The Rock Cycle
This page will tell us about how rocks form. It will also tell us about Igneous rocks, sedimentary rocks, and metamorphic rocks.
(http://imnh.isu.edu/digitalatlas/geo/basics/diagrams.htm)
The rock cycle is a series of processes earth's surface inside the planet that that slowly changes rocks from one kind kind to another. Earth's constructive and destructive forces -- including plate tectonics -- move rocks through the rock cycle. The rock cycle can follow many different pathways. You can follow the rock of Stone Mountain along one of the pathways of the rock cycle.
Types of rocks
Igneous Rocks
Igneous rocks form when they are under ground they are formed when magma deep within the Earth becomes trapped in small pockets. As these pockets of magma cool slowly underground, the magma becomes an igneous rocks. (://www.google.com/search?q=how+do+igneous+rocks+form&oq=how+do+ign&aqs=c) (http://www.geoprime.com/10_large_igneous_rocks_samples_i.htm)
|
Sedimentary Rocks
Sedimentary rocks are formed when sediment is deposited out of air, ice, wind, gravity, or water flows carrying the particles in suspension. This sediment is often formed when weathering and erosion break down a rock into loose material in a source area. (https://www.google.com/#q=how+do+sedimentary+rocks+form) (http://canarygeog.canaryzoo.com/Rocks%20Rocks.htm)
|
Metamorphic Rocks
A metamorphic rock is formed when pre-existing rocks are subjected to elevated temperatures or pressure. The elevated temperatures or pressure causes the rock to recrystallize and to form a coarser grained rock. (http://www.ask.com/question/how-is-metamorphic-rock-formed) (http://library.thinkquest.org/05aug/00461/meta.htm)
|
The Three Types Of Sedimentary Rocks
The three types of sedimentary rocks are clastic rock, organic rock, and chemical rocks.
Clastic sedimentary rocks are sedimentary rocks formed out of broken down bits of rocks. There are several kinds of clastic sedimentary rocks; they are categorized by the size and sometimes the shape of the pieces that make up the rock. The kinds of clastic sedimentary rocks are called: Conglomerates, breccias, sandstone, mudstone, siltstone.
(http://www.kidsgeo.com/geology-for-kids/0027C-sedimentary-rocks.php)
All organic rocks are formed by living organisms. Animals produce limestone from calcium carbonate, which is the mineral calcite. They create shells for protection by extracting the calcium carbonate from seawater and turning it into limestone shells.
(http://www.kids-fun-science.com/organic-rocks.html)
(http://www.kids-fun-science.com/organic-rocks.html)
Chemical sedimentary rocks are rocks that are not made up of sediment but of mineral crystals made from elements that have been dissolved in water.(http://www.ask.com/question/what-are-chemical-sedimentary-rocks)
The Textures Of Rocks
Coarse grained texture is rough texture. The picture is an example of coarse grained rock. Fine grained texture is basically the opposite of of coarse grained texture, It is smooth and not rough.
(https://www.google.com/search?q=rock+textures&source=lnms&tbm=isch&sa=X&ei=JL3nUt-CGJG_sQSksYKABg&ved=0CAcQ_AUoAQ&biw=800&bih=509#facrc=_&imgdii=_&imgrc=VPpxV1srsTXOsM%253A%3BmSfoO2TyIQ014M%3Bhttp%253A%252F%252Farsgrafik.s3.amazonaws.com%252Fuploads%252F2009%252F10%252Fstone3.jpg%3Bhttp%253A%252F%252Fwww.arsgrafik.com%252Ffree-background-texture-rock-no-3%252F%3B2700%3B1793)
(https://www.google.com/search?q=rock+textures&source=lnms&tbm=isch&sa=X&ei=JL3nUt-CGJG_sQSksYKABg&ved=0CAcQ_AUoAQ&biw=800&bih=509#facrc=_&imgdii=_&imgrc=VPpxV1srsTXOsM%253A%3BmSfoO2TyIQ014M%3Bhttp%253A%252F%252Farsgrafik.s3.amazonaws.com%252Fuploads%252F2009%252F10%252Fstone3.jpg%3Bhttp%253A%252F%252Fwww.arsgrafik.com%252Ffree-background-texture-rock-no-3%252F%3B2700%3B1793)
Compaction And Cementation
Compaction is the process that presses sediments together. Year after year more sediment falls on top, creating new layers. The weight of the layers further compacts the sediment, squeezing them tightly together. The layers often remain visible in the sedimentary rock.
Cementation is the process which dissolved minerals crystallize and glue particles of sediment together. It often takes millions of years for compaction and cementation to transform loose sediments into solid sedimentary rock.