四川盆地德阳—绵阳凹陷南缘二叠系栖霞组沉积演化及有利储层分布  

Sedimentary evolution and favorable reservoir distribution of Permian Qixia Formation in the southern margin of Deyang-Mianyang Sag,Sichuan Basin

作　　者：李亚 王尉 赵立可 刘冉 张玺华 陈延贵 黄天海 肖笛[2] LI Ya;WANGWei;ZHAO Like;LIU Ran;ZHANG Xihua;CHEN Yangui;HUANG Tianhai;XIAO Di(Research Institute of Exploration and Development,PetroChina Southwest Oil and Gas Field Company,Chengdu 610041,China;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Southwest Petroleum University,Chengdu 610500,China)

机构地区：[1]中国石油西南油气田公司勘探开发研究院,成都610041 [2]西南石油大学油气藏地质及开发工程国家重点实验室,成都610500

出　　处：《岩性油气藏》2025年第2期81-91,共11页Lithologic Reservoirs

基　　金：中国石油集团公司上游领域基础性前瞻性项目“残留型海相盆地构造-岩相古地理重建技术研究”(编号:2021DJ0501);中国石油-西南石油大学创新联合体科技合作项目“深层/超深层碳酸盐岩气田勘探开发基础理论与关键技术研究”(编号:2020CX010300);国家自然科学基金项目“四川盆地早中二叠世白云岩及储层差异成因与峨眉山大火成岩省幕式响应”(编号:42172166)联合资助。

摘　　要：综合利用岩心、岩屑、测井及地震等资料,对四川盆地德阳—绵阳凹陷南缘二叠系栖霞组沉积微相特征及演化过程进行了研究,并在此基础上划分出有利储集区带。研究结果表明:①德阳—绵阳凹陷南缘中二叠世栖霞期主要为缓坡相沉积,可进一步细分为浅水缓坡和深水缓坡—盆地等沉积亚相及多种微相,岩性以晶粒白云岩、亮晶生屑灰岩、泥晶生屑灰岩、生屑泥晶灰岩、泥晶灰岩及泥质灰岩为主。②栖一段沉积期,海水相对较深,滩相整体发育程度较低,仅在古地貌相对较高的高石梯区域沉积,岩性以泥晶生屑灰岩为主,沉积相受古地貌的影响较大;栖二下亚段沉积期,水体相对变浅,原古地貌高部位高石梯地区所发育的滩相受可容纳空间不足的影响而向古地貌相对低部位的磨溪地区侧向迁移,使地貌高差减小并逐渐发生反转;栖二上亚段沉积期,磨溪地区的滩相在垂向加积的同时,进一步向蓬莱地区迁移,沉积地貌高差减小但暂未发生反转。栖霞组滩相的发育受沉积微古地貌与相对海平面升降共同控制。③栖霞组以白云岩储层为主,其发育主要受岩相、岩溶及裂缝等因素控制,相对高能的颗粒滩由于沉积地貌相对较高,容易发生暴露而接受早期岩溶作用改造形成优质储层,高孔渗为进一步叠加白云石化作用提供了流体通道。磨溪地区高能滩最为发育,为研究区最有利储集区带,北部蓬莱地区次之,“德阳—绵阳”凹陷周缘有望成为下一个规模相控的天然气聚集区。Based on the comprehensive analysis of core samples,cuttings,well logging,and seismic data,this study investigates the sedimentary microfacies characteristics and evolutionary processes of the Permian Qixia Formation in the southern margin of the Deyang-Mianyang depression,Sichuan Basin.Furthermore,the research delineates favorable reservoir zones based on the aforementioned analysis.The results show that:(1)The southern margin of the Deyang-Mianyang depression in the middle Permian Qixia period is a set of carbonate ramp facies deposits,which are further subdivided into shallow Gentle Slope,deep Gentle Slope-basin subfacies and a variety of microfacies.The lithology is dominated by grained dolomite,sparry bioclastic limestone,micrite bioclastic limestone,bioclastic micrite limestone,micrite limestone and argillaceous limestone.(2)During the sedimentary period of Qi1 Member,the water is relatively deep and the overall development of the beach facies was low.It was only deposited in the Gaoshitai area with relatively high paleotopography.The lithology was dominated by micritic bioclastic limestone,and the sedimentary facies was greatly influenced by the paleotopography.During the lower of Qi2 sedimentary period,the water became shallower,and the shoal facies developed in Gaoshiti area in the upper part of the paleogeomorphology migrated laterally to Moxi area in the lower part of the paleogeomorphology due to the lack of space to accommodate it,the difference of sedimentary geomorphology decreased and reverse.During the upper of Qi2 sedimentary period,the shoal facies in the Moxi area not only experienced vertical accretion but also progressively migrated and expanded towards the Penglai region.Although the topographic relief of the depositional environment decreased during this phase,no significant inversion occurred.(3)The Qixia Formation is mainly composed of dolomite reservoirs,and its development is mainly controlled by factors such as lithology,karst,and fractures.The relatively high-energy particle beach,du

关 键 词：颗粒滩 沉积古地貌 碳酸盐缓坡 早期岩溶作用 白云石化作用 栖霞组 二叠系 德阳—绵阳凹陷 四川盆地 

分 类 号：TE122[石油与天然气工程—油气勘探] P618.13[天文地球—矿床学]