苏里格苏25区块井位部署方法与应用

Method and application of well disposition in Su 25 block

为了降低苏里格气藏苏25区块新井建产地质风险,提升区域Ⅰ+Ⅱ类井钻井比例,针对该区气藏"低孔隙度、低渗透率、低地层压力、低含气丰度、含气砂体厚度和分布变化大"的特点,需要开展井位优化部署方法研究。在系统整理试气资料的基础上,分析累计产量与无阻流量、套管压力、油管压力、静止压力、流动压力等参数之间的关系发现,求产初期地层流压与平均年产量具有较好的相关性,在原有区域井位优选方法的基础上,结合井底流压与单井平均年产量的相关关系,把求产初期地层流压与换算好的单井平均年产量分别绘制成等值线图并进行叠合,提出了区域"流压——平均年产量"井位部署方法。经过实际应用,该方法实施效果良好,Ⅰ+Ⅱ类井钻井比例明显增加,提高了单井控制储量和气田的采收率。

In order to reduce the geologic risk of new well construction in Su 25 block of Sulige gas reservoir and increase the drilling proportion of wells of the types ofⅠandⅡin the area,in view of the characteristics of low porosity,low permeability,low formation pressure,low gas abundance,great variation in thickness and distribution of gas-bearing sand bodies in this area,study on the method of well optimized disposition should be conducted.On the basis of systematical collation of gas production test data,by analyzing the relationship between cumulative production and parameters such as open flow potential,casing pressure,tubing pressure,static pressure and flowing pressure,it is found that there is a good correlation between formation flowing pressure and average annual output at the initial stage of production.On the basis of the original well location optimization method in this area and the correlation between the bottomhole producing pressure and average annual output of a single well,the formation flowing pressure at the initial stage of production and the converted average annual production of a single well were plotted into contour maps and superimposed respectively.A method of regional well disposition with flowing pressure and average annual output was proposed.The practical application shows that the method has a good effect.The drilling proportion of the wells of the types ofⅠandⅡhas increased markedly.The controlled reserves of single well and the recovery efficiency of gas field are improved.