苏里格气田有效储层识别方法研究

Research on Effective Reservoir Identification Method of Sulige Gas field

苏里格气田储层砂体多以透镜状、条带状或纵横叠置等形态不稳定发育,储层物性、含气性差异显著,导致气测录井及测井响应特征复杂多变,给有效储层识别带来较大的困难和挑战。通过对已钻气测异常井层进行二次解释评价,从录井角度出发,结合试气产能情况,分析和总结不同含气储层全烃与烃组分值的响应特征,确定天然气评价敏感参数。发现烃类气体组成成分和含量与不同层系岩性及显示层有很好的相关关系,录测信息结合可以有效区分气层、差气层、气水同层、干层等。通过反复对比验证,优选全烃-孔隙度、全烃-声波时差、全烃-密度、全烃-伽马4个录测井参数结合图版作为评价选层的依据,并形成了相应的天然气评价标准。现场应用取得良好效果,2020年完成新钻63口井的解释评价任务,解释符合率达到95.5%,较往年提高一个百分点。

The reservoir sand bodies in Sulige gas field are developed in unstable forms such as lenticular,banded or vertical and horizontal superposition,and the reservoir physical properties and gas content are significantly different,resulting in complex and variable gas logging and logging response characteristics,which brings great difficulties and challenges to effective reservoir identification.Based on the secondary interpretation and evaluation of the drilled well with abnormal gas measurement,the response characteristics of total hydrocarbon and hydrocarbon group scores of different gas-bearing reservoirs are analyzed and summarized from the perspective of logging and combined with the gas test productivity,and the sensitive parameters of gas evaluation are determined.It is found that the composition and content of hydrocarbon gas are closely related to the lithology and display layers of different strata,and the combination of recorded and measured information can effectively distinguish the gas layer,poor gas layer,gas-water same layer,dry layer,etc.Through repeated comparison and verification,four logging parameters including total hydrocarbon-porosity,total hydrocarbon-acoustic time difference,total hydrocarbon-density,and total hydrocarbon-gamma were selected as the basis for evaluating and selecting layers,and the corresponding natural gas evaluation criteria were formed.In2020,63 new Wells were drilled,with an interpretation compliance rate of 95.5%,one percentage point higher than in previous years.