产能剖面测试技术在常压页岩气开发中的应用

Application of Productivity Profile Testing Technology in Normal-pressure Shale Gas Development

安场向斜常压页岩气井生产时间相对较短,对其生产规律的认识相对薄弱。为了给后期井位部署、井眼轨迹设计、压裂工艺及规模、排采制度优化提供科学量化依据,基于分布式光纤温度及声波测量(DTS+DAS)原理及其配套工艺技术,对测试井产能剖面测井资料进行解释分析,计算出9mm油嘴稳定生产制度下的各段簇产气量、产水量以及产气、产水贡献率,结合钻井、录井、测井、压裂、试气等基础资料,对比分析测试井的产出规律及其影响因素。分析结果表明,各段产气量与加砂强度、用液强度呈正相关,线性相关率分别为28.45%和30.01%;各段产气量与射孔簇开启率正相关关系明显,线性相关率为65.51%;各簇产气量与随钻气测全烃值及总有机碳含量呈正相关,线性相关率分别为37.97%和24.12%;产气量与含气量、孔隙度、渗透率等其他地质参数也具有一定的线性相关性。产水量与用液强度、射孔簇开启率呈正相关,孔隙度、渗透率较高的层位产水量比较高。建议后期同区块水平段钻井穿行轨迹的设计应选择随钻全烃值相对较高、有机碳含量高、孔隙度相对高、渗透率较高的优质页岩层。

Normal-pressure shale gas wells at Anchang Syncline are produced for a relatively short time,and the understanding of their production modes is relatively weak.To provide a scientific and quantitative basis for later well location deployment,wellbore trajectory design,fracturing technology and scale,and drainage system optimization,logging data of the productivity profile of the test wells are interpreted and analyzed based on the principle and its supporting technology of distributed optical fiber temperature and acoustic survey(DTS+DAS).Gas production,water production,and the contribution rate of each cluster under the stable production system of 9mm choke are calculated,and the well production patterns and their influencing factors are analyzed combined with the basic data of drilling,well logging,mud logging,fracturing,gas testing,and others.The result shows that the gas production of each section is positively correlated with the sanding strength and liquid consumption,and the linear correlation rates are 28.45%and 30.01%respectively.The gas production of each section is positively correlated with the perforation cluster opening rate,and the linear correlation rate is 65.51%.The gas production of each cluster is positively correlated with the total hydrocarbon value and total organic carbon content measured while drilling and the linear correlation rates are 37.97%and 24.12%respectively.The gas production is also correlated linearly to other geological parameters such as gas content,porosity,and permeability.Water production is positively correlated with liquid consumption and perforation cluster opening rate,and layers with higher porosity and permeability have higher water production.It is recommended that high-quality shale layers with relatively high total hydrocarbon value while drilling,high organic carbon content,relatively high porosity,and high permeability should be selected for the later design of drilling trajectories of the horizontal section in the same block.