四川盆地震旦系灯影组微生物岩多尺度结构特征 与沉积新模式

作    者：徐哲航1，2，3，李文正1，2，3，乔占峰1,2，3，陈政安4，兰才俊5，杨岱林5， 孙晓伟1，2，3，朱心健1，2，3，王永骁1，2，3，蔡 君1，王泽宇
单    位：中国石油杭州地质研究院；2 国家能源碳酸盐岩油气重点实验室；3 中国石油集团碳酸盐岩储层重点实验室； 4 中国石油勘探开发研究院；5 中国石油西南油气田公司勘探开发研究院
基金项目：
摘    要：
四川盆地震旦系灯影组微生物岩蕴含巨大资源潜力，从不同尺度描述微生物岩沉积结构有利于明确其分布 规律。以露头、岩心和薄片资料为基础，多尺度刻画了微生物岩中观尺度、微观尺度和宏观尺度的结构特征。结果表 明：灯影组大量发育微生物岩，根据中观结构特征可分为叠层石与凝块石两大类。此外，还发育内碎屑、核形石、鲕粒 及似球粒等颗粒—泥晶白云岩。灯影组在台地上发育11种岩相，这些岩相构成3种岩相组合，分别对应潮间—潮上、 浅潮下以及潟湖3种沉积环境。潮间—潮上环境常见窗格状与帐篷状暴露构造，并且发育多期叠置的微生物层宏观 建造；浅潮下环境发育透镜状微生物丘建造，以及砂屑颗粒—泥粒碳酸盐岩；潟湖环境以中—厚层状泥晶白云岩为 主，上部发育薄层的微生物岩沉积。由此建立四川盆地灯影组微生物岩沉积模式，可形成优质储层的微生物岩主要 发育在潮间—潮上带下部和浅潮下带上部。
关键词：微生物岩；沉积结构；岩相组合；沉积模式；灯影组；四川盆地

Multi-scale structural characteristics and a new depositional model of microbialites of the Sinian Dengying Formation in Sichuan Basin, SW China

Author's Name: XU Zhehang1,2,3, LI Wenzheng1,2,3, QIAO Zhanfeng1,2,3, CHEN Zheng'an4, LAN Caijun5, YANG Dailin5, SUN Xiaowei1,2,3, ZHU Xinjian1,2,3, WANG Yongxiao1,2,3, CAI Jun1, WANG Zeyu1
Institution: PetroChina Hangzhou Research Institute of Geology；. State Energy Key Laboratory of Oil and Gas in Carbonate Strata;Key Laboratory of Carbonate Reservoir, CNPC; Petrochina Research Institute of Petroleum Exploration & Development;
Abstract:
The Sinian Dengying Formation reveals a great resource potential in the central part of Sichuan Basin. Describing the microbialite depositional fabrics at multi-scale is beneficial for clarifying their distribution. Based on outcrop, core, and thin section data, this study characterizes the fabrics of microbialites at mesoscopic, microscopic, and macroscopic scales. Two types of microbialites, stromatolites and thrombolites, are identified in the Sinian Dengying Formation in Sichuan Basin. In addition, non-skeletal grains such as intraclasts, oncoids, ooids, and peloids have also been observed in the Dengying Formation. Based on these petrological characteristics, eleven lithofacies and three sedimentary cycles have been identified, which correspond to three depositional environments, including supratidalintertidal, shallow subtidal, and lagoon environments. In the supratidal-intertidal environment, the multi-stage microbial biostrome build-ups are observed with the frequently occurrence of the fenestral and teepee structures. The shallow subtidal environment exhibits lens-shaped microbial bioherm build-ups and grain-dominated intraclastic packstone/ grainstone. The lagoon cycle is dominated by medium to thick-bedded dolo-mudstone in the lower part. A depositional model for the microbialite of Dengying Formation in Sichuan Basin is established, in which high-quality microbial reservoir are predominantly developed in the lower supratidal-intertidal environment and the upper shallow subtidal environment.
Keywords: microbialite; sedimentary structure; lithofacies association; depositional model; Dengying Formation; Sich⁃ uan Basin
投稿时间： 2025-05-06  
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