四川盆地下寒武统龙王庙组白云岩分布与控制因素  

Distribution and Controlling Factors of Dolostone in Lower Cambrian Longwangmiao Formation,Sichuan Basin

作　　者：杨伟强 黎霆 兰才俊 卢朝进 陈浩如 李平平[1,2] 邹华耀[1,2] Yang Weiqiang;Li Ting;Lan Caijun;Lu Chaojin;Chen Haoru;Li Pingping;Zou Huayao(State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum,Beijing 102249,China;College of Geosciences,China University of Petroleum,Beijing 102249,China;School of Earth Resources,China University of Geosciences,Wuhan 430074,China)

机构地区：[1]中国石油大学油气资源与探测国家重点实验室,北京102249 [2]中国石油大学地球科学学院,北京102249 [3]中国地质大学资源学院,湖北武汉430074

出　　处：《地球科学》2024年第7期2388-2406,共19页Earth Science

基　　金：国家自然科学基金项目(No.42172152)。

摘　　要：白云岩的强抗压溶能力是龙王庙组深层-超深层碳酸盐岩储层孔隙保存的关键,但现今发现龙王庙组白云岩时空分布存在较大差异,为了完善龙王庙组白云岩储层的分布预测,白云岩类型与分布、白云岩化机制与模式成为期待解决的关键问题.运用岩石学、沉积学、层序地层学和地球化学,围绕白云岩发育分布,取得了以下认识.四川盆地龙王庙组发育五类与白云岩化相关的岩石类型.白云岩的时空分布受古地貌和海平面升降的控制,平面上,白云岩主要分布在川中古隆起和川北中部;垂向上,白云岩分布受三级和四级海平面升降控制,三级层序中上部的四级层序白云岩化程度高;白云岩化流体为海水或一定蒸发程度的海水,并建立了三种准同生白云岩化模式.The strong pressure dissolution resistance of dolostone is the key to the preservation of deep-ultra-deep carbonate reservoirs in the Longwangmiao Formation.However,it is found that there are great differences in the spatial and temporal distribution of dolostone in the Longwangmiao Formation.In order to improve the distribution prediction of dolostone reservoir in the Longwangmiao Formation,the type and distribution of dolostone,dolomitization mechanism and model have become the key issues to be solved.Based on petrology,sedimentology,sequence stratigraphy and geochemistry,this study focuses on the development and distribution of dolostone in the Longwangmiao Formation,Sichuan Basin.As a result,the following understandings are obtained.Five rock types related to dolostone have been identified in the Longwangmiao Formation,Sichuan Basin.The spatial and temporal distribution of dolostone is controlled by the paleogeomorphology and the sea level fluctuation.The dolostone is mainly distributed in the central Sichuan uplift and the central part of northern Sichuan Basin.The vertical distribution of dolostone is controlled by the coupling of the 3rd order and 4th order sea level change.The 4th order sequence,located in the middle and upper parts of the 3rd order sequence,has high dolomitization degree.The dolomitization fluid in the Longwangmiao Formation is seawater or seawater with a certain degree of evaporation,and three penecontemporaneous dolomitization models are established in the Longwangmiao Formation.

关 键 词：四川盆地 龙王庙组 白云岩分布 白云岩化模式 控制因素 石油地质 

分 类 号：P618.13[天文地球—矿床学]