地球物理测井方法原理和应用

地球物理测井方法原理和应用总目录第一讲：绪论第二讲：普通电阻率法测井第三讲：聚流电电阻率测井第四讲:自然电位测井方法原理及应用第五讲：感应测井第六讲:声波测井第七讲:自然伽马测井方法原理及应用第八讲:中子测井方法原理及应用第一讲：绪论一、地球物理测井的基本概念二、地球物理测井能解决什么问题?三、地球物理测井包括哪些内容？四、地球物理测井的发展历史五、地球物理测井在地球物理探测技术中的位置矿场地球物理油矿地球物理钻井地球物理勘探地球物理测井:钻孔中进行的各种地球物理探测方法的统称.1927年由法国Schlumbeger公司的创始人Schlumbeger兄弟俩创立的.地球物理测井是用各种专门的仪器放入井内,沿井身测量井孔剖面上各种物理参数随井深的变化曲线,并根据测量结果进行综合解释,用于判断岩性、确定油气层及其它矿藏的一种间接手段.测井工作分为两个阶段:野外资料录取阶段和资料处理解释阶段.Theboreholeenvironment•Theboreholeenvironmentinwhichloggingmeasurementsaremadeisofsomeinterestfromthestandpointofloggingtooldesignsandtheoperatinglimitionsplaceduponthem.•itisimportantintermsofthedisturbanceitcausesinthesurroundingformationinwhichpropertiesarebeingmeasured.TheBoreholeEnvironment•Somecharacterizationoftheboreholeenvironmentcanbemadeusingthefollowingsetofgeneralizations:•Welldepths•Thedeviationoftheborehole,whichisbetweenandonshore,andbetweenandoffshore.•Thetemperature,atfulldepth,rangesbetweenandF•Thedrillingfluid,ormud.Thesalinityofthedrillingmudrangesbetween3000and200,000ppmofNaCl,Thiscausesinvasionofaporousandpermeableformationbythedrillingfluid.052040100300TheBoreholeEnvironment•Toaccountforthedistortionwhichisfrequentlypresentwithelectricalmeasurements,asimplifiedmodeloftheborehole/formationhasevolved,whichisshownschematicallyinFig.2-4Itconsiderstheinvadedformationofinterest,ofresistivitytobesurroundedby“shoulder”bedsofresistivitythemudcakeofthicknessandresistivityThenextannularregionofdiameteristheflushedzonewhoseresistivityisdonatedbytheuninvadedorvirginzonewithresistivitytRsRmchmcRidxoRtRFigure2-4.Schematicmodeloftheboreholeandformationusedtodescribeelectricloggingmeasurementsandcorrections.第一讲：绪论一、地球物理测井的基本概念二、地球物理测井能解决什么问题?三、地球物理测井包括哪些内容？四、地球物理测井的发展历史五、地球物理测井在地球物理探测技术中的位置可以解决的问题:1.油气储层的评价问题2.相关的地质问题3.工程问题及地层的机械性能4.油气开发问题5.为地面地球物理勘探资料解释提供参数6.与其它资料结合进行储层空间描述与盆地分析IntroductionThissectionpresentsageneraloverviewoftheproblemofloginterpretationandexaminesthebasicquestionsconcerningaformation’spotentialhydrocarbonproductionwhichareaddressedbywelllogs.Theboreholeenvironmentisdescribedintermsofitsimpactontheelectricalloggingmeasurements,andallofthequalitativeconceptsnecessaryforsimpleloginterpretationarepresented.Thelogformatconventionsarepresented,andanexampleisgivenwhichindicatestheprocessoflocatingpossiblehydrocarbonzonesfromlogmeasurements.Theprocessofextractingpetrophysicalparametersfromtheloggingmeasurementsisthesubjectofsubsequentchapters.RudimentaryWellSiteInterpretation•Loginterpretation,orformationevaluation,requiresthesynthesisofloggingtoolresponsephysics,geologicalknowledgeandauxiliarymeasurementsorinformationtoextractthemaximumpetrophysicalinformationconcerningsubsurfaceformations.•Inthissection,asubsetofthisprocedureisconsidered:wellsiteinterpretation•Thissubsetreferstotherapidandsomewhatcursoryapproachtoscanninganavailablesetofloggingmeasurements,andtheabilitytoidentifyanddrawsomeconclusionaboutzonesofpossibleinterest.RudimentaryWellSiteInterpretation•Themostimportantquestionstobeansweredbywellsiteinterpretationare:1.Doestheformationcontainhydrocarbons?2.Ifso,whatisthequantitypresent?3.Arethehydrocarbonsrecoverable?•Inordertoseehowloggingmeasurementscanprovideanswerstothesequestions,afewdefinitionsmustfirstbesetout.1.porosityisthatfractionofthevolumeofarockwhichisnotmatrixmaterialandmaybefilledwithfluids.Fig.2-1illustratesaunitvolumeofrockTheporespacehasafractionalvolumedenotedby,thematrixmaterialoccupiestheremainingfractionofthevolume,1RudimentaryWellSiteInterpretation•Figure2-1.Aunitvolumeofformationshowingtheporosityandthefractionalporevolumeofwater.Thefractionalvolumeofhydrocarbonsis.(1)wSwSNote:thefractionalvolumeoccupiedbythewaterisgivenbytheproduct,andthetotalfractionofformationoccupiedbytheoilby2.Watersaturation,isthefractionoftheporositywhichcontainswater.ThisfractionalvolumeisalsoindicatedinFig.2-1.3.Oilsaturation,isgivenbyRudimentaryWellSiteInterpretationwSwSoS•Sinceoneoftheprincipalloggingmeasurementsusedforthequantificationofhydrocarbonsaturationiselectricalinnature,itisnecessarytomentionsomeoftheterminologyusedtodescribethesemeasurements.Theresistivityofaformationisameasureoftheeaseofelectricconduction.Resistivity,acharacteristicakintoresistance,isdiscussedinmuchmoredetaillater.Replacingtheconductivebrineofaporousmediumwithessentiallynonconducinghydrocarbonscanbeexpectedtoimpedetheflowofcurrentandthusincreaseitsresistivity.RudimentaryWellSiteInterpretation•Theresistivityoftheundisturbedregionofformation,isdenotedbyisderivedfrommeasurementsthatyieldanapparentresistivity.Thesemeasurementscanthenbecorrected,whennecessary,toyieldthetrueformationresistivity.•Intheregionsurroundingthewellbore,wheretheformationhasbeendisturbedbytheinvasionofdrillingfluids,theresistivitycanbequitedifferentfrom.Thiszoneiscalledtheinvadedorflushedzone,anditsresistivityisdonatedby.RudimentaryWellSiteInterpretationtRtRxoR•Twootherresistivities:1.theresistivityofthebrine,whichmaybepresentintheporespace.2.theresistivityofthefiltrateofthedrillingfluid,,whichcaninvadetheformationnearthew