On January 7, the 2020 National Conference of Earthquake Directors was held in Beijing, and the China Earthquake Administration announced the 2019 Earthquake Annual Report. In 2019, there were 30 earthquakes of magnitude 5 or higher in my country. Among them, there were 20 in the mainland, the largest being the magnitude 6.3 earthquake in Motuo, Tibet on April 24. There were 10 occurrences in Taiwan and offshore, the largest being the 6.7 magnitude earthquake in the waters of Hualien County, Taiwan on April 18.
From the perspective of provinces, there were 10 earthquakes of magnitude 5 or higher in Taiwan and its coastal waters, including 2 earthquakes of magnitude 6 or higher, with a maximum intensity of 6.7. The number and intensity ranked first among all provinces in the country. In the mainland, Tibet had two magnitude 5 and one magnitude 6 earthquakes, with the highest earthquake intensity; Sichuan had 7 magnitude 5 and 1 magnitude 6 earthquakes, with the highest frequency and second intensity; Xinjiang had three magnitude 5 earthquakes, The largest was the magnitude 5.2 earthquake in Tacheng, Xinjiang, on February 2, and the frequency of earthquakes was equivalent to that of Tibet; Gansu had two magnitude 5 earthquakes, the largest being the Xiahe magnitude 5.7 earthquake in Gansu on October 28; and Guangxi had two magnitude 5.2 earthquakes.
Distribution map of my country's earthquakes of magnitude 5 and above in 2018 and 2019. Picture from China Earthquake Administration's 2019 Earthquake Annual Report
There are obvious differences in seismic activity in China's multi-seismic regions
A total of 20 earthquakes with a magnitude of 5 or above occurred on the Chinese mainland in 2019, lower than the average annual average of 24 but higher than the average for 2017-2018, the report said. A 6.3-magnitude earthquake struck Motuo, Xizang province on April 24, 2019, breaking the calm of an earthquake with a magnitude of more than 6 that had lasted 522 days in mainland China.
Meanwhile, the levels of seismic activity in several earthquake-prone regions on the Chinese mainland in 2019 are significantly different. Among them, three earthquakes of magnitude 5 or above occurred in Tibet, the number of which was similar to that in 2018, and the intensity of the earthquakes increased somewhat. Eight earthquakes of magnitude 5 or above occurred in Sichuan province in 2019, including one of magnitude 6, which was the Changning earthquake of Magnitude 6.0 on June 17. Compared with 2018, the number of earthquakes increased significantly and the intensity of earthquakes increased to some extent.
The reporter learned that since the Xingwen earthquake of magnitude 5.7 on December 16, 2018, earthquakes of magnitude 5 or above in the southeastern basin of Sichuan have been continuously active. Eight earthquakes of magnitude 5 or above occurred in Sichuan in 2019, all of which were located in the southeastern region of Sichuan. Among them, the 6.0-magnitude earthquake in Changning from June to July in 2019 included five earthquakes with a magnitude of over 5, and two earthquakes with a magnitude of over 5 occurred in Weiyuan and Zizhong in the north, namely the 5.4-magnitude earthquake in Weiyuan on September 8 and the 5.2-magnitude earthquake in
In addition, there were no earthquakes of magnitude 5 or higher in Yunnan province in 2019, and there have been no earthquakes of magnitude 6 or higher for five consecutive years since 2014. The magnitude 7 earthquakes have been quiet for nearly 24 years, all exceeding the average earthquake interval since 1900. The level of seismic activity in Xinjiang continues to be low. There were 4 earthquakes of magnitude 5 in 2018, the largest being the Jiashi magnitude 5.5 earthquake on September 4, 2018, and there were only 3 earthquakes of magnitude 5 or higher in 2019.
"Record breaking" earthquakes occurred in weak earthquake areas such as Guangxi
In 2019," record-breaking "earthquakes occurred in some areas with weak seismic activity in mainland China, such as the 4.2 magnitude earthquake in Sanya, Hainan province on August 20, and the 4.9 magnitude earthquake along the river in Guizhou province on October 2. The magnitude 5 earthquakes in Guangxi area are active, and two earthquakes above magnitude 5 occur, which are the magnitude 5.2 earthquake in the north current on October 12 and the magnitude 5.2 earthquake in Jingxi on November 25, respectively. The number of earthquakes is obviously higher than the average annual activity level of 0.1.
Earthquakes of magnitude 7 or higher continued to be quiet in Taiwan and offshore areas in 2019, 10 earthquakes of magnitude 5 or above occurred in Taiwan, the largest of which was a magnitude 6.7 earthquake off Hualien Coast on April 18. The maximum earthquake intensity was roughly the same as that of 2018, but the number of earthquakes of magnitude 5 or above decreased. After the 7.2-magnitude earthquake occurred off the coast of Hengchun in Taiwan on December 26, 2006, the earthquake with a magnitude of more than 7 lasted for nearly 13 years, which was the longest period of calm since 1900.
Earthquakes have killed 19 people in China throughout the year
From the perspective of earthquake disasters, there were no major earthquake disasters in China's mainland in 2019. The degree of earthquake disasters was significantly lower than the average level of the past ten years, but higher than 2018.
It is understood that the 2019 earthquake disaster caused 19 deaths and 427 injuries in China. Among them ,13 earthquake disasters occurred in mainland China, resulting in 17 deaths and 411 injuries, and direct economic losses of about 5.9 billion yuan. The most serious earthquake was the 6.0 magnitude earthquake in Changning, Sichuan Province, which caused 13 deaths and 299 injuries, and direct economic losses of about 5.3 billion yuan. The largest earthquake of magnitude was the 6.3-magnitude earthquake in Tibet, causing no casualties or economic losses. Taiwan's 2019 earthquake killed two people and injured 16.