云南鲁甸M_S6.5地震震区地壳密度结构特征
详细信息 本馆镜像全文    |  推荐本文 | | 获取馆网全文
摘要
基于云南鲁甸MS6.5地震震区的3条"工"字形剖面的重力与GPS观测数据,获得了沿剖面的布格重力异常、剩余密度相关成像和地壳密度分层结构。研究表明,会理—鲁甸—昭通、攀枝花—蒙姑—大井、舍块—汤丹—会泽剖面布格重力变化范围分别为-278~-197×10-5ms-2、-273~-200×10-5ms-2、-280~-254×10-5ms-2,均呈"鞍"形分布,其局部低值均位于小江断裂带附近,且幅度差自北向南逐渐减小。小江断裂带内物质密度低于两侧,低密度体扩展至中下地壳,且其东侧物质密度低于西侧,密度异常体呈正负交迭,地壳稳定性低,鲁甸震区处于该区域内。地壳分层结构显示莫霍面以小江断裂带为中心向上抬升,莫霍面最大深度自北向南从50km抬升至41km,反映了小江断裂带在区域地质构造中的地位——川滇块体与华南块体的分界线。
In this paper,based on three gravity profiles in Yunnan Ludian MS6. 5 earthquake and adjacent area, we obtained Bouguer gravity anomaly, residual density correlation image and crustal stratification structure along the profiles. The study shows a saddle-shaped distribution of Bouguer gravity anomalies along the Huili-Ludian-Zhaotong, Panzhihua- Menggu- Dajing and Shekuai-Tangdan- Huize profile,with the values ranging- 278 ~- 197 × 10 ~ 5ms- 2,- 273 ~- 200 × 10~ 5ms- 2,- 280 ~- 254 × 10 ~ 5ms- 2,respectively; the local low values locate in the Xiaojiang fault zone,the amplitude difference decreases gradually from the north to the south; the density in the Xiaojiang fault zone is lower than that of the sides,the low density zone extends to the middle and lower crust,and the material density in the east is lower than that in the west; positive and negative density anomalies overlap,indicating a poor stability of the lower crust. The Ludian earthquake occurred in this region. Layered crustal structure shows the undulation of Moho surface,with uplift beneath the Xiaojiang fault zone as the center and change of the maximum depth of Moho from 50 km up to 41 km from north to south. This reflects the position of Xiaojiang Fault in the regional geological structure as block boundary of Sichuan-Yunnan block and South China block.
引文
陈石,王青华,王谦身,等.2014.云南鲁甸MS6.5地震震源区和周边三维密度结构及重力场变化[J].地球物理学报,57(9):3080—3090.CHEN Shi,WANG Qing-hua,WANG Qian-shen,et al.2014.The 3D density structure and gravity change of LudianMS6.5 Yunnan epicenter and surrounding regions[J].Chinese J Geophys,57(9):3080—3090(in Chinese).
    房立华,吴建平,王未来,等.2014.云南鲁甸MS6.5地震余震重定位及其发震构造[J].地震地质,36(4):1173—1185.doi:10.3969/j.issn.0253-4967.2014.04.019.FANG Li-hua,WU Jian-ping,WANG Wei-lai,et al.2014.Relocation of the aftershock sequence of the MS6.5 Ludianearthquake and its seismogenic structure[J].Seismology and Geology,36(4):1173—1185(in Chinese).
    郭良辉,孟小红,石磊,等.2009.重力和重力梯度数据三维相关成像[J].地球物理学报,52(4):1098—1106.doi:10.3969/j.issn.0001-5733.2009.04.027.GUO Liang-hui,MENG Xiao-hong,SHI Lei,et al.2009.3-D correlation imaging for gravity and gravity gradiometrydata[J].Chinese Journal Geophysics,52(4):1098—1106(in chinese).
    何宏林,池田安隆,何玉林,等.2008.新生的大凉山断裂带:鲜水河-小江断裂系中段的裁弯取直[J].中国科学(D辑),51(9):1248—1258.HE Hong-lin,IKEDA Yasutaka,HE Yu-lin,et al.2008.Newly generated Daliangshan Fault zone:Shortcutting onthe central section of Xianshuihe-Xiaojiang fault system[J].Science in China(Ser D),51(9):1248—1258(in Chinese).
    何正勤,叶太兰,苏伟.2004.云南地区地壳中上部横波速度结构研究[J].地球物理学报,47(5):838—844.HE Zheng-qin,YE Tai-lan,SU Wei.2004.S-wave velocity structure of the middle and upper crust in the Yunnanregion[J].Chinese J Geophys,47(5):838—844(in Chinese).
    李永华,吴庆举,田小波,等.2009.用接收函数方法研究云南及其邻区地壳上地幔结构[J].地球物理学报,52(1):67—80.LI Yong-hua,WU Qing-ju,TIAN Xiao-bo,et al.2009.Crustal structure in the Yunnan region determined bymodeling receiver functions[J].Chinese J Geophys,52(1):67—80(in Chinese).
    魏文薪,江在森,武艳强,等.2012.小江断裂带的运动及应变积累特征研究[J].大地测量与地球动力学,32(2):11—15.WEI Wen-xin,JIANG Zai-sen,WU Yan-qiang,et al.2012.Study on motion characteristics and strain accumulationof Xiaojiang Fault zone[J].Journal of Geodesy and Geodynamics,32(2):11—15(in Chinese).
    闻学泽,杜方,龙锋,等.2011.小江和曲江-石屏两断裂系统的构造动力学与强震序列的关联性[J].中国科学(D辑),41(5):713—724.WEN Xue-ze,DU Fang,LONG Feng,et al.2011.Tectonic dynamics and correlation of major earthquake sequencesof the Xiaojiang and Qujiang-Shiping fault systems,Yunnan[J].Science in China(Ser D),41(5):713—724(in Chinese).
    吴建平,明跃红,王椿镛.2001.云南数字地震台站下方的S波速度结构研究[J].地球物理学报,44(2):228—238.WU Jian-ping,MING Yue-hong,WANG Chun-yong.2001.The S-wave velocity structure beneath digital seismicstations of Yunnan Province inferred from teleseismic receiver function modeling[J].Chinese J Geophys,44(2):228—238(in Chinese).
    熊绍柏,郑晔,尹周勋,等.1993.丽江-攀枝花-者海地带二维地壳结构及其构造意义[J].地球物理学报,36(4):434—444.XIONG Shao-bai,ZHENG Ye,YIN Zhou-xun,et al.1993.The 2-D structure and its tectonic implications of the crustin the Lijiang-Panzhihua-Zhehai region[J].Chinese Journal of Geophysics,36(4):434—444(in Chinese).
    徐涛,张明辉,田小波,等.2014.丽江-清镇剖面上地壳速度结构及其与鲁甸MS6.5地震孕震环境的关系[J].地球物理学报,57(9):3069—3079.XU Tao,ZHANG Ming-hui,TIAN Xiao-bo,et al.2014.Upper crustal velocity of Lijiang-Qingzhen profile and itsrelationship with the seismogenic environment of the MS6.5 Ludian earthquake[J].Chinese J Geophys,57(9):3069—3079(in Chinese).
    徐锡伟.2014.云南鲁甸6.5级地震发震断层分析[Z].http:∥www.eqigl.ac.cn/wwwroot/c_00000009 0001/d_1406.html.XU Xi-wei.2014.Analysis on the seismogenic fault of Yunnan Ludian 6.5 earthquake[Z].http:∥www.eqigl.ac.cn/wwwroot/c_00000009 0001/d_1406.html(in Chinese).
    徐锡伟,闻学泽,郑荣章,等.2003.川滇地壳活动块体最新构造变动样式及其动力来源[J].中国科学(D辑),33(增刊):151—162.XU Xi-wei,WEN Xue-ze,ZHENG Rong-zhang,et al.2003.Pattern of latest tectonic motion and its dynamics foractive blocks in Sichuan-Yunnan region,China[J].Science in China(Ser D),33(suppl):151—162(inChinese).
    张勇,许力生,陈运泰,等.2014.2014年8月3日云南鲁甸MW6.1(MS6.5)地震破裂过程[J].地球物理学报,57(9):3052—3059.ZHANG Yong,XU Li-sheng,CHEN Yun-tai,et al.2014.Rupture process of the 3 August 2014 Ludian,Yunnan,MW6.1(MS6.5)earthquake[J].Chinese J Geophys,57(9):3052—3059(in Chinese).
    张广伟,雷建设,梁姗姗,等.2014.2014年8月3日云南鲁甸MS6.5地震序列重定位与震源机制研究[J].地球物理学报,57(9):3018—3027.ZHANG Guang-wei,LEI Jian-she,LIANG Shan-shan,et al.2014.Relocations and focal mechanism solutions of the3 August 2014 Ludian,Yunnan MS6.5 earthquake sequence[J].Chinese J Geophys,57(9):3018—3027(inChinese).
    张培震,邓起东,张国民,等.2003.中国大陆强震活动与活动地块[J].中国科学(D辑),33(增刊):12—20.ZHANG Pei-zhen,DENG Qi-dong,ZHANG Guo-min,et al.2003.Strong earthquake activity and active crustal-blockin China mainland China[J].Science in China(Ser D),33(Suppl):12—20(in Chinese).
    Guangliang Yang,et al.2012.Estimating Moho basement and faults using gravity inversion in Yushu[J].Geodesyand Geodynamics,3(2):8—13.
    Talwani M,Sutton G H,Worzel J L.1959.A crustal section across the Puerto Rico Trench[J].J Geophys Res,64(10):1545—1555.

版权所有:© 2023 中国地质图书馆 中国地质调查局地学文献中心