四川盆地海相碳酸盐岩大气田形成主控因素与勘探思路  

Main factors controlling the formation of giant marine carbonate gas fields in the Sichuan Basin and exploration ideas

作　　者：李建忠[1] 谷志东[1] 鲁卫华[1] 姜华[1] 翟秀芬[1] 刘桂侠[1] 赵容容[2] LI Jianzhong;GU Zhidong;LU Weihua;JIANG Hua;ZHAI Xiufen;LIU Guixia;ZHAO Rongrong(PetroChina Research Institute of Petroleum Exploration and Development,Beijing 100083,China;PetroChina Southwest Oil&Gasfield Company,Chengdu,Sichuan 610051,China)

机构地区：[1]中国石油勘探开发研究院,北京市100083 [2]中国石油西南油气田公司

出　　处：《天然气工业》2021年第6期13-26,共14页Natural Gas Industry

基　　金：国家科技重大专项“四川盆地及邻区下古生界—前寒武系成藏条件研究与区带目标评价”(编号:2016ZX05004-005)。

摘　　要：目前,已在四川盆地震旦系—中三叠统发现了12个海相碳酸盐岩大气田,海相碳酸盐岩气藏已成为该盆地重要的天然气勘探领域与方向。为了进一步拓展该盆地海相碳酸盐岩气藏的勘探领域,在分析已发现海相碳酸盐岩大气田基本特征的基础上,系统总结了海相碳酸盐岩大气田形成的主控因素,进而提出了相应的勘探思路与评价方法。研究结果表明:①该盆地海相碳酸盐岩大气田以下寒武统、下志留统与上二叠统为主力烃源岩,发育上震旦统灯影组丘滩体、下寒武统龙王庙组颗粒滩、石炭系白云岩、上二叠统长兴组—下三叠统飞仙关组礁滩与下三叠统嘉陵江组—中三叠统雷口坡组颗粒滩等主要储层,以三叠系蒸发岩、下寒武统泥页岩与中二叠统泥岩为区域性盖层,具有下生上储的良好生储盖配置。②该盆地海相碳酸盐岩大气田形成主要受控于下述3个方面的因素——古构造背景与构造演化控制盆地“隆坳格局”的形成与分布,进而控制主力烃源岩、规模储层的形成与分布;古隆起、古斜坡的古地貌高带控制礁滩等高能沉积相带、大面积岩溶储层与古油藏、古气藏的分布;区域性与直接盖层控制大气田的空间分布与富集。结论认为,四川盆地海相碳酸盐岩大气田的勘探思路为隆坳格局定区带、地貌高带找滩体、地震预测找储层、古今圈闭定目标;评价方法为井—震—露头综合分析明确盆地岩相古地理格局,印模法、残厚法与地震相精细刻画礁(丘)滩体高能沉积相带,生—储—盖综合评价有利勘探区带与目标。So far,12 giant marine carbonate gas fields have been discovered in the Sinian-Middle Triassic of the Sichuan Basin and marine carbonate gas reservoirs have become an important natural gas exploration domain and direction in the Sichuan Basin.In order to further expand the exploration domain of marine carbonate gas reservoirs in the Sichuan Basin,this paper firstly analyzes the basic characteristics of the discovered giant marine carbonate gas fields.Based on this,the main factors controlling the formation of giant marine carbonate gas fields were summarized systematically and the corresponding exploration ideas and evaluation methods were put forward.And the following research results are obtained.First,the giant marine carbonate gas fields in the Sichuan Basin have high quality source-reservoir-cap assemblages of lower source rock and upper reservoir with the Lower Cambrian,the Lower Silurian and the Upper Permian as the major source rocks,the mound-shoal complex of the Upper Sinian Dengying Formation,the grain shoal of the Lower Cambrian Longwangmiao Formation,the Carboniferous dolomite,the reef-shoal complex of the Upper Permian Changxing Formation-Lower Triassic Feixianguan Formation and the grain shoal of the Lower Triassic Jialingjiang Formation-Middle Triassic Leikoupo Formation as the main reservoirs,and the Triassic evaporite,the Lower Cambrian shale and the Middle Permian mudstone as the regional cap rocks.Second,the formation of giant marine carbonate gas fields in the Sichuan Basin is mainly controlled by the following three factors:Palaeotectonic environment and tectonic evolution control the formation and distribution of"uplift-depression pattern"in the basin,and thus control the formation and distribution of major hydrocarbon source rocks and large-scale reservoirs;Palaeogeomorphic high belts of palaeo-uplifts and palaeo-slopes control the distribution of high-energy depositional facies belts(such as reefs and shoals),large-area karst reservoirs and ancient oil/gas reservoirs;Regional and direct c

关 键 词：四川盆地 海相碳酸盐岩 大气田 主控因素 隆坳格局 勘探思路 评价方法 

分 类 号：P618.13[天文地球—矿床学]