萨南东部过渡带300米地区精细地质描述及剩余油分布研究
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摘要
萨南东部300米地区油层属于松辽盆地白垩系地层中部含油气组合。为挖掘其高含水开发后期潜力，对其进行精细地质解剖，研究剩余油分布状况，为动态分析和调整挖潜奠定基础。
首先，利用测井曲线的自然可分性，寻找相对稳定的旋回界限划分单元，识别出四大类、10种微相及模型，并进行精细地质描述。
一是分流平原相砂体：1、曲流河砂体微相，代表大型低弯度的曲流河沉积，河道砂体规模很大；2、高弯曲分流砂体微相，砂体规模较大，分流河道砂体是侧向加积产物；3、低弯曲分流砂体微相，砂体规模较小，总体来看砂体连续性好，有废弃河道存在。
二是内前缘相砂体：1、枝状三角洲砂体微相，形成于水体较浅时期，是陆上的分流河道向水下前缘相的自然延续形成的；2、过渡状三角洲砂体微相，形成于河流作用减弱而湖浪改造作用增强时期，有明显反向性；3、坨状三角洲砂体微相，形成时波浪作用很强，水下分流河道连续性较差，呈坨状分布。
三是外前缘相砂体：1、主体带发育的稳定型砂体微相，以稳定分布的主体席状砂为主，几乎没有尖灭区；2、过渡状分布的砂体微相，砂体面积较大，有一定的条带方向性；3、不稳定分布的砂体微相，砂体主要分布于外前缘相的外缘，很不稳定，尖灭区占40%以上。
四、前三角洲尖灭区，主要为大面积的尖灭区，散布着零星的表外储层。
其次，在以上精细地质解剖及借鉴前人研究剩余油取得的成果，运用动静态资料相结合，逐井逐层落实水淹状况，综合评价、总结出5种剩余油宏观类型。一是井网控制不住型，主要是因原井网钻遇但未射孔，或是原井网未钻遇而加密井网钻遇形成的剩余油；二是注采不完善型，是由于原井网未射孔，在平面上造成注采不完善而形成的剩余油；三是层间干扰型，存在于纵向上和平
面上物性相对较差的油层中，由于层间干扰造成的不吸水、不出油而形成的剩
余油；四是层内未水淹型，存在于厚油层中，因层内的非均质性，导致底部水淹严重，如果层内有稳定的物性夹层，其顶部形成剩余油；五是成片分布差油层型，因油层薄而导致动用差或未动用，由此形成剩余油。
最后，运用精细解剖成果指导开发，取得了很好的开发效果。
The oil formation which is located 300 meters away from the east of Sanan area belongs to the combination of hydrocarbon bearing in the middle of Cretaceous formation at Songliao basin.
In order to tap its potential at the later stage of high water-cut, we analyze its detail geology, study the remaining oil distribution, thus lay foundation for dynamic analysis and adjustment.
Firstly, we make use of the natural divisibility of logging curves to find relatively stable cyclic boundary dividing unit, identify four major categories and ten kinds of micro-facies and models, and a detail geological description was given.
1. Distributary plain facies sands body: 1).Meandering sands micro-facies, which represents large low sinuosity meandering disposition, and the channel sands is very large. 2).High sinuosity distributary sands micro-facies, whose sands body is relatively large, and the distributary channel sands body is the product of laterally aggradational deposit. 3).Low sinuosity distributary sands micro-facies , whose sands body is relatively small, and on a gross sense the continuity of sands is good and there exists abandoned channel.
2. Inner front facies sands: 1).dendritic deltaic sands micro-facies, which formed by natural extent from land distributary channel to marine front facies at the shallow water stage. 2).Transitional type deltaic sands micro-facies, which formed at the stage when fluvial action weakens and wave action strengthens, have apparent reverse directionality. 3). Cuspate deltaic sands micro-facies, which formed at the time of powerful wave action, the continuity of marine distributary channel is bad, and distributes in cuspate shape.
3. Outer front facies sands: 1).Stable sands micro-facies developed by main belt, which mainly consists of main shelf blanket sands with stable distribution, and almost no pinchout area. 2).Sands micro-facies with transitional distribution, which sands area is large, and have certain belt directionality. 3).Sands micro-facies with unstable distribution, whose sands mainly distribute at the outer boundary of outer front facies, is not stable, and pinchout area accounts for more than 40%.
4. Front deltaic pinchout area, which mainly consists of large pinchout area, and disperses sporadic surface reservoir.
Secondly, based on the above detail geologic analysis and former remaining oil research results, combining with dynamic and static information, understand water out behavior by each formation and each, we evaluated and summarized five kinds of remaining oil microscopic types. The first one is uncontrollable well pattern type, which is resulted from the original well pattern being drilled but not perforated, or the original well pattern not being drilled but infill well pattern drilled. the second one is injection-production imperfection type, which is resulted from the original well pattern not being perforated and led to imperfection injection-production on the plane. The third one is interlayer plane interference type, which exists in the oil formation with relatively bad petrophysical property at the longitudinal and planar directions, and resulted from non water absorption and oil production led by interlayer and plane interference. The fourth one is inner layer non-water-flooded type, which exists in thick oil formation. Inner formation heterogeneity leads to serious water out at the bottom. If there is stable petrophysical interbed in the formation, it will form remaining oil at the top. The fifth one is bad oil formation with sheet distribution, which is formed by bad production or non-production because of thin oil formation.
Finally, we get a better production effect by using accurate geologic analysis results.
首先，利用测井曲线的自然可分性，寻找相对稳定的旋回界限划分单元，识别出四大类、10种微相及模型，并进行精细地质描述。
一是分流平原相砂体：1、曲流河砂体微相，代表大型低弯度的曲流河沉积，河道砂体规模很大；2、高弯曲分流砂体微相，砂体规模较大，分流河道砂体是侧向加积产物；3、低弯曲分流砂体微相，砂体规模较小，总体来看砂体连续性好，有废弃河道存在。
二是内前缘相砂体：1、枝状三角洲砂体微相，形成于水体较浅时期，是陆上的分流河道向水下前缘相的自然延续形成的；2、过渡状三角洲砂体微相，形成于河流作用减弱而湖浪改造作用增强时期，有明显反向性；3、坨状三角洲砂体微相，形成时波浪作用很强，水下分流河道连续性较差，呈坨状分布。
三是外前缘相砂体：1、主体带发育的稳定型砂体微相，以稳定分布的主体席状砂为主，几乎没有尖灭区；2、过渡状分布的砂体微相，砂体面积较大，有一定的条带方向性；3、不稳定分布的砂体微相，砂体主要分布于外前缘相的外缘，很不稳定，尖灭区占40%以上。
四、前三角洲尖灭区，主要为大面积的尖灭区，散布着零星的表外储层。
其次，在以上精细地质解剖及借鉴前人研究剩余油取得的成果，运用动静态资料相结合，逐井逐层落实水淹状况，综合评价、总结出5种剩余油宏观类型。一是井网控制不住型，主要是因原井网钻遇但未射孔，或是原井网未钻遇而加密井网钻遇形成的剩余油；二是注采不完善型，是由于原井网未射孔，在平面上造成注采不完善而形成的剩余油；三是层间干扰型，存在于纵向上和平
面上物性相对较差的油层中，由于层间干扰造成的不吸水、不出油而形成的剩
余油；四是层内未水淹型，存在于厚油层中，因层内的非均质性，导致底部水淹严重，如果层内有稳定的物性夹层，其顶部形成剩余油；五是成片分布差油层型，因油层薄而导致动用差或未动用，由此形成剩余油。
最后，运用精细解剖成果指导开发，取得了很好的开发效果。
The oil formation which is located 300 meters away from the east of Sanan area belongs to the combination of hydrocarbon bearing in the middle of Cretaceous formation at Songliao basin.
In order to tap its potential at the later stage of high water-cut, we analyze its detail geology, study the remaining oil distribution, thus lay foundation for dynamic analysis and adjustment.
Firstly, we make use of the natural divisibility of logging curves to find relatively stable cyclic boundary dividing unit, identify four major categories and ten kinds of micro-facies and models, and a detail geological description was given.
1. Distributary plain facies sands body: 1).Meandering sands micro-facies, which represents large low sinuosity meandering disposition, and the channel sands is very large. 2).High sinuosity distributary sands micro-facies, whose sands body is relatively large, and the distributary channel sands body is the product of laterally aggradational deposit. 3).Low sinuosity distributary sands micro-facies , whose sands body is relatively small, and on a gross sense the continuity of sands is good and there exists abandoned channel.
2. Inner front facies sands: 1).dendritic deltaic sands micro-facies, which formed by natural extent from land distributary channel to marine front facies at the shallow water stage. 2).Transitional type deltaic sands micro-facies, which formed at the stage when fluvial action weakens and wave action strengthens, have apparent reverse directionality. 3). Cuspate deltaic sands micro-facies, which formed at the time of powerful wave action, the continuity of marine distributary channel is bad, and distributes in cuspate shape.
3. Outer front facies sands: 1).Stable sands micro-facies developed by main belt, which mainly consists of main shelf blanket sands with stable distribution, and almost no pinchout area. 2).Sands micro-facies with transitional distribution, which sands area is large, and have certain belt directionality. 3).Sands micro-facies with unstable distribution, whose sands mainly distribute at the outer boundary of outer front facies, is not stable, and pinchout area accounts for more than 40%.
4. Front deltaic pinchout area, which mainly consists of large pinchout area, and disperses sporadic surface reservoir.
Secondly, based on the above detail geologic analysis and former remaining oil research results, combining with dynamic and static information, understand water out behavior by each formation and each, we evaluated and summarized five kinds of remaining oil microscopic types. The first one is uncontrollable well pattern type, which is resulted from the original well pattern being drilled but not perforated, or the original well pattern not being drilled but infill well pattern drilled. the second one is injection-production imperfection type, which is resulted from the original well pattern not being perforated and led to imperfection injection-production on the plane. The third one is interlayer plane interference type, which exists in the oil formation with relatively bad petrophysical property at the longitudinal and planar directions, and resulted from non water absorption and oil production led by interlayer and plane interference. The fourth one is inner layer non-water-flooded type, which exists in thick oil formation. Inner formation heterogeneity leads to serious water out at the bottom. If there is stable petrophysical interbed in the formation, it will form remaining oil at the top. The fifth one is bad oil formation with sheet distribution, which is formed by bad production or non-production because of thin oil formation.
Finally, we get a better production effect by using accurate geologic analysis results.
引文
[1] 杨万里，松辽板内陆相沉积盆地石油地质规律的再认识，大庆石油管理局，1984年
[2] 任继顺，中国大地构造及其演化，地质出版社，1981年
[3] 隋军、赵翰卿等，大庆油田河流——三角洲相储层研究，石油工业出版社，2000年
[4] 朱筱敏，层序地层学原理及应用，石油工业出版社，1998年
[5] 裘亦楠、薛叔浩等，油气储层评价技术，石油工业出版社，1997年
[6] 李兴国，陆相储层沉积微相与微型构造，石油工业出版社，2000年
[7] 裘亦楠，开发地质方法论（一），石油勘探与开发，1996年，23（2），43-47
[8] 金毓荪、巢华庆等，采油地质工程，石油工业出版社，2003年
[9] 王坤、靳兴等，三次加密剩余油综合描述技术，大庆石油地质与开发，2003年，22（2），35
[10] 王志章、蔡毅、杨蕾，开发中后期油藏参数变化规律及变化机理，石油工业出版社，1998年
[11] 叶庆全、冀宝发等，油气田开发地质，石油工业出版社，1999年
[12] 张吉、张烈辉等，陆相碎屑储层隔夹层成因、特征及其识别，大庆石油地质与开发，2003年，22（4），1
[2] 任继顺，中国大地构造及其演化，地质出版社，1981年
[3] 隋军、赵翰卿等，大庆油田河流——三角洲相储层研究，石油工业出版社，2000年
[4] 朱筱敏，层序地层学原理及应用，石油工业出版社，1998年
[5] 裘亦楠、薛叔浩等，油气储层评价技术，石油工业出版社，1997年
[6] 李兴国，陆相储层沉积微相与微型构造，石油工业出版社，2000年
[7] 裘亦楠，开发地质方法论（一），石油勘探与开发，1996年，23（2），43-47
[8] 金毓荪、巢华庆等，采油地质工程，石油工业出版社，2003年
[9] 王坤、靳兴等，三次加密剩余油综合描述技术，大庆石油地质与开发，2003年，22（2），35
[10] 王志章、蔡毅、杨蕾，开发中后期油藏参数变化规律及变化机理，石油工业出版社，1998年
[11] 叶庆全、冀宝发等，油气田开发地质，石油工业出版社，1999年
[12] 张吉、张烈辉等，陆相碎屑储层隔夹层成因、特征及其识别，大庆石油地质与开发，2003年，22（4），1