大兴安岭中南段霍林河地区火山喷发旋回划分及特征  

Volcanic eruption cycles division and characteristics in Huolinhe area ofthe central and southern Greater Khingan Mountain

作　　者：刘永高 LIU Yonggao(Inner Mongolia Tenth Geological Mineral Exploration and Development Co.,Ltd.,Inner Mongolia Chifeng 024000,China)

机构地区：[1]内蒙古第十地质矿产勘查开发有限责任公司,内蒙古赤峰024000

出　　处：《中国地质调查》2024年第4期50-61,共12页Geological Survey of China

基　　金：中国地质调查局“内蒙古1∶5万包尔呼吉尔塔拉(L50E015023)、巴润哈尔努尔(L50E015024)、沙尔呼热(L50E016023)、查布干其敖瑞(L50E016024)、阿尔布拉格敖包(L50E017023)、呆布嘎音乌拉(L50E017024)、甘珠尔敖包(L50E018023)、罕山林场(L50E018024)幅区域地质调查(编号:DD20160048-11)”项目资助。

摘　　要：大兴安岭中南段霍林河地区自中生代以来火山活动强烈,形成了广泛分布的中侏罗世—早白垩世中酸性火山岩,是研究中生代火山喷发演化特征的理想地区。通过在霍林河地区运用“火山岩岩性与岩相-火山构造-岩石地层”三重填图方法进行填图,对岩性、岩相、火山喷发旋回及韵律特征进行总结分析。结果显示:霍林河地区出露岩性种类可分为普通火山碎屑岩、熔结火山碎屑岩、熔岩、沉积火山碎屑岩和火山碎屑沉积岩、潜火山岩共6类,岩相主要有爆发相、火山碎屑流相、火山爆发崩塌相、火山喷发沉积相、溢流相、火山颈相、侵出相及潜火山岩相共8类;本区火山活动可划分为新民期((163.7±1.7)~(160.0±4.0)Ma)、塔木兰沟期((164.2±4.1)~(159.7±2.7)Ma)、满克头鄂博期((163.4±1.3)~(157.0±1.1)Ma)、玛尼吐期((151.4±2.6)~(144.0±2.8)Ma)、白音高老期((141.7±1.3)~(128.6±1.4)Ma)、梅勒图期((133.4±1.5)~(127.7±1.4)Ma)共6个火山喷发旋回,对应6个组级火山岩地层单元。在中侏罗世,霍林河地区的火山活动不稳定,少量酸性火山碎屑岩爆发并伴有较多间歇期,晚期主要为中性熔岩的平静溢流;晚侏罗世火山活动表现为酸性火山碎屑岩的强烈爆发,并伴随有少量中酸性火山熔岩溢出;早白垩世早期早阶段火山活动表现为酸性火山碎屑岩的强烈爆发作用,早期晚阶段火山活动表现为中基性火山熔岩的平静溢流。霍林河地区的火山活动代表了典型的大兴安岭中南段中生代火山喷发旋回特征,研究成果有助于对大兴安岭中南段中生代火山喷发旋回进行合理划分,促进不同地区火山岩岩性组合、火山活动特征、岩相建造及火山地层的深入对比研究。Huolinhe area in the central and southern Greater Khingan Mountain has experienced strong volcanic activities since Mesozoic Era,and widely distributed intermediate acidic volcanic rocks were formed from Middle Jurassic to Early Cretaceous,which is a desirable area for evolution characteristics research of volcanic eruption during Mesozoic Era.The triple mapping method of“volcanic lithology and lithofacies,volcanic structure,and rock strata”was used in Huolinhe area to summarize and analyze the lithology,lithofacies,volcanic eruption cycles,and rhythmic characteristics.The result shows that the types of exposed rock types in this area can be divided into six categories,including ordinary pyroclastic rocks,fused pyroclastic rocks,lava,sedimentary pyroclastic rocks and pyroclastic sedimentary rocks,and latent volcanic rock.And there are eight types of lithofacies,including explosive facies,pyroclastic flow facies,volcanic eruption collapse facies,overflow facies,volcanic eruption sedimentary facies,volcanic neck facies,intrusive facies,and subvolcanic lithofacies.The volcanic activity in this area can be divided into six volcanic eruption cycles:Xinmin period((163.7±1.7)~(160.0±4.0)Ma),Tamulangou period((164.2±4.1)~(159.7±2.7)Ma),Manketouebo period((163.4±1.3)~(157.0±1.1)Ma),Manitu period((151.4±2.6)~(144.0±2.8)Ma),Baiyingaolao period((141.7±1.3)~(128.6±1.4)Ma),and Meiletu period((133.4±1.5)~(127.7±1.4)Ma),corresponding to the six volcanic rock stratigraphic formation.Volcanic activity was unstable in Huolinhe area during Middle Jurassic.A small amount of acidic volcanic debris erupted and were accompanied by many intermittent periods,followed by mainly calm overflow of neutral lava in the late phase.There was a strong eruption of acidic volcanic clastic rocks during Late Jurassic,accompanied by a small amount of medium acidic volcanic lava overflow.In the early stages of Early Cretaceous,the early stage volcanic activities were characterized by strong eruption of acidic volcanic clastic rocks,and t

关 键 词：火山岩区填图 火山喷发旋回 韵律 火山构造 岩性 岩相 

分 类 号：P588.141[天文地球—岩石学]