基于三维激光扫描的露头天然裂缝识别与发育模式

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中图分类号：TE122.2 文献标志码：A

Abstract：Naturalfracturesarekeyfactors inimprovingthequalityoflow-porosityreservoirsandenhancingpetroleumproductivity.Establishingnaturalfracturedevelopmentmodelsinanalogousoutcrops isaneffectivemethodtoguidethepredictionofsubfacefracturedistribution.UsingtheKuqa forelandbasinasanexample，anatural fracturedevelopment modelof anticlinalstructures was establishedbyapplying 3Dlaserscanning technologytoidentifynatural fractures，supplemented by manualmeasurementsandgeologicaldatafromtypical petroleumreservoirs.Theevolutionprocessof naturalfractures wasalsoanalyzed.TheresultsshowthatnaturalfracturesinanticlinalstructuresoftheKuqaforelandbasinaremainlyhigh-angle， andcanbeclassifiedintotwostages（pre-foldandsyn-fold）andfivetypes.Pre-foldfracturesarefewinnumberandmostly ineffective，thus makingonlyalimitedcontributiontopetroleumacumulationinthebasin.Bycontrast，syn-foldfracturesabundantandhighlyefective，servingaseficientseepagechanelsforpetroleummigrationand formingessentialgeological conditionsforfracturedpetroleumreservoirsintheKuqa forelandbasin.Althoughthedensityofnaturalfracturesintheanticlinecoresislowerthan thatinthewings，thefractureaperture，permeability，andpetroleumproductivityare higher，consistent with explorationresults from typicalanticlinalpetroleumreservoirs.Considering thecurrent limitationsof3Dlaser scanning，suchastheneedtoimprovefracturerecognitionratesandthedificultyinidentifying parameterslikefractureper tureandfillingcoeficient，itremainsnecessarytodevelopfeasiblemethodstofurtheroptimizeandrefinethe technology.

Keywords：3D laser scanning；natural fracture;development model；Kuqa foreland basin

天然裂缝是改善含油气盆地低孔致密储层质量、提高油气产能的重要因素，特别是在中国中西部塔里木盆地北缘、准噶尔盆地南缘、四川盆地西北缘等大型叠合前陆盆地的低孔致密碎屑岩储层中，天然裂缝的发育往往是油气高产的必要条件[1-6]。（剩余20502字）