工程地质课件

Introduction

绪论

1thedefinitionofcivilengineeringgeology

土木工程地质的基本概念

2Thepositionofengineeringgeologyinthecivilengineeringcoursesystem(

工程地质在土木学科体系中的位置)3themainsubstanceaboutengineeringgeology(工程地质学研究的具体内容)

4theimportanceofGE(学习意义)5Demands(requirements)（要求）Themaintopicsinintroduction

绪论中的主要内容thedefinitionofengineeringgeology

（工程地质学的基本概念）

(1)Engineeringgeologyisaboutapplyingallbranchesofthegeosciences(地质学)toassurethesafety,efficiency,andeconomyofengineeringandenvironmentalprojects.

（2）EngineeringGeologyisdevotedtotheinvestigation（勘察）,studyandsolutionoftheengineeringandenvironmentalproblemswhichmayariseastheresultoftheinteractionbetweengeologyandtheworksandactivitiesofmanaswellastothepredictionandthedevelopmentofmeasuresforpreventionormediationofgeologicalhazards（地质灾害）(3)Whicharemainlyconcernedwiththegeologicalproblemsencounteredincivilengineering.Itsmaintasksistoinvestigateandevaluatethegeologicalengineeringproblems,providethebasicinformationfortheplan,designandconstructionofthecivilengineering.2Thepositionofengineeringgeologyinthecivilengineeringcoursesystem(

工程地质在土木学科体系中的位置Corecourse（基础课程）

→

Differentialandintegral→algebra→probabilityandstatistics

→

engineeringmath→Physics→ChemicalTechnologicalcorecourse（专业基础课程）

→

Surveying→engineeringmapping→materials→surveying

→

engineering（工程测量）

→engineeringgeology(工程地质)→soil(rock)mechanics（岩土力学）

→

theoreticalmechanics→materialmechanics→structuremechanics→elasticorplastic（弹塑性）

→hydrolicmechanics（水力学）Specializedcourse（专业课程）

→concretestructure（砌体结构

→steelstructure（钢结构）

→roadengineering（道路工程）

→thedesignofroadsurvey（道路勘测设计）→bridgeengineering(桥梁工程)→trafficengineering(交通工程)→foundationengineering(基础工程)→constructiontechnology(building…)施工技术→engineeringmanagementandbudgetestimation→engineeringbiddingrehabilitation(building、brigde、road…)（工程招投标）3themainsubstanceaboutengineeringgeology(工程地质学研究的具体内容)ThepurposeofstudyingGEistoprovidegoodgeologicalenvironmentforengineeringortoevaluateandforecasttheengineeringgeologicalproblemsthatmayoccurredintheperiodoftheservicetime（服务期）ofthebuilding.onthisbase,togivetheeffectiveengineeringpreventionmethods.◆thestudyabouttopographyandlandforms

（地形地貌）◆thestudyaboutthefundamentalengineering

properties(physicalandmechanics)ofsoilsandrock(岩土工程性质）◆geologicalstructure（地质构造）

GeologicalEnvironment(GeologicalCondition)

地质环境和地质条件的含义4theimportanceofGE(学习意义)◆hydrogeology(水文地质：地下水条件)◆theanalysesofengineeringgeologicalproblems

（工程地质问题分析）

◆theengineeringinvestigation（工程勘察）5Demands(requirements)（要求）1tomasterthebasicconceptaboutEG2tocomprehendthemaingeologicalproblemsoccurredinengineering.knowingthathowtheproblemshappened,howcanwepreventit.3classdiscipline4finishthehomeworkontimeChapter1Thebasicinformationofearth

第一章地球的基本知识SECTION1-1Innerstructureofearth

第一节地球的内部结构

ThisregionisthincomparedtotheotherlayersintheEarth.

Itvariesinthicknessfrom10kmdeepto65kmdeep.

Thecrustismadeupoflighterrocksthat"float"ontopofthemantle.

This

layerincludesthecontinentsaswellastherockundertheoceans.

wehavebuiltmanydeepminesbutNONEhaveyetreachedthemantle!TheCrust(地壳)软流圈岩石圈上地慢有关岩石圈(lithosphere)StructureoftheEarth‘scrustandtopmostlayeroftheuppermantle（上地慢）.Thelithosphere（岩石圈）consistsoftheoceaniccrust,continentalcrust,anduppermostmantle.Beneaththelithosphereistheasthenosphere（软流圈）.Thislayer,whichisalsopartoftheuppermantle,extendstoadepthofabout200kilometers.Sedimentarydepositsarecommonlyfoundattheboundariesbetweenthecontinentalandoceaniccrust.Thisregionliesunderthecrustandisapproximately2900kmthick.

Themantleismuchdenserthanthecrust(whichiswhythecrustfloatsontop)andhasatexturemuchliketar.

Therockinthisregionisrichincompoundsmadefromiron,magnesium,andsiliconwhichaccountsforwhyitisdenserthanthecrust.TheMantle（地幔）Thisregionisdividedintotwoparts.

TheouterpartiscalledtheOuterCore.

Itisabout2100kmthickandmadeofliquidnickelandiron.

TheinnerpartiscalledtheInnerCoreanditistherealcentreoftheEarth.

Thispartisabout2800kmindiameterandismadeofsolidironandnickel.TheCore:SECTION1-2PlateStructureTheory

第二节板块构造理论1PacificPlate(太平洋板块)

2NorthAmericanPlate（北美板块）

3SouthAmericanPlate

（南美板块）4EurasianPlate（欧亚板块）

5AfricanPlate（非洲板块）

6IndoAustralianPlate（澳印板块）

7AntarcticPlate（南极州板块）

1PacificPlate2NorthAmericanPlate

3SouthAmericanPlate4EurasianPlate

5AfricanPlate6IndoAustralianPlate

7AntarcticPlate

板块构造理论板块的形成（大陆漂移）德国气象学家阿尔弗雷德·魏格纳（AlfredWegener）

海底扩张理论（TheoryofOceanFloorSpreading）海底扩张的证据（沉积物的年龄）海底扩张的结果（喜马拉雅山的形成）

海沟的形成岩石循环的概念SECTION1-3:TheconceptofGeologicalAction（function）第三节地质作用的概念1Whatisgeologicalaction（基本定义）

meantheactionsthatmakealterationforthecomposition，structure,shapeoftherockcyclebecauseofthenaturaldynamics.

CrustmovementSunnaturaldynamicsWindglaciergravitationwater2

TheclassificationoftheGeo.Action

（地质作用分类）

(1)

outer-dynamicsgeologicalaction(外动力地质作用)

dynamicsourceisfromthesun,gravity,attractionforcebetweensunandmoon.

▶Weathering（风化作用）

→theRockisdestroyedattheplacewhereitwasformedbecauseoftheouterdynamics.

▶Erosion（剥蚀作用）

→Rockbody岩体isseparatedfromitsmotherrock

（母岩）becauseofthewater,wind,glacier.

▶Carrying(搬运作用)→theprocessthatrockiscarriedfromoneplacetoantherplace.Becauseof…

▶

Sedimentation（沉积作用）

→theprocessinwhichthecarryingmaterialssinktothebottomofgroundwhenthepowerofgravityofthematerialsisbiggerthanthecarryingforce.

▶

Rock-formationaction（成岩作用）

→theprocessthatthematerialssunktogroundsurfacetobecomehardorsolidrockbody.

▶Crustmovement（地壳运动）

▶B:Magmatism(magmaticactivities)岩浆作用

(magmaticintrusionandvolcaniceruption)

▶Earthquake（地震作用）

(2)Inner-dynamicsgeologicalaction(内动力地质作用)(thedynamicssourceisfromearth▶Metamorphism（变质作用）

Becauseofthehighpressureandortemperature,therockischangedtoanewkindofrock,Thisrockiscalledmetamorphicrock..Everygeologicalphenomenaistheresultofgeologicalaction.Including:Amineral,rock,Landshape(mountain,river,plain..)TectonicsRock

岩石Sincemineralsarethebuildingblocksofrocks,itisimportantthatyoulearntoidentifythemostcommonvarieties.Mineralscanbedistinguishedusingvariousphysicaland/orchemicalcharacteristics,but,sincechemistrycannotbedeterminedreadilyinthefield,thephysicalpropertiesofmineralsareusedtoidentifythem.§2-1:Themainmineralsintherock(造岩矿物)♥

Crystalform（晶形）

♥

Hardness（硬度）

(relativetoasteelbladeoryoufingernail),

♥

colour(真色，假色，它色)

♥

Luster（光泽）

♥

Streak(条痕)

(thecolourwhenamineralisgroundtoapowder).

♥cleavage（解理）Physicalpropertiesofmineralsincludefeaturessuchas：Quartzishard-itcaneasilyscratchasteelknifeblade.Inmanyrocks,quartzgrainsareirregularinshapebecausecrystalfacesarerareandquartzdoesnothaveacleavage(ie,itdoesnotbreakonregularflatfaces).1Quartz(石英):Quartzisaglassylooking,transparentortranslucentmineralwhichvariesincolourfromwhiteandgreytosmoky.Whenthereareindividualcrystalstheyaregenerallyclear,whileinlargermassesquartzlooksmoremilkywhite.油脂光泽Feldsparisalsohardbutcanbescratchedbyquartz.Feldsparinigneousrocks（火成岩）formswelldevelopedcrystalswhichareroughlyrectangularinshape,andtheycleaveorbreakalongflatfaces.Thegrains,incontrasttoquartz,oftenhavestraightedgesandflatrectangularfaces,someofwhichmeetatrightangles.2Feldspar（长石）:Feldsparistheothercommon,light-colouredrock-formingmineral.Insteadofbeingglassylikequartz,itisgenerallydulltoopaque（不透明）withaporcelain-likeappearance.Colourvariesfromred,pink(orthoclase正长石),andwhitetogreen,grey(plagioclase斜长石).Plagioclase斜长石Orthoclase正长石Themostcommonamphiboleishornblende（角闪石）.Hornblendeisquitesimilartoaugite（普通辉石）inthatbotharedarkminerals,howeverhornblendecrystalsaregenerallylonger,thinnerandshinierthanaugiteandthemineralcross-sectionsarediamond-shaped.hornblende（角闪石）3Amphibole（闪石）Themostcommonpyroxenemineralisaugite.Augiteisgenerallydarkgreentoblackincolourandformsshort,stubby（短而粗）crystalswhich,ifyoulookatanend-onsection,havesquareorrectangularcross-sections.Pyroxene（辉石）4Pyroxene辉石Talcoccursingranular（粒状的）orfoliated（片状的）massessometimesknownassoapstone（皂石）.Itiswhitetogreen,sometimesgreyorbrownish.Itisverysoftandwillbescratchedbyafingernail.Ithasagreasyfeel（滑感）5Talc（滑石）Olivineinthejewellerytrade,isyellow-green,translucent（半透明的）andglassylooking.Crystalsarenotcommon;itusuallyoccursasroundedgrainsinigneous（火成的）rocksorasgranularmasses.Olivineisalmostashardasquartz;itdoesnothaveawell-developedcleavage.6Olivine橄榄石Micaiseasilydistinguishedbyitscharacteristicofpeelingintomanythinflatsmoothsheetsorflakes（薄片）.Thisissimilartothecleavageinfeldsparexceptthatinthecaseofmicathecleavageplanesareinonlyonedirectionandnorightanglefacejoinsoccur.Micamaybewhiteandpearlyordarkandshiny.7Mica云母8Gypsum(plasterstone,石膏)9Kaolinite(高岭石)10Montmorillonite（蒙脱石）11Watermica（伊利石）§2-2:Rock(岩石)(一种或多种矿物组成的集合体)

一、Theclassificationofrockaccordingtothecauseofformationigneousrock（岩浆岩）

(magmarock)sedimentaryrock（沉积岩）

metamophicrock（变质岩）岩石二、Igneousrock1theformationofigneousrock:DeepwithintheEarth,rockiskeptinamolten（融熔的）stateduetoextremetemperatureandpressure.

Thismoltenrockiscalledmagma（岩浆）.

Themagmaisconstantlymovingandsometimesmovesitswaytothesurfacethroughthecracks（裂缝）inthesolidrock.

Onceitreachesthesurface,itiscalledlava（熔岩）.

Thelocationitpushesthroughtothesurfaceiscalledavolcano（火山）.

Theopeninginthevolcanothatthelavaeruptsoutofiscalledavent(出口).

Formanyvolcanos,thereismorethanonevent.

Oftenvolcanoshaveafunnel（漏斗）shapewithapitatthetop.

Thispitiscalledavolcaniccrater（火山口）.

Ifthiscraterbecomesverylarge,thewallsofthecratermightcollapsetoproduceafeaturecalledacaldera（喷火山口）HowIgneousrockrockIsFormedPyroclasticash(火山灰)Batholith岩基Captivemass俘虏体laccolith岩盘岩墙Rockwall岩株Volcanoneck火山颈Lavaflow岩流theformationstateofigneousrock（岩浆岩的产状）Sill岩床3theclasscificationofigneousrock（岩浆岩的分类）

（1）Accordingtotheformationstate(按产状)

◈IntrusiveIgneousRocks（侵入岩）

-usuallymediumtocoarsegrainedtextureduetoslowcooling.Typicallylightcoloured.

◈ExtrusiveIgneousRocks（喷出岩）

-glassyorfine-grainedduetorapidcooling.Mayhavevoidsduetodegassingofthemagma.Typicallydarkcoloured.(2)AccordingtotheSilicaContentandMineralComposition(根据二氧化硅含量)

◈AcidIgneousRocks(酸性岩)-silicarich(>65%byweight)composedmainlyoflightcolouredminerals(eg.feldspars,quartz)

◈IntermediateIgneousRocks（中性岩）

silica50-65%byweight,composedmainlyoffeldspars,somemafic（铁镁质的minerals,withsomequartz.

◈BasicIgneousRocks（基性岩）

-silicapoor(<50%byweight)containsignificantamountsofmaficordarkcolouredferromagnesianminerals(eg.olivines,pyroxenes,amphiboles,micas).Nofreequartz.thedescriptionofmainigneousrock

（岩浆岩描述）

◈granite（花岗岩）Graniteisanigneousrockthatiscomposedoffourminerals.Thesemineralsarequartz,feldspar,mica,andusuallyhornblende.Graniteformsasmagmacoolsfarundertheearth'ssurface.Becauseithardensdeepunderground，itcoolsveryslowly.Thisallowscrystalsofthefourmineralstogrowlargeenoughtobeeasilyseenbythenakedeye.Graniteisanexcellentmaterialforbuildingbridgesandbuildingsbecauseitcanwithstandthousandsofpoundsofpressure.Itisalsousedformonumentsbecauseitweathersslowly.Engravingsinthegranitecanbereadforhundredsofyears,makingtherockmorevaluable.GraniteisquarriedinmanyplacesintheworldincludingtheUnitedStates.TheStateofNewHampshirehasthenickname"GraniteState"becauseoftheamountofgraniteinthemountainsofthatbeautifulstate.TheCanadianShieldofNorthAmericacontainshugeoutcroppings(surfacerocks)ofgranite.

◈

porphyriticgranite(花岗斑岩)

shallowintrusiverock（浅成侵入岩）

moderatecrystallization（中等结晶）

porphyriticstructure斑状结构

quartz-feldspar-blackmica花岗斑岩

◈rhyolite

（流纹岩）

Rhyoliteisverycloselyrelatedtogranite.Thedifferenceisrhyolitehasmuchfinercrystals.Thesecrystalsaresosmallthattheycannotbeseenbythenakedeye.Rhyoliteisanextrusiveigneousrockhavingcooledmuchmorerapidlythangranite,givingitaglassyappearance.Themineralsthatmakeuprhyolitearequartz,feldspar,mica,andhornblende.Rhyolite流纹岩

◈Diorite(闪长岩)1abyssalintrusiverock2wellcrystallization3feldspar,quartz,amphibole◈

Dioriteporphyrite（闪长玢岩）1shallowintrusiverock,2mediancrystallization3feldspar,quartzamphiboleDaciteisanextrusiveigneousrock.Theprinciplemineralsthatmakeupdaciteareplagioclase,quartz,pyroxene,orhornblende.Dacite安山岩◈Dacite（安山岩）Andesite

◈pyroxenire(辉岩)

1abyssalintrusiverock2wellcrystallization3amphibole,phyroxenefeldspar

Basaltsaredarkcolored,fine-grainedextrusiverock.Themineralgrainsaresofinethattheyareimpossibletodistinguishwiththenakedeyeorevenamagnifyingglass（放大镜）.Theyarethemostwidespreadofalltheigneousrocks.Mostbasaltsarevolcanicinoriginandwereformedbytherapidcoolingandhardeningofthelavaflows.SomebasaltsareintrusivehavingcooledinsidetheEarth'sinterior.◈basalt玄武岩1ultrabasicrock（超基性岩石）

(sio2<45%)2abyssalintrusiverock（深成岩）

3wellcrystallization（结晶好）

4olivine；pgroxene◈olivinerock(橄榄岩)◈Obsidian黑耀岩Obsidianisaveryshinynaturalvolcanicglass.Whenobsidianbreaksitfractureswithadistinctconchoidal（贝壳状的）fracture.Noticeinthephototothelefthowitfractures.Obsidianisproducedwhenlavacoolsveryquickly.Thelavacoolssoquicklythatnocrystalscanform.Whenpeoplemakeglasstheymeltsilicarockslikesandandquartzthencoolitrapidlybyplacingitinwater.Obsidianisproducedinnatureinasimilarway.Obsidianisusuallyblackoraverydarkgreen,butitcanalsobefoundinanalmostclearform.Pumiceisaverylightcolored,frothy（起泡的）volcanicrock.Pumiceisformedfromlavathatisfullofgas.Thelavaisejectedandshotthroughtheairduringaneruption.Asthelavahurtles（急飞）throughtheairitcoolsandthegasesescapeleavingtherockfullofholes.◈Pumice（浮石）Pumiceissolightthatitactuallyfloatsonwater.Hugepumiceblockshavebeenseenfloatingontheoceanafterlargeeruptions.Somelavablocksarelargeenoughtocarrysmallanimals.三、sedimentaryrock（沉积岩）1theformationofsedimentaryrock:Forthousands,evenmillionsofyears,littlepiecesofourearthhavebeeneroded--brokendownandwornawaybywindandwater.Theselittlebitsofoureartharewasheddownstreamwheretheysettletothebottomoftherivers,lakes,andoceans.Layerafterlayeroferodedearthisdepositedontopofeach.Theselayersarepresseddownmoreandmorethroughtime,untilthebottomlayersslowlyturnintorock.HowSedimentaryRockIsFormedSedimentsaresubdividedintothreetypes:

▦1

Clasticordetritalsediments（碎屑岩）

Comprisingparticlesofvarioussizescarriedinsuspensionbywind,waterorice.Sand(砂岩)isanexampleofaclasticsediment.Silt（粉砂岩）andsandsizeparticlesarecarriedinsuspensionbywind,waterandice.

2theclassificationofsedimentaryrock:

▦2

Chemicalorprecipitatedsediments（化学岩）

whicharecarriedinaqueoussolution.Salt(halite)isanexampleofachemicalprecipitate.·

▦3

Organicorbiogenicsediments（有机岩）

precipitatedoraccumulatedbybiologicalagents.Manyorganismspromotetheprecipitationofcalcitetoformbiogenicallyprecipitatedcalcareous（含钙的）muds.3Thetextureandstructureofsedimentaryrock

沉积岩的结构和构造沉积岩的层理构造平行层理斜层理波状层理印模粒序层理交叉层理沉积岩的结构特征砂粒孔隙胶结物砂粒粘粒粉粒铁饼形的Sphericity球形度[sfe’risiti]4thedescriptionofsedimentaryrockConglomeraterocksaresedimentaryrocks.Theyaremadeupoflargesedimentslikesandandpebbles（鹅卵石）.Thesedimentissolargethatpressurealonecannotholdtherocktogether;itisalsocementedtogetherwithdissolvedminerals.◈

gravelstone(conglomerate)砾岩(clasticrock)◈

sandstone(d=2-0.05mm)砂岩Sandstonerocksaresedimentaryrocksmadefromsmallgrainsofthemineralsquartzandfeldspar.Theyoftenforminlayersasseeninthispicture.Theyareoftenusedasbuildingstones.◈

siltstone(d=0.05-0.005mm)粉砂岩◈

mudstone(d<0.005mm)泥岩kaolinite(高岭石)montorillonite（蒙脱石）

watermica（伊利石）MineralCompositionShalerockisatypeofsedimentaryrockformedfromclaythatiscompactedtogetherbypressure.Theyareusedtomakebricks◈

shalestone(d<0.005mm)页岩Limestonerocksaresedimentaryrocksthataremadefromthemineralcalcitewhichcamefromthebedsofevaporatedseasandlakesandfromseaanimalshells.Thisrockisusedinconcreteandisanexcellentbuildingstoneforhumidregions.colorgrey◈

limestone石灰岩◈

dolomiterock白云岩color:white-greymineral:dolomit◈

Gypsum石膏Gypsumrocksaresedimentaryrocksmadeupofsulfatemineralandformedastheresultofevaporatingseawaterinmassiveprehistoricbasins.ItisverysoftandisusedtomakePlasterofParis,casts,molds,andwallboards.四、Metamorphicrock（变质岩）Metamorphicrocksaregeneratedbyrecrystallizationofeitherigneousorsedimentaryrocksbytheactionofanyorallofthefollowing:Pressure,Temperature,PoreFluids.

Thetypeofmetamorphicrockisdeterminedbytheparentrock（母岩）andtheP/Tconditions.Ingeneral,metamorphismcauses:GrowthofnewmineralsDeformationandrotationofmineralgrainsRecrystallizationofmineralsaslargergrains1theformationandclassificationofMetamorphicrocks变质岩的形成接触变质岩的形成区域变质岩的形成2thedescriptionofMetamorphicrocks

◈

Marble

（大理岩）Marbleismetamorphosedlimestoneordolomite.Bothlimestoneanddolomitehavealargeconcentrationofcalciumcarbonate(CaCO3).Marblehasmanydifferentsizesofcrystals.

Marblehasmanycolorvariancesduetotheimpurities(杂质)presentatformation.Someofthedifferentcolorsofmarblearewhite,red,black,mottledandbanded,gray,pink,andgreen.Marbleismuchharderthanitsparentrock.Thisallowsittotakeapolishwhichmakesitagoodmaterialforuseasabuildingmaterial,makingsinktops,bathtubs,andacarvingstoneforartists.Today,headstonesaremadefrommarbleandgranitebecausebothoftheserocksweatherveryslowlyandcarvewellwithsharpedges.◈

Quartzite（石英岩）Quartziteiscomposedofsandstonethathasbeenmetamorphosed.Quartziteismuchharderthantheparentrock,sandstone.Itformsfromsandstonethathascomeintocontactwithdeeplyburiedmagmas.Quartzitelookssimilartoitsparentrock.Thebestwaytotellquartzitefromsandstoneistobreaktherocks.Sandstonewillshatterintomanyindividualgrainsofsandwhilequartzitewillbreakacrossthegrains.

Geological

Structure

地质构造§2-1geologicaltimeandChronologicalscale

地质年代与地质年代表

一、GeologicalTime

Geologicaltimeisamethodoforderingandmeasuringpastevents.Theorderingofeventsusesagroupofobservationalmethodsknownas:

1Absolutedatingmethods(绝对年代法)

2Relativedatingmethods（相对年代法）1AbsolutedatingmethodsAbsolutedatingmethodsarethosethatgenerateanageinyears.Therearetwoprincipalmethods:oneisthemethodwhichrelyoneventinthegeologicalrecordwithverystrongannualcyclicity(周期性),suchastreegrowthrings,coralgrowthcyclesvarves（纹层）

(annualclaysedimentlayers).AnotherMethodsismorecommonlyusednowdayswhichrelyonthedecayofnaturallyoccurringradiogenicisotopes:

Radiometricdatingisnotwithoutdifficultiesbutisbyfarthemostwidespreadmethodappliedtodetermineabsoluteagesbetween100and4500My.Uranium(铀),Thorium（钍）

andPotassium（钾）arebyfarthemostcommonradiogenicisotopesintheEarth'scrust.Radiocarbonisimportantindatingorganicremainsfromtherelativelyrecentpast.2relativedatingmethodsRelativedatingmethodsusegeologicalprinciplestoplaceeventsinchronologicalorder.whichinclude:

♣stratasuperpositionmethod（地层层序法）♣fossilsuccessionmethod（化石演变法）♣themethodofrocklayerscontactrelation

（岩层接触关系法）.

♣Theprincipleofsuperpositionstatesthatolderbedsarecoveredbyyoungerbeds.Inotherword,theyoungestunitisusuallyatthetopinasedimentarysequence.TheyoungestlayerTheoldestlayer

♣Theprincipleoffossilsuccessionstatesthatorganismsevolvethroughtimesothatparticularformscanbeusedasagemarkerswherevertheyarefound.

♣

Themethodofrocklayerscontactrelationstatesthatthecontactrelationsamongrocklayersisthehistoryrecordsofcrustmovement,magmaactivities.Sogeologicaleventscanbeorderedbytherelationofrocklayers,theseincludes：①therelationsamongsedimentaryrock,

（沉积岩之间的接触关系）②therelationsamongtheigneousrock,（岩浆岩之间的接触关系）③therelationbetweensedimentaryrockandigneousrock.（沉积岩和岩浆岩之间的接触关系）①TherelationsamongsedimentaryrockTherelationsamongsedimentaryrockcanbedividedinto：

conformity（整合）

Unconformity（不整合）.Theconformitymeansthatstratawasformedinastablesedimentaryenvironment,thedipandstrikeofstrataarebasicallythesame.conformity（整合接触关系）Unconformity（不整合）.Theunconformitymeanthereisabreakinsedimentation,aperiodoferosionoranepisodeofdeformation,Unconformitiesrangefromminorerosionalbreakstostrongangulardiscordancesinbedding.Anunconformityindicatesaperiodwherenorockrecordisaccumulated.Theyaretime-breaksofindeterminatelength.整合接触平行不整合接触角度不整合接触②therelationsamongtheigneousrock,岩浆岩之间的接触关系Cross-cuttingrelationshipsamongigneousrocksindicatethatintrusionrocksmustbeyoungerthantherockstheycut.③therelationbetweensedimentaryrockandigneousrock.Cross-cuttingrelationshipsbetweenigneousrocksandsedimentaryrockIndicatethatsedimentaryrockincludedpebblesandfragmentsmustbeolderthanthehostrockcontainingthem.二、ChronologicalscaleThegeologictimescalewasoriginallyasetofrelativedatesbutthevariouseons（宙）,eras（代）,periods（纪）andepochs（世）havenowbeenaccuratelydatedwiththeaidofradiometricmethods.Theimportantdatesare:4,600My-theageoftheEarthandSolarSystem3,600My-theearliestlife570My-thefirstappearanceofabundantandvariedorganicforms200My-thebreak-upofthesupercontinent66My-thedisappearanceofthedinosaurs多么富有想象力的比喻！§2-2Basicshapeandclassificationofgeologicalstructure

地质构造的基本形态和分类一、intruductionGeologicalstructureisthestudyofthepermanentdeformationandrockfailurecreatedbythechangesinstressthroughgeologictime.Itisbyfarthemostimportantaspectofgeologyfortheengineertounderstand.Tectonic构造processesareresponsibleforthemanydiscontinuityplanes（不连续面）(fractures裂隙,faults断层,joints节理)thatpermeaterockmassescontrollingtheirstrength,stress-straincharacteristicsandthetransmissionandstorageoffluids.Structuresmaybeconvenientlysubdividedintotwogroups:brittlestructures脆性构造

recordingthebrittle-elasticfailure弹脆性破坏

ofrocksinthepast.Faultsandjointsfallinthisbroadcategory.ductilestructures柔性构造

preservingthepermanentviscoplastic（粘塑性）

deformationofrockthroughoutgeologictime.Foldsandmetamorphicfoliationsaretheexpressionofthistypeofstructure.Themoststrikingfeaturesofrocksasengineeringmaterialsisthattheyarenotsimple,isotropic各向同性的,elastica