针对东濮凹陷胡状集油田胡12块严重非均质油藏，采用室内实验对注水前后实际岩心样品进行对比分析，研究了注水开发过程中的流体动力地质作用.结果表明，酸性介质条件的化学动力作用加速了碎屑组分中的长石类矿物尤其是斜长石的溶蚀，同时生成了新的高岭石晶体并分布于细小孔喉，但对碳酸盐类矿物的影响较小.注水冲刷等物理动力地质作用造成了储集层泥质矿物总量的降低和粉砂—极细砂级石英颗粒的缺失，且主要发生在物性较好且优势渗流通道较发育的层段.在储集层孔喉变化方面，注水开发既使相对较大孔喉增加，改善了储集层的渗滤条件，也使孔喉分选程度降低，加剧了储集层微观非均质性.从储集层孔隙度、渗透率等宏观参数变化看，注水开发致使储集层总体平均有效孔隙度降低4.63%，而总体平均有效渗透率上升8.93%，原始物性不同的储集层注水后物性变化呈现出明显的“马太效应”.图7表3参15%Hu12 Block of the Huzhuangji Oilfield is a typical strongly heterogeneous reservoir. The hydrodynamic geology effect was studied by comparing experimental results of cores before and after waterflooding. The experimental results show that the chemical force of acidic medium accelerates the dissolution of plagioclase, generating new kaolinite crystals in small pore throats at the same time. The chemical force has less impact on carbonate minerals. The physical force of the injected water caused the reduction of the total content of argillaceous minerals and the loss of quartz grains of silt to very fine sizes, which occurred in layers with good physical properties and developed channeling paths. In terms of changes in pore-throats, waterflooding resulted in the increase of the large pore-throats and improvement of percolation conditions, also gives rise to the reduction of pore throat sorting and the aggravation of micro-heterogeneity of reservoir. With respect to variations in reservoir macroscopic parameters, waterflooding leads to the drop of overall average effective porosity by 4.63% and the rise of overall average effective permeability by 8.93%. The physical property changes of reservoirs of different original properties take on obvious“Matthew Effect”.
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