中国数字地震台网记录的昆仑山口西地震的球型自由振荡

地震 ›› 2005, Vol. 25 ›› Issue (1): 31-40.

中国数字地震台网记录的昆仑山口西地震的球型自由振荡

万永革^1,2, 周公威³, 郭燕平³

1.防灾技术高等专科学校, 北京 101601;
2.中国地震局地质研究所, 北京 100029;
3.中国地震局地球物理研究所, 北京 100081

收稿日期:2004-05-31 修回日期:2004-09-09 出版日期:2005-01-31 发布日期:2021-11-10
作者简介:万永革(1967-), 男, 河北馆陶人, 副研究员, 2001年获博士学位, 主要从事地震学及地球动力学等研究。
基金资助:
国家重点基础研究发展规划项目(2001CB711005)资助

Spherical mode of the earth free oscillation excitated by the earthquake in the west to the Kunlun mountain pass recorded by China digital seismograph network

WAN Yong-ge^1,2, ZHOU Gong-wei³, GUO Yan-ping³

1. College of Disaster Prevention Techniques, Yanjiao, East of Beijing 101601;
2. Institute of Geology, CEA, Beijing 100029;
3. Institute of Geophysics, Beijing 100081, China

Received:2004-05-31 Revised:2004-09-09 Online:2005-01-31 Published:2021-11-10

摘要/Abstract

摘要： 利用中国数字地震台网 (CDSN)改造后的7个台站的VHZ波形资料, 采用功率谱密度估计方法, 利用中国数字地震台网地震仪对低频信号压制的特点, 在没有对资料去除固体潮影响的情况下, 提取了2001年11月14日昆仑山口西地震激发的₀S₄~₀S₇₆地球球型自由振荡, 并与地球初步参考模型(PREM)的理论自由振荡周期进行对比, 结果表明与PREM预测的球型自由振荡周期符合得很好。该地震的地球自由振荡信息, 可用于地震震源机制研究和地球内部结构研究。

关键词: 中国数字地震台网, 昆仑山口西地震, 地球自由振荡, 球型振荡

Abstract: Based on VHZ data recorded by 7 stations of China digital seismograph network (CDSN) for Nov. 14, 2001, earthquake in the west of the Kunlun mountain pass, we extracted spherical mode of ₀S₄~₀S₇₆ of the earth free oscillation using power spectral density (PSD) estimation. Because the frequency response of seismograph in China digital seismograph network suppress information of solid tide, we do not need to remove the solid tide in our procession. Our result is nearly consistent with frequency of the modes of preliminary reference earth model (PREM). The data of the earth spherical free oscillation can be used to invert focal mechanism of this earthquake and to explore the inner structure of the earth.

Key words: China digital seismograph network, Earthquake in the west of the Kunlun mountain pass, Power spectral density estimation, Spherical free oscillation of the earth

中图分类号:

P315.61

万永革, 周公威, 郭燕平. 中国数字地震台网记录的昆仑山口西地震的球型自由振荡[J]. 地震, 2005, 25(1): 31-40.

WAN Yong-ge, ZHOU Gong-wei, GUO Yan-ping. Spherical mode of the earth free oscillation excitated by the earthquake in the west to the Kunlun mountain pass recorded by China digital seismograph network[J]. EARTHQUAKE, 2005, 25(1): 31-40.

参考文献

[1] 傅承义, 陈运泰, 祁贵仲. 地球物理学基础[M]. 北京: 地震出版社, 1985. 347-368.
[2] Lamb H. On the variations of an elastic sphere[J]. Lond Math Soc Proc, 1882, 13: 233-256.
[3] Love A E H. Some problems of geodynamics[M]. Cambridge: Cambridge University Press, 1911.
[4] Benioff H, Press F, Smith S. Excitation of the free oscillations of the earth by earthquakes[J]. J Geophys Res, 1961, 66: 605-619.
[5] Ness N R, Harrison C T, Slichter L B. Observation of the free oscillation of the earth[J]. J Geophys Res, 1961, 66: 621-629.
[6] Derr J S. Internal structure of the earth inferred from free oscillations[J]. J Geophys Res, 1969, 74: 5202-5219.
[7] Haddon R A W, Bullen K E. An earth model incorporating free oscillation data[J]. Phys Earth Planet Inter, 1969, 2: 35-49.
[8] Dziewonski A M, Anderson D L. Preliminary reference Earth model (PREM)[J]. Phys Earth Planet Inter, 1981, 25: 297-356.
[9] Shibata N, Suda N, Fukao Y. Use of apparent complex frequencies of free oscillations to estimate aspherical structure of the Earth[J]. Geophys Res Lett, 1991, 18: 905-908.
[10] Resovsky J S, Pestana R. Improved normal mode constraints on lower mantle Vp from generalized spectral fitting[J]. Geophys Res Lett, 2003, 30: 1-4.
[11] Kedar S, Watada S, Tanimoto T. The 1989 Macquarie Ridge earthquake: Seismic moment estimation from long period free oscillations[J]. J Geophys Res, 1994, 99: 17893-17908.
[12] 马淑田, 郝建国. 1995年7月12日中缅边界M_S=7.3地震的震源机制解[J]. 地震学报, 1997, 19(1): 107-109.
[13] 高原, Van Der Lee S, Giardini D, 等. 应用振型叠加方法研究1997年11月8日中国西藏玛尼地震震源机制[J]. 地球物理学报, 2001, 44(增刊): 98-106.
[14] Courtier N, Ducarme B, Goodkind J, et al. Global superconducting gravimeter observations and the search for the translational modes of the inner core[J]. Phys Earth Planet Inter, 2000, 117: 3-20.
[15] Beroza G C, Jordan T H. Searching for slow and silent earthquakes using free oscillations[J]. J Geophys Res, 1990, 95: 2485-2510.
[16] Van Camp M. Measuring seismic normal modes with the GWRC021 superconducting gravimeter[J]. Phys Earth Planet Inter, 1999, 116: 81-92.
[17] 雷湘鄂, 许厚泽, 孙和平. 利用超导重力观测资料检测地球自由振荡[J]. 科学通报, 2002, 47(18): 1432-1436.
[18] 吕永清, 蔡亚先, 周云耀. 用JCZ-1超宽频带数字地震仪观测地球自由振荡[J]. 地壳形变与地震, 1997, 17(3): 103-105.
[19] Lin A, Fu B, Guo J, et al. Co-seismic strike-slip and rupture length produced by the 2001 M_S8.1 central Kunlun earthquake[J]. Science, 2002, 296: 2015-2017.
[20] Xu X, Chen W, Ma W, et al. Surface rupture of the Kunlunshan earthquake (M_S8.1)[J]. Northern Tibetan Plateau China, Seism Res Lett, 2002, 73: 884-892.
[21] 陈杰, 陈宇坤, 丁国瑜, 等. 2001年昆仑山口西8.1级地震地表破裂带[J]. 第四纪研究, 2003, 23(6): 629-639.
[22] Nowroozi A A. Characteristic periods of fundamental and overtone oscillations of the earth following a deep-focus earthquake[J]. Bull Seism Soc Amer, 1972, 62: 247-274.
[23] Nishida K, Kobayashi N. Statistical features of Earth′s continuous free oscillations[J]. J Geophys Res, 1999, 104: 28741-28750.
[24] Tanimota T, Um J, Nishida K, et al. Earth′s continuous oscillations observed on seismically quiet days[J]. Geophys Res Lett, 1998, 25: 1553-1556.
[25] Tanimota T, Um J. Cause of continuous oscillations of the Earth[J]. J Geophys Res, 1999, 104: 28723-28740.
[26] Widmer-Schnidrig R. Free oscillations illuminate the mantle[J]. Nature, 1999, 398: 292-293.
[27] Resovsky J S, Ritzwoller M H. New and refined constraints on three-dimensional Earth structure from normal modes below 3 mHz[J]. J Geophys Res, 1998, 103: 783-810.
[28] Resovsky J S, Ritzwoller M H. A degree 8 mantle shear velocity model from normal mode observations below 3 mHz[J]. J Geophys Res, 1999, 104: 993-1014.