According to the official microblog of China’s National Earthquake Network , it was determined that a 4.8-magnitude earthquake occurred at 22: 46 on February 28 in Luding County, Ganzi Prefecture, Sichuan (29.63 degrees north latitude, 102.01 degrees east longitude), with a focal depth of 8 kilometers.
A magnitude 3.3 earthquake occurred at 00: 49 on March 1 in Luding County, Ganzi Prefecture, Sichuan (29.62 degrees north latitude, 102.00 degrees east longitude), with a focal depth of 8 km.
People in Sichuan Chengdu, Meishan, Ya’an, Mianyang and many other places said they felt the earthquake.
A 3.7 magnitude earthquake occurred 01:58 on March 1 in Gengma County, Lincang City, Yunnan Province (23.86 degrees north latitude and 99.58 degrees east longitude) with a focal depth of 10 kilometers.
Recently, earthquake seems to have become a high-frequency word in the news, has the world entered a period of seismic activity? How to mitigate earthquake disasters? In this regard, experts said that there are many small and medium-sized earthquakes every year, and there have been many strong earthquakes in the history of the world.
Experts have warned that building seismic fortification is one of the most effective ways to mitigate earthquake disasters.
More than 100 earthquakes of magnitude 3 or above have occurred in China this year
In February, news about earthquakes repeatedly showed up on Weibo hot search list. According to the latest earthquake situation report released by the China Earthquake Networks, 11 earthquakes with a magnitude of 3 or above occurred in China between February 20 and February 26. Among them, there were 9 earthquakes with magnitude of 3.0 to 3.9, 2 with magnitude of 4.0 to 4.9, and 0 with magnitude of 5.0 or higher. The largest earthquake was a 4.6 earthquake in Baicheng County, Aksu Prefecture, Xinjiang on February 22.
In addition, since 2023 (as of February 26), 111 earthquakes of magnitude 3 or above have occurred in China. Among them, there were 90 earthquakes with a magnitude of 3.0 to 3.9, 19 with a magnitude of 4.0 to 4.9, one with a magnitude of 5.0 to 5.9, one with a magnitude of 6.0 to 6.9, and none with a magnitude of 7.0 or higher. The largest earthquake was a 6.1 earthquake that occurred in Shaya County, Aksu Prefecture, Xinjiang on January 30.
Globally, there have been several earthquakes this year. On February 6, two major earthquakes measuring 7.8 in magnitude struck Turkey, causing huge disasters. Shortly after, on February 23, another 7.2 magnitude earthquake occurred in Tajikistan, close to the border of China’s Xinjiang region, and there were no reports of personnel.
According to information released by the China Earthquake Networks , since 2023 (as of February 26), a total of 23 earthquakes of magnitude 6 or above have occurred worldwide, including 17 earthquakes of magnitude 6.0 to 6.9 and 6 earthquakes of magnitude 7.0 to 7.9.
The number of earthquakes of magnitude 6 and above in the world in the past ten weeks Source: China Earthquake Networks WeChat Official Account message template
Has the world entered a seismically active period?
“In fact, there are a lot of small and medium-sized earthquakes every year, because during the earthquake disaster in Turkey, people became relatively sensitive to small and medium-sized earthquake activity, so they feel it more.” Xu Xiwei, the first dean of the National Academy of Natural Disaster Prevention and Control and a professor at the China University of Geosciences (Beijing) School of Geography, told chinanews.com.
First of all, the strong earthquake in Tajikistan and Turkey are not directly related. Xu Xiwei explained that the earthquake belt in Turkey occurred north of the Eurasian plate, south of the African plate and the Arabian plate; The earthquake in Tajikistan occurred in the Pamir plateau and is closely related to the northward push of the Indian plate. The occurrence of strong earthquakes in the two places reflects the strengthening of the interaction between the plates in the Himalaya-Mediterranean seismic belt. However, the two regions are relatively independent crustal deformation units and have no direct correlation.
In addition, for the argument that the epicenter moved eastward, Xu Xiwei introduced that from the perspective of plate tectonic boundaries, the Turkish earthquake was in the west, and the Tajikistan earthquake was relatively in the east. Spatially, it was indeed moving from west to east. But in terms of dynamics, the two earthquakes are not directly related. Therefore, it cannot be said that the “epicenter moved eastward.”
Prior to this, Xu Qiang, vice president of Chengdu University of Technology and deputy director of the National weight Laboratory for Natural disasters, also mentioned in an interview that there have been a lot of strong earthquakes all over the world in history, and that it is not the only time today that there have been so many strong earthquakes.
Xu Qiang said that it is not yet possible to judge whether the earthquake in Türkey will lead to an increase in the number of earthquakes worldwide. However, it can be determined that after this earthquake, earthquakes on the East Anatolian fault zone where the Turkish earthquake is located will enter an active period, because the stress on the fault zone will gradually adjust and the adjustment range will gradually expand.
Anti-seismic fortification of buildings is one of the most effective ways to reduce earthquake disaster
China is one of the countries with the most frequent earthquakes and the most serious earthquake disasters in the world, said Han Yan Yan Fawen, a senior engineer at the prediction department of the China Earthquake Networks Center on February 16. It is pointed out that one of the most effective ways to reduce earthquake disaster is to do well the seismic fortification of all kinds of buildings.
In 2022, the National Commission for Disaster Reduction issued the “14th Five-Year National Comprehensive Plan for Disaster Prevention and Reduction.” Zhou Weixin, deputy director of the Planning and Finance Department of the China Seismological Administration, said in introducing the work of protecting against and mitigating earthquake disasters during the 14th Five-Year Plan period that the capacity building for preventing and controlling earthquake disasters will be strengthened. We will accelerate the development of seismic exploration and zoning assessment, complete the investigation of key hidden dangers of earthquake disasters in earthquake-prone areas across the country, and compile the sixth-generation seismic zoning map. We will accelerate the strengthening and renovation of buildings in earthquake-prone areas and improve their seismic fortification capacity.
It is understood that since the founding of the People’s Republic of China, China has completed the preparation of five generations of national seismic zoning maps, which were promulgated in 1957, 1977, 1990, 2001 and 2015.
The China Earthquake Administration formulated the national compulsory standard of the fifth generation “Seismic Parameter Zoning Map of China” (GB1830-2015), which gives the technical elements of the seismic parameter zoning map in China. The basic provisions and methods for determining ground motion parameters are applicable to the seismic fortification of general construction projects, and the compilation of relevant plans such as social and economic development plans, land use plans, disaster prevention and mitigation plans, and environmental protection plans.
Xu Xiwei said in an interview that in addition to the construction of houses across the fault, in the future, if there is a strong earthquake of about 6.5 magnitude, the construction of houses in accordance with the ground motion parameters of the zoning map across the country will be able to crack without falling down as long as there is no cutting corners. Gao Mengtan, a distinguished expert at the Institute of Geophysics of the China Earthquake Administration, also said in an interview that in fact, the collapse resistance of housing buildings designed and constructed in strict accordance with the new seismic standards has been greatly improved.