测井资料与应用 -3

ChinaNationalLoggingCorporationOEPA,2006测井资料与应用(3)GeoscienceCenter,BeijingMay,2009ChinaNationalLoggingCorporationOEPA,20062.5声波测井(AcousticLog)ChinaNationalLoggingCorporationOEPA,20062.5.1测量原理*声波发生器激发声波*声波沿井壁滑行传播*两个接收探头记录声波全波列信号*测量声波传播经过两个接收探头所用的时间△tChinaNationalLoggingCorporationOEPA,2006FullwaveformConventionalacousticlogrecordP(compressional),S(shear)andstoneleywaveformcompressionalChinaNationalLoggingCorporationOEPA,2006常规声波测井一般提供声波时差ΔtGRΔtChinaNationalLoggingCorporationOEPA,2006不同的地层具有不同的声波速度和时差ΔtChinaNationalLoggingCorporationOEPA,20062.5.3声波孔隙度•通常地层岩石骨架的声速都远大于孔隙中流体的声速•高孔隙地层饱含更多的流体,其声速将较低*记录的总t=骨架t+孔隙流体t*声波速度(或Δt)与孔隙度紧密相关soundsoundChinaNationalLoggingCorporationOEPA,20062.5.4应用•计算孔隙度•估算地层破裂压力•地层出砂分析•计算渗透率•纵合密度测井资料制作合成地震剖面ChinaNationalLoggingCorporationOEPA,2006•Wyllie平均时间公式(WTA)最常用的孔隙度公式:•Øs=式中,△tma纯地层骨架的声波时差;△tf孔隙流体的声波时差;Cp压实校正系数.Cp(△tf△tma)(△tc△tma)ChinaNationalLoggingCorporationOEPA,2006压实校正•固结不好(欠压实)的砂岩Δt较高,用其计算的孔隙度偏高(≈28-50%),通常需进行压实校正•压实校正公式:致密地层Cp=1固结不好(欠压实)地层压实系数Cp≈0.8–1.3pmafmaCtttt1100)(CtCshpChinaNationalLoggingCorporationOEPA,2006压实校正图版范例砂岩Δt=110µs/ft不校正:Φ=40%选择Cp=1.5:Φ≈27%ChinaNationalLoggingCorporationOEPA,2006泥质影响校正)1()(shmashfVtVttshmafmaVttttshacVshpmafmaVCtttt1固结好(压实)纱岩:固结差(非压实)纱岩:简单公式:ChinaNationalLoggingCorporationOEPA,2006油,气影响校正油,气的t大于水---油/气层处理出的ΦAC偏大油,气影响校正系数:气层Φt=0.7×ΦAC油层Φt=0.9×ΦACChinaNationalLoggingCorporationOEPA,2006GRCleansandcleansand:Δtlog≈125µs/ftΔtm≈55.5µs/ftΔtf≈189µs/ftCp=1.2Vsh≈0.1(10%)Φ≈(125-55.5)/(189-55.50)/1.2–Vsh≈69.5/133.5/1.2–0.1≈0.43-0.1≈0.33(%)Usecrossplot:Φ≈0.3%ΦcalculationUsingacousticdataalongΔtΦChinaNationalLoggingCorporationOEPA,2006研究岩石的物理特性*可用AC资料计算出许多岩石的弹性摸量参数*着些弹性摸量参数可用来评价储层压裂,出砂等问题ChinaNationalLoggingCorporationOEPA,2006ChinaNationalLoggingCorporationOEPA,2006BoreholeBreakoutGoodBorehole井壁稳定性分析ChinaNationalLoggingCorporationOEPA,2006地层出砂分析SandingPotentialPredictionChinaNationalLoggingCorporationOEPA,2006用斯通利波计算渗透率*Permeabilityisaimportantparameterforreservoirevaluation*Permeabilityisdifficulttocalculatedaccurately*StoneleywavecanbeusedtocalculatepermeabilitymoreaccuratelyChinaNationalLoggingCorporationOEPA,2006合成地震剖面ChinaNationalLoggingCorporationOEPA,2006ChinaNationalLoggingCorporationOEPA,2006ChinaNationalLoggingCorporationOEPA,20062.6电阻率测井ChinaNationalLoggingCorporationOEPA,2006AMN0测量间距电源电压表B测井仪器电场电阻率测井示意图ChinaNationalLoggingCorporationOEPA,2006不同地层的电阻率•松软地层(泥质砂岩)0.5ohmm-50ohmm.•致密地层(碳酸岩)10ohmmto1000ohmm.•喷发岩(硬石膏)可高达几千到上万ohmmChinaNationalLoggingCorporationOEPA,2006PresentationLinearscalelogarithmicscaleChinaNationalLoggingCorporationOEPA,2006Sandscale:0.02-200Limestonescale:2-2000ChinaNationalLoggingCorporationOEPA,20062.6.3DualLateralResistivityToolInvestigatedepth--deeplogRD80in--shallowlogRS60inUsedtocalculatetrueformationRt&SWChinaNationalLoggingCorporationOEPA,2006ReceiverGroundloopTransmitter2.6.4InductionToolSchematic•Conductivitylog•Investigatedepth--deeplogRD60in--shallowlogRS40in•UsedtocalculatetrueformationRt&SWChinaNationalLoggingCorporationOEPA,2006*8Rtcurveswithdifferentinvestigationdepth(10–120in)*Theloggingcurvesseparateinthepermeablezone.*Theinvasionprofileshowsustheflushedzone,transitionzoneandvirginzone.HDIL(highresolutiondigitalinductionlog)ChinaNationalLoggingCorporationOEPA,2006•Usefocusedcurrent*Veryshallowinvestigation(2-12in)*MeasureRtofflushedzone(RXO)*Usedforevaluationofinvadedaffection2.6.5聚焦及微电阻率测井ChinaNationalLoggingCorporationOEPA,20062.6.6环境影响InvadedzoneNoneinvadedzone泥浆侵入对地层的污染在泥浆侵入条件下的测井响应ChinaNationalLoggingCorporationOEPA,2006主要的环境影响●井眼垮塌●电阻率差异大的围岩●泥浆侵入.ChinaNationalLoggingCorporationOEPA,2006Theaffectionofbedthickness•Logpg7-4,fig7-5LowerRtofsurroundingbedHighRtofsurroundingbedChinaNationalLoggingCorporationOEPA,2006BedthicknessCorrection(Inductionlog)Bedthickness6ftNocorrectionThinnerbedsneedmorecorrectionDifferentRsneeddifferentcorrectionChinaNationalLoggingCorporationOEPA,2006ChartforboreholecorrectiontoduallateralExamplegive:Rm=1ΏmRD=10Ώmborehole=11inRLLDcorr≈10×1.4≈14(Ώm)ChinaNationalLoggingCorporationOEPA,2006WaterzoneSaltymud(RmRw,lowRtinvaded):RaRxoRmFreshwatermud(RmRw,highRtinvaded):RaRxoRmOilzoneSaltymud(RmRw,lowRtinvaded):RaRxoRmFreshwatermud(RmRw,highRtinvaded):RaRxoRmRa–apparentlogresistivityRxo–flushedzoneresistivityRm–mudresistivityInvasionaffectionLowresistivityinvadedHighresistivityinvadedChinaNationalLoggingCorporationOEPA,2006HighresistivityinvasionRw=0.04Ωm/29˚CRmf=1.16Ωm/28.5˚CRt(shallower)Rt(deeper).ChinaNationalLoggingCorporationOEPA,2006LowresistivityinvasionRw=1.14Ωm/30˚CRmf=0.16Ωm/27.8˚CRt(shallower)Rt(deeper).ChinaNationalLoggingCorporationOEPA,20062.6.7应用主要用途是计算含水饱和度,识别油,气水层油/气的电阻率高于水致密岩石(钙,硬石膏,白云岩等)电阻率也很高,Rt不能单独用来识别油,气,水层ChinaNationalLoggingCorporationOEPA,2006OilwatergasoiloilSwSwChinaNationalLoggingCorporationOEPA,2006HardrockwithhigherRtvalueHardrockCNChinaNationalLoggingCorporationOEPA,2006ThankYou!