In recent days, large-scale earthquakes have occurred globally. On April 3, a magnitude 7.3 earthquake struck the eastern sea area of Hualien County, Taiwan, with a depth of 12 km. As of April 5, this earthquake has resulted in 12 deaths, 1123 injuries, and 634 people still trapped. On April 5, on another side of the globe, a magnitude 4.8 earthquake occurred on the east coast approximately 60 km from New York City, with a depth of about 5 km. Although the magnitude of this earthquake was not significant, it was the strongest earthquake in New York in 140 years, a region where large earthquakes rarely occur. In Japan, a magnitude 6.1 earthquake occurred off the east coast of Honshu on April 2; on April 6, another magnitude 5.3 earthquake occurred far offshore of the east coast of Honshu, with a depth of 10 km.
If one looks at the longer time frame and broadens the scope, it can be seen that an increasing trend of large-scale earthquakes occurring globally in the past one or two years. On January 1 this year, a large-scale earthquake occurred on the Noto Peninsula in Japan, with the strongest magnitude reaching 7.6. On January 3, a magnitude 5.5 earthquake occurred in Argentina; and on January 4, a magnitude 5.7 earthquake occurred in the Fiji Islands.
According to data released by the China Earthquake Networks Center (CENC), in 2023, there were a total of 129 earthquakes worldwide with a magnitude of 6 or above, including 19 earthquakes with a magnitude of 7 or above, with the largest being two 7.8 earthquakes in Turkey on February 6. If we look at earthquakes with a magnitude of 7 or above, it is basically consistent with the average annual frequency of 18 times since 1900, significantly higher than the activity level of 7 earthquakes with a magnitude of 7 or above in 2022. The global seismic activity of earthquakes with a magnitude of 7 or above shows a clear trend of transition from weak to strong. According to incomplete statistics, there were at least 12 earthquakes with a magnitude of 6 or above worldwide in December 2023 alone.
Figure: Map of Global Earthquakes with Magnitude 7 or above in 2022 and 2023
Source: Internet.
From the distribution of time and space of earthquakes, the coastal areas of the Pacific Ocean and the Himalayan volcanic earthquake zone are still the high-risk areas for global earthquakes. Currently, more than 90% of earthquakes worldwide still occur in this earthquake zone. According to statistics from the CENC, 95% of global earthquakes with a magnitude of 7 or above occurred in the Eurasian seismic zone and the northeastern boundary of the Australian plate in 2023. Among them, earthquakes with a magnitude of 7 or above occurred 7 times in the Eurasian seismic zone and 11 times in the northeastern boundary of the Australian plate. From January to June 2023, there were 14 earthquakes with a magnitude of 7 or above globally, accounting for 73.7% of the total number of earthquakes for the whole year, showing a relatively concentrated spatial and temporal distribution of earthquake activity.
According to data released by the CENC, in 2023, China experienced a total of 18 earthquakes with a magnitude of 5 or above. Among them, there were 11 earthquakes with a magnitude of 5 or above on the mainland, including 2 earthquakes with a magnitude of 6 or above; there were 4 earthquakes with a magnitude of 5 or above in offshore areas. Taiwan experienced 3 earthquakes with a magnitude of 5 or above, with the largest occurring on October 24 in the offshore area of Hualien County, with a magnitude of 5.9. Some analysts have noted that earthquakes with a magnitude of 5 or above in Taiwan are notably weaker, and seismic activity remains relatively calm for earthquakes with a magnitude of 7. The level of seismic activity in China in 2023 significantly decreased compared to 2022 (26 occurrences), marking the lowest frequency year since 2000. In Taiwan, seismic activity above a magnitude of 7 has remained calm for 17 years since the 7.2 magnitude earthquake in the Hengchun offshore area on December 26, 2006, the longest calm period since 1900. However, the magnitude 7.3 earthquake that occurred in the eastern sea area of Hualien County on April 3 immediately broke the notion of an extended calm period for large earthquakes in Taiwan as previously suggested.
As a geological phenomenon, earthquakes are a type of geological activity that occurs frequently, and it seems difficult to accurately grasp and define the regularity of their occurrence and development. One prominent manifestation is the significant controversy over whether earthquakes can be "predicted". Based on the incomplete understanding of researchers at ANBOUND, the mainstream opinion among seismological community in China is that earthquakes cannot be predicted. Therefore, since the accurate prediction of the Haicheng earthquake in the previous century, it appears that the Chinese seismological community has been hesitant to make earthquake predictions and reluctant to take responsibility for earthquake prediction and related research.
However, the complexity of accurately predicting earthquakes does not mean that humanity is unable to study their patterns, nor does it mean abandoning efforts to predict earthquakes entirely. From the trend of large earthquakes globally intensifying over the past two years, we may need to remain vigilant and attentive to the increasing trend of stronger earthquakes. Some seismic experts believe that based on statistical data, the active period of earthquakes typically lasts around 10 to 20 years. While it may not necessarily mean that now is the period of active earthquake period on a global scale, China's seismic active period has not yet ended. Some experts also point out that since the Wenchuan earthquake in 2008, mainland China has not experienced any earthquakes with a magnitude of 7 or above for nearly 15 years. Through the periodic analysis of earthquakes, China faces a challenging seismic situation, requiring increased attention to the trend of increasing large earthquakes and the strengthening of research efforts.
In the past few decades, globalization has continued to deepen, with the improvement of free trade and supply chains enabling investments in manufacturing and services to be globally distributed. If there is a trend of increasing large earthquakes globally in the future, it will have a certain impact on the industrial investments and layout choices of multinational corporations. For example, future capital-intensive and technology-intensive heavy asset investments may need to consider the impact of earthquakes and other natural disasters. Similar investment layouts may focus more on avoiding areas with high earthquake activity. Although large earthquakes are only a very rare natural disaster phenomenon, for certain key industries with massive investments, they are still a risk in investment layout that needs to be actively avoided as much as possible.
Final analysis conclusion:
From statistical data, it is evident that large earthquakes globally are showing a clear trend of increasing intensity. For the trend of more frequent large earthquakes, relevant countries need to pay attention on this. For certain key industries with massive investments, there needs to be more consideration given to the risk posed by earthquakes.
