鄂尔多斯盆地马岭油田长8_1储层不同成岩相类型可动流体赋存特征分析  

Occurrence Characteristics of Movable Fluids in Different Diagenetic Facies of the Chang 8_1 Reservoir,Maling Oilfield,Ordos Basin

作　　者：黎盼 孙卫[1] 高永利[2] 折文旭 杜堃 LI Pan;SUN Wei;GAO Yongli;SHE Wenxu;DU Kun(State Key Laboratory for Continental Dynamics and Department of Geology,Northwest University,Xi'an,Shaanxi 710069;College of Petroleum Engineering,Xi'an Shiyou University,Xi'an,Shaanxi 710065)

机构地区：[1]西北大学地质学系/大陆动力学国家重点实验室,陕西西安710069 [2]西安石油大学石油工程学院,陕西西安710065

出　　处：《地质与勘探》2019年第2期649-660,共12页Geology and Exploration

基　　金：国家科技重大专项大型油气田及煤层气开发(编号:2011ZX05044);陕西省青年人才基金(编号:No.2016JQ4022)联合资助

摘　　要：针对鄂尔多斯盆地马岭油田长8_1储层微观非均质性强、微观孔隙结构复杂、流体分布特征差异性明显等问题,利用核磁共振技术对不同成岩相类型储层可动流体进行定量评价,辅助以常规物性、图像孔隙、铸体薄片、扫描电镜、高压压汞和恒速压汞等微观实验,分析不同类型的成岩相可动流体赋存特征差异性及其主控因素。研究结果表明,研究区主要分成四种成岩相,分别为绿泥石+伊利石胶结-粒间孔相、伊利石+高岭石胶结-粒间孔+溶蚀相、绿泥石+伊利石胶结-溶蚀相和碳酸盐胶结致密相。四种不同成岩相类型的微观孔隙结构有着明显的差异,微观孔隙结构差异是造成可动流体饱和度差异的主要因素。不同成岩相类型的储层渗透率与可动流体参数的相关性较强,储层物性越好,可动流体参数变化幅度越大;孔喉半径大小、孔喉半径比、分选系数、孔喉进汞饱和度以及粘土矿物的充填是影响不同成岩相类型可动流体赋存特征差异的主控因素。其中有效喉道半径、孔喉进汞饱和度、孔喉半径比是影响可动流体饱和度的主要因素,分选系数对可动流体饱和度影响较明显,储层物性对可动流体饱和度的影响较小。The exploration of the Chang 81 reservoir in Maling Oilfield,Ordos Basin,has been challenged by strong heterogeneity,complicated microscopic pore structures,low saturation of movable fluids,and different fluid distribution characteristics. To solve this problem,this study used nuclear magnetic resonance( NMR) technique to quantitatively evaluate the movable fluids in the reservoir with different diagenetic facies types. Moreover,microscopic experiments were conducted to analyze the occurrence characteristics and influential factors of movable fluids in different diagenetic facies types,including conventional physical property analysis,image porosity measurement,casting thin section observation,SEM analysis,high pressure mercury intrusion tests,and rate-controlled mercury intrusion tests. The results show that four types of diagenetic facies could be divided in the area,namely chlorite + illite cementation-intergranular pore facies,illite + kaolinite cementation-intergranular pore + solution facies,chlorite + illite cementation-solution facies and carbonate cementation dense facies. There are obvious differences in the micro-pore structure of these four types of diagenetic facies and micro-pore structure is the main factor that causes the difference of the saturation of movable fluid. Reservoir permeability is well correlated with movable fluid saturation.Generally,better physical properties lead to larger variation of movable fluid saturation. The pore throat radius,pore-throat radius ratio,sorting coefficient,maximum mercury saturation in pores and throats,and interstitial clay minerals are the main factors that influence the occurrence characteristics in different diagenetic facies. Among them,the effective pore throat radius,maximum mercury saturation and pore-throat radius ratio are the dominant factors;the sorting coefficient has a certain influence;and physical properties can pose a little effect on the movable fluid saturation.

关 键 词：马岭油田 长81储层 不同成岩相 微观孔隙结构 可动流体 鄂尔多斯盆地 

分 类 号：TE122.23[石油与天然气工程—油气勘探]