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AnOutlineofGEOLOGYSchoolofGeosciencesandTechnology2013/5/10版权所有：wangke部分图片来源于网络CONTENTSCHAPTER1IntroductiontoGeologyCHAPTER2TheEarthCHAPTER3TheCrustCHAPTER4MagmatismandIgneousRocksCHAPTER5ExogenicProcessesandSedimentaryCHAPTER6MetamorphismandMetamorphicRocksCHAPTER7StructureandTectonicCHAPTER8HistoricalGeologyCHAPTER9PaleontologyCHAPTER10BasinsCHAPTER1IntroductiontoGeologyWhatisGeology?GeologyisthestudyoftheplanetEarth.Itisconcernedwiththeoriginoftheplanet,thematerialandmorphologyoftheEarth,anditshistoryandtheprocessacted/actingonit.Theword“geology”wasfirstusedbyaSwissscholar-H.B.DeSaussure(1740-1799)in1779.Theprefix“geo-”means“Earthorland”,whilethesuffix“-logy”means“subject-asourceorareaofstudy”.TolearnGeology,youneedstudythesefirst:MathematicsPhysicsChemistryBiologyRockmechanicsFluidmechanicsCHAPTER2TheEarth2.1TheshapeandsizeoftheEarthWepictureEarthasaballwiththeNorthPoleatthetopandtheSouthPoleatthebottom.Longradius:6378.140kmShortradius:6356.779kmAverageradius:6371.012kmCircumferencearoundtheequator:40,075.16kmCircumferencearoundthepoles:40,008.00km2.2OuterlayeroftheEarthAtmosphere:includingallkindsofgas,suchasNitrogen,Oxygen,Argon,CarbonDioxideandWaterVapor.Hydrosphere:consistsofconsecutivewaterbody,Oceans,Rivers,GlaciersandUndergroundwater.Biosphere:thelayerwhichhaslivesonit.2.3InnerlayeroftheEarthCHAPTER3TheCrust3.1TheelementsintheCrustandtheirClarkeTillnowweknowthatthereare92naturalelementsinthecrustoftheEarth.AnAmericanscientist,F.W.Clarke,calculatedtheaveragepercentagesofallelementsfrom5,159rocksamplesofthecrust.Oxygen:48.60%Silicon:26.30%Aluminum:7.73%Ferrum:4.75%Calcium:3.45%Sodium:2.74%Magnesium:2.06%Hydrogen:0.76%Others:1.20%3.2MineralsAmineralisanynaturallyformed,solidchemicalsubstancehavingarelativelydefinitechemicalcompositionandacharacteristiccrystalstructure.SOMECOMMONMINERALSGold(Au)Silver(Ag)Copper(Cu)Sulfur(S)Diamond(C)Fluorite(CaF2)萤石Halite(NaCl)石盐Quartz(SiO2)Calcite(CaCO3)Dolomite(CaMg[CO3]2)Malachite(Cu2[CO3](OH)2)Olivine((Fe,Mg)2SiO4)CHAPTER4MagmatismandIgneousRocksRockisanynaturallyformed,consolidatedorunconsolidatedmaterial(excludingsoil)composedofoneormorerock-formingminerals.Inotherwords,allrocksarecomposedofminerals.Accordingtotheorigin,rockscanbeclassifiedintothreetypes-igneousrocks,sedimentaryrocksandmetamorphicrocks,andtheirpercentageinthecrustareasfollowing:Igneousrocks:66%ofvolumeofthecrustSedimentaryrocks:8%ofvolumeofthecrustMetamorphicrocks:20%ofvolumeofthecrustTheEarthisabout4600Maold,andtheoldestrocksthatcanbefoundtodayisthe“GreenRock”inthenorthofCanada.Theserocksareabout4280Maold,whichcomefromaerolitesandcometsthatfelldownfromthespacewhilethecrustbegantorefrigerate.Ma:1millionanniversary4.1MagmatismIgneousrocksareformedbythecoolingandconsolidationofmagma.Magmaisnaturallyoccurringmobilematerialwithhightemperature,generatedwithintheEarthandcapableofintrusionandextrusion.Hightemperature:650℃to1,400℃ComplexcomponentsViscousandMobile4.2VolcanoAvolcanoisaventinthesurfaceoftheEarththroughwhichmagmaandassociatedgasesandasherupt.Typicalcomponentsofavolcanoinclude:Volcaniccone火山锥Crater/Caldera火山口/破火山口Vent火山通道Magmachamber岩浆房4.3SpecialstructureColumnarjointing(柱状节理)isakindofstructureoftenformedinbasaltic(玄武岩的)flowsasaresultofcontractionduringcoolingoflava.4.4MajorigneousrocksPeridotite橄榄岩Kimberlite金伯利岩Granite花岗岩Basalt玄武岩CHAPTER5ExogenicProcessesandSedimentary5.1TypesofexternalprocessesWeatheringisthechemicalalternationandmechanicalbreakdownofrockmaterialsduringexposuretoair,moistureandorganicmatter.Therearemechanicalweatheringandchemicalweathering.Erosionisthecomplexgroupofrelatedprocessesbywhichrockisbrokendownphysicallyandchemically,andtheproductsmoved.Weatheringanderosionarecloselyrelatedtoeachotherandcannotbedividedclearly.Transportationisaphaseofsedimentationconcernedwiththeactualmovement,shifting,orcarryingawaybynaturalagents(flowingwater,ice,wind,orgravity)ofsedimentsorofanyweatheredmaterials.Sedimentationistheprocessofdepositingandaccumulatingsedimentsinlayersinsuitablesiteswheretheagentsgiveuptransportingthesediments.Diagenesisistheprocessthroughwhichtheloosesedimentsarecompactedandcementedintosedimentaryrocks.5.2ThecompositionofsedimentaryrocksParentrock(sourcerock,母岩)istherockfromwhichfragmentsandotherdetachedpieceshavebeenderivedtoformalatersedimentaryrock.Sourcearea(provenance,物源区)isaplaceoforiginfromwhichtheconstituentmaterialsofasedimentaryrockorfaciesarederived.Concerningthecompositionofsedimentaryrocks,weoftenrefertochemicalandmineralcompositions.a.Chemicalcomposition.Afterlong-termexternalprocessesdifferentsedimentaryrockshavedifferentchemicalcompositions,suchas:Sandstone:SiO2Shale:SiO2,Al2O3Limestone:CaCO3Fe2O3FeO(FeOFe2O3inigneousrocks),reason:4Fe3O4+O2=6Fe2O3K2ONa2O(Na2OK2Oinigneousrocks),becausecationNa+canbeeasilydissolvesintheseawaterandcationK+remainsinthesoils.TherearemoreH2O,CO2andorganicmatterinsediments.b.Mineralcompositions.Thecommonmineralsinsedimentaryrocksaremicaandclays,quartzandfeldspars,aswellascarbonate(CaCO3,CaMg(CO3)2),etc.mica(KAl2[AlSi