简介:Shales,themostabundantofsedimentaryrocks,arevaluedasthesource-rocksandsealstoporouspetroleumreservoirs.Overthepast-twentyyears,organic-richshaleshavealsoemergedasvaluablepetroleumsystems(reservoir,seal,andsourcerockscontainedinthesameformation).Assuchtheyhavebecomeprimarytargetsforpetroleumexplorationandexploitation.ThisPart1ofathree-partreviewaddressesthebulkproperties,multi-scalegeometryandgasadsorptioncharacteristicsofthesediverseandcomplexrocks.Shalesdisplayextremelylowpermeability,andtheirporosityisalsolow,butmulti-scale.Characterizingthegeometryandinterconnectivityofthepore-structureframeworkswiththenatural-fracturenetworkswithinshalesisessentialforestablishingtheirpetroleumexploitationpotential.Organic-richshalestypicallycontaintwodistincttypesofporosity:matrixporosityandfractureporosity.Inadditiontointer-granularporosity,thematrixporosityincludestwotypesofmineral-hostedporosity:inorganic-mineral-hostedporosity(IP);and,organic-matter-hosted(withinthekerogen)porosity(OP).Whereas,thefractureporosityandpermeabilityiscrucialforpetroleumproductionfromshales,itiswithintheOPwhere,typically,muchofthein-situoilandgasresourcesresides,andfromwhereitneedstobemobilized.OPincreasessignificantlyasshalesbecomemorethermallymature(i.e.,withinthegasgenerationzones),andplaysakeyroleintheultimaterecoveryfromshale-gassystems.Shales'methanesorptioncapacities(MSC)tendstobepositivelycorrelatedwiththeirtotalorganiccarboncontent(TOC),thermalmaturation,andmicroporevolume.Claymineralsalsosignificantlyinfluencekeyphysicalpropertiesofshalerelatedtofluidflow(permeability)andresponsetostress(fracability)thatdeterminetheirprospectivityforpetroleumexploitation.Claymineralscanalsoadsorbgas,somemuchbetterthanothers.Thesurfaceareaoftheporestructureofshalescanbepositively
简介:贵州省赤水地区下三叠统嘉陵江组的沉积相属于陆表海碳酸盐台地沉积,嘉二1—嘉一层段储层岩性主要为颗粒灰岩、粉晶白云岩。有利储层为裂缝-孔隙型,并具有低孔、低渗的特点,有利储产层的发育须要构造裂缝的连通。宝元构造为嘉二1~嘉一有利储层发育的最有利区,旺隆构造为嘉二1~嘉一有利储层发育的次有利区,太和构造为嘉二1~嘉一有利储层发育的差有利区。