工程地质课件

Introduction

緒論

1thedefinitionofcivilengineeringgeology

土木工程地質的基本概念

2Thepositionofengineeringgeologyinthecivilengineeringcoursesystem(

工程地質在土木學科體系中的位置)3themainsubstanceaboutengineeringgeology(工程地質學研究的具體內容)

4theimportanceofGE(學習意義)5Demands(requirements)（要求）Themaintopicsinintroduction

緒論中的主要內容thedefinitionofengineeringgeology

（工程地質學的基本概念）

(1)Engineeringgeologyisaboutapplyingallbranchesofthegeosciences(地質學)toassurethesafety,efficiency,andeconomyofengineeringandenvironmentalprojects.

（2）EngineeringGeologyisdevotedtotheinvestigation（勘察）,studyandsolutionoftheengineeringandenvironmentalproblemswhichmayariseastheresultoftheinteractionbetweengeologyandtheworksandactivitiesofmanaswellastothepredictionandthedevelopmentofmeasuresforpreventionormediationofgeologicalhazards（地質災害）(3)Whicharemainlyconcernedwiththegeologicalproblemsencounteredincivilengineering.Itsmaintasksistoinvestigateandevaluatethegeologicalengineeringproblems,providethebasicinformationfortheplan,designandconstructionofthecivilengineering.2Thepositionofengineeringgeologyinthecivilengineeringcoursesystem(

工程地質在土木學科體系中的位置Corecourse（基礎課程）

→

Differentialandintegral→algebra→probabilityandstatistics

→

engineeringmath→Physics→ChemicalTechnologicalcorecourse（專業基礎課程）

→

Surveying→engineeringmapping→materials→surveying

→

engineering（工程測量）

→engineeringgeology(工程地質)→soil(rock)mechanics（岩土力學）

→

theoreticalmechanics→materialmechanics→structuremechanics→elasticorplastic（彈塑性）

→hydrolicmechanics（水力學）Specializedcourse（專業課程）

→concretestructure（砌體結構

→steelstructure（鋼結構）

→roadengineering（道路工程）

→thedesignofroadsurvey（道路勘測設計）→bridgeengineering(橋樑工程)→trafficengineering(交通工程)→foundationengineering(基礎工程)→constructiontechnology(building…)施工技術→engineeringmanagementandbudgetestimation→engineeringbiddingrehabilitation(building、brigde、road…)（工程招投標）3themainsubstanceaboutengineeringgeology(工程地質學研究的具體內容)ThepurposeofstudyingGEistoprovidegoodgeologicalenvironmentforengineeringortoevaluateandforecasttheengineeringgeologicalproblemsthatmayoccurredintheperiodoftheservicetime（服務期）ofthebuilding.onthisbase,togivetheeffectiveengineeringpreventionmethods.◆thestudyabouttopographyandlandforms

（地形地貌）◆thestudyaboutthefundamentalengineering

properties(physicalandmechanics)ofsoilsandrock(岩土工程性質）◆geologicalstructure（地質構造）

GeologicalEnvironment(GeologicalCondition)

地質環境和地質條件的含義4theimportanceofGE(學習意義)◆hydrogeology(水文地質：地下水條件)◆theanalysesofengineeringgeologicalproblems

（工程地質問題分析）

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

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

第一節地球的內部結構

ThisregionisthincomparedtotheotherlayersintheEarth.

Itvariesinthicknessfrom10kmdeepto65kmdeep.

Thecrustismadeupoflighterrocksthat"float"ontopofthemantle.

This

layerincludesthecontinentsaswellastherockundertheoceans.

wehavebuiltmanydeepminesbutNONEhaveyetreachedthemantle!TheCrust(地殼)軟流圈岩石圈上地慢有關岩石圈(lithosphere)StructureoftheEarth‘scrustandtopmostlayeroftheuppermantle（上地慢）.Thelithosphere（岩石圈）consistsoftheoceaniccrust,continentalcrust,anduppermostmantle.Beneaththelithosphereistheasthenosphere（軟流圈）.Thislayer,whichisalsopartoftheuppermantle,extendstoadepthofabout200kilometers.Sedimentarydepositsarecommonlyfoundattheboundariesbetweenthecontinentalandoceaniccrust.Thisregionliesunderthecrustandisapproximately2900kmthick.

Themantleismuchdenserthanthecrust(whichiswhythecrustfloatsontop)andhasatexturemuchliketar.

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

TheouterpartiscalledtheOuterCore.

Itisabout2100kmthickandmadeofliquidnickelandiron.

TheinnerpartiscalledtheInnerCoreanditistherealcentreoftheEarth.

Thispartisabout2800kmindiameterandismadeofsolidironandnickel.TheCore:SECTION1-2PlateStructureTheory

第二節板塊構造理論1PacificPlate(太平洋板塊)

2NorthAmericanPlate（北美板塊）

3SouthAmericanPlate

（南美板塊）4EurasianPlate（歐亞板塊）

5AfricanPlate（非洲板塊）

6IndoAustralianPlate（澳印板塊）

7AntarcticPlate（南極州板塊）

1PacificPlate2NorthAmericanPlate

3SouthAmericanPlate4EurasianPlate

5AfricanPlate6IndoAustralianPlate

7AntarcticPlate

板塊構造理論板塊的形成（大陸漂移）德國氣象學家阿爾弗雷德·魏格納（AlfredWegener）

海底擴張理論（TheoryofOceanFloorSpreading）海底擴張的證據（沉積物的年齡）海底擴張的結果（喜馬拉雅山的形成）

海溝的形成岩石迴圈的概念SECTION1-3:TheconceptofGeologicalAction（function）第三節地質作用的概念1Whatisgeologicalaction（基本定義）

meantheactionsthatmakealterationforthecomposition，structure,shapeoftherockcyclebecauseofthenaturaldynamics.

CrustmovementSunnaturaldynamicsWindglaciergravitationwater2

TheclassificationoftheGeo.Action

（地質作用分類）

(1)

outer-dynamicsgeologicalaction(外動力地質作用)

dynamicsourceisfromthesun,gravity,attractionforcebetweensunandmoon.

▶Weathering（風化作用）

→theRockisdestroyedattheplacewhereitwasformedbecauseoftheouterdynamics.

▶Erosion（剝蝕作用）

→Rockbody岩體isseparatedfromitsmotherrock

（母岩）becauseofthewater,wind,glacier.

▶Carrying(搬運作用)→theprocessthatrockiscarriedfromoneplacetoantherplace.Becauseof…

▶

Sedimentation（沉積作用）

→theprocessinwhichthecarryingmaterialssinktothebottomofgroundwhenthepowerofgravityofthematerialsisbiggerthanthecarryingforce.

▶

Rock-formationaction（成岩作用）

→theprocessthatthematerialssunktogroundsurfacetobecomehardorsolidrockbody.

▶Crustmovement（地殼運動）

▶B:Magmatism(magmaticactivities)岩漿作用

(magmaticintrusionandvolcaniceruption)

▶Earthquake（地震作用）

(2)Inner-dynamicsgeologicalaction(內動力地質作用)(thedynamicssourceisfromearth▶Metamorphism（變質作用）

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

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

Crystalform（晶形）

♥

Hardness（硬度）

(relativetoasteelbladeoryoufingernail),

♥

colour(真色，假色，它色)

♥

Luster（光澤）

♥

Streak(條痕)

(thecolourwhenamineralisgroundtoapowder).

♥cleavage（解理）Physicalpropertiesofmineralsincludefeaturessuchas：Quartzishard-itcaneasilyscratchasteelknifeblade.Inmanyrocks,quartzgrainsareirregularinshapebecausecrystalfacesarerareandquartzdoesnothaveacleavage(ie,itdoesnotbreakonregularflatfaces).1Quartz(石英):Quartzisaglassylooking,transparentortranslucentmineralwhichvariesincolourfromwhiteandgreytosmoky.Whenthereareindividualcrystalstheyaregenerallyclear,whileinlargermassesquartzlooksmoremilkywhite.油脂光澤Feldsparisalsohardbutcanbescratchedbyquartz.Feldsparinigneousrocks（火成岩）formswelldevelopedcrystalswhichareroughlyrectangularinshape,andtheycleaveorbreakalongflatfaces.Thegrains,incontrasttoquartz,oftenhavestraightedgesandflatrectangularfaces,someofwhichmeetatrightangles.2Feldspar（長石）:Feldsparistheothercommon,light-colouredrock-formingmineral.Insteadofbeingglassylikequartz,itisgenerallydulltoopaque（不透明）withaporcelain-likeappearance.Colourvariesfromred,pink(orthoclase正長石),andwhitetogreen,grey(plagioclase斜長石).Plagioclase斜長石Orthoclase正長石Themostcommonamphiboleishornblende（角閃石）.Hornblendeisquitesimilartoaugite（普通輝石）inthatbotharedarkminerals,howeverhornblendecrystalsaregenerallylonger,thinnerandshinierthanaugiteandthemineralcross-sectionsarediamond-shaped.hornblende（角閃石）3Amphibole（閃石）Themostcommonpyroxenemineralisaugite.Augiteisgenerallydarkgreentoblackincolourandformsshort,stubby（短而粗）crystalswhich,ifyoulookatanend-onsection,havesquareorrectangularcross-sections.Pyroxene（輝石）4Pyroxene輝石Talcoccursingranular（粒狀的）orfoliated（片狀的）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橄欖石Micaiseasilydistinguishedbyitscharacteristicofpeelingintomanythinflatsmoothsheetsorflakes（薄片）.Thisissimilartothecleavageinfeldsparexceptthatinthecaseofmicathecleavageplanesareinonlyonedirectionandnorightanglefacejoinsoccur.Micamaybewhiteandpearlyordarkandshiny.7Mica雲母8Gypsum(plasterstone,石膏)9Kaolinite(高嶺石)10Montmorillonite（蒙脫石）11Watermica（伊利石）§2-2:Rock(岩石)(一種或多種礦物組成的集合體)

一、Theclassificationofrockaccordingtothecauseofformationigneousrock（岩漿岩）

(magmarock)sedimentaryrock（沉積岩）

metamophicrock（變質岩）岩石二、Igneousrock1theformationofigneousrock:DeepwithintheEarth,rockiskeptinamolten（融熔的）stateduetoextremetemperatureandpressure.

Thismoltenrockiscalledmagma（岩漿）.

Themagmaisconstantlymovingandsometimesmovesitswaytothesurfacethroughthecracks（裂縫）inthesolidrock.

Onceitreachesthesurface,itiscalledlava（熔岩）.

Thelocationitpushesthroughtothesurfaceiscalledavolcano（火山）.

Theopeninginthevolcanothatthelavaeruptsoutofiscalledavent(出口).

Formanyvolcanos,thereismorethanonevent.

Oftenvolcanoshaveafunnel（漏斗）shapewithapitatthetop.

Thispitiscalledavolcaniccrater（火山口）.

Ifthiscraterbecomesverylarge,thewallsofthecratermightcollapsetoproduceafeaturecalledacaldera（噴火山口）HowIgneousrockrockIsFormedPyroclasticash(火山灰)Batholith岩基Captivemass俘虜體laccolith岩盤岩牆Rockwall岩株Volcanoneck火山頸Lavaflow岩流theformationstateofigneousrock（岩漿岩的產狀）Sill岩床3theclasscificationofigneousrock（岩漿岩的分類）

（1）Accordingtotheformationstate(按產狀)

◈IntrusiveIgneousRocks（侵入岩）

-usuallymediumtocoarsegrainedtextureduetoslowcooling.Typicallylightcoloured.

◈ExtrusiveIgneousRocks（噴出岩）

-glassyorfine-grainedduetorapidcooling.Mayhavevoidsduetodegassingofthemagma.Typicallydarkcoloured.(2)AccordingtotheSilicaContentandMineralComposition(根據二氧化矽含量)

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

◈IntermediateIgneousRocks（中性岩）

silica50-65%byweight,composedmainlyoffeldspars,somemafic（鐵鎂質的minerals,withsomequartz.

◈BasicIgneousRocks（基性岩）

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

（岩漿岩描述）

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

◈

porphyriticgranite(花崗斑岩)

shallowintrusiverock（淺成侵入岩）

moderatecrystallization（中等結晶）

porphyriticstructure斑狀結構

quartz-feldspar-blackmica花崗斑岩

◈rhyolite

（流紋岩）

Rhyoliteisverycloselyrelatedtogranite.Thedifferenceisrhyolitehasmuchfinercrystals.Thesecrystalsaresosmallthattheycannotbeseenbythenakedeye.Rhyoliteisanextrusiveigneousrockhavingcooledmuchmorerapidlythangranite,givingitaglassyappearance.Themineralsthatmakeuprhyolitearequartz,feldspar,mica,andhornblende.Rhyolite流紋岩

◈Diorite(閃長岩)1abyssalintrusiverock2wellcrystallization3feldspar,quartz,amphibole◈

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

◈pyroxenire(輝岩)

1abyssalintrusiverock2wellcrystallization3amphibole,phyroxenefeldspar

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

(sio2<45%)2abyssalintrusiverock（深成岩）

3wellcrystallization（結晶好）

4olivine；pgroxene◈olivinerock(橄欖岩)◈Obsidian黑耀岩Obsidianisaveryshinynaturalvolcanicglass.Whenobsidianbreaksitfractureswithadistinctconchoidal（貝殼狀的）fracture.Noticeinthephototothelefthowitfractures.Obsidianisproducedwhenlavacoolsveryquickly.Thelavacoolssoquicklythatnocrystalscanform.Whenpeoplemakeglasstheymeltsilicarockslikesandandquartzthencoolitrapidlybyplacingitinwater.Obsidianisproducedinnatureinasimilarway.Obsidianisusuallyblackoraverydarkgreen,butitcanalsobefoundinanalmostclearform.Pumiceisaverylightcolored,frothy（起泡的）volcanicrock.Pumiceisformedfromlavathatisfullofgas.Thelavaisejectedandshotthroughtheairduringaneruption.Asthelavahurtles（急飛）throughtheairitcoolsandthegasesescapeleavingtherockfullofholes.◈Pumice（浮石）Pumiceissolightthatitactuallyfloatsonwater.Hugepumiceblockshavebeenseenfloatingontheoceanafterlargeeruptions.Somelavablocksarelargeenoughtocarrysmallanimals.三、sedimentaryrock（沉積岩）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（化學岩）

whicharecarriedinaqueoussolution.Salt(halite)isanexampleofachemicalprecipitate.·

▦3

Organicorbiogenicsediments（有機岩）

precipitatedoraccumulatedbybiologicalagents.Manyorganismspromotetheprecipitationofcalcitetoformbiogenicallyprecipitatedcalcareous（含鈣的）muds.3Thetextureandstructureofsedimentaryrock

沉積岩的結構和構造沉積岩的層理構造平行層理斜層理波狀層理印模粒序層理交叉層理沉積岩的結構特徵砂粒孔隙膠結物砂粒粘粒粉粒鐵餅形的Sphericity球形度[sfe’risiti]4thedescriptionofsedimentaryrockConglomeraterocksaresedimentaryrocks.Theyaremadeupoflargesedimentslikesandandpebbles（鵝卵石）.Thesedimentissolargethatpressurealonecannotholdtherocktogether;itisalsocementedtogetherwithdissolvedminerals.◈

gravelstone(conglomerate)礫岩(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(高嶺石)montorillonite（蒙脫石）

watermica（伊利石）MineralCompositionShalerockisatypeofsedimentaryrockformedfromclaythatiscompactedtogetherbypressure.Theyareusedtomakebricks◈

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

limestone石灰岩◈

dolomiterock白雲岩color:white-greymineral:dolomit◈

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

Thetypeofmetamorphicrockisdeterminedbytheparentrock（母岩）andtheP/Tconditions.Ingeneral,metamorphismcauses:GrowthofnewmineralsDeformationandrotationofmineralgrainsRecrystallizationofmineralsaslargergrains1theformationandclassificationofMetamorphicrocks變質岩的形成接觸變質岩的形成區域變質岩的形成2thedescriptionofMetamorphicrocks

◈

Marble

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

Marblehasmanycolorvariancesduetotheimpurities(雜質)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

地質構造§2-1geologicaltimeandChronologicalscale

地質年代與地質年代表

一、GeologicalTime

Geologicaltimeisamethodoforderingandmeasuringpastevents.Theorderingofeventsusesagroupofobservationalmethodsknownas:

1Absolutedatingmethods(絕對年代法)

2Relativedatingmethods（相對年代法）1AbsolutedatingmethodsAbsolutedatingmethodsarethosethatgenerateanageinyears.Therearetwoprincipalmethods:oneisthemethodwhichrelyoneventinthegeologicalrecordwithverystrongannualcyclicity(週期性),suchastreegrowthrings,coralgrowthcyclesvarves（紋層）

(annualclaysedimentlayers).AnotherMethodsismorecommonlyusednowdayswhichrelyonthedecayofnaturallyoccurringradiogenicisotopes:

Radiometricdatingisnotwithoutdifficultiesbutisbyfarthemostwidespreadmethodappliedtodetermineabsoluteagesbetween100and4500My.Uranium(鈾),Thorium（釷）

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

♣stratasuperpositionmethod（地層層序法）♣fossilsuccessionmethod（化石演變法）♣themethodofrocklayerscontactrelation

（岩層接觸關係法）.

♣Theprincipleofsuperpositionstatesthatolderbedsarecoveredbyyoungerbeds.Inotherword,theyoungestunitisusuallyatthetopinasedimentarysequence.TheyoungestlayerTheoldestlayer

♣Theprincipleoffossilsuccessionstatesthatorganismsevolvethroughtimesothatparticularformscanbeusedasagemarkerswherevertheyarefound.

♣

Themethodofrocklayerscontactrelationstatesthatthecontactrelationsamongrocklayersisthehistoryrecordsofcrustmovement,magmaactivities.Sogeologicaleventscanbeorderedbytherelationofrocklayers,theseincludes：①therelationsamongsedimentaryrock,

（沉積岩之間的接觸關係）②therelationsamongtheigneousrock,（岩漿岩之間的接觸關係）③therelationbetweensedimentaryrockandigneousrock.（沉積岩和岩漿岩之間的接觸關係）①TherelationsamongsedimentaryrockTherelationsamongsedimentaryrockcanbedividedinto：

conformity（整合）

Unconformity（不整合）.Theconformitymeansthatstratawasformedinastablesedimentaryenvironment,thedipandstrikeofstrataarebasicallythesame.conformity（整合接觸關係）Unconformity（不整合）.Theunconformitymeanthereisabreakinsedimentation,aperiodoferosionoranepisodeofdeformation,Unconformitiesrangefromminorerosionalbreakstostrongangulardiscordancesinbedding.Anunconformityindicatesaperiodwherenorockrecordisaccumulated.Theyaretime-breaksofindeterminatelength.整合接觸平行不整合接觸角度不整合接觸②therelationsamongtheigneousrock,岩漿岩之間的接觸關係Cross-cuttingrelationshipsamongigneousrocksindicatethatintrusionrocksmustbeyoungerthantherockstheycut.③therelationbetweensedimentaryrockandigneousrock.Cross-cuttingrelationshipsbetweenigneousrocksandsedimentaryrockIndicatethatsedimentaryrockincludedpebblesandfragmentsmustbeolderthanthehostrockcontainingthem.二、ChronologicalscaleThegeologictimescalewasoriginallyasetofrelativedatesbutthevariouseons（宙）,eras（代）,periods（紀）andepochs（世）havenowbeenaccuratelydatedwiththeaidofradiometricmethods.Theimportantdatesare:4,600My-theageoftheEarthandSolarSystem3,600My-theearliestlife570My-thefirstappearanceofabundantandvariedorganicforms200My-thebreak-upofthesupercontinent66My-thedisappearanceofthedinosaurs多麼富有想象力的比喻！§2-2Basicshapeandclassificationofgeologicalstructure

地質構造的基本形態和分類一、intruductionGeologicalstructureisthestudyofthepermanentdeformationandrockfailurecreatedbythechangesinstressthroughgeologictime.Itisbyfarthemostimportantaspectofgeologyfortheengineertounderstand.Tectonic構造processesareresponsibleforthemanydiscontinuityplanes（不連續面）(fractures裂隙,faults斷層,joints節理)thatpermeaterockmassescontrollingtheirstrength,stress-straincharacteristicsandthetransmissionandstorageoffluids.Structuresmaybeconvenientlysubdividedintotwogroups:brittlestructures脆性構造

recordingthebrittle-elasticfailure彈脆性破壞

ofrocksinthepast.Faultsandjointsfallinthisbroadcategory.ductilestructures柔性構造

preservingthepermanentviscoplastic（粘塑性）

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