湖盆水下喷发火山岩相类型、特征与储集意义——以松辽盆地南部查干花地区白垩系为例  

Subaqueous volcanic eruptive facies,facies model and its reservoir significance in a continental lacustrine basin:A case from the Cretaceous in Chaganhua area of southern Songliao Basin,NE China

作　　者：单玄龙[1] 牟汉生 刘玉虎 李瑞磊 朱建峰 石云倩 冷庆磊 衣健[1] SHAN Xuanlong;MU Hansheng;LIU Yuhu;LI Ruilei;ZHU Jianfeng;SHI Yunqian;LENG Qinglei;YI Jian(College of Earth Sciences,Jilin University,Changchun 130061,China;SINOPEC Northeast Oil and Gas Company,Changchun 130062,China)

机构地区：[1]吉林大学地球科学学院,长春130061 [2]中国石油化工集团有限公司东北油气分公司,长春130062

出　　处：《石油勘探与开发》2023年第4期719-730,共12页Petroleum Exploration and Development

基　　金：国家自然科学基金面上项目(41972313);国家自然科学基金重大项目(41790453)。

摘　　要：为解决传统的陆上和海域火山碎屑岩岩相及相模式难以反映湖盆水下火山机构特征的问题,以松辽盆地长岭断陷查干花地区白垩系火石岭组凝灰岩丘为研究对象,探讨水下喷发火山碎屑岩岩相并建立相模式。研究表明,水下喷发火山碎屑岩可分为2种相4种亚相,其中2种相为水下爆发相和喷发间歇期形成的火山沉积相。水下爆发相可进一步分为气携水下热碎屑流、水携火山密度流和水下降落3种亚相;火山沉积相由含外碎屑火山碎屑沉积岩1种亚相构成。松辽盆地水下喷发形成典型的凝灰岩丘相模式,凝灰岩丘通常由多个水下喷发堆积单元叠加构成,可分为近源和远源两个相组。近源相组完整的堆积单元从下到上依次由含外碎屑火山碎屑沉积岩亚相-气携水下热碎屑流亚相-水携火山高密度流亚相和水下降落亚相构成;远源相组的堆积单元以发育水下降落亚相为主,夹有多个薄层水携高密度流亚相沉积。气携水下热碎屑流亚相和火山沉积相含外碎屑火山碎屑沉积岩亚相是陆相湖盆水下喷发有利储集层发育的优势岩相。The conventional lithofacies and facies model of subaerial and marine pyroclastic rocks cannot reflect the characteristics of subaqueous volcanic edifice in lacustrine basins.In order to solve this problem,the lithofacies of subaqueous eruptive pyroclastic rocks is discussed and the facies model is established by taking the tuff cone of Cretaceous Huoshiling Formation in the Chaganhua area of the Changling faulted depression,Songliao Basin as the research object.The results indicate that the subaqueous eruptive pyroclastic rocks in the Songliao Basin can be divided into two facies and four subfacies.The two facies are the subaqueous explosive facies and the volcanic sedimentary facies that is formed during the eruption interval.The subaqueous explosive facies can be further divided into three subfacies:gas-supported hot pyroclastic flow subfacies,water-laid density current subfacies and subaqueous fallout subfacies.The volcanic sedimentary facies consists of pyroclastic sedimentary rocks containing terrigenous clast subfacies.A typical facies model of the tuff cone that is formed by subaqueous eruptions in the Songliao Basin was established.The tuff cone is generally composed of multiple subaqueous eruption depositional units and can be divided into two facies associations:near-source facies association and far-source facies association.The complete vertical succession of one depositional unit of the near-source facies association is composed of pyroclastic sedimentary rocks containing terrigenous clast subfacies,gas-supported hot pyroclastic flow subfacies,water-laid density current subfacies and subaqueous fallout subfacies from bottom to top.The depositional unit of the far-source facies association is dominated by the subaqueous fallout subfacies and contains several thin interlayered deposits of the water-laid density current subfacies.The gas-supported hot pyroclastic flow subfacies and the pyroclastic sedimentary rocks containing terrigenous clast subfacies are favorable subaqueous eruptive facies for rese

关 键 词：陆相湖盆 松辽盆地 查干花地区 白垩系火石岭组 水下喷发 火山岩相 凝灰岩丘 

分 类 号：TE122[石油与天然气工程—油气勘探]