This morning (August 8)
A magnitude 6.4 earthquake occurred in the sea area of Yilan County, Taiwan.
At 10:49 on August 6,
A magnitude 2.7 earthquake occurred in Zengcheng District, Guangzhou.
This made many people start to wonder why
Why are earthquakes frequently occurring recently?
There are also earthquakes in Guangdong?
The answer is: has it!
In fact, earthquakes in Guangdong often occur. Just recently on July 24, a magnitude 2.9 earthquake occurred in Jiangcheng District, Yangjiang City, Guangdong Province. Based on the Guangdong earthquake data from 1970 to 2019 compiled from the Guangdong Earthquake Information Network, we can see where the earthquakes in Guangdong are the most frequent and the trend of the earthquakes in the past 50 years...
01
Four major earthquake gradient areas
Heyuan and Yangjiang The most frequent earthquakes
In the past half century, a total of 58,633 earthquakes occurred in Guangdong (the statistical time was January 1970 to August 2019, the same below), with a total of 225 magnitudes of 4-4.9, accounting for 0.38%; a total of 45 magnitudes of 5-5.9, accounting for 0.77‰. There are 6 magnitudes 6-6.9, and 2 magnitudes 7-7.9. It should be noted that earthquakes above magnitude 6 occur in the Taiwan Strait, South China Sea and Beibu Gulf.
According to the number of earthquakes in Guangdong in the past 50 years, earthquakes in Guangdong can be divided into 4 gradients. Heyuan can be said to be a high-frequency earthquake zone, with a total of 29,899 earthquakes. In other words, more than half of the earthquakes in in the province occurred in Heyuan . The second is Yangjiang, with a total of 11,805 earthquakes, and the first gradient was at the same time.
Q
Why do Heyuan and Yangjiang frequently occur in earthquakes?
A
Related literature shows that Heyuan and Yangjiang are located in the Heyuan-Yangjiang earthquake zone . This zone is mainly composed of the Shaowu-Heyuan fault, the Guangzhou-Conghua fault, and the Enping fault. Most of them are in Guangdong. The largest earthquake was the Yangjiang 6.4 magnitude earthquake in 1969.
Q
So do Guangdong also have earthquake zones?
A
In fact, the Heyuan-Yangjiang earthquake belt is one of the four earthquake belts in the southeast coastal earthquake zone in the South China earthquake zone. In addition, there are coastal earthquake belts (i.e., Quanzhou -Shantou earthquake belts, but the earthquake activity is not in the land of Quanzhou and Shantou, but in its coastal areas), Shantou-Huilai earthquake belts (i.e. between the Pingtan- Nanao fault and Lianhuashan fault), and Wuchuan-Sihui earthquake belts.
range division diagram of the four major seismic zones along the southeast coast.
02
The highest magnitude of each city
The regions vary greatly. The magnitude is 2.8~5.4 magnitude
00~250 earthquakes in Guangdong every year with earthquakes above magnitude 2. There are many major earthquakes in history that cause casualties. For example, in 1918, a magnitude 7.3 earthquake occurred in Nanao, Shantou, a magnitude 6.1 earthquake occurred in Heyuan in 1962, and a magnitude 6.4 earthquake occurred in Yangjiang in 1969. In the past 50 years, the magnitude of earthquakes in various cities in Guangdong has rarely exceeded magnitude 5. Among them, the magnitude 5.4 earthquake that occurred in Yangjiang on January 28, 1986 was the highest level of earthquake in Guangdong in the past 50 years, followed by the magnitude 5.2 earthquake that occurred in the east of Heyuan on February 16, 2012.
03
earthquake magnitude concentration
2~3 magnitude earthquakes most frequently occur
04
Earthquakes occur in recent years, are earthquakes more frequent?
A
Looking at the frequency and trend of earthquakes in Guangdong in the past 50 years, overall, the earthquake in Guangdong this year is at a normal level. However, Guangdong's topography has its own characteristics, with many mountains and rivers, fractures and large terrain height differences, resulting in large differences in the frequency and earthquake intensity of earthquakes in various regions. In addition to Heyuan, located in the northern mountainous areas, and , Shaoguan, , Yangjiang, located in the coastal economic belt, are all earthquake-related areas.
05
Guangdong earthquake warning has a set of
Some areas have achieved 60-second warning
Guangdong Provincial Earthquake Bureau Earthquake Monitoring Center Director Huang Zhidong said that Guangdong has now built a set of " Pearl River Delta Earthquake Warning Network ", and some areas have initially formed earthquake warning capabilities.
"can achieve a 5-60-second warning time for the Pearl River Delta and surrounding areas after a destructive earthquake occurred in the offshore estuary area of the eastern coastal area of ." Huang Zhidong introduced.
Next, 1,172 earthquake stations are planned to be built and renovated, so that most areas in the province have the ability to report intensity quickly and warning.
Small knowledge that must be mastered about earthquakes
Emergency shock absorption Remember this major principle:
Take risks on the spot during earthquakes and quickly evacuate after the earthquake!
Protect important parts
Head and neck: Cut your head and protect your head and neck with your hands. You can use a quilt and pillow to put it on your head
Eyes: Cut your head and close your eyes to prevent foreign objects from harming
Oral and nose: Cover your mouth and nose with a wet towel to prevent dust, poisonous gas, etc.
Sustain yourself and save each other Methods
adopts calls and taps to determine the exact location of the survivor, and can also learn about the situation from the family or neighbors;
is approaching the burial of people, pay attention to distinguishing the support and the burial of people, and do not use sharp tools to dig ;
During the lifting and rescue process, should not forcefully pull ;
should not forcefully pull ;
set signs for injured people who are difficult to rescue for the time being, and wait for rescue.
Source | Southern Daily, Southern+ Reporter Feng Yuyi Intern Ye Shilan
