Presentation on theme: "Earth System and Recourse. Earth’s Layers The Earth’s crust is made up of a series of rigid plates, called tectonic plates, which move in response to."— Presentation transcript:
Earth’s Layers The Earth’s crust is made up of a series of rigid plates, called tectonic plates, which move in response to forces in the mantle.
There are three major concentric zones, layers: Core, Mantle, and Crust Asthenosphere: very hot, party melted rock. Part of the mantle. Roughly 180km thick (112 miles) Continental Crust: below the continent, mainly consist of igneous rocks about 5-10 km thick (15-56 miles) Oceanic crust: below the oceans. Thinner than the continental crust. About 5-10 km thick ( 3.6-6.2 miles) Lithosphere: outer shell of the earth, composed of crust and rigid Mohorovicic discontinuity: the border between crust and mantle AKA MOHO
To Learn more about the rock cycle visit this website: http://www.learner.org/interactives/rockcycle/diagram.html http://www.learner.org/interactives/rockcycle/diagram.html
Divergent Plate- where the plates move apart in opposite directions Convergent Plate Boundary- The plates are pushed together by internal forces Transform Fault- where plates slide and grind past one another along a fracture (fault) in the lithosphere. Animations: Divergent, Convergent, and Transform http://www.wwnorton.com/college/geo/animations/basic_plate_boundaries.htm Transform: http://www.wwnorton.com/college/geo/animations/transform_faulting.h tm http://www.wwnorton.com/college/geo/animations/transform_faulting.h tm
Nonrenewable resource: a concentration of naturally occurring material in or on the earth’s crust that can be extracted and processed into useful material at an affordable cost. Metallic resources: iron, copper, and aluminum Nonmetallic resources: salt, clay, sand, phosphates, and soil Energy resources: coal, oil, natural gas, and uranium Ore: rock containing enough of one or more metallic minerals to be mined profitably.
Overburden: soil and rock and usually discards it as waste material called spoils. Types of surface mining: open-pit mining, dredging, area strip mining, contour strip mining, and mountaintop removal Surface Mining Control Act: (1977) requires mining companies to restore most surface- mined land so it can be used for the same purpose as before it was mined
Removes coal and various metal ores that are too deep to be extracted by surface mining. Disturbs less than one- tenth as much land as surface mining and produce less waste material. Hazards: include cave-ins, explosions, and lung diseases (such as black lung) caused by prolonged inhalation of mining dust.
Environmental Effects of Mining Steps Mining exploration, extraction Processing transportation, purification, manufacturing Use transportation or transmission to individual user, eventual use, and discarding Environmental Effects Disturbed land; mining accidents; health hazards; mine waste dumping; oil spills and blowouts; noise; ugliness; heat Solid wastes; radioactive material; air, water, and soil pollution; noise; safety and health hazards; ugliness; heat Noise; ugliness; thermal water pollution; pollution of air, water, and soil; solid and radioactive wastes; safety and health hazards; heat
Mine, use, throw away; no new discoveries; rising prices A Recycle; increase reserves by improved mining technology, higher prices, and new discoveries Recycle, reuse, reduce consumption; increase reserves by improved mining technology, higher prices, and new discoveries Depletion Times The amount of time it will take to use up a certain proportion of a mineral. (Typically 80%) B C Production Present Depletion time A Time Depletion time B Depletion time C