RocksGroup5

Igneous Rock : [] ► how they are formed: inside volcanos under the earth (in magma), minerals are formed and the heat and pressure compact them together, making igneous rock. ►how they are broken down: erosion,deposition, cementation, melting and cooling. ►there are two different types of igneous rocks. intrusive and extrusive. - intrusive rocks are rocks that are form and crystallize inside the earth. for example, gabbro was formed in magma (molten rock inside the earth), there for it is an intrusive rocks. - extrusive rocks are rocks that are formed outside the earth. for example, Rhyolite is formed in Lava (molten rock outside of the earth), there for it is an extrusive rock. ► you can identify an Igneous rock by observing its __ texture __. Texture is the size, shape, distribution of the crystals or crains of crystals. - coarse texture (formed deep inside the volcano) - Fine texture (formed toward the top of the volcano) - Glassy texture (formed on the very top of the volcano)

Sedimentary Rock : ►Sedimentary rocks are formed when weather and erosion produces sediments. -Water -Wind -Glacures -Gravity ► Clasic rocks are formed from solid fragments of other rocks. ► Chemical (Crystalline) sedimentary rocks are formed from the precipitation of minerals out of solution. ► Organic (Bioclasic) sedimentary rocks are formed from the remains of living things or rocks. ►Sedimentary rocks contain fosils, many animals accumulate and die where sedimentary rocks are formed. te sediments allow the fossils to be formed and preserved. *SeDiMeNtArY rOcKs ArE tHe OnLy RoCkS tHaT cOnTaIn FoSsILs*

Metamorphic Rock : http://geology.com/rocks/metamorphic-rocks.shtml ► Regional - regional metamorphism is when metamorphic rocks are formed over a LARGE region. for example, the rocky mountains ►A parent rock is the rock which becomes metamorphosed. ►Metamorphism is the process of the mineral crystals or changing the mineral composition **__without melting.__** ►Foliation is parallel layers of minerals caused by pressures on the rock. -- when large areas of rock are under intense hear and pressure causing them to change form. ►Contact Metamorphism is when hot magma intrudes into overlaying rocks. ►Dynamic Metamorphism is when the heat deformes the rock.

Rock Cycle - ►the rock cycle is an easy way to explain how every rock is formed from eachother, and how it is broken down. all of the three rocks can turn into one another. for example, igneous rocks can be formed into both sedimentary rocks and metamorphic rocks. for an igneous rock to turn into a medamorphic rock, it undergoes heat and/or pressure, and metamorphism. you can tell just by looking at the diagram above. the arrows show how each rock is fromed from the other, and broken down.