shtml .
http://geology.com/rocks/sedimentary-rocks.shtml .
How do Metamorphic rocks form?
Metamorphic rocks are formed when existing igneous or sedimentary rock is then
pushed into the earth and subjected to high heat and pressures. This then
changes its composition, which then becomes Metamorphic rock.
Some examples of Metamorphic rocks are Slate, Gniess, and Quartzite.
pushed into the earth and subjected to high heat and pressures. This then
changes its composition, which then becomes Metamorphic rock.
Some examples of Metamorphic rocks are Slate, Gniess, and Quartzite.
This is a type of Metamorphic rock called Slate. This rock is formed by the metamorphism of Shale, a sedimentary rock.
http://geology.com/rocks/metamorphic-rocks.shtml .
http://geology.com/rocks/metamorphic-rocks.shtml .
This is another type of Metamorphic rock called Gneiss.
http://geology.com/rocks/metamorphic-rocks.shtml .
http://geology.com/rocks/metamorphic-rocks.shtml .
Textures for each rock
Fine-grained, Coarse-grained, and Glassy are the most common textures for rocks.
Rocks become fine-grained because they cool rapidly, like Chert, a sedimentary rock, that is fine-grained.
http://www.geologyclass.org/sedimentary_concepts_files/image016.jpg
http://www.geologyclass.org/sedimentary_concepts_files/image016.jpg
Rocks become coarse-grained because they cool very slowly, like Granite, a coarse-grained igneous rock.
http://www.ux1.eiu.edu/~cfjps/1300/cg_granite.jpg
http://www.ux1.eiu.edu/~cfjps/1300/cg_granite.jpg
Rocks become glassy when lava or magma cools extremely quick, even quicker than fine-grained rocks. The quick cooling doesn't allow time for crystallization, which results in the formation of natural glass.
http://www.oregongeology.org/sub/learnmore/jpegs/orig/obsidian.jpg
http://www.oregongeology.org/sub/learnmore/jpegs/orig/obsidian.jpg
Glossary
Cementation~The heating of 2 substances in contact in order to effect some change in one of them,especially, the formation of steel by heating iron in powdered charcoal.
Clastic~Noting or pertaining to rock or rocks composed of fragments or particles of older rocks or previously existing solid matter.
Chemical~A substance produced by or used in a chemical process.
Coarse-grained~Having a coarse texture or grain. Compaction~The consolidation of sediments resulting from the weight of overlying deposits.
Decayed~To become decomposed;rot.
Eroded~To eat into or away.
Fine Grained~Being of fine grain or texture
Igneous Rock~Rocks formed by the cooling and solidifying of molten materials.
Metamorphic Rock~Rock that was once one form of rock but has changed to another under the influence of heat,pressure, or some other agent without passing through a liquid phase.
Organic~Characteristic of, pertaining to, or derived from living organisms.
Rock Cycle~A continuous process by which rocks are created, changed from one form to another, destroyed, and then formed again.
Sediment~Mineral or organic matter deposited by water, air, or ice.
Sedimentary Rock~Rock that has formed through the deposition and solidification of sediment, especially sediment transported by water, ice, and wind.
Texture~The visual and especially tactile quality of a surface.
Clastic~Noting or pertaining to rock or rocks composed of fragments or particles of older rocks or previously existing solid matter.
Chemical~A substance produced by or used in a chemical process.
Coarse-grained~Having a coarse texture or grain. Compaction~The consolidation of sediments resulting from the weight of overlying deposits.
Decayed~To become decomposed;rot.
Eroded~To eat into or away.
Fine Grained~Being of fine grain or texture
Igneous Rock~Rocks formed by the cooling and solidifying of molten materials.
Metamorphic Rock~Rock that was once one form of rock but has changed to another under the influence of heat,pressure, or some other agent without passing through a liquid phase.
Organic~Characteristic of, pertaining to, or derived from living organisms.
Rock Cycle~A continuous process by which rocks are created, changed from one form to another, destroyed, and then formed again.
Sediment~Mineral or organic matter deposited by water, air, or ice.
Sedimentary Rock~Rock that has formed through the deposition and solidification of sediment, especially sediment transported by water, ice, and wind.
Texture~The visual and especially tactile quality of a surface.