渝西五峰组—龙马溪组深层页岩沉积相与岩相分布特征
Characteristics of Sedimentary Facies and Lithofacies Distribution of Deep Shale of Wufeng Formation-Longmaxi Formation
李维 1雷治安 1陈维铭 1孟森淼 2陈利 1蒲彬 2孙超亚 1郑婕3
作者信息
- 1. 重庆页岩气勘探开发有限责任公司,重庆 401121
- 2. 中国石油集团川庆钻探工程有限公司,四川 成都 610051
- 3. 成都加里东油气技术发展有限公司,四川 成都 610095
- 折叠
摘要
渝西五峰组—龙马溪组深层页岩气是中国页岩气下一步勘探开发的重要区域.但该区块页岩岩相组分复杂、空间变化剧烈,缺少对沉积相与岩相分布特征的精细描述,影响了页岩气"甜点"段识别与优选.为此,通过岩心薄片、扫描电镜、X射线衍射、FMI成像、核磁共振、有机碳分析等研究手段,对渝西五峰组—龙马溪组深层页岩沉积相与岩相分布特征进行细致研究.结果表明:研究区整体处于滨外陆棚相沉积,可划分为浅水陆棚、半深水陆棚和深水陆棚3 种对页岩气评价指标具有不同控制作用的亚相;主要发育 10 种岩相,岩相由西北至南东沉积较为稳定,龙一11 小层发育硅质页岩、富泥硅质页岩、富泥-硅混合质页岩等 3 种主力岩相;根据沉积相与岩相分布特征,预测Z203 井区五峰组—龙马溪组资源潜力巨大,为下步有利勘探区.该研究结果深化了研究区页岩储层纵向分布的认识,可为后续页岩气高效开发提供数据支撑.
Abstract
The deep shale gas of Wufeng Formation-Longmaxi Formation in the western Chongqing is an essential area for the next exploration and development of shale gas in China.However,the shale petrographic components in this block are complex and spatially variable,and the fine description of the distribution characteristics of sedimen-tary facies and lithofacies is lacking,which affect the identification and preference of shale gas"sweet spot"sec-tions.To this end,the sedimentary facies and lithofacies of the deep shale of Wufeng Formation-Longmaxi Forma-tion in western Chongqing were studied in detail through core thin section,scanning electron microscopy,Xray dif-fraction,FMI imaging,nuclear magnetic resonance,organic carbon analysis and other research tools.The results show that the whole study area is in the deposition of offshore shelf phase,which can be divided into three subfa-cies:shallow water shelf,semi-deep water shelf,and deep water shelf that have different controlling effects on the shale gas;10 main lithofacies are developed,and the lithofacies are more stably deposited from the northwestern to the southeastern part of the area,and Longyi11 layer develops three main lithofacies:siliciclastic shale,mud-rich siliciclastic shale,and mud-siliciclastic shale.According to the distribution characteristics of the sedimentary faci-es and lithofacies,it is predicted that the resource potential of this section in Well Z203 Area is huge,and it is a favorable exploration area in the next step.The results of this study deepen the understanding of the vertical distri-bution of shale reservoirs in the study area and provide data support for the subsequent efficient development of shale gas.
关键词
深层页岩气/沉积相特征/岩相分布/五峰组—龙马溪组/渝西区块Key words
deep shale gas/sedimentary facies characteristic/lithofacies distribution/Wufeng Formation-Longmaxi Formation/western Chongqing Area引用本文复制引用
基金项目
"十四五"中国石油上游领域前瞻性基础性科技项目(2021DJ19)
出版年
2024
国家科技期刊平台
NSTL
万方数据