Classification Of Rocks

• Igneous rocks are formed from the solidification or cooling of molten rock through crystallization.
• Sedimentary rocks form when sediments accumulate, compact, and cement together over time. Fossils found.
• Metamorphic rocks result from changes to existing rocks due to heat, pressure, or chemical reactions.
• Contact Metamorphism - The process of the melting of rocks due to the heat of magma. (Contact with magma)
• Regional Metamorphism - The process of changing the composition of rocks in a region.
• Extrusive/Volcanic rock forms - when magma makes its way to Earth's surface as lava and then cools. The crystals are very small (fine-grained) since the cooling process is fast.
• Intrusive/Plutonic - It cools slowly beneath the Earth surface and are created by magma. The intrusive igneous rocks have very large crystals (coarse grained).
• Composition - it refers to rock's mineral and chemical make-up
• Felsic - igneous rocks that are light in colors; feldspar and silicates
• Mafic - dark-colored igneous rocks made up of magnesium, calcium and iron
• Intermediate - refers to igneous rocks between mafic and felsic composition
• Ultramafic - denotes that igneous rocks composed chiefly of mafic minerals
• Texture - overall appearance of a rock based on the size, shape, and arrangement of interlocking mineral crystals