5油气层损害诊断

油气层损害诊断康毅力西南石油学院石油工程学院油井完井技术中心2005年09月15日提纲0、损害机理及诊断概述1、DST测试2、测井分析3、井史分析4、相邻井生产动态对比5、压力不稳定试井分析6、节点系统分析7、生产效率剖面8、生产测井9、岩心分析油气层损害机理润湿性改变水锁凝析液锁液相圈闭（水，油）气锥或水锥毛管压力的改变乳状液堵塞粘土膨胀微粒运移云母解体无机垢注ＣＯ２导致的无机垢酸化引起的二次沉淀碳酸盐溶解—沉淀酸渣有机垢—石蜡，沥青沉积外来固相的堵塞油气层固相物堵塞，出砂细菌损害应力损害四大类型物理损害化学损害生物损害热力损害油气层损害类型及其分布结构大类亚类三级四级作业环节微粒运移钻完井液固相固相侵入注入流体固相水基工作液油基工作液相圈闭泡沫状油钻井完井、增产改造、修井、注水注气、EOR岩面釉化机械损害岩粉挤入气体流体钻井、斜井钻井射孔损害压实损害射孔完井剪切膨胀物理作用应力损害地层压实钻井、油气生产敏感性损害粘土矿物损害非粘土矿物损害岩石—外来流体不配伍处理剂吸附聚合物、阴离子有机垢沉积石蜡、沥青沉积无机垢沉积盐类沉积、水合物、类金刚石物地层流体—外来流体不配伍乳状液堵塞化学作用润湿性反转钻井完井、增产改造、修井、注水注气、EOR分泌聚合物腐蚀损害生物作用流体酸性化注水和EOR过程为主矿物溶解矿物转化热力作用润湿性变化热力采油为主损害描述类型天然损害（生产井）诱发损害（施工作业）方式微粒运移出砂无机垢沉积有机垢沉积乳化堵塞相对渗透率效应固相侵入润湿性反转酸反应二次沉淀细菌与地层流体不配伍与岩石矿物不配伍储层损害诊断方法MethodsforRecognitionofFormationDamage储层物性条件差—饱和度、孔隙度、渗透率、裂缝存在储层损害作业因素,如完井作业中：—射孔参数不合理（孔眼密度低、孔眼太小，深度不够，打开不完善）—水泥环质量差、强度不高等低产原因损害可能存在的标志压力与产量关系变化波动很大产量低于经济下限产量要比中途测试、岩心分析、测井计算所预测值低得多同一油气藏，储层物性完全相同，但产量差异很大生产井出砂测试时出现表皮效应有机结垢和无机垢沉积注入能力急剧下降，措施或处理周期短诊断技术DST测试分析测井分析生产史分析相邻井产量对比压力不稳定试井分析生产效率剖面生产测井岩心实验分析井下照相井下取样分析节点分析提纲0、损害机理及诊断概述1、DST测试2、测井分析3、井史分析4、相邻井生产动态对比5、压力不稳定试井分析6、节点系统分析7、生产效率剖面8、生产测井9、岩心分析1、钻柱测试（DrillStemTests）Intheearlystagesofexploratorydrillingintoanewformation,DrillStemTestingisnormallyusedtoconfirmtheproductionpotentialofahydrocarbonshowHowever,ifgeochemicalanalysisofdrillchipsandcuttingsestablishesthepresenceofhydrocarbons,butDSTshowsthetestedintervaltobenon-productive,thenformationdamagepossiblyexistsAnalysisofthepressureversustimedatageneratedduringDSTcanbeusedsemi-quantitativelytodeterminetheseverityofdamagebycalculatingtheskin.Itis,however,desirabletoexercisecautionduringinitialDST,sincepressuresurgesandhighdrawdowncaninitiatefinesmovement.Reviewofprioroperationalhistoryisthennecessarytoestablishwhichaspectofthedrillingprocessmayhavegivenrisetodamage.–ThefollowingfigureshowsatypicalDSToutputillustratingahighpermeabilitydamagedzone.Noticethefollowingfeaturesthatarecharacteristicofdamage:ShortradiuscurvealongCDE*AnalmostflatslopealongDEAsharpriseafterclosed-inperiodasalongEFAhighdifferentialpressurebetweenaclosed-inandfinalflowpressure(EG)DSTTraceShowingExtremeDamageinaHighProductivityZonept坐封开井关井开井关井开封ExerciseinClass1。指出下列测试卡片曲线中，A、B两口井是否存在损害，并说明理由。2。油田开发中哪些作业可以增加渗透率pt曲线A曲线B•测井曲线上的泥浆侵入响应MudInvasionEffectsonWellLogs2、测井分析中子孔隙度降低感应电阻率降低Thedegreeanddepthoffiltrateinvasionduringdrillingcanbeestimatedfromdeep,mediumandshallowresistivitydevices(e.gLaterolog)orconductivitydevicessuchasdualinductionlogsorcombinationsthereof(e.gInduction-Laterolog).Thesedeviceswillgivesemi-quantitativeindicationsofpossibledamageduringproduction.AnalyticalmodelspresentedbyHassenfordescribingfiltrateinvasioncanalsobeusedtoestimatethedepthofinvasionparticularlyincaseswherethedepthofinvestigationoftheloggingtoolislimited.滤液侵入程度和深度可以从深、中、浅电阻率测井或双感应测井曲线进行半定量评价Figures5-3Aand5-3Bshowtypicalresistivityprofilesinflushed,transitionanduninvadedzonesforawaterandoilbearingzones,respectively.Inbothfigures,theresistivityofthemudflushedzones,Rxc)wasgreaterthantheresistivityoftheuninvadedzone,RE.CombinationoftheDualInductionLogandtheLaterologareusuallysufficientinmostcasestoindicatethedepthoffiltrateinvasion.Thetablebelowshowsthedifferentcombinationloggingdevicesforvariousdepthsofinvasion,whereRxoRE.Table5-1DepthofInvasionLoggingDeviceszeroorveryshallowinvasionRLLSRILMRILDREModerateinvasionRLLSRILMRILDREDeepinvasionRxoRLLSRILMRILDVerydeepinvasionRXORLLSRILMRILDFigure5-3Cillustratesaninvadedzoneatadepthof3700feetwherethereisaseparationbetweenthe16normaland64normal.NotethatR16”-R64”.Evaluationofthecaliperlogcangiverelativeindicationsofpermeabilityandprobableinvasionprofiles.IfproblemsareidentifiedbyDSTandlogs,furtherinvestigationisstillnecessarytopinpointwhataspectofthedrilling/completionprogramisresponsiblefortheapparentpoorformationresponse作业史分析Dailydrilling/cementing/completionreports,mudandcompletion,workoverandwellstimulationfluidprogramsshouldbereviewed(Allen).滤失量、pH值、钻速随深度变化Fluidloss,pHandROPdatashouldbeplottedasfunctionofdepthtohelpidentifyanyzoneswherehighpH-filtratelosshadoccurred.Suchzonesaregoodcandidatesfordamage.–Anindividualwellanalysisthenquantifieswhetherornotthewellisproducingtopotential.Ifnot,why?Andtheproductionpotentialbehindpipe.3、井史分析（WellHistoryReview）Theproductionpotentialofanidealwellinafield,poolorleaseisevaluated,whilerecognizingthatthewellpotentialwilldependonthefollowingfactors:–Typeofdrivemechanism–Statusofdepletion–Rockandfluidproperties(Kh,qh,1L,Krel,PVT,etc.)Theproductivityindex(PI)istypicallycomputedforunboundedandboundedreservoirsfromDarcy'sLawforSteadyStateIncompressibleFlowasfollows:Comparisonoftheoreticaltoactualproductionratescanbeusedtoestablishwhetherornotthewellisproducingatexptectedcapacity,forthegivenoperatingdrivemechanismasshownonFigure5-4AandB.ActualvsTheoreticalSpecifiedProductivityIndicesProductionHistoryShowingWellDamageProblem提纲0、损害机理及诊断概述1、DST测试2、测井分析3、井史分析4、相邻井生产动态对比5、压力不稳定试井分析6、节点系统分析7、生产效率剖面8、生产测井9、岩心分析Whenawellexperiencesanabnormalgraduald