Earth ResourcesGeology—study of dynamic processes in the earth’s surface & interiorSlow processes, with occasional rapid eventsGeologic timeBillions of yearsChange is rule, not exceptionEarthGolf ball-ish, peanut M & MCore, mantle, crustEarthCoreInnermost zoneIntensely hotSolid inner partSurrounded by liquid core—molten or semi-solid materialMantleThickOutermost—solid rockUnderneath—hot, semisolid rock, flows slowly: asthenosphereAsthenosphere—plastic: can be deformedCrustOutermostThinnestContinental crust—29% of earth’s surfaceOceanic crust—71% of earth’s surfaceGeologic ProcessesChanges on crust reflect internal processesInterior processes—changes in interiorHeat, gravityCore cooling—heat released as inner core coolsOuter core—cools and solidifiesGeologic ProcessesAsthenosphereConvection cells—move heat and rock in conveyor belt motion—hot rock rises, cool rock downwardMantle plumes—mantle rock moves upward in vertical column, fans outPlate TectonicsTectonic plates—solid, rigid plates: 15Continental and oceanic crusts and outermost portion of mantle—lithosphereMove slowly, on asthenosphereRange from 1 cm -> 18 cmMove apart and slam into each otherCreate mountains, ridges and trenchesPlate TectonicsVideo clipPlate BoundariesDivergent—plates move awayConvergent—plates pushed togetherOceanic plate runs into continental—continental over oceanicSubduction—distinct subduction zonesTransform Fault—plates slide past each otherWhy Study ThisExplains distribution of plant and animal lifeProvides insight into distribution and location of valuable materialsMay explain mass extinctions—ocean movements, heat redistributionMinerals and RocksMinerals—elements or inorganic compounds, natural, regular internal crystalline structureRock—combination of one or more minerals, most have more than mineralRock types—igneous, sedimentary, metamorphicIgneous RockFormed below or on surfaceMagma rises up from mantle, cools, hardensGranite—belowLava—aboveBulk of crustCovered with soil, sedimentary rocksSource of non-fuel mineral resourcesWeatheringExposure to air, water, temperature change, reactive chemicalsRock breaks downMechanical—no chemical changeChemical—selective removal of components weakens rocksSmall pieces transported by air, water gravitySedimentary RockFormed from sedimentWeathered rockWater, wind, gravity, iceDeposited in layers, accumulatePressure & dissolved minerals bind sedimentSandstone, shale, dolomite, limestone, lignite, bituminous coalMetamorphic RockPreexisting rock is subjected to high temperatures, high pressures, chemically active fluids, or combinationChange structure, physical properties, appearanceAnthracite, slate, marbleRock CycleCycling of rock typesMillions of yearsConcentrates non-renewable resourcesSo What?We use rocks and minerals—resourcesMetals—lightness, strength, malleability: tools and machinesNon-metals—salt, clay, sand, phosphatesEnergy—coal, oil, natural gas, uraniumResourcesNonrenewable—take long time to produceMore than 100 nonrenewable resourcesOre—rock containing enough resource to make mining profitableUSGS NonrenewableIdentified resource—known location, quantity & quality, or existence based on known evidenceReserves—identified resources usable resource extracted profitably at today’s pricesUSGS (cont’d)Undiscovered—potential supplies assumed to exist on basis of geologic knowledge and theory, unknown specific location, quantity, qualityOther—undiscovered resources and discovered resources that are not reservesResource IdentificationAerial and satellite photosRadiation sensingMagnetometerGravimeterSeismicChemical analysisExtractionShallow depositsSurface miningRemove overburdenWaste soil and rocks—spoilsExtractionTopography and resource determine methodOpen-pitDredgingArea stripContour stripMountain top removalPlacerReclaimed minesExpensivePartially successfulExtractionSubsurface mining—deep depositsVertical shafts, horizontal tunnelsLess spoilsLeaves more resource behindMore expensiveMore dangerousProcessingRemove metals by heat or chemical treatmentHeat—smeltingAir & water pollution--sulfurChemical—heap-leachPiles of crushed rock sprayed with cyanideRecyclingCheaper than mining for some mineralsMinimills—recycle iron and steelSubstitution—new materialsEnvironmental Impacts of Nonrenewable Mineral ResourcesSupplies of Mineral ResourcesGeological HazardsEarthquakesTsunamisVolcanoesMass wastingLandslidesSlumpsmudslidesEarth ResourcesEarth ResourcesGeologyGeology——study of dynamic processes in the study of dynamic processes in the earthearth’’s surface & interiors surface & interiorSlow processes, with occasional rapid eventsSlow processes, with occasional rapid eventsGeologic timeGeologic timeBillions of yearsBillions of yearsChange is rule, not exceptionChange is rule, not exceptionEarth Earth Golf ball-ish, peanut M & MGolf ball-ish, peanut M & MCore, mantle, crustCore, mantle, crustEarthEarthCore Core Innermost zoneInnermost zoneIntensely hotIntensely hotSolid inner partSolid inner partSurrounded by liquid coreSurrounded by liquid core——molten or semi-solid molten or semi-solid materialmaterialMantle Mantle ThickThickOutermostOutermost——solid rocksolid rockUnderneathUnderneath——hot, semisolid rock, flows slowly: hot, semisolid rock, flows slowly: asthenosphereasthenosphereAsthenosphereAsthenosphere——plastic: can be deformedplastic: can be deformedCrust Crust OutermostOutermostThinnestThinnestContinental crustContinental crust——29% of earth29% of earth’’s surfaces surfaceOceanic crustOceanic crust——71% of earth71% of earth’’s surfaces surfaceGeologic ProcessesGeologic ProcessesChanges on crust reflect internal processesChanges on crust reflect internal processesInterior processesInterior processes——changes in interior changes in interior Heat, gravityHeat, gravityCore coolingCore cooling——heat released as inner core coolsheat released as inner core coolsOuter coreOuter core——cools and solidifiescools and solidifiesGeologic ProcessesGeologic ProcessesAsthenosphereAsthenosphereConvection cellsConvection cells——move heat and rock in conveyor belt move heat and rock in conveyor belt motionmotion——hot rock rises, cool rock downwardhot rock rises,
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