China News Service, Chengdu, June 13 (Reporter Liu Zhongjun) The China Earthquake Administration officially released the earthquake intensity map of the M6.0 earthquake swarm in Aba Prefecture, Sichuan Province on the 13th. The highest intensity is VIII (8 degrees).
It is understood that the investigation and evaluation of earthquake intensity is the basis and basis for the response and disposal of earthquake events. The so-called seismic intensity, seismic intensity map and intensity evaluation reflect the degree of damage to the ground and buildings affected by the earthquake, including Destruction of buildings, changes in natural landscape, etc.
Earthquake intensity in my country is divided into 12 grades, the higher the grade, the heavier the damage.
After the Malkang earthquake, in accordance with the deployment of the Ministry of Emergency Management and the China Earthquake Administration, the Sichuan Earthquake Administration's 74-person on-site work team conducted a survey of 5 cities and counties including Malkang City, Hongyuan County, Aba County, Rangtang County and Jinchuan County in Aba Prefecture, 21 The earthquake disaster survey in each township and the earthquake disaster intensity assessment lasted for 4 days, with a journey of more than 15,000 kilometers. The disaster investigation team sent a total of 26 groups of 98 people to investigate a total of 77 sampling points, and obtained a large amount of basic data.
Combined with the instrumental intensity, referring to the aftershock distribution, focal mechanism solution, UAV remote sensing and other achievements, the intensity distribution of this earthquake was determined, and the "Sichuan Malkang 6.0" was compiled in accordance with the "Code for Mapping of Seismic Intensity Maps" (GB/T38266-2019). Earthquake intensity map of magnitude swarms.
On June 10, 2022, earthquakes of magnitude 5.8, 6.0, and 5.2 occurred successively in Malkang City, Sichuan, which belonged to a swarm type earthquake.
The earthquake intensity distribution of the earthquake swarm was formed by the superposition of the three earthquake damages. The highest intensity was Ⅷ degree (8 degrees). The long axis of the isoseismal line was NW trending, the long axis was 111 kilometers, the short axis was 67 kilometers, and the VI degree (6 degrees) ) district and above covers an area of 5,719 square kilometers, mainly involving Malkang City, Aba County, Hongyuan County and Rangtang County of Aba Tibetan and Qiang Autonomous Prefecture, a total of 4 counties (cities) and 21 townships, including 11 townships in Malkang City and Aba County. There are 5 townships in the county, 2 townships in Hongyuan County, and 3 townships in Rangtang County.
The VIII degree (8 degree) area covers an area of 109 square kilometers, mainly involving Caodeng Township, Malkang City, Aba Tibetan and Qiang Autonomous Prefecture, with a total of 1 township.
The VII degree (7 degree) area covers an area of 1,459 square kilometers, mainly involving Caodeng Township, Zuomuzu Township, Longerjia Township, Kangshan Township, Ribu Township, Shaerzong Town, Malkang City, Aba Tibetan and Qiang Autonomous Prefecture, Rong Township, Aba County An Township, Charma Township, Hongyuan County, a total of 8 townships.
The VI degree (6 degree) area covers an area of 4,151 square kilometers, mainly involving Ribu Township, Shaerzong Town, Kangshan Township, Zuomuzu Township, Longerjia Township, Malkang Town, Caodeng Township, Malkang City, Aba Tibetan and Qiang Autonomous Prefecture. Songgang Town, Dazang Township, Baiwan Township, Mulzong Township, Rong'an Township, Kuasha Township, Kehe Township, Anqiang Town, Hezhi Township in Aba County, Charma Township and Jiangrong Township in Hongyuan County, There are a total of 21 townships in Rangtang County, including Shangrangtang Township, Gaduo Township, and Zhongrangtang Town.
In addition, some townships and other parts of Jinchuan County outside the Ⅵ degree (6 degree) area were also affected, and some old houses were damaged and damaged.
This earthquake is a swarm type earthquake. Medium-strong earthquakes of magnitude 5.8, 6.0 and 5.2 occurred successively in a short period of time, and the superposition of earthquake damage is obvious.
Most of the houses in the earthquake area are Tibetan-style stone and wood structures, without fortification measures, and the earthquake resistance is poor. The earthquake caused some houses to collapse and local collapse.
The epicenter of the earthquake is located in the high mountains and valleys. In the region, the mountains are high, the valleys are deep, the slopes are steep, the rock mass is relatively loose, and secondary geological disasters such as landslides, collapses, and rolling stones can be seen everywhere after the earthquake.
After the earthquake, lifeline projects such as roads, electric power, and communications in the epicenter area were severely damaged, and the road from Malkang to Caodeng Township of Provincial Highway 220 was particularly seriously damaged.
In addition, the earthquake also caused a blockage of a river in Hongyuan County.
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