2015 NEPAL EARTHQUAKE AND THE FUTURE SEISMIC TREND OF HIMALAYA OROGENIC BELT
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摘要: 2015年4月25日尼泊尔Ms 8.1级大地震是发生在喜马拉雅造山带中段的低角度逆冲断层运动, 特点是震源很浅, 震中烈度达Ⅺ度, 震害严重。破裂带走向北西西—南东东, 穿越尼泊尔首都加德满都, 使首都建筑遭受严重破坏。该震是1934年以来尼泊尔最大地震, 标志着喜马拉雅带自1950年以来半个世纪的平静期已经结束。自2005年进入新活动期, 至2015年尼泊尔大地震发生已达到活动高潮。预计将持续十到几十年。根据历史地震资料分析, 今后可能沿喜马拉雅带走向发生纵向迁移, 将在喜马拉雅带东段发生更大的地震, 从而使地震高潮达到顶峰而结束, 可能对我国西藏东南、不丹和印度边界产生破坏。另外还可能沿着与喜马拉雅带走向垂直方向向北迁移(即横向迁移), 在几年之内即可在西藏、青海引起破坏性地震, 需要相关省市做好监测预报和防灾工作。Abstract: This paper briefly introduces the parameters of the M 8.1 earthquake on April 25, 2015, which is a low angle thrust fault movement in the middle of the Himalaya orogenic belt. The characteristics is that the source is very shallow, the intensity of the earthquake reaches to Ⅺ degree and the earthquake damage is severe. The rupture zone have a strike of the North West-South East, crossing the Nepalese capital Kathmandu, where the construction suffered serious damage. The earthquake was the largest earthquake in Nepal since 1934, which marking the end of the period of peace in Himalaya since 1950. Since entering the new active period in 2005, the great earthquake occurred in Nepal has reached the climax of the event in 2015, which is expected to last ten to several decades. According to the analysis of data of historical earthquakes, it may have a migration along the Himalayan zone in the future, and there will be larger earthquake in the eastern part of the Himalayan belt, so as to reach the top of earthquake tide and then have a end. There may be serious damage to the border of India, Bhutan and east-south region of Tibet. It is also possible to move northwardly along with the Himalaya belt in the vertical direction (i.e. horizontal migration), causing destructive earthquakes in Tibet, Qinghai in a few years. It needs to do a good job in monitoring, forecasting, and disaster prevention.
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Key words:
- earthquake climax /
- earthquake migration /
- seismic trend
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图 2 喜马拉雅弧地震应变释放曲线及M≥7.0地震序列(1800—2014)
Figure 2. Strain release curve and M≥7 earthquake sequence of Himalaya arc (1800—2014)
图 3 喜马拉雅弧地震时空图像(M≥7.5)(斜线阴影部分表示空区范围，据文献[6]修改)
Figure 3. Spatio-temporal image (M≥7.5) of earthquake in Himalaya arc
图 4 喜马拉雅带地震纵向迁移图示(M≥7.5)
Figure 4. Earthquakes migration along the Himalaya belt (M≥7.5)
图 5 喜马拉雅带地震横向迁移示意图(箭头表示地震形变波传播方向)
Figure 5. Schematic diagram of seismic lateral migration in Himalaya belt
表 1 喜马拉雅带地震横向迁移数据
Table 1. Table of seismic lateral migration in Himalaya belt
发震时间 震中 震级 发震地点 持续时间/a 迁移速度/
(km·a-1)备注 N E 1934-01-15 26.5 86.5 8.1 尼泊尔 1934-12-15 31.1 88.8 7.0 西藏申扎 3 550 高速迁移 1937-01-07 35.5 97.6 6.5 青海阿拉克湖 1949-02-23 41.9 83.2 7.2 库车(新疆) 23 70 中速迁移 1957-12-04 45.1 99.4 8.1 蒙古 1951-11-18 31.1 91.4 8.0 当雄 57 20 低速迁移 1973-07-14 35.1 86.5 7.3 尼玛 1991-02-15 40.0 79.0 6.5 林平(新) 1950-08-15 28.5 96.7 8.6 察隅 1951-11-18 31.1 91.4 8.0 当雄 2 550 高速迁移 1952-10-05 37.1 93.2 6.0 玛格美仁(青海) 1962-05-21 36.9 95.8 6.9 格尔木(青海) 24 70 中速迁移 1970-06-05 42.2 78.7 6.6 阿拉木图 1974-07-04 45.0 93.9 7.5 蒙古 1971-04-03 32.0 95.0 6.5 杂多 51 18 低速迁移 2001-11-14 36.2 90.9 8.1 昆仑山 
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[1] USGS. Poster of the Nepal Earthquake of 25 April 2015-Magnitude 7[EP/OL]. http://earthquake.usgs.gov/earthquakes/eqarchives/poster/2015/20150425.php. [2] 中国地震信息网. 2015尼泊尔8. 1级地震, 全球震源机制解[EP/OL]. http://www.csi.ac.cn/manage/eqDown/13Fault_xiguapi/201504.htm.China Earthquake Information Network. 2015 Nepal 8.1 earthquake, the global focal mechanism solution[EP/OL]. http://www.csi.ac.cn/manage/eqDown/13Fault_xiguapi/201504.htm. [3] Chandra U. Seismicity, earthquake mechanisms and tectonics along the Hmalayan Mountain range and vicinity[J]. Physics of the Earth and Planetary Interiors, 1978, 16(2): 109~131. doi: 10.1016/0031-9201(78)90083-3 [4] Bilham R, Gaur V K, Molnar P. Himalayan seismic hazard[J]. Science, 2001, 293: 1442~1444. doi: 10.1126/science.1062584 [5] EMSC-CSEM, 2015 M 7.8 NEPAL on April 25th 2015 at 06:11 UTC[EP/OL]. http://www.emsc-csem.org/Earthquake/233/M7-8-NEPAL-on-April-25th-2015-at-06-11-UTC. [6] Thakur V C, Jayangondaperumal R, Malik M A. Redefining Medlicott-Wadia's main boundary fault from Jhelum to Yamuna: An active fault strand of the main boundary thrust in northwest Himalaya[J]. Tectonophysics, 2010, 489(1/4): 29~42. https://www.sciencedirect.com/science/article/pii/S0040195110001368 [7] 赵根模, 姚兰予, 马淑芹.断层位错引起的应力场变动与地震危险性预测[J].地震学报, 1994, 16(4):448~454. http://www.cnki.com.cn/Article/CJFDTOTAL-DZXB404.005.htmZHAO Gen-mo, YAO Lan-yu, MA Shu-qin. Stress field variation caused by fault dislocation and seismic hazard prediction [J]. Acta Seismologica Sinica, 1994, 16(4): 448~454. http://www.cnki.com.cn/Article/CJFDTOTAL-DZXB404.005.htm [8] 刘艳辉, 赵根模, 吴中海, 等.地震空区法在大地震危险性初判中的应用——以青藏高原东南缘为例[J].地质力学学报, 2014, 20(3):254~273. http://journal.geomech.ac.cn/ch/reader/view_abstract.aspx?flag=1&file_no=20140305&journal_id=dzlxxbLIU Yan-hui, ZHAO Gen-mo, WU Zhong-hai, et al. Application of spatial database technology and seismic gap method to seismic hazard analysis around south-eastern Tibetan Plateau [J]. Journal of Geomechanics, 2014, 20(3): 254~273. http://journal.geomech.ac.cn/ch/reader/view_abstract.aspx?flag=1&file_no=20140305&journal_id=dzlxxb [9] 刘艳辉, 赵根模, 吴中海, 等.青藏高原东南缘及邻区近年来地震b值特征[J].地质通报, 2015, 34(1):58~70. http://d.wanfangdata.com.cn/Periodical/zgqydz201501005LIU Yan-hui, ZHAO Gen-mo, WU Zhong-hai, et al. An analysis of b-value characteristics of earthquake on the southeastern margin of the Tibetan Plateau and its neighboring areas[J]. Geological Bulletin of China, 2015, 34(1): 58~70. http://d.wanfangdata.com.cn/Periodical/zgqydz201501005 [10] 吴中海, 赵根模, 龙长兴, 等.青藏高原东南缘现今大震活动特征及其趋势:活动构造体系角度的初步分析结果[J].地质学报, 2014, 88(8):1401~1416. http://www.cnki.com.cn/Article/CJFDTOTAL-DZXE201408004.htmWU Zhong-hai, ZHAO Gen-mo, LONG Chang-xing, et al. The seismic hazard assessment around South-East area of Qinghai-Xizang Plateau: A preliminary results from active tectonics system analysis[J]. Acta Geologica Sinica, 2014, 88(8): 1401~1416. http://www.cnki.com.cn/Article/CJFDTOTAL-DZXE201408004.htm -
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