Rock Classification
by Renzo Pena-Perez
Rock
Rocks are the solid material forming part of the surface of the earth and other similar planets, exposed on the surface or underlying the soil or oceans.
Igneous Rocks
Formed by cooling and crystallization of molten rock (600 degrees - 1000 degrees)
Magma- molten material inside the Earth's lithosphere
Lava- molten material at or above the Earth's surface
Due to the way igneous are formed they appear to have crystals without any apparent layering
Solidification- Liquid to solid
Sedimentary Rocks
Most sedimentary rocks are composed primarily of the weathered (broken) remains of other rocks. Sedimentary rocks usually formed by the compaction (adding pressure) and cementing of sediments.
Sediments are rock fragments
Sedimentary rocks are commonly found at or near the Earth's surface.
Sedimentary rocks are the only type of rock that contains fossils.
Metamorphic Rocks
Metamorphic rocks form when other rocks are exposed to heat and pressure without melting. Foliation is the alignment of minerals in a metamorphic rock. The texture is folded.
Diorite
Is an igneous rock. They are formed intrusively in volcanoes. Composed of 57% of Plagioclase Feldspar, 12% biotite black, and 31% Amphibole. The crystals are 1mm to 10mm. It is vesicular.
Dolostone
Is a sedimentary rock. Chemically or inorganically formed. It is crystalline and has a grain size of fine to coarse crystals It has a composition of dolomite.
Marble
Is a metamorphic rock. Marble is non foliated. The grain size is fine to coarse. It is composed of calcite or dormite . The type of metamorphism is regional or contact.
The Rock Cycle
Is a model showing how rocks and sediments change over time. There are external and internal processes. Internal occur within the earth and external occur on the earth's suraface