测井资料与应用-2

ChinaNationalLoggingCorporationOEPA,2006测井资料与应用(2)GeoscienceCenter,BeijingMay,2009ChinaNationalLoggingCorporationOEPA,20062.3补偿中子测井(NeutronLog)ChinaNationalLoggingCorporationOEPA,2006原理---一种放射性方法测井NEUsourceemitFastNEUFormationatomSlowNEUNEUsourceSLOWDOWNslowNEUnucleiGRcapturedrecordLoggingtool“含氢指数“---由于氢原子(H)核的质量与快中子的质量相当,她对快中子的减速作用很强,因此记录的次生GR值主要与地层孔隙内的”氢”含量(H)有关---NEU被称为“含氢指数“ChinaNationalLoggingCorporationOEPA,2006中子孔隙度*NEU测井记录的是地层孔隙内的含氢量（H），她直接与孔隙度有关----直接指示孔隙度---“中子孔隙度”Φcn•泥质中含有大量的束缚水(大量的“Hydrogen”)----也具有很高的Φcn(无效孔隙度)---NEU曲线不能区分砂，泥岩*水分子(H2O)和石油分子(CnHn)都含有氢元素“H”---油和水都有高的ΦCN---NEU曲线不能用来区分油和水ChinaNationalLoggingCorporationOEPA,2006OilwaterCNshaleCNcurveshowsthesimilarvalueatshale,oilandwaterzonesChinaNationalLoggingCorporationOEPA,2006“挖掘效应气层的”H”浓度远小于油/水层----造成低Φcn的误差ChinaNationalLoggingCorporationOEPA,2006shaleCleansand砂泥岩储层DEN1.7---2.7CN60---0砂岩DEN,CN重合泥岩DEN,CN分离SuitablepresentationscalesDENCNCNDENChinaNationalLoggingCorporationOEPA,2006Suitablescales碳酸岩DEN1.95---2.95CN45----15纯碳酸岩DEN,CN重合泥岩DEN,CN分离ChinaNationalLoggingCorporationOEPA,2006应用•深度校正•碳氢指示•计算孔隙度---需进行“挖掘效应”及泥质影响校正•识别气层---低NEU&DEN,高AC值•识别储层---高NEU&AC,低DEN值•识别致密层---极低NEU&AC,高DEN值ChinaNationalLoggingCorporationOEPA,2006*NEUvaleloggedinopenholeandcasedholehasgoodrepeatability*NEUlogcanbeusedfordepthcorrelationwhenperforatingChinaNationalLoggingCorporationOEPA,2006GaswithlowconcentrationofhydrogenGaswithlowCNvalueGasOilCNChinaNationalLoggingCorporationOEPA,2006*Hardrockwithlowconcentrationofhydrogen*HardrockwithlowCNvalueHardrockCNHardrockChinaNationalLoggingCorporationOEPA,20062.4密度测井(DensityLog)ChinaNationalLoggingCorporationOEPA,2006原理---一种放射性测井*DEN仪器使用Cs137放射源产生并发射中等能量的GR射线*GR与地层中的电子相碰撞–发生康普顿散射---GR射线失掉部分能量•仪器记录低能GR射线*受减速作用而成为低能GR射线的记量与地层岩石的密度有关Cs137GRreleaseGRGRelectronRecordbytoolChinaNationalLoggingCorporationOEPA,2006不同岩石的体积密度及Pe值ChinaNationalLoggingCorporationOEPA,2006Mudcake补偿密度测井ChinaNationalLoggingCorporationOEPA,20062.4.2密度孔隙度体积密度:b=(1ø)ma+øfø=式中,b–测井密度值,ma–骨架密度值,f–流体密度值(mab)mafChinaNationalLoggingCorporationOEPA,2006Z–密度仪器记录有光电吸收指数(PE),她对岩性很敏感ObviousdifferentofPEvaluefordifferentlithology岩性指示器---PEChinaNationalLoggingCorporationOEPA,2006GaswithverylowdensityGaszoneswithlowdensityvalue气的影响ChinaNationalLoggingCorporationOEPA,2006shaleCleansandShale–sandreservoirsDEN1.7---2.7CN60---0SandzonesDEN,CNoverlayShalezonesDEN,CNseparateSuitablepresentationscalesDENCNCNDENChinaNationalLoggingCorporationOEPA,2006泥浆对PE的影响Heavydensitymud(withbarite)willaffectPeresponseExample:Pe4,randomcurveandcan’tbeusedtoidentifylithologyPeChinaNationalLoggingCorporationOEPA,20062.4.5应用•计算孔隙度Φ•识别岩性ChinaNationalLoggingCorporationOEPA,2006假定地层含泥,孔隙中充满流体体积密度:b=(1VshØ)ma+Vshsh+ØfSo,Ø=Øoilwatershalematrix(mab)Vsh(mash)maf2.4.4影响泥质影响ChinaNationalLoggingCorporationOEPA,2006应用岩性指示曲线Pe识别岩性*Pe不受地层流体的影响,对岩性灵敏*Pe与别的资料综合利用更能有效识别岩性.