兴蒙造山带阿尔山火山群地壳厚度与波速比研究  

Crustal thickness and vP/vS ratio of Arxan volcanic group in Xing’an-Mongolia orogenic belt

作　　者：张雅茜 吴庆举[1,2] 张瑞青[1,2] 白兰淑 Zhang Yaxi;Wu Qingju;Zhang Ruiqing;Bai Lanshu(Institute of Geophysics,China Earthquake Administration,Beijing 100081,China;Key Laboratory of Earthquake Source Physics,China Earthquake Administration,Beijing 100081,China)

机构地区：[1]中国地震局地球物理研究所,北京100081 [2]中国地震局震源物理重点实验室,北京100081

出　　处：《地震学报》2022年第6期949-960,共12页Acta Seismologica Sinica

基　　金：国家自然科学基金(41874112,41874073);中国地震局地球物理研究所基本科研业务费专项(DQJB19B26,DQJB20K28)联合资助.

摘　　要：利用架设在我国东北地区阿尔山火山区的宽频带流动地震台站记录的远震波形数据,采用P波接收函数H-κ叠加扫描方法,得到了阿尔山火山区的地壳厚度和平均波速比。结果显示:阿尔山地区的地壳厚度范围为33.9—37.9 km,整体呈西北厚东南薄的特点,火山带附近地壳较薄;地壳平均波速比范围为1.73—1.83,主要有柴河镇—明水河镇、伊敏德仁北部和天池镇三处高波速比区。结合前人研究结果推断,阿尔山火山区薄的地壳和高波速比值可能是由地幔物质上涌、玄武岩浆底侵下地壳所致。The Arxan volcanic group is one of the most important volcanic groups in the Quaternary in Northeast China.It is of great significance to obtain information of crustal structure and vP/vS ratios in this area for studying the physical properties of the crust and tectonic evolution beneath the volcanoes.Original waveform data came from temporary broadband seismic stations in the Arxan volcanic area.The crustal thickness and average vP/vS in the study area are obtained by the P-wave receiver function and H-κstacking method.The results show that the crust thickness is thicker in the northwest and thinner in the southeast,ranging from 33.9 km to 37.9 km,with thinner crust near the volcanic belt.There is a positive correlation between crustal thickness and elevation.The vP/vS ratio ranges from 1.73 to 1.83.There are three high vP/vS ratio areas in the study area:Chaihe town-Mingshuihe town,the north of Yimin Doren and Tianchi town.The thin crust and high wave velocity ratio areas beneath Arxan volcanic region may be caused by the upwelling of mantle material and underplating of basaltic magma.

关 键 词：阿尔山火山区 接收函数 H-κ叠加 地壳厚度 波速比 

分 类 号：P315.31[天文地球—地震学] P315.63[天文地球—固体地球物理学]