Photo : TDM
Bangladesh is one of the most natural disaster-prone countries in the world, with natural calamities such as cyclones, floods, droughts, and others causing significant damage to lives, resources, and the environment every year, primarily due to its adverse geographical location.
Earthquakes, considered one of the most concerning disasters, can occur anytime and anywhere without prior prediction, leading to potential widespread destruction. While mild and moderate earthquakes have been recently experienced in the country, severe earthquakes have occurred in this region in the past. Scientists expressed concerns that an earthquake with a magnitude of 7 to 8 may strike Bangladesh in the near future, emphasising the need for preparedness.
According to experts, there is a possibility of strong earthquakes in the hilly areas extending from Sylhet to Chattogram in the country. Along with Bangladesh, India's Manipur, Mizoram, and Myanmar's mountainous regions are also at risk. Furthermore, the haor of Kishoreganj through the Meghna River, along the Bay of Bengal and the Andamans, is located at the junction of two tectonic plates—the Burma plate in the east and the Indian plate in the west. The upper part of their convergence, from Sunamganj east to Manipur and Mizoram, is 'locked,' meaning that energy is accumulating here.
Experts warn that there is enough stored energy to trigger an earthquake with a magnitude of 8.2 to 9, which could occur at any time. It's only a matter of time.
Mild and moderate earthquakes this year:
So far this year, there have been 10 mild and moderate earthquakes in the country. Although they have not resulted in significant loss of life or property, experts consider them a precursor to a major earthquake.
The first earthquake to hit Bangladesh this year occurred on February 16. It also affected India's northeastern state of Meghalaya and Bangladesh's northeastern Sylhet district. Fortunately, there was no damage to property in this 3.9 magnitude earthquake.
On February 25, a pair of moderate earthquakes struck Myanmar, felt in Ayawati and Rakhine states of the country as well as Cox's Bazar in Bangladesh. Meteorologist Abul Kalam Mallik of the Bangladesh Meteorological Department informed that the epicentre of the earthquake in Rakhine state was 378 km southwest of Agargaon in Dhaka, with a magnitude of 4.1 on the Richter scale.
An earthquake with a magnitude of 4.6 was felt in Chattogram on April 30. Meghnath Tanchangya, assistant meteorologist at the Chattogram Meteorological Office, said that the earthquake originated at Latitude 22.93 degrees north, Longitude 94.19 degrees east in Maulaik, Myanmar. It was located 400 km southeast from the earthquake monitoring and research centre in the capital.
An earthquake was felt in the capital on May 5. Farzana Sultana, assistant meteorologist at the Bangladesh Meteorological Department, said that a 4.3 magnitude earthquake occurred in the capital on Friday morning. Its epicentre was in Dohar, located 30 kilometres southeast of the capital Dhaka. Fortunately, there was no property damage resulting from this incident.
On June 16, an earthquake was felt in various parts of the country, including the capital Dhaka. Reports of earthquake activity came from Sylhet, Moulvibazar, and Sunamganj. According to the website of the Meteorological Department, the epicentre of the earthquake was Golapganj in Sylhet. However, immediately after the earthquake, various media sources reported that the epicentre was in Shillong, India.
On August 14, a 5.5-magnitude earthquake was again felt in Sylhet. It was also felt in some districts of the country, including Dhaka. According to information from the Earthquake Observatory and Sylhet Meteorological Office, its epicentre was in Meghalaya, Assam. It originated at a depth of 35 km. The distance from Dhaka to the epicentre is 228 km northeast.
Exactly 16 days later, on August 29, a mild earthquake was felt again around the city of Sylhet. Initially, it was reported to have a magnitude of 3.5. The epicentre of the earthquake was Jaintapur in the Meghalaya state of India.
On September 9, a mild earthquake measuring 4.4 on the Richter scale struck the northeastern state of Assam in India. The Sylhet district of Bangladesh was also shaken by the earthquake. According to preliminary information, the epicentre of this earthquake is about 43 km below the surface. According to the Earthquake Monitoring Center of Bangladesh, an earthquake with a magnitude of 4.4 was felt in Sylhet. The distance from Dhaka to the epicentre is 263 km northeast in Kachhar, Assam, India.
A 4.2-magnitude earthquake was last felt in Tangail on September 17. Its epicentre was at Tangail Sadar, 59 km from Dhaka. The earthquake occurred at a depth of 5 km below the surface.
It is true that the country is at risk of earthquakes due to its geographical location. There are differences of opinion regarding the magnitude of earthquakes among geologists and earthquake experts.
The country is prone to major earthquakes, with three active tectonic plates:
Meteorologist and earthquake expert at the Bangladesh Meteorological Department, Mominul Islam, said, “Bangladesh is at risk of earthquakes due to its geographical location because three tectonic plates surround Bangladesh. Their intersection occurs around our borders. For example, the Himalayas to our north lie on the Eurasian Plate.”
“Our location is on the Indo-Australian plate, and before us is the Burma Micro Plate. All three of these plates are connected and active. These plates are in constant motion, moving about five centimetres or 50 millimetres per year. This means that every year, we are moving northeast by five centimetres, just as the entire world is also in motion.”
The location of the plate boundary is within 120 km of the border:
In response to the question of whether Bangladesh is at risk of earthquakes or not, Mominul said, "Based on past events, it can be said that wherever there is a plate boundary line, i.e., where there is a junction of two plates, there is a high probability of a significant earthquake."
He also said, "Since Bangladesh is located very close to the plate boundary (the plate boundary is within 100 or 120 km from the border of Bangladesh), we are definitely at risk. There have been major earthquakes in the region in the past. Since the Earth accumulates energy as it moves and releases energy through plate boundaries, it can be said that there is a possibility of large earthquakes in Bangladesh."
Renowned geologist Professor Dr. Syed Humayun Akhtar said that 800 to 1,000 years ago in Mainamati, Cumilla, the plates released their stored energy. After that, they have been accumulating new energy over the past 1,000 years. This means that enough energy has been stored to trigger an earthquake with a magnitude of 8.2 to 9 at any time.
He emphasized that earthquakes have occurred in several places in the country, including Sylhet and Rupganj in Narayanganj, and these are signs of a major earthquake. A significant earthquake could occur today, tomorrow, or even 50 years from now.
Mehedi Ahmed Ansary, a professor in the civil engineering department at Bangladesh University of Engineering and Technology (BUET), holds a different opinion regarding the magnitude of earthquakes in Bangladesh.
“No earthquake of magnitude 9 has occurred in this region in the past. Here, an earthquake with a magnitude of 7 to 8 can take place,” he told The Daily Messenger.
Referring to past events, he noted that between 1762 and 1930, there were seven major earthquakes, none of which exceeded a magnitude of 8. In 1869, there was an earthquake with a magnitude of 7.5, while in 1885, it was a magnitude 7 earthquake. In 1897, another earthquake had a magnitude of 8.1, in 1918, it was 7.6, and in 1930, it was 7.1.
“An earthquake with a magnitude of 7 to 8 could occur in Bangladesh at any time, as this type of earthquake occurs approximately every 150 years. The epicentre could be within 100 kilometres of Dhaka,” he told The Daily Messenger, emphasising the need for Bangladesh to prepare for earthquake events, identify risky buildings, and retrofit weak structures.
TDM/SD
