The World’s Most Earthquake-Prone Areas and Countries

The world’s seismically most active zones are:

• the Circum-Pacific belt,
• the Alpide belt,
• the mid-Atlantic Ridge.

The Ring of Fire

The Circum-Pacific belt, also known as the “Ring of Fire”, is the world’s greatest volcanic and earthquake belt, where 81 percent of recorded earthquakes occur. It is located along the rim of the Pacific Ocean along boundaries of tectonic plates, where various plates are subducting beneath another plate. Earthquakes are thus caused by slips between plates and within them. The largest instrumentally recorded earthquakes along the Circum-Pacific belt were a magnitude 9.5, Chile 1960 and a magnitude 9.2, Alaska 1962 earthquakes¹.

Picture 1: Ring of fire.

Alpide Belt

Following the Circum-Pacific belt is the so-called Alpide belt. This is a geographic area located in the southern region of Eurasia, where 17 percent of the world’s largest earthquakes occur. It runs from Java to Sumatra all the way through the Himalayas, the Mediterranean, and out into the Atlantic. Some of the most destructive earthquakes in the instrumental era along this belt were the Sumatra, 2004, magnitude 9.1 earthquake, which generated a tsunami that killed over 230.000 people, and the Pakistan, 2005, magnitude 7.6 earthquake, where over 80.000 fatalities were reported¹.

The Mid-Atlantic Ridge

Last but not least, is the mid-Atlantic Ridge, which is an example of a divergent plate boundary – an area where two tectonic plates are spreading apart. The most earthquake-prone area along the mid-Atlantic Ridge is Iceland, which is located directly over it. However, this belt is deep underwater and far from any human infrastructure, so in general, it does not influence much of human lives¹.

Picture 2: Photo of the world's tectonic plates.

Seismically Most Active Countries

No doubt that Japan is one of the most seismically active countries in the world. It is situated on the Pacific “Ring of Fire”, where the Philippine Sea plate subducts the Okinawa plate and the Amurian plate. Due to the many earthquakes that occur there on a daily basis, Japan has developed the densest seismic network in the world, which makes it possible to record many earthquakes. Japan has a system that detects seismic waves via a network of more than 1,000 seismometers around the island. The system in turn pings phones, TVs, and radios across the country, stopping trains and providing people with a few extra seconds to prepare for the earthquake².

Picture 3: Picture of the tectonic plates (Eurasian, North American, Pacific, and Philippine plates).

Does this mean that most of the earthquakes worldwide actually happen in Japan? No. It just means that their seismic network is developed to the point, that it can also recognize weaker earthquakes. It is probably Indonesia that experiences the most earthquakes but does not possess sparse seismic instrumentation, which makes it impossible to record all the weaker earthquakes. Indonesia is located at the center of the complex tectonic zone where the Pacific, Eurasian, and Indo-Australian plates collide. Earthquakes that are recorded or felt occur there more than three times per day³.

The country that experienced the most fatalities due to earthquakes is China. The three most fatal earthquakes were:

• M8.0 Shaanxi earthquake (1556) with total deaths of 830.000;
• M7.5 Tangshan earthquake (1976) with total deaths of 242.769;
• M8.3 Haiyuan earthquake (1920) with total deaths of 200.000.

China is located on the top of the Eurasian plate, part of the Indian plate, and a small part of the Philippine Sea plate. Being located in such an active area, China has experienced many catastrophic earthquakes during its history and accounts for roughly half of all earthquake deaths.

Sources:
1) United States Geological Survey (USGS). Where do earthquakes occur? Accessed on 20-Apr-2022. Available at: https://www.usgs.gov/faqs/where-do-earthquakes-occur
2) Brueck, Hilary and Kotecki, Peter. 2018. New earthquake maps reveal never-before-seen detail about threats to buildings and people — here's who's most at risk around the world. Accessed on 20-Apr-2022. Available at: https://www.businessinsider.com/most-earthquake-prone-countries-in-the-world-2018-12#china-a-seismically-active-country-with-the-worlds-largest-population-accounts-for-roughly-half-of-all-earthquake-deaths-1
3) Nugraha, Zikry Adjie. 2021. EDA and Visualization of Earthquake Occurrence in Indonesia over the last 20 years using R. Accessed on 20-Apr-2022. Available at: https://towardsdatascience.com/eda-and-visualization-of-earthquake-occurrence-in-indonesia-over-the-last-20-years-using-r-4c76e94e94c2?gi=135fa042b63a