盆地火山岩相研究进展——基性火山熔岩及水下喷发火山岩相新成果  

Progress of Basin Volcanic Facies:New Results of Intermediate-Mafic Volcanic Lava and Volcanic Facies of Subaqueous Eruption

作　　者：单玄龙[1] 邹玉洁 衣健[1] 郝国丽[1] 李昂[1] 石云倩 陆俊杰 李嘉慧 Shan Xuanlong;Zou Yujie;Yi Jian;Hao Guoli;Li Ang;Shi Yunqian;Lu Junjie;Li Jiahui(College of Earth Sciences,Jilin University,Changchun 130061,China)

机构地区：[1]吉林大学地球科学学院,长春130061

出　　处：《吉林大学学报（地球科学版）》2024年第3期721-734,共14页Journal of Jilin University：Earth Science Edition

基　　金：国家自然科学基金项目(41972313,41790453)。

摘　　要：火山岩相是火山物质喷发类型、搬运方式和就位环境与状态的总和,划分火山岩相是刻画盆地火山岩分布,寻找火山岩有利储层的基础,对盆地火山岩油气勘探具有重要作用。前人以火山岩的“岩性-组构-成因”为分类依据,建立了盆地火山岩“5相15亚相”分类方案,极大推动了我国盆地深层火山岩勘探进程。目前,我国大规模的盆地火山岩油气勘探已经走过了20余年的历程,随着勘探的深入对该岩相分类方案进行了不断地完善和丰富:针对基性火山熔岩,建立了基性溢流相,以及板状熔岩流、辫状熔岩流和玻质碎屑岩3种亚相及相模式;针对湖盆水下喷发,建立了水下爆发相,以及气携水下热碎屑流、水携火山高密度流和水下降落3种亚相及相模式,形成了“7相21亚相”的新的分类方案。基性溢流相中,辫状熔岩流亚相储层发育条件最好,玻质碎屑岩亚相次之,板状熔岩流亚相稍差;水下爆发相中,气携水下热碎屑流亚相控制有效储层的空间分布。基性溢流相的建立,克服了基性熔岩因单层厚度薄,钻井和地震亚相刻画困难等问题;水下爆发相的建立,实现了沉积盆地从陆上到水下不同喷发环境火山岩相的准确刻画。两种岩相的建立为进一步探索基性火山熔岩发育区和水下喷发火山碎屑岩发育区储层发育规律,寻找有利储层提供了基础。Volcanic facies is the sum of volcanic material eruption type,transport mode,emplacement environment and state.The classification of volcanic facies is the basis for characterizing the distribution of volcanic rocks in a basin and searching for favorable volcanic reservoirs,which plays an important role in the exploration of volcanic oil and gas in a basin.Based on the“lithology,petrofabric and petrogenesis”of volcanic rocks,a classification scheme of“5 facies and 15 subfacies”of volcanic rocks in the basin was established,which greatly promoted the exploration process of deep volcanic rocks in China basins.At present,the large-scale volcanic oil and gas exploration in basins in China has gone through a course of more than 20 years,and with the in-depth exploration,the lithofacies classification scheme has been improved and enriched:For the intermediate-mafic volcanic lava,the intermediate-mafic effusive lava flow facies has been established,and three sub-facies have been divided into braided lava flow unit,tabular lava flow unit and the lava dome.Aiming at subaqueous volcanic eruption in lacustrine basin,three subfacies and facies models of subaqueous volcanic eruption phase,gas-supported hot pyroclastic flow subfacies,water-laid density current subfacies and subaqueous fallout subfacies are established.A new classification scheme of“7 facies and 21 subfacies”was formed.In the intermediate-mafic volcanic lava facies,the braided lava flow subfacies has the best development conditions,followed by the hyaloclastic rock subfacies and the tabular lava flow subfacies.Gas-supported hot pyroclastic flow subfacies control the spatial distribution of effective reservoirs in the subaqueous volcanic eruption facies.The establishment of the intermediate-mafic effusive lava flow facies overcomes the difficulty in characterizing the subfacies of the basic lava due to the thin monolayer thickness and the difficulty in drilling and seismic characterization.The establishment of subaqueous volcanic explosive facies has

关 键 词：火山岩相 基性溢流相 水下爆发相 火山岩储层 盆地 

分 类 号：P618.13[天文地球—矿床学]