青海玉树<i>M</i><sub>S</sub>7.1地震发震过程的数值模拟

王连捷; 崔军文; 王薇; 乔子江; 孙东生; 赵卫华

青海玉树M_S7.1地震发震过程的数值模拟

1.
中国地质科学院地质力学研究所, 北京 100081
2.
中国地质科学院地质研究所, 北京 100037

基金项目:

国家“973”项目 2008CB425702

国土资源部深部探测技术与试验研究专项 SinoProbe-07

详细信息

作者简介:
王连捷(1933-), 男, 研究员, 从事地质灾害、地应力测量、应力场数值分析及应用研究。E-mail: wanglj01@sina.com

中图分类号: P315.01
计量
- 文章访问数: 198
- HTML全文浏览量: 103
- PDF下载量: 11
- 被引次数: 0
出版历程
- 收稿日期: 2010-05-25
- 刊出日期: 2010-06-01

NUMERICAL MODELING FOR MECHANISM OF YUSHU M_S7.1 EARTHQUAKE

1.
Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, China
2.
Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China

摘要

摘要: 根据玉树地区的地应力场、速度场和断层展布, 对青海玉树2010年4月14日M_S7.1级地震发震机理进行了数值模拟。将围岩看成弹性体, 断层看成具有应变软化的弹塑性体, 断层和围岩组成统一的地质介质系统。在地应力、孔隙压力及边界位移的作用下, 应力逐渐积累, 当达到断层摩擦破坏强度时, 断层产生应变软化, 断层突然滑动, 能量突然释放, 应力突然下降, 形成地震。模拟结果表明:玉树7.1级地震是在印度板块向北推挤, 青藏高原向东南侧向挤压, 在玉树地区形成主压应力为北东80°方向的水平应力场, 使甘孜-玉树断裂带产生左旋走滑错动形成的。计算结果给出了应力降、能量释放量、断层走滑错动量、地震复发周期、应力积累速度等重要参数, 模拟结果与野外调查资料具有较好的一致性。
- 玉树地震 /
- 地震数值模拟 /
- 应变软化模型 /
- 地震非稳定模型
Abstract: In this paper, strain softening model is used to establish the modeling for Yushu M_S7.1 earthquake. The results shows that Yushu M_S7.1 earthquake occurred as a combination of northward compressing of the Indian Plate and southeastward compressing of the Qinghai-Tibet Plateau. The stress drop, energy release amount, the magnitude of dislocation of fault, and earthquake recurrence intervals are given by the modeling. The modeling results show a good match with the geologic survey in the field.
- Yushu earthquake /
- earthquake modeling: strain-softening model /
- unsteady model of earthquake /

HTML全文

图 1 玉树及周边地区的应力场

Figure 1. Stress field around the Yushu area

下载: 全尺寸图片幻灯片

图 2 玉树地震区及周边地区GPS速度场

(据赖锡安等^[19])

Figure 2. Velocity field by GPS around the Yushu area

下载: 全尺寸图片幻灯片

图 3 计算模型

a-模型的平面图; b-模型的三维图; D-模型宽度; L-模型长度; H-模型深度; σ_H-最大水平主应力; σ_h-最小水平主应力; v-速度; p-孔隙压力

Figure 3. Model for calculationa

下载: 全尺寸图片幻灯片

图 4 模型网格(红线为断层面)

Figure 4. Mesh of model(red is fault plane)

下载: 全尺寸图片幻灯片

图 5 地震时断层的突然走向滑动(监测点为图 8 a点)

Figure 5. Sudden sliding of faultwhen the earthquake happened

下载: 全尺寸图片幻灯片

图 6 地震时的能量释放

Figure 6. Energy density curvewhen the earthquake happened

下载: 全尺寸图片幻灯片

图 7 地震应力降

Figure 7. Stress drop for the earthquake

下载: 全尺寸图片幻灯片

图 8 地震引起的沿断层走向的位移/m

(a点为位移监测点)

Figure 8. Fault displacement along strike caused by the earthquake

下载: 全尺寸图片幻灯片

图 9 断层两侧位移分布

Figure 9. The displacements on both sides of fault

下载: 全尺寸图片幻灯片

表 1 断层和围岩参数

Table 1. Parameters of fault and surroundings

参考文献(25)

[1]	谭成轩, 孙叶, 吴树仁, 等."5.12"汶川M_S 8.0大地震后关于我国区域地壳稳定性评价的思考[J].地质力学学报, 2009, 15(2):142~150. doi: 10.3969/j.issn.1006-6616.2009.02.004 TAN Cheng-xuan, SUN Ye, WU Shu-ren, et al.A consideration on regional crustal stability assessment after M_S 8.0 Wenchuan strong earthquake in China[J].Journal of Geomechanics, 2009, 15(2):142~150. doi: 10.3969/j.issn.1006-6616.2009.02.004
[2]	姚鑫, 张永双.基于差分干涉雷达的汶川地震同震形变特点[J].地质力学学报, 2009, 15(2):151~161. doi: 10.3969/j.issn.1006-6616.2009.02.005 YAO Xin, ZHANG Yong-shuang.Co-seismic deformation of 5.12 Wenchuan earthquake based on D-INSAR[J].Journal of Geomechanics, 2009, 15(2):151~161. doi: 10.3969/j.issn.1006-6616.2009.02.005
[3]	张永双, 石菊松, 孙萍, 等.汶川地震内外动力耦合及灾害实测[J].地质力学学报, 2009, 15(2):131~141. doi: 10.3969/j.issn.1006-6616.2009.02.003 ZHANG Yong-shuang, SHI Ju-song, SUN Ping, et al.Coupling between endogenic and exogenic geological processes in the Wenchuan earthquake and example analysis of geo-hazards[J].Journal of Geomechanics, 2009, 15(2):131~141. doi: 10.3969/j.issn.1006-6616.2009.02.003
[4]	张永双, 雷伟志, 石菊松, 等.四川5.12地震次生地质灾害的基本特征初析[J].地质力学学报, 2008, 14(2):109~116. doi: 10.3969/j.issn.1006-6616.2008.02.002 ZHANG Yong-shuang, LEI Wei-zhi, SHI Ju-song, et al.General characteristics of 5.12 earthquake-induced geo-hazards in Sichuan[J].Journal of Geomechanics, 2008, 14(2):109~116. doi: 10.3969/j.issn.1006-6616.2008.02.002
[5]	王连捷, 崔军文, 周春景, 等.汶川5.12地震发震机理的数值模拟[J].地质力学学报, 2009, 15(2):105~113. doi: 10.3969/j.issn.1006-6616.2009.02.001 WANG Lian-jie, CUI Jun-wen, ZHOU Chun-jing, et al.Numerical modeling for Wenchuan earthquake mechanism[J].Journal of Geomechanics, 2009, 15(2):105~113. doi: 10.3969/j.issn.1006-6616.2009.02.001
[6]	王连捷, 周春景, 孙东升, 等.汶川5.12地震引起的库仑变化及其对周边地震活动的影响[J].地质力学学报, 2008, 14(3):193~200. doi: 10.3969/j.issn.1006-6616.2008.03.001 WANG Lian-jie, ZHOU Chun-jing, SUN Dong-sheng, et al.Coulomb stress changes caused by Wenchuan earthquake and its influence on seismic activity in the adjacent area[J].Journal of Geomechanics, 2008, 14(3):193~200. doi: 10.3969/j.issn.1006-6616.2008.03.001
[7]	彭华, 马秀敏, 姜景捷, 等.龙门山北端青川断裂附近应力测量与断层稳定性[J].地质力学学报, 2009, 15(2):114~130. doi: 10.3969/j.issn.1006-6616.2009.02.002 PENG Hua, MA Xiu-min, JIANG Jing-jie.Stability and stress measurement near the Qingchuan fault in the northern Longmen Mountains[J].Journal of Geomechanics, 2009, 15(2):114~130. doi: 10.3969/j.issn.1006-6616.2009.02.002
[8]	彭华, 马秀敏, 姜景捷, 等.山丹地应力监测站应变仪的地震效应[J].地质力学学报, 2008, 14(2):97~108. doi: 10.3969/j.issn.1006-6616.2008.02.001 PENG Hua, MA Xiu-min, JIANG Jing-jie.Analysis of the volume strain data from the Shandan in-situ stress Monitoring Station[J].Journal of Geomechanics, 2008, 14(2):97~108. doi: 10.3969/j.issn.1006-6616.2008.02.001
[9]	马寅生, 张永双, 胡道功, 等.玉树地震地表破裂与宏观震中[J].地质力学学报, 2010, 16(2):115~124. doi: 10.3969/j.issn.1006-6616.2010.02.002 MA Yin-sheng, ZHANG Yong-shuang, HU Dao-gong.et al.The Surface Ruptures And The Macroscopical Epicenter Of Yushu M_S 7.1 Earthquake[J].Journal of Geomechanics, 2010, 16(2):115~124. doi: 10.3969/j.issn.1006-6616.2010.02.002
[10]	姚鑫, 张永双, 杨农, 等.玉树地震地表变形观测及初步分析[J].地质力学学报, 2010, 16(2):129~136. doi: 10.3969/j.issn.1006-6616.2010.02.003 YAO Xin, ZHANG Yong-shuang, YANG Nong, et al.D-InSAR Deformation Observation and Preliminary Analysis of the M_S 7.1 Yushu Earthquake[J].Journal of Geomechanics, 2010, 16(2):129~136. doi: 10.3969/j.issn.1006-6616.2010.02.003
[11]	张永, 许力生, 陈运泰. 2010年4月14日青海玉树M_S 7. 1级地震[EB/OL]. http://www.cea-igp.ac.cn/近期显著地震研究/标题. htm, 2010-04-17. ZHANG Yong, XU Li-sheng, CHEN Yun-tai. M_S 7. 1 earthquake in Yushu of Qinghai Province on April 12 th 2010[EB/OL]. http://www.cea-igp.ac.cn/, 2010-04-17
[12]	马寅生, 张永双, 胡道功. 地质力学研究所专家组青海玉树地震断裂调查[EB/OL]. http://www.geomech.ac.cn/xinwen/2010/yushudizhen/yushu0417.htm, 2010-04-17. MA Yin-sheng, ZHANG Yong-shuang, HU Dao-gong. Experts from Institute of Geomechanics investigated earthquake faults in Yushu, Qinghai Province[EB/OL]. http://www.geomech.ac.cn/xinwen/2010/yushudizhen/yushu0417.htm, 2010-04-17.
[13]	陈颙, 地壳岩石的力学性能[M].北京:地震出版社, 1988. CHEN Yong.Mechanical properties of Crustal rocks[M].Beijing:Seismological Publishing House, 1988.
[14]	J C耶格, N G W库克. 岩石力学基础[M]. 中国科学院工程力学研究所(译), 北京: 地震出版, 1981. Jaeger J C, Cook N G W. Basis of rock mechanics[M]. Institute of engineering mechanics, Chinese Academy of Science, (Trans. ). Beijing: Seismological Publishing House, 1981.
[15]	Rice J R.Theory of precursory processes in the inception of earthquake rupture[J].Gerlands Beitraege Fuer Geophysik, 1979, 88, 91~127. https://www.researchgate.net/publication/220010732_Theory_of_precursory_process_in_the_inception_of_earthquake_rupture
[16]	谭成轩, 马秀敏, 杨农, 等. 地质力学研究所地应力监测台站获得青海玉树M_S 7. 1级地震信息[EB/OL]. http://www.geomech.ac.cn/xinwen/2010/yushudizhen/yushujianbao.htm, 2010-04-15 TAN Cheng-xuan, MA Xiu-min, YANG Nong, et al. Information of M_S 7. 1 earthquake in Yushu of Qinghai Province was captured by the monitor station of crustal stress from the Institute of Geomechanics[EB/OL]. http://www.geomech.ac.cn/xinwen/2010/yushudizhen/yushujianbao.htm, 2010-04-15
[17]	美国地调局. Magnitude 6. 9-Southern Qinghai, China[EB/OL]. http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/us2010vacp.php, 2010-04-13. U S Geological Survey. Magnitude 6. 9-Southern Qinghai, China[EB/OL]. http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/us2010vacp.php, 2010-04-13.
[18]	彭华, 马秀敏, 李金锁, 等.南水北调西线一期工程地壳稳定性研究[M].北京:地震出版社, 2009. PENG Hua, MA Xiu-min, LI Jin-suo, et al.Study on crustal stability of West Route of South-to-North Water Transfer Project[M].Beijing:Seismological Publishing House, 2009.
[19]	赖锡安, 黄立文, 徐菊生, 等.中国大陆现今地壳运动[M].北京:地震出版社, 2004. LAI Xi-an, HUANG Li-wen, XU Ju-sheng, et al.Present crustal movement in China[M].Beijing:Seismological Publishing House, 2004.
[20]	Goodman R E, Taylor R L, Brekke T L.A model for the mechanics of jointed rock[J].Journal of Soil Mech.Found.Div., ASCE, 1968, 94(SM3):637~659. http://d.old.wanfangdata.com.cn/Periodical/zgkydxxb201106009
[21]	Zienkiewicz O C, Taylor R L.The finite element method (Fifth Edition), Volume 1:The basis, Volume 2:Solid mechanics, Volume 3:Fluid dynamics, Oxford:Butterworth-Heineman, 2000.
[22]	殷有泉, 张宏.模拟地震的应变软化的数学模型[J].地球物理学报, 1982, 25(5):414~423. doi: 10.3321/j.issn:0001-5733.1982.05.004 YIN You-quan, ZHANG Hong.A mathematical model of strain softening in simulating earthquake[J].Chinese Journal of Sinica, 1982, 25(5):414~423. doi: 10.3321/j.issn:0001-5733.1982.05.004
[23]	殷有泉, 张宏.断裂带内介质的软化特性和地震的非稳定模型[J].地震学报, 1984, 6(2):135~145. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=QK000000375734 YIN You-quan, ZHANG Hong.The softening behavior of fault zone medium and an instability model of earthquakes[J].Acta Seismologica Sinica, 1984, 6(2):135~145. http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=QK000000375734
[24]	殷有泉.非线性有限元基础[M].北京:北京大学出版社, 2007. YIN You-quan.Nonlinear finite element basis[M].Beijing:Peking University Press, 2007.
[25]	Stuart W D.Quasi-static earthquake mechanics[J].Reviews of Geophysics and Space Physics, 1979, (17):115~1120. http://d.old.wanfangdata.com.cn/Periodical/ytlx201012023