微地震监测技术在地下储气库中的应用  

Application of microseismic monitoring technology in underground gas storage

作　　者：魏路路 井岗 徐刚[1] 王飞 李晓峰 刘博[1] Wei Lulu;Jing Gang;Xu Gang;Wang Fei;Li Xiaofeng;Liu Box(CNPC Bureau of Geophysical Prospecting INC.,Zhuozhou,Hebei 072750,China;PetroChina West-East Gas Pipeline Company,Zhenjiang,Jiangsu 212000,China)

机构地区：[1]中国石油集团东方地球物理勘探有限责任公司 [2]中国石油西气东输管道公司

出　　处：《天然气工业》2018年第8期41-46,共6页Natural Gas Industry

基　　金：国家科技重大专项"油藏及非常规气藏地球物理配套技术"(编号:2017ZX05018-004)

摘　　要：为了保证地下储气库(以下简称储气库)在建设和运行过程中的完整性与安全性,必须建立完善的监测系统。为了给储气库的安全运行提供参考,在分析微地震监测技术主要方法——纵横波时差定位算法和b值法原理的基础上,以中国东部某盐穴储气库为例,利用微地震监测技术对该储气库造腔和注气过程进行监测,采用纵横波时差定位算法对微地震事件位置进行反演,并根据造腔井附近的微地震事件定位结果对腔体形态进行刻画,同时对微地震事件进行b值法分析,判断注气过程中是否诱发断层活动。研究结果表明:(1)该盐穴储气库在造腔井中未发现能量较大的破裂或垮塌,造腔工艺较安全;(2)造腔井腔体形态不规则,可近似为圆柱体;(3)注气井注气压力上升可导致断层活动,但诱发断层活动是否对储气库完整性造成危害则需要对该区域进行长期监测和分析研究才能做出判定。结论认为:(1)为了保障储气库的安全运行,应降低断层附近注气井的上限压力;(2)微地震监测技术在保障储气库安全运行中起着至关重要的作用,应在储气库建设和运行过程中加强实时监测,以期为储气库安全预警和优化运行提供科学依据。In order to ensure the integrity and safety of underground gas storage（UGS） during its building and running,it is necessary to establish a complete monitoring system.In this paper,the principles of main microseismic monitoring technologies（i.e.,P–S wave location algorithm and b-value method） were firstly analyzed.Then,one salt cavern UGS in eastern China was taken as an example.Its solution mining and gas injection process was monitored using microseismic monitoring technologies,and the locations of microseismic events were inverted by means of P–S wave location algorithm.Furthermore,the morphology of the cavity was depicted according to the location results of microseismic events near the cavity-building well.In addition,the microseismic events were analyzed using b-value method to determine whether a faulting activity is induced in gas injection,so as to provide reference for the safe operation of UGS.And the following research results were obtained.First,no large fracture or collapse was discovered in the cavity-building well of this salt cavern UGS.And it is indicated that the solution mining process is safe.Second,the shape of the cavity is irregular and it can be approximated as a cylinder.Third,the increase of gas injection pressure of gas injecting well can induce a faulting activity,but whether the induced faulting activity has damage to the UGS integrity cannot be judged unless long-term monitoring and analysis are carried out in this area.In conclusion,the upper limit pressure of the gas injecting wells near the fault shall be reduced in order to ensure the safe operation of UGS.In addition,microseismic monitoring technology plays a vital role in guaranteeing the safe operation of UGS,so it is necessary to strengthen the real-time UGS monitoring during its building and running so as to provide a scientific basis for its early safety warning and operation optimization.

关 键 词：地下储气库 微地震监测 纵横波时差定位算法 b值法 造腔形态 注气 诱发断层活动 盐穴储气库 

分 类 号：TE972.2[石油与天然气工程—石油机械设备]