CAJ | 학술논문

为了阐明渤海湾盆地东营凹陷北部陡坡带近岸水下扇低渗储层成因，应用岩心和储层分析资料，通过储层岩石特征、成岩作用、成岩序列和孔隙演化及其控制因素分析，指出东营凹陷北部沙河街组近岸水下扇砂体由长石砂岩、长石质岩屑砂岩等构成，储层经历了较强机械压实作用、碳酸盐胶结作用、碳酸盐和长石溶解作用等成岩作用，现储层埋深1700～3500 m，处于中成岩演化阶段，总体形成了中低孔低渗（孔隙度平均为11.3％，渗透率平均为23.12×10-3μm2）储层。储层中低孔低渗主要受控于较强的压实作用和较强的碳酸盐胶结作用，但溶蚀成岩作用对于改善储层质量起到了重要作用。主要在2900～3200 m深度段，有机酸对砂岩长石颗粒的溶蚀，形成的粒间和粒内孔隙不仅增加了孔隙度，而且提高了储层渗透率，改善了储层质量（孔隙度可达到25％，渗透率达到1000×10-3μm2）。显然，发现溶蚀作用及其形成的次生孔隙发育深度段对于预测有利储层是非常重要的。
위료천명발해만분지동영요함북부두파대근안수하선저삼저층성인，응용암심화저층분석자료，통과저층암석특정、성암작용、성암서렬화공극연화급기공제인소분석，지출동영요함북부사하가조근안수하선사체유장석사암、장석질암설사암등구성，저층경력료교강궤계압실작용、탄산염효결작용、탄산염화장석용해작용등성암작용，현저층매심1700～3500 m，처우중성암연화계단，총체형성료중저공저삼（공극도평균위11.3％，삼투솔평균위23.12×10-3μm2）저층。저층중저공저삼주요수공우교강적압실작용화교강적탄산염효결작용，단용식성암작용대우개선저층질량기도료중요작용。주요재2900～3200 m심도단，유궤산대사암장석과립적용식，형성적립간화립내공극불부증가료공극도，이차제고료저층삼투솔，개선료저층질량（공극도가체도25％，삼투솔체도1000×10-3μm2）。현연，발현용식작용급기형성적차생공극발육심도단대우예측유리저층시비상중요적。
In order to demonstrate the genesis of low permeability reservoir of nearshore subaqueous fan in northern steep slope of Dongying sag , abundant cores and reservoir analysis data were utilized to conduct the research on lithological characters of reservoir ,diagensis ,diagenetic sequence and porosity evolution as well as their controlling factors .The sand-bodies of nearshore subaqueous fan of the Shahejie Formation consist of arkose and feldspathic lithic sandstone and the reservoirs have experienced strong compaction ,carbonate cementation ,dissolution of calcite and feldspar in the burial dia-genetic evolution .The reservoirs are at the middle diagenetic stage now ,have a burial depth in the range of 1 700-3 500 m and mid-low porosity ( mean porosity 11.3%) and low permeability ( mean permeability 23.12 ×10 -3 μm2 ) .The strong compaction and carbonate cementation reduced the porosity and permeability of the reservois ,while dissolution contribu-ted to the improvement of reservoir quality .The intergranular pores and intragranular pores resulted from dissolution of calcite and feldspar at the depth of 2 900-3 200 m are constructive to reservoir quality ( porosity up to 25%and permea-bility up to 1 000 ×10 -3μm2 ) .Obviously ,identification of dissolution and intervals with well-developed secondary pores is extremely important for predicting favorable reservoir .