天然能量开发阶段的缝洞型油藏井间连通性分析

Inter-well connectivity analysis in carbonate fracture-vuggy reservoir in natural energy development stage

研究碳酸盐岩缝洞型油藏天然能量开发阶段的采油井间连通关系对于后续实施注水开发、确定注采对应关系和转注油井以及进行注水井位部署都具有重要意义.由于静态法在矿场井间连通性分析中存在不确定性,所以通常采用动态连通性分析井间连通情况.本研究从生产动态数据入手,优选油压、流压、产能和动液面4类动态数据,首先基于动态时间规整算法,设计井间连通识别方法进行采油井间连通分析;其次以采油井间的动态曲线相似度为基础,采用“五标度改进层次分析-熵权法”计算各动态曲线相似度的指标权重;最后建立天然能量开发阶段缝洞型油藏的采油井间连通程度评价模型.利用该模型对某缝洞油藏进行实例分析,其评价结果与已知的静态连通分析结果及生产动态特征一致性高,验证了评价模型的准确性.该模型可以为天然能量开发阶段的缝洞型油藏采油井连通性分析提供参考.

It is of great importance to study the inter-well connectivity in the carbonate fracture-vuggy reservoirs during the stage of natural energy development,for the subsequent implementation water-flooding development,injection wells deployment,corresponding injection-production wells relationship characterization,and the choice of production wells transfer injection wells.In view of the uncertainty of static geological analysis,the dynamic analysis method is usually more preferred to study the inter-well connectivity.In this work,four types of dynamic data are selected for analysis,including tubing pressure,formation flowing pressure,oil capacity and working fluid level.An inter-well connectivity recognition method is then designed in use of dynamic time warping(DTW)algorithm to analyze production wells connectivity.The five-scale IAHP and entropy method is also used to calculate the index weight based on the dynamic curve similarities of production wells.Followed by,production well connectivity evaluation model is established for carbonate fracture-vuggy reservoir in the natural energy development stage.A fracture-vuggy reservoir example is analyzed,and the result shows an excellent matching with the existing results of static geological connectivity and production dynamic characteristics,which verifies the accuracy of the evaluation model.This model provides valuable insight on the production wells connectivity in carbonate fracture-vuggy reservoirs.