输导层(体)非常规天然气勘探理论与实践——四川盆地新类型页岩气与致密砂岩气突破的启示  

Theory and practice of unconventional gas exploration in carrier beds:Insight from the breakthrough of new type of shale gas and tight gas in Sichuan Basin,SW China

作　　者：郭彤楼[1] 熊亮[1] 叶素娟[1] 董晓霞 魏力民 杨映涛 GUO Tonglou;XIONG Liang;YE Sujuan;DONG Xiaoxia;WEI Limin;YANG Yingtao(Sinopec Southwest Oil&Gas Company,Chengdu 610041,China)

机构地区：[1]中国石油化工股份有限公司西南油气分公司,成都610041

出　　处：《石油勘探与开发》2023年第1期24-37,共14页Petroleum Exploration and Development

基　　金：中国石油化工股份有限公司科技项目(P22081);国家科技重大专项(2016ZX05002-004)。

摘　　要：针对四川盆地海相页岩层系寒武系筇竹寺组历经多年页岩气勘探未获重大突破、三叠系须家河组致密气一直未能实现规模商业建产的问题,在对老井反馈分析的基础上,结合致密气、页岩气的聚集机理以及钻井过程中油气显示、开发过程中产量压力变化等特征,提出转变勘探开发思路,从源、储勘探转向输导层(体)勘探,把有效烃源岩、有效输导层(体)和有效砂岩(页岩)层的有机组合作为成藏体,建立了输导层(体)非常规天然气形成富集模式。实践应用上取得2项成效:(1)指导筇竹寺组低有机质丰度粉砂质页岩勘探取得重大突破,改变了只在富有机质黑色页岩中寻找页岩气的传统思维,也实现了四川盆地新区、新层系、新类型页岩气的突破与勘探开发向多层系的转变;(2)实现了须家河组致密砂岩难动用储量的勘探突破和高效开发,破解了须家河组致密砂岩层产量不高、裂缝带产量不稳的难题,推动了致密砂岩气从有储量无产量向有效动用的转变,提升了致密砂岩气的勘探开发潜力。Unconventional gas in the Sichuan Basin mainly includes shale gas and tight gas. The development of shale gas is mainly concentrated in the Ordovician Wufeng Formation–Silurian Longmaxi Formation, but has not made any significant breakthrough in the Cambrian Qiongzhusi Formation marine shale regardless of exploration efforts for years. The commercial development of tight sandstone gas is mainly concentrated in the Jurassic Shaximiao Formation, but has not been realized in the widespread and thick Triassic Xujiahe Formation. Depending on the geological characteristics of the Qiongzhusi Formation and Xujiahe Formation, the feedback of old wells was analyzed. Then, combining with the accumulation mechanisms of conventional gas and shale gas, as well as the oil/gas shows during drilling, changes in production and pressure during development, and other characteristics, it was proposed to change the exploration and development strategy from source and reservoir exploration to carrier beds exploration. With the combination of effective source rock,effective carrier beds and effective sandstone or shale as the exploration target, a model of unconventional gas accumulation and enrichment in carrier beds was built. Under the guidance of this study, two significant results have been achieved in practice. First, great breakthrough was made in exploration of the silty shale with low organic matter abundance in the Qiongzhusi Formation, which breaks the traditional approach to prospect shale gas only in organic-rich black shales and realizes a breakthrough in new areas, new layers and new types of shale gas and a transformation of exploration and development of shale gas from single-layer system, Longmaxi Formation,to multi-layer system in the Sichuan Basin. Second, exploration breakthrough and high-efficient development were realized for difficult-to-produce tight sandstone gas reserves in the Xujiahe Formation, which helps address the challenges of low production and unstable production of fracture zones in the Xujiahe For

关 键 词：四川盆地 输导层(体) 致密气 页岩气 粉砂质页岩 寒武系筇竹寺组 三叠系须家河组 

分 类 号：TE122[石油与天然气工程—油气勘探]