ENVS 101 1st Edition Lecture 6 Outline of Last Lecture I. Introduction to Materials of the EarthII. Organic Matter of the EarthIII. Composition and Internal Structure of the EarthIV. Introduction to MineralsOutline of Current Lecture II. Silicate Structures/ Contents of common MineralsIII. Properties to classify Igneous RockIV. From Rock to Magma and Back againV. From Rock to RegolithVI. Overview of Sediment FamiliesCurrent LectureThe most common mineral group: Silicates, which contain Silicone (Si) and Oxygen (O) other mineral groups include: oxides, sulfides, carbonates, sulfates, phosphates, and halides*Silicone and Oxygen are the most common elements found within the Earth’s crust, and elements are often oxidized once they come into contact with oxygen, ex: copper oxide, the greenish color that is found on the Statue of Liberty is a popular example of this particular oxidation. *All mineral groups, except for halides, have oxygen within their structure. Silicates- Feldspars: Make up 60% of the minerals in the Earth’s crust- Quartz: Make up 15% of the minerals in the Earth’s crust- Other: Make up 20% of minerals in the Earth’s crustThis limits non-silicone to only 5% of the Earth’s crust overall!There are three types of Silicate Structures:- Single Tetrahedra, Sheets, and Framework These notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Biotite is an example of a sheet mineral. It’s layers are so weekly bonded that it flakes, and the sheet layers can be ripped apart very easily. It contains Potassium (K), Magnesium (Mg), and Iron (Fe) and is an aluminosilicate. Since it is dark colored, it is mafic.An example of a chain mineral is Augite, an aluminosilicate containing Calcium (Ca), Iron (Fe), Sodium (Na), and Magnesium (Mg). Since it is dark in color, it is mafic. An example of a Framework mineral is Orthoclase feldspar, or “K-Spar” (potassium aluminosilicate). Since it is light in color, it is considered felsic, rather than mafic.Granite (Igneous Rock), contains Quartz, Potassium Feldspar, and biotite. The Sandia Mountains are primarily comprised of feldspar.The crystal structure of minerals can greatly affect another particular categorization of minerals:their hardness. For example, Graphite (found in our pencils) is pure carbon, and it is a sheet mineral, its hardness is about 1.5 in scale. The diamond, by contrast, is a framework mineral and has a hardness of 10 in scale. The diamond is actually the hardest substance that is found on the Earth.An interesting natural occurrence of dissolved minerals can be found in the world famous WhiteSands, which are dunes that are actually comprised of dissolved gypsum!An example of a rock that is not actually a mineral is the fire opal, which has no actual crystal structure, but rather, a very orderly packing of tiny silica spheres within its structure.*Be sure to copy down Rock Cycle diagrams from TextbookIgneous Rocks: Are classified by two properties- By their Composition: High Silica (SiO2) rocks are called felsic, and rocks with low Silica are mafic.- Texture in the size and Arrangement of the Crystals: Fine grained rocks have small crystals, whereas coarse grained rocks have larger, mostly visible crystals.From Rock to Magma and Back Again:Rapid cooling results in volcanic rock, which characteristically have very fine grained structure, because lava cools so quickly that minerals do not have time to grow large. In fact, some lava cools fast enough to form glass. Pyroclastic rock is transitional between igneous and sedimentary rock, forming tephra. Tuff is formed by volcanic ash.- Slow cooling: plutonic/intrusive rockIntrusive igneous rock tends to be coarse grained, because magma cools at a slower rate within the crust and has more time to form crystals.- Pegmatite: Extremely coarse-grained rock.- Porphyry: A mixture of both small and large grains.Weathering processes physically break apart and chemically alter rocks that are exposed to the effects of the atmosphere and the hydrosphere:- Physical/Mechanical weathering: Is the physical disintegration of the rock resulting frompressure reduction, frost wedging, salt wedging, fire, solar heating, and plant roots.- Chemical weathering: Consists of the alteration of mineral and chemical composition of rocks by dissolution and other chemical reactions- As physical weathering breaks rock apart, the surface area in turn increases, and allows the effects of chemical weathering to be more effective as a result.- Erosion: The transportation of regolith, caused by flowing water, gravity, wind, or ice.Transported regolith is called sediment.There are three principal families of sediment:- Clastic: Bits of broken rock and minerals that are moved as solid particles. Examples include gravel, sand, silt and clay.- Chemical: Dissolved substances are transported in solution and precipitated. Examples include salt, calcite, and gypsum- Biogenic: From organisms. Examples include calcium carbonate shells, and peat in