Kathmandu, Jan. 7: Over the past 22 days from mid-December, 2024 to first week of January, 2025, a total of 10 earthquakes with magnitudes of 4 or above on the Richter scale have been recorded across Nepal, predominantly in the Western region, with one or two detected in the east.

Seismologists warn that this may be an indication of Western Nepal’s probability to become the epicentre of a major earthquake at any time.

The National Earthquake Monitoring and Research Centre (NEMRC), Lainchaur, Kathmandu, confirms that the first tremor of the ones mentioned above struck Bajhang on December 17, followed by another quake in the same district on December 18. Since then, districts including Manang, Bajura, Darchula, Jajarkot, Baitadi, Mugu and Sindhupalchok have experienced seismic activities.

Data reveals that the strongest earthquake in this duration occurred on December 20 in Bajura, measuring 5.2 on the Richter scale. The second-largest tremor, at 4.8 magnitude, was recorded on January 2, 2025 having its epicentre at Majhitar area in Sindhupalchok district.

Excluding the quake in Sindhupalchok, all other nine tremors were concentrated in Western Nepal. According to experts, the region shows increasing signs of vulnerability, with a likelihood of a 6.0 magnitude or higher earthquake occurring at any time.

The recent frequency of seismic activity in Western Nepal has raised concerns among researchers and the general public alike, emphasising urgent need for preparedness in the event of a major quake, suggest seismologists.

According to Dr. Lok Bijaya Adhikari, Senior Divisional Seismologist at the Research Centre, these earthquakes measuring 4.8 to 5.0 are not of a magnitude that could cause significant damage. As a result, the tremors were only felt in areas close to the epicentre.

Dr. Adhikari said that, on average, Nepal experiences up to 10 recordable earthquakes daily.

“Considering the number of earthquakes in Nepal over the year, the available technology here records an average of 10 earthquakes per day,” he explained. “Our technology can only record earthquakes with a magnitude of 2 or higher, but there are many smaller quakes below this threshold that go unrecorded.”

While the Centre records earthquakes of 2 magnitude and above, they only publicly disclose those with a magnitude of 4 or higher, according to Dr. Adhikari.

“In simple terms, frequent earthquakes in Nepal indicate the presence of seismic activity in the Western region,” he stated. “Smaller earthquakes release less energy, whereas larger earthquakes release much more energy.”

According to seismologists, there are seven major tectonic plates on earth, all of which are in constant motion. When these plates collide, earthquakes occur. The location where two plates meet experiences the most intense seismic activity.

Dr. Adhikari stated that the recent earthquake has not significantly dissipated the vast energy accumulated beneath Western Nepal. He explained, “This earthquake is only of moderate intensity and has not released the stored subterranean energy.” Dr. Adhikari further clarified that this earthquake is not an aftershock of the 2015 Gorkha earthquake.

Seismologists classify earthquakes below magnitude 6 as minor, those between magnitude 6 and 7 as moderate, and those between magnitude 7 and 8 as powerful.

Earthquakes exceeding magnitude 8 are categorised as mega quakes. According to Dr. Adhikari, energy capable of triggering a mega-quake remains stored beneath Western Nepal, and the recent tremor has played a negligible role in releasing it. Therefore, the risk of a mega-quake in western Nepal remains highly likely at any time.

Western Nepal has not experienced a major earthquake for over 500 years. The last recorded mega-quake in the region occurred in 1505 AD. Although no detailed records exist of its impact, the ongoing collision between the Indian and Eurasian tectonic plates suggests the potential for an earthquake exceeding magnitude 8 in Western Nepal.

Dr. Adhikari noted that the continuous northward movement of the Indian subcontinent’s crustal layer is pressing the Eurasian plate which places the entire Himalayan region at high seismic risk.

The larger the earthquake, the more significant the release of accumulated subterranean energy. Dr. Adhikari emphasised, “The energy released by the 6.4 Richter scale earthquake in Ramidanda of Jajarkot on November 3, 2023, was minuscule compared to the massive energy stored beneath Western Nepal.” Ramidanda epicentre quake had taken lives of 153 people with 364 injuries.

Bharat Prasad Koirala, another senior seismologist, said that the seismic risk is not confined to Western Nepal; the Kathmandu Valley and surrounding areas also remain vulnerable to powerful earthquakes. The 2015 Gorkha earthquake, with a magnitude of 7.8, released energy stored beneath a 150-kilometre stretch extending from Gorkha to Dolakha and Ramechhap. However, according to seismologists, the energy stored beneath the southern region of Kathmandu remains unreleased.

Koirala explained that significant energy remains trapped beneath the region south of Kathmandu, though it should ideally have been discharged along the Chure range. This persistence of accumulated energy continues to pose a seismic threat to Kathmandu and its surroundings.