China's ** Taiwan Network officially determined: at 23:59 on December 18, it was in Jishishan County, Linxia Prefecture, Gansu Province (35 north latitude).70 degrees, 102 east longitude79 degrees) occurs 6Category 2**, with an epicenter depth of 10 km. Why is it so harmful this time?The Taiwan Network Center of China organized experts to study and analyze the activities near Jishi Mountain in Gansu Province and believed that this time it is located in the southeast of Gansu, about 3 kilometers away from the fault on the northern margin of the nearest fault, Laji Mountain. The results of the preliminary source mechanism solution show that the ** is a thrust rupture.
So what is thrust type rupture?There may be squeezing or separation between the different tectonic plates of the Earth, resulting in relative motion, which is what happens. According to the reason for its formation, it can be divided into tectonics, volcanoes, and collapses. Thrust type is a type of tectonics, which refers to the formation of plates that are squeezed against each other, divided into upper and lower plates at the place where the fracture occurs, and the upper plate moves upward relative to the lower plate, and one plate thrusts into the other.
Yang Yun, a senior engineer of the Jiangsu Provincial Bureau, told the Yangtze Evening News Purple Cow News reporter: "Generally speaking, a fault can be understood as a crack or crack between the rocks on both sides. Because the fracture surface is not vertical, the two sides of the fracture surface are divided into upper and lower walls. When the fault is squeezed twice, the upper wall of the fault moves upward, and the thrust type occurs.
What are the characteristics of this type of **?According to reports, the thrust type ** vibration amplitude is large, the damage energy is large, usually causing surface fractures and terrain changes, which can lead to serious geological disasters such as landslides, debris flows, etc. Moreover, the process of energy release of the thrust type is relatively slow, which will lead to a longer duration and more aftershocks. It usually occurs in the plate convergence boundary zone, and in Chinese mainland, the thrust type ** is mainly distributed along the northeastern and eastern margins of the Qinghai-Tibet Plateau.
According to reports, in 2008 Wenchuan 8Level 0** and Lushan 7 in 2013Grade 0** is also thrust type**, both of which are located in the Longmenshan fault zone in Sichuan, China, which belongs to the Himalaya-Mediterranean** belt, and is affected by the collision between the Indian Ocean plate and the Eurasian plate. Wenchuan** is one of the largest intra-plate thrust types in the world that has occurred since instrumentation ever recorded. Thrust type ** can also cause tsunamis that caused a tsunami that killed at least 230,000 people in Sumatra in 2004 9Category 1** and Japan's 2011 Category 9**, which led to the reactor meltdown and tsunami at the Fukushima nuclear power plant, are all in the thrust type**.
Yangtze Evening News Purple Cow News reporter Xu Yuanyuan Yang Zimeng.
Proofreading by Sheng Yuanyuan.