泥岩隔层发育背景下的河道砂岩气藏剩余气挖潜实践——以新场气田JS_(2)^(2)气层为例  

Practice of potential tapping of remaining gas in channel sandstone gas reservoir under the background of mudstone interlayers development: A case study of JS_(2)^(2) gas layer in Xinchang Gas Filed

作　　者：黎虹玮 袁剑 赵志川 周志林[2] LI Hongwei;YUAN Jian;ZHAO Zhichuan;ZHOU Zhilin(Exploration&Development Research Institute,Sinopec Southwest Oil and Gas Company,Chengdu,Sichuan 610041,China;No.1 Gas Production Plant,Sinopec Southwest Oil and Gas Company,Deyang,Sichuan 610800,China)

机构地区：[1]中国石化西南油气分公司勘探开发研究院,四川成都610041 [2]中国石化西南油气分公司采气一厂,四川德阳610800

出　　处：《油气藏评价与开发》2022年第2期365-372,390,共9页Petroleum Reservoir Evaluation and Development

基　　金：国家科技重大专项“薄层窄河道致密砂岩气藏工程设计关键技术”(2016ZX05048-004-002)。

摘　　要：新场气田JS_(2)^(2)气层为三角洲前缘亚相分流河道微相砂体沉积,部分砂体区域发育泥岩隔层,形成两期河道沉积,部分双层砂体发育气井仅射孔压裂其中一层,另一层砂体可能受泥岩隔层隔挡未被动用,但目前泥岩隔层分布规律认识不清,隔层垂向封隔性能尚未有先例验证,制约了该层剩余气的开发。通过建立JS_(2)^(2)气层隔层测井曲线识别标准,对单井进行小层对比划分,开展隔层发育规模和平面分布规律研究,利用老井挖潜探索河道砂岩内部泥岩隔层垂向封隔性能。结果表明,泥岩隔层主要分布在JS_(2)^(2)气藏东部,厚1~15 m,总体表现为两厚夹一薄特征。利用A1井挖潜实践,原未射孔压裂层经射孔和加砂压裂后增产明显,首次证实A1井区10 m泥岩隔层具有较好垂向封隔性能,该成果将对JS;气层剩余气开发提供新思路和实践依据,对提高整个气藏采收率具有重要意义。The JS_(2)^(2) gas reservoir in the Xinchang Gas Field is the microfacies of distributary channel deposit in the delta front subfacies. The mudstone interlayer developed in some sandstone layers form the channel sediments twice. For some gas wells with double developed sand layers, the perforation and fracturing are carried out only in one of the two layers, while the rest may be blocked by mudstone interlayer, resulting in its untapped situation. However, the understanding of the distribution rule of the mudstone interlayer is unclear, and the sealing performance of interlayers hasn’t been verified by precedent, limiting the development of the remaining gas in this reservoir. By the establishment of the logging curve identification standards of the interlayer, the interlayer of every single well is identified and divided, and the development scale and plane distribution rule of the interlayer are studied. And then, the old wells are used to explore the vertical sealing performance of the mudstone interlayer inside the channel sandstone. The study results show that the mudstone interlayer, with the thickness of 1~15 meters, is mainly distributed in the east of the JS_(2)^(2) gas reservoir, and has the characteristic of one thin-line area laying between two thick areas along the distribution direction. In the application of potential tapping of Well-A1, the production obviously increase after the perforation and sand-fracture, firstly verifying that the mudstone interlayer with the thickness of 10 meters in A1 well area has better vertical sealing performance. This achievement will provide new ideas and practical basis for the development of remaining gas in the JS_(2)^(2) gas reservoir, and is of great significance for improving the recovery rate of the entire gas reservoir.

关 键 词：新场气田 JS_(2)^(2)气层 隔层 剩余气 老井挖潜 

分 类 号：TE37[石油与天然气工程—油气田开发工程]