马岭油田中一区储层流动单元研究

Study of reservoir flow units of Zhong1 block in Maling oilfield

（1.西北大学地质学系,陕西西安710069; 2.西安石油大学油气资源学院，陕西西安710065）

Department of geology，Northwest University，Xi-an 710069, China

:储层流动单元指的是连通体内具有相似岩性和物性特征的储集单元，而储层的非均质性则表现为不同流动单元之间岩性和物性的差异性。因此，利用表征储层岩性和物性特征的流动层带指标、孔隙度、渗透率和泥质含量等参数对储层流动单元进行定量评价，可以更好地了解地下油水运动规律以及油田注水开发过程中剩余油的分布。在马岭油田中一区开展了储层流动单元的划分和剩余油分布的研究。首先选择马岭油田中一区的4口井作为关键井，利用4口关键井的岩心分析资料和测井资料，计算和提取了流动层带指标和孔隙度、渗透率、泥质含量等参数，进行了聚类分析，并参照油田实际开发情况，确定了该区主力油层延安组储层流动单元的划分标准，即将延安组储层流动单元定义为4类，Ⅰ类的储集性能最好，Ⅳ类的储集性能最差。然后，采用神经网络技术，根据延安组储层流动单元的划分标准，对延安组的延2+39、延110、延210、延310和延410等5个油层组进行了储层流动单元平面分布预测，并结合实际地质和生产状况，对各类流动单元的主要特征进行了分析，研究了流动单元与储层吸水、产液和剩余油分布之间的关系。研究结果表明，Ⅰ类和Ⅱ类流动单元区储集性能好，虽然开发程度高，但仍然是油田目前剩余油分布的主要区域，是油田挖潜的主要目标。

Reservoir flow units are the accumulating units having similar lithology and physical property within the connected bodies. While reservoir heterogeneity show the contrast of lithology and physical property between different reservoir flow units. So, the reservoir flow units can be quantitatively evaluated by some parameters such as flowing zone indexes, porosity, permeability, and shale content, etc. The study of reservoir flow units can better understand the flowing rule of underground oil and water and the distribution of residual oil. In Zhong1 block, the classification of reservoir flow units and the study of residual oil distribution were carried out. First, we selected 4 wells as the key wells and used the core analysis data and logging data to calculate and extract the flow zone indexes, porosity, permeability, and shale content, etc. In addition, we also made the cluster analysis. Taking the actual development situation as reference, we proposed the classification criteria of reservoir flow units in Yan-an formation (the main layer) and divided these reservoir flow units into 4 types based on the criteria. The accumulating ability of type Ⅰis the best and that of type Ⅳ is the worst. Then, according to the criteria, we used the neural network to predict the surface distribution of reservoir flow units in formations of Yan2+39, Yan110, Yan210, Yan310, and Yan410. The essential features of each type of flow units were analyzed according to the actual geological and production situation. The relationship of the flow units with the water absorption property, the produced fluid, and the residual oil distribution of the reservoir was studied. The results show that the accumulating ability in the zones of type Ⅰand Ⅱare still very good. Although the development degree in these areas is quite high, they are still the main distribution areas of residual oil and the targets of potential-probing in the oilfield.