四川盆地东南部地区复杂构造带深层页岩气勘探进展与突破  

Deep shale gas exploration in complex structure belt of the southeastern Sichuan Basin:Progress and breakthrough

作　　者：胡东风[1] 魏志红[1] 李宇平[1] 刘珠江[1] 袁桃 刘晓晶[1] HU Dongfeng;WEI Zhihong;LI Yuping;LIU Zhujiang;YUAN Tao;LIU Xiaojing(Sinopec Exploration Company,Chengdu,Sichuan 610041,China)

机构地区：[1]中国石化勘探分公司,四川省成都市610041

出　　处：《天然气工业》2022年第8期35-44,共10页Natural Gas Industry

基　　金：国家自然科学基金企业创新发展联合项目“海相深层页岩源—储动态演化与页岩气富集规律研究”(编号:U19B6003-03-03)。

摘　　要：近年来,随着重庆涪陵、四川长宁—威远、云南昭通等国家级页岩气示范区的建成,中国页岩气产业得到快速发展,深层页岩气逐渐成为下一步天然气勘探开发的重要领域。但随着页岩储层埋深增加,勘探理论与评价技术、工程工艺技术等方面仍然存在着瓶颈问题和不适应性,需要不断攻关探索。中国石化在四川盆地东南部地区(以下简称川东南地区)复杂构造带五峰组—龙马溪组进行了近10年的勘探开发试验探索,为深层页岩气的勘探开发积累了丰富的经验。为此,系统梳理了该区域深层页岩气的勘探历程;总结了勘探过程中取得的理论认识进展、深层页岩气“甜点”地震预测及压裂监测技术的应用效果。研究结果表明:(1)在近10年的勘探历程中,在储层埋深和关键技术方面获得了重大突破,为深层页岩气规模效益开发提供了技术保障;(2)揭示了深层页岩气“超压富气”机理,建立了斜坡渐变型、断洼遮挡型、逆断层遮挡型3种页岩气富集模式;(3)形成了基于扰动体积模量的压力系数、区域应力背景约束的水平应力差、各向异性增强的裂缝五维地震预测3大技术系列;(4)形成了基于广域电磁法和“蜂窝”阵列微地震深层页岩气压裂监测关键技术。结论认为,四川盆地深层页岩气资源潜力大,川东南地区复杂构造带深层页岩气勘探开发技术的重大突破,坚定了向深层页岩气进军的信心,所形成的认识和关键技术将有力保障深层页岩气的高质量发展。In recent years, China’s shale gas industry has been developing quickly and deep shale gas has been gradually becoming the next important field of natural gas exploration and development as several national shale gas demonstration areas are built up, such as Chongqing Fuling, Sichuan Changning-Weiyuan and Yunnan Zhaotong. With the deepening of shale reservoirs, however, exploration theories and evaluation technologies and engineering technologies face bottlenecks and inadaptability and need continuous research. In the past 10 years, Sinopec has carried out trial exploration and development in Wufeng-Longmaxi Formation in the complex structure belt of the southeastern Sichuan Basin and accumulated rich experience in deep shale gas exploration and development. In this paper, the exploration history of deep shale gas in this area is reviewed systematically. Then, the theoretical understanding gained in the process of exploration and the application effects of the seismic prediction and fracturing monitoring technology of deep shale gas "sweet spot" are summarized. And the following research results are obtained. First, during nearly 10 years’ exploration, great breakthrough has been achieved in reservoir burial depth and key technology, so as to provide technical guarantee for the large-scale benefit development of deep shale gas. Second, the "overpressure gas enrichment" mechanism of deep shale gas is discovered, and three shale gas enrichment models are established, namely slope gradation model, faulted trough barrier model and reverse fault barrier model. Third, three series of technologies are mainly formed, including pressure coefficient based on disturbance bulk modulus, horizontal stress difference under the constraint of regional stress setting, and 5D seismic prediction of fracture of enhanced anisotropy. Fourth, the key technology for deep shale gas fracturing monitoring based on wide field electromagnetic method and "honeycomb" array microseismic is formed. In conclusion,there are huge potentials of d

关 键 词：四川盆地东南部 复杂构造带 深层页岩气 理论认识 关键技术 勘探突破 勘探进展 

分 类 号：P618.13[天文地球—矿床学]