GEO01 First Quarter (1) PDF

CO1: Earth and its Neighbors Geology - scientific study of Earth. Physical Geology - study of Earth’s materials, surface and interior change, and the forces that cause the change. An Average American uses: Nonmetals - ~8.666kg/person/year Metals - ~147/kg/person/year Energy - 9...

CO1: Earth and its Neighbors Geology - scientific study of Earth. Physical Geology - study of Earth’s materials, surface and interior change, and the forces that cause the change. An Average American uses: Nonmetals - ~8.666kg/person/year Metals - ~147/kg/person/year Energy - 958 gallons petroleum; 1908 kg coal, 2,775m3 natural gas; 0.06 kg Uranium Earth as a System Closed System - a self-contained system in which the boundary permits the exchange of energy, but not matter, with the surroundings. Open System - Energy and matter flow in and out of the system. Earth Systems Atmosphere - gases that envelop the earth. - Gas that envelops Earth and one of the reasons it can support life. - Relatively shallow compared to Earth’s Geosphere and composed of mostly Nitrogen. 1. Troposphere - lowest layer where all weather occurs. Has a warmer base than the uppermost apportion as the base absorbs the heat by the Earth’s surface. 2. Stratosphere - layer where planes travel. Site of ozone layer that absorbs the UV rays from the sun. Temperature remains constant to a height of about 20 km with a gradual increase until 50 km above the surface. 3. Mesosphere - Temperature decreases with height until mesopause with a temperature approaching -90C above 80 km. 4. Thermosphere - Temperature increases by the absorption of very short-wave, high-energy solar radiation by Nitrogen and Oxygen atoms. The layer where the ISS orbits between 330 km and 435 km. Hydrosphere - water on or near the surface. Dynamic mass of water that continuously moves. - Ocean covers 71% of the Earth’s surface and 97.5% of its salt water and 2.5% freshwater surface (available from glaciers, groundwater, rivers and lakes). Ocean Geography Northern Hemisphere - known as the land hemisphere (61% land, 39% water) Southern Hemisphere - known as the water hemisphere (81% water, 19% land) Pacific Ocean - Largest and deepest ocean with the largest single geographic feature. Extends from the Arctic Ocean to the Antarctic Ocean. Indian Ocean - Third largest ocean. Largely a Southern Hemisphere water body bounded by Asia, Africa, Australia, and Antarctica. Atlantic Ocean - Second largest ocean bounded by almost parallel continental margins of Europe, Africa, and Americas. Arctic Ocean - Smallest and Shallowest ocean only being 7% the size of the Pacific Ocean. Also known as the Arctic Mediterranean Sea. Antarctic Ocean - known as the South Ocean and is defined by the Antarctic Convergence. Portions the Pacific, Atlantic, and Indian Ocean and lies about 50 degrees south latitude. - Antarctic Convergence - meeting of currents near Antarctica. Biosphere - all living/ once-living materials. - Earth is the only known place to hold life so far. - Covers all ecosystems from the soil to the rainforest, mangroves to coral reefs, plankton-rich ocean surface to the deep ocean. Geosphere - solid rocky Earth. - Earth’s formation is differentiated into the Crust, Mantle, Core. - Planetary Differentiation - process that created the Earth’s layered structure. Denser material sinks to the center while less dense floats to the top. Layering by Physical Properties - classification based on compositional density Lithosphere - (crust) the uppermost mantle. Relatively rigid and known to break due to stress and the site of most earthquakes. Breaks into large fragments called lithospheric plates. Asthenosphere - (Weak Sphere) ~100 km below the lithosphere until a depth of 660km. Where Convection is thought to occur. Mesosphere - lower mantle portion between 660 km to 2900 km depth. The Mantle gradually strengthens with depth due to the increase in pressure. Outer Core - liquid layer extending from 2900 km to 5150 km where S waves cannot travel through it. Circulates via convection which generates Earth’s Magnetic Field. Lehmann Discontinuity - the boundary between the inner and outer core discovered by Inge Lehmann. Inner Core - Solid inner core from 5150 to the Earth’s center. The Core is made out of solid iron and does not melt due to the immense pressure that exists in the center of the Earth. Layering by Chemical Properties - based on whether the layer is solid or liquid and could be on how weak or strong it is (Crust, Mantle Core). Crust - thinnest layer (5km - 80km); occupies 4500 minerals identified. - >90% of Earth’s crust is composed of minerals from only 5 groups (feldspars, pyroxenes, amphiboles, micas, and quartz). Mineral Identification - Requires determining the characteristic and physical properties and matching them with a mineral identification key. Color - mineral’s visible hue. Streak - color left when mineral is scraped. Luster - way light reflects off the surface. Hardness - scratch-resistance. External Crystal form - external geometric form. Cleavage - breakage along flat planes due to weaker bonds. Fracture - irregular breakage along strong bonds. Specific Gravity - density relative to water. Special Properties Striations - straight parallel lines on the flat surface of crystal faces. Magnetism - attracts to magnets Double Refraction - two images are visible when looking at the mineral. Chemical Tests - calcite effervesces in dilute HCL. The Many Conditions of Mineral Formation Precipitates - minerals formed from crystallizing liquid such as silicates and carbonates. Biological Activity - minerals formed from living organisms. Sublimation - minerals formed as gasses from volcanic vents crystallize into solid such as sulfur. Metallic Resources Metal Ores - metallic materials that can be profitably mined. Crystal Settling - early forming minerals settle to the bottom of a cooling magma body. Hydrothermal Fluids - most important source of metallic ore deposits. Contact metamorphic deposits. Hydrothermal veins - narrow ore bodies along joints and faults. Disseminated deposits. Hot-spring deposits. Nonmetallic Resources Not mined to extract a metal or an energy source. Construction materials - sand, gravel, limestone, and gypsum. Fertilizers and Evaporites - phosphate, nitrate, and potassium compounds; rock salt, gypsum, sulfur, asbestos. Other Nonmetallic: - Gemstones - diamonds, rubies, emeralds. - Asbestos, glass sand, fluorite, diatomite, graphite. Ores Formed by surface processes. Chemical Precipitation in Layers - Banded Iron, Manganese and Copper Ores. Placer Deposits - concentration of mineral deposits by stream processes. - Gold, platinum, diamonds, and other gemstones. Concentration by Weathering - Aluminum Ore - Bauxite. IGNEOUS ORE-FORMING ENVIRONMENTS Magmatic Concentration Deposit - Formed when magma cools; Sulfide minerals would crystallize early and sink to the bottom of the magma chamber (Gravity settling) and accumulate. Hydrothermal Deposit - Involves circulation of hot-water solutions through magma or through rock surrounding an igneous intrusion. Volcanogenic Massive Sulfide Deposit - Deposits of copper-zinc-lead concentrated on the ocean floor at divergent and convergent boundaries. - Formed by black and white smokers which are ocean ridge events that release hydrothermal fluids. Porphyry Deposit - Principal source of copper; When silica-rich magma intrudes and fractures the host rock. SEDIMENTARY ORE-FORMING ENVIRONMENTS Banded Iron Deposit - Largest and most important iron deposits; Consists of alternating iron-rich and silica-rich layers; >100 km sq. in area. MVT (Mississippi-Valley Type) Ore - Rain would percolate downward to the bottom of the basin where temperatures are high enough to dissolve metals. Secondary-Enrichment Deposit - When surface waters could oxidize ore minerals and yield acidic solvents that dissolve other minerals due to weathering. Residual Mineral Deposit - When rainwater leeches elements but leaves behind others as part of the process of forming soil. Placer Deposit - develops when rocks containing native metals erode. METAMORPHIC ORE-FORMING ENVIRONMENTS Skarn - Contact metasomatic deposits. Formed due to hydrothermal fluids released from magma which would alter the country rock to form complex assemblage of minerals. Exoskarn - deblops in any sedimentary country rock. Endoskarn - develops in igneous country rock. Ore - Aggregation of ore minerals and gangue metals may be extracted for profit. Gangue - Usually worthless, nonmetallic minerals of a deposit. MINING AND METALLURGY Mining - can be done at Earth’s surface or underground metals mined include iron, copper, aluminum, lead, zinc, silver, gold, and many others. - Strip mining - Open-pit mining - Placer Mining - Panning, Sluice boxes, hydraulic - Underground / bedrock mining. Negative environmental effects of mining - Tailings piles, surface scars, land subsidence, and acid mine drainage. Metallurgy - The science and technology of extracting metals from their natural sources and preparing them for practical use. Resources, The Environment, and Sustainability - Demand for resources is likely to increase as the world population grows. - Extraction and transportation of resources has an enormous environmental impact. - Leaving enormous holes in the ground. - Removing whole mountain tops - Massive oil spills - Greenhouse gas release ENVIRONMENT AND WASTE MANAGEMENT Waste - movable object with no direct use that is discarded permanently. Waste classification based on Waste classification based on component generator Solid Municipal Liquid Commercial Gas Industrial or Agricultural Wastes Types and How They Are Generated Municipal or Domestic Waste - Commercial Waste - Wastes produced ordinary day-to-day consumption of from business or trade. goods and services in a household. Medical Waste - resulting from Industrial Waste - Wastes resulting treatment of illnesses and trauma. from the manufacture of goods. Agricultural Waste - results from Mining Waste - results from mining agricultural processes. and ore processing; extraction and coal production Oil and Gas Waste - results from Nuclear Waste - by-products of discovery, extraction, and processing nuclear power plants and/or other of oil and natural gas radioactive activities Health and Environmental Impacts of Wastes  - Improper waste disposal from households and the community may pose serious health hazards and lead to spread of infectious diseases. Organic Domestic Waste - creates favorable conditions for pathogen/microbial growth wastes ferment; can result in various types of infectious and chronic diseases. Hazardous Waste Exposure - direct exposure can lead to diseases through chemical exposure. Agricultural and Industrial Wastes - can expose people to chemical and radioactive hazards. Hospital and Other Medical Waste - requires special attention since this can create major health hazards. Waste Treatment and Disposal Sites - must be located at a safe distance away from human settlement. Waste Management Disposal of solid and liquid wastes generally falls into 3 categories: 1. Isolation - encapsulating, burying or in some other way removing waste from the environment. 2. Incineration - burning of trash leaves behind a small volume residue to be isolated/attenuated. 3. Attenuation - dilutes or spreads trash/ pollutant so thinly so as to have little impact. Principle dilution as waste control. Special Situations on Waste Management Sewage Sludge - semisolid by-product of sewage treatment. Could be used as fertilizers. However, sludge from industries must be properly disposed of as it can contain heavy metals and other toxic substances. Landfill Gas Generation - Leakage may cause unexpected explosions; Can be utilized as fuel if extracted and purified properly. Leachate Pollution - may contaminate groundwater if not properly managed. Recycling - Resource Recovery - removal of certain materials from the waste stream for the purpose of recycling or posting them. Composting - use of microorganisms to decompose organic waste. Multiple Land-Use Strategies Nuclear Waste Disposal - must be isolated because they emit high-energy radiation that kills cells, cause genetic mutations and cancers, and death to individuals exposed to high doses. Storage for nuclear wastes must meet the following conditions: - Safe isolation for at least 250,000 years and Fail-safe handling and transport mechanism. - Safe from terrorism and natural disasters. - Geologically stable and Non-contamination of nearby natural resources.