1974 Zhaotong earthquake

Earthquake in China 1974 Zhaotong earthquake 1974-05-10 19:25:16 748061 iscgem748061 1974 05 11 03:25:16 China#Yunnan 7.1 s y 14 km on 28.24 104.01 inline,title China, Yunnan, Sichuan 9 1,641–20,000 dead The 1974 Zhaotong earthquake occurred at 3:25 in the morning local time on 11 May 1974, with a Coordinated Universal Time (UTC) time of 19:25:16 on 10 May. It had a magnitude that was measured at 7.0 on the moment magnitude scale and 7.1 on the surface-wave magnitude scale. It had a maximum perceived intensity of IX (Violent) on the Mercalli intensity scale. The epicenter was located in Zhaotong prefecture in Yunnan province and it caused between 1,641 and 20,000 deaths. Earthquake The earthquake has been ascribed to slip on a thrust fault trending north–south with a dip of 60° to the east, from geodetic data analysis.Zhu C.-N. Chen C.-Z. 1976 The Rupture Mechanism of the Zhaotong earthquake of 1974 in Yunnan Province abstract only 19 4 Chinese Journal of Geophysics http://118.145.16.227/geophy/EN/abstract/abstract5531.shtml 17 July 2012 https://web.archive.org/web/20131212182104/http://118.145.16.227/geophy/EN/abstract/abstract5531.shtml 2013-12-12 dead It has also been interpreted to result from strike-slip faulting along a steeply-dipping NW-SE trending fault.Zhuo Y. Kanamori H. 1987 Regional variation of the short-period (1 to 10 second) source spectrum Bulletin of the Seismological Society of America 77 2 514–529 10.1785/BSSA0770020514 1987BuSSA..77..514Z http://mh-gps-p1.caltech.edu/uploads/File/People/kanamori/HKbssa87d.pdf 18 July 2012 https://web.archive.org/web/20131211213036/http://mh-gps-p1.caltech.edu/uploads/File/People/kanamori/HKbssa87d.pdf 2013-12-11 dead The isoseismal lines for the earthquake were poorly defined, due to variations both in topography and ground conditions. The earthquake consisted of more than ten separate sub-events. The sequence began with a few shocks in the first two to three seconds with magnitudes less than 5. These were followed by several shocks approaching magnitude 7 over a period of about a minute. The areal distribution of the individual shocks showed no progression along the fault plane as would be expected with a propagating fracture.Tseng J.S. Shi J.S. 1978 Source multiplicity of the main shock of the Yong Shan-Da Guan Yunnan Earthquake of May 10, 1974 Acta Geophysica Sinica 21 160–173 http://en.cnki.com.cn/Article_en/CJFDTOTAL-DQWX197802004.htm 18 July 2012 11 December 2013 https://web.archive.org/web/20131211212307/http://en.cnki.com.cn/Article_en/CJFDTOTAL-DQWX197802004.htm dead The earthquake triggered many landslides in the epicentral area. The bedrock geology in the area contains rocks of almost all ages from Neoproterozoic through to Quaternary. Landslides were mainly confined to areas that experienced intensities of VII or greater and had slopes of moderate dip (26°–45°). In all but one case, the landslides involved Quaternary material, the exception being a slide that was controlled by bedding planes in a Permian limestone. Rock avalanches occurred on steeper slopes, particularly affecting jointed and weathered Permian limestone and Triassic sandstone/shale sequences.Chen X.L. Zhou Q., Ran H. & Dong R. 2012 Earthquake-triggered landslides in southwest China Natural Hazards and Earth System Sciences 12 2 351–363 10.5194/nhess-12-351-2012 2012NHESS..12..351C free Damage An area of about 400,000 square kilometres was affected by the earthquake. 28,000 houses collapsed and a further 38,000 were damaged. Houses with wooden frames in the epicentral area remained undamaged.http://www.kepu.net.cn/english/quake/outline/otl05.html Earthquakes in China: Typical earthquakes Museum of Earthquakes Computer Network Information Center of Chinese Academy of Sciences 21 September 2013 The number of deaths reported varies from 1,641 to 20,000 with a further 1,600 injured. The largest landslide formed a dam up to 30 m high across the Yangtze River, turning the valley above it into a lake. See also List of earthquakes in 1974 List of earthquakes in Yunnan List of earthquakes in Sichuan List of earthquakes in China References Hu Y. Liu S.C. Liu Shaw-chen Dong W. Earthquake Engineering Taylor & Francis 1996 107–108 Earthquakes in China 9780419205906 https://books.google.com/books?id=suaVCkVdyuwC&pg=PA107 17 July 2012 http://www.ngdc.noaa.gov/nndc/struts/results?eq_0=4658&t=101650&s=13&d=22,26,13,12&nd=display https://web.archive.org/web/20170730023035/https://www.ngdc.noaa.gov/nndc/struts/results?eq_0=4658&t=101650&s=13&d=22,26,13,12&nd=display dead July 30, 2017 Comments for the Significant Earthquake National Geophysical Data Center National Geophysical Data Center 17 July 2012 International Handbook of Earthquake & Engineering Seismology Part A, Volume 81A A List of Deadly Earthquakes in the World: 1500–2000 T. R. Utsu 2002 Academic Press First 978-0124406520 708 External links 748061 Category:1974 earthquakes Category:1974 disasters in China Category:May 1974 in Asia Category:Earthquakes in Yunnan Category:Geography of Zhaotong Category:Earthquakes in Sichuan