基于重力剖面的长白山天池火山地壳岩浆囊建模  

Changbaishan Tianchi volcano crustal magma chambers modeling with gravity profile

作　　者：管彦武[1,2] 崔承赞 杨国东 刘嘉麒[1,4] 李允秀 吴昌桓 金旭[1,2] 吴燕冈 GUAN YanWu;CHOI SungChan;YANG GuoDong;LIU JiaQi;LEE YounSoo;OH ChangWhan;JIN Xu;WU YanGang(College of Geo-exploration Science and Technology,Jilin University,Changchun 130026,China;Key Laboratory of Applied Geophysics,MNR,Changchun 130026,China;Christian-Albrechts-Universitaet zu Kiel,zu Kiel 24118,Germany;Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China;Pohang University of Science and Technology,Pohang 37673,Korea;The Earth and Environmental Science System Research Center,Department of Earth and Environmental Sciences,Chonbuk National University,Jeonju 54896,Republic of Korea)

机构地区：[1]吉林大学地球探测科学与技术学院,长春130026 [2]自然资源部应用地球物理重点实验室,长春130026 [3]基尔大学,基尔24118 [4]中国科学院地质与地球物理研究所,北京100029 [5]浦项科学技术大学,浦项37673 [6]全北国立大学地球与环境科学系地球与环境科学系统研究中心,全州54896

出　　处：《岩石学报》2020年第12期3840-3852,共13页Acta Petrologica Sinica

基　　金：国家重点研发计划项目(2020YFE0201300);中国地质调查局项目(DD20201118);国家自然科学重点基金项目(40930314);吉林大学基本科研业务费(450060481571、450060521012)联合资助。

摘　　要：长白山天池火山是中国最具潜在喷发危险的多成因复式火山,在近2000年来,曾经发生过世界上最大规模的喷发。为了进一步研究长白山天池火山的潜在危险,有必要研究火山的岩浆囊位置和分布。为此,在长白山天池火山开展了一条南北方向的重力剖面测量。结合前人工作,如地震勘探P波速度反演和大地电磁测深(MT)电阻率反演,以及地质信息,采用人机交互的形式,建立了一条长约150km的密度模型。从建模结果图中可以发现:(1)长白山天池下方存在地壳岩浆囊;(2)长白山天池北坡地壳存在一个高阻、低密度体,深度在7~15km,距离天池2~10km,可能是富含气体的岩浆囊;(3)在南坡和北坡大约3km深度处普遍存在一个岩浆岩层;(4)在天池下存在一个已经塌陷堵塞的火山颈。Changbaishan Tianchi volcano is a multiple genesis compound volcano with the most potential risk of the eruption in China.The biggest eruption in the world has occurred in the last 2000 years.To further research the Changbaishan Tianchi volcano’s potential dangerousness,we must ascertain the location of magma chambers,main fracture geological formations.Therefore,we launched a north-south gravity exploration profile in Changbaishan Tianchi volcano.Combined with previous work,such as the P-wave velocity inversion results of the seismic exploration section,the resistivity inversion section of MT exploration,geological structure,and other information incorporated into a piece of modeling the density distribution by interactive interpretation method.As can be seen from the model:(1)Changbaishan Tianchi volcano shallow magma chambers exist beneath the earth’s crust;(2)On the northern slope of Changbaishan Tianchi volcano upper crust section,there is a shallow high-resistivity,low-density body,at a distance of approximately2~10 km from the lake underground,depth of about 7~15 km,maybe magma chamber rich in gas;(3)There was generally a magmatic stratum at a depth of about 3 km on the south and north slopes;(4)In the bottom of Tianchi lake,there is a plugged volcano neck.

关 键 词：长白山天池火山 岩浆囊 密度模型 重力剖面 人机交互解释 

分 类 号：P317[天文地球—固体地球物理学]