四川盆地简阳—三台火山岩气藏出砂原因分析及防砂措施探索  

Causes and control measures for sand production in volcanic gas reservoirs,Jianyang-Santai area,Sichuan Basin

作　　者：戴强 吴军 罗磊 邹波 DAI Qiang;WU Jun;LUO Lei;ZOU Bo(Drilling&Production Technology Research Institute,CNPC Chuanqing Drilling Engineering Company Limited,Chengdu,Sichuan 610052,China;Exploration Division,PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610041,China)

机构地区：[1]中国石油川庆钻探工程有限公司钻采工程技术研究院,四川成都610052 [2]中国石油西南油气田公司勘探事业部,四川成都610041

出　　处：《天然气勘探与开发》2024年第1期55-62,共8页Natural Gas Exploration and Development

摘　　要：四川盆地简阳—三台火山岩气藏排液测试期间地层出砂,导致测试管柱堵塞,需要探索适宜的防砂措施。因此,通过对气藏储层特点和单井出砂情况分析来寻找地层出砂原因;借鉴疏松砂岩的地层出砂预测方法,探讨火山岩气井排液测试期间的出砂可能性;优化排液测试期间油压控制等技术参数并开展现场试验,以评价技术措施的有效性。结果表明:①岩石黏土矿物含量高、胶结较弱、岩石强度不高、裂缝欠发育,排液测试期间井底流动压差过大超过出砂临界生产压差,诱发地层垮塌出砂;②基于测井资料的声波时差法和组合模量法可以定性预测简阳—三台火山岩气藏出砂难易程度,拉伸模型和经验模型公式可以较为方便地计算不同试油井段的临界出砂生产压差;③现场施工表明,阶梯式等压差控压放喷方法在排液测试期间能够有效削减地层出砂风险,是简阳—三台火山岩气藏探井试油的主要防砂手段。There exists sand production during the drainage of volcanic gas reservoirs in Jianyang-Santai area,Sichuan Basin,causing testing-string blockage.It is necessary to probe some appropriate measures against this sand production.Thus,not only reservoir char-acteristics but single-well sand production were analyzed to find out sand-production causes.And then,borrowed the method to predict this production in unconsolidated sandstone formations,the possibility of sand production was discussed for volcanic gas wells.Final-ly,a technical parameter of oil-pressure control during this drainage was optimized and tested on site to evaluate measure availability.Results show that(i)there is rich clay mineral in rocks with weak cementation,low intensity,and underdeveloped fractures.And the bottomhole flowing-pressure difference during the drainage is too high or higher than the critical production-pressure difference of sand production,which may induce formation collapse and thus sand production;(ii)two methods of both log-based interval travel-time and combined modulus can qualitatively predict the probability of sand production in Jianyang-Santai volcanic gas reservoirs,and the other drag and empirical model formulas can also easily calculate the critical difference in various formation-testing intervals;and(iii)in-situ practice demonstrates that,being a main measure against sand production during oil testing of exploratory wells in Jianyang-Santai volcanic gas reservoirs,the approach of step-by-step constant-pressure-difference managed bleeding can mitigate sand-production risks with effect.

关 键 词：四川盆地 简阳—三台火山岩气藏 火山碎屑熔岩 地层出砂 油压控制 中—晚二叠世 

分 类 号：TE37[石油与天然气工程—油气田开发工程]