Rock and Roll
Igneous,sedimentary and metamorphic
Metamorphic rock have been changed over time by extreme pressure and heat.They are formed by pressure deep under earths surface from extreme heat caused by magma or by the intense collisions and friction of tectonic plates.Marble, is a metamorphic rock that is formed by the sedementary limestone.The metamorphic rock gets its name from ''Meta'' and ''Morph.''Common metamorphic rocks include slate,schist,gneiss, and marble.
Sedimentary rocks are often called secondary, because they are often the result of the accumulation of small pieces broken off of pre-existing rocks. Sedimentary rocks are formed by sediment that is deposited over time, usually as layers at the bottom of lakes and oceans.Chalk is a soft, white form of limestone.Flint is a hard, sedimentary form of the mineral quartz.
Igneous rocks are crystalline solids which form directly from the cooling of magma.The earth is made of igneous rock -at least at the surface where our planet is exposed to the coldness of space.Igneous rocks are given names based upon two things:those two things are composition (what they are made of)and texture(how big the crystals are).