致密油大规模多段压裂水平试井解释及外区渗透率对试井曲线的影响

发布时间：2019-05-15 18:12

【摘要】：多段压裂水平井试井解释能对压裂规模、主裂缝半长等参数进行有效评价,为产能评价等提供基础参数.然而当前缺少针对实际井例数据进行的深入分析.基于PEBI(perpendicular bisector)网格对油水两相渗流方程进行数值求解,利用无限导流的主裂缝与分支缝导致的区域渗透率扩大来描述SRV(stimulated reservoir volume),建立了致密油大规模多段压裂水平井瞬态压力分析方法.基于大庆油田的实测数据进行解释并进行渗透率敏感性分析,研究了复合区域下的参数调整方法.研究表明,当外区渗透率变小时,早期的压力导数变小,后期的压力导数变大,而不是所有的压力导数值都变大.压力导数由小到大的转折点时间与渗透率大小相关.因而,当前期的压力导数曲线拟合效果好、后期的压力导数拟合效果差时,不能仅通过调整外区的渗透率来拟合,还应调整其他参数.另外,大庆致密油藏多段压裂水平井实测曲线中的启动压力梯度特征不明显.相关研究结果对致密油大规模多段压裂水平井实测数据解释具有重要的指导意义.
[Abstract]:The well test interpretation of multi-section fracturing horizontal well can effectively evaluate the parameters such as fracturing scale, half length of main fracture, etc., and provide the basic parameters for productivity evaluation. However, there is a lack of in-depth analysis of the actual well case data. Based on PEBI (perpendicular bisector) grid, the oil-water two-phase seepage equation is solved numerical, and the regional permeability expansion caused by the main fracture and branch fracture of infinite diversion is used to describe the SRV (stimulated reservoir volume),. A transient pressure analysis method for large-scale multi-stage fracturing horizontal wells with tight oil is established. Based on the measured data of Daqing Oilfield and permeability sensitivity analysis, the parameter adjustment method in composite area is studied. The results show that when the permeability of the outer region becomes smaller, the early pressure derivative becomes smaller and the later pressure derivative becomes larger, rather than all the pressure derivation values. The turning point time of pressure derivative from small to large is related to permeability. Therefore, when the fitting effect of the pressure derivative curve in the early stage is good and the fitting effect of the pressure derivative in the later stage is poor, it can not only be fitted by adjusting the permeability of the outer area, but also other parameters should be adjusted. In addition, the characteristics of start-up pressure gradient in the measured curve of multi-stage fracturing horizontal wells in Daqing tight reservoir are not obvious. The related research results have important guiding significance for the interpretation of measured data of large-scale multi-stage fracturing horizontal wells in tight oil.
【作者单位】：合肥工业大学数学学院;中国石油大庆油田测试技术服务分公司;中国科学技术大学工程科学学院;
【基金】：“十三五”国家重大科技专项(No.2017ZX05009005-002) 中石油-中科院战略合作项目(No.2015A-4812)
【分类号】：TE353

【相似文献】