In 2023, India experienced a significant surge in seismic activity, largely attributed to the active Almora Fault in western Nepal. Three major earthquakes rattled the region, with magnitudes of 5.8 on January 24, 6.2 on October 3, and 6.4 on November 3. The aftermath of these quakes resulted in continuous tremors throughout the year, affecting neighboring countries, including India, Afghanistan, Pakistan, and Nepal.
The seismic activity in the region is not unexpected, given its proximity to the Himalayas, an area prone to earthquakes due to the collision of tectonic plates. The collision of the Indian Tectonic Plate with the Eurasian Plate generates ongoing seismic events in the region.
The statistics for earthquake occurrences in recent years highlight the intensified seismic activity
•Year 2023: 124 earthquakes recorded.
•Year 2022: 65 earthquakes recorded.
•Year 2021: 60 earthquakes recorded.
•Year 2020: 61 earthquakes recorded.
The magnitudes of the earthquakes in 2023 were distributed as follows:
•97 earthquakes with magnitudes ranging from 3.0 to 3.9.
•4 earthquakes with magnitudes from 4.0 to 4.9.
•4 earthquakes with magnitudes from 5.0 to 5.9.
•2 earthquakes with magnitudes from 6.0 to 6.9.
The epicenter of these seismic events lies within a 2500 km stretch from Kashmir to Arunachal Pradesh, covering the Himalayan region. The Himalayas, formed by the collision of tectonic plates, act as a storehouse of energy. The ongoing convergence of the Indian Plate and the Eurasian Plate results in the accumulation of energy, which is periodically released as earthquakes.
The thickness of the Earth’s crust varies across the Himalayas, with a bowl-like formation extending from Nanga Parbat in the Indus Valley to Namcha Barwa in the North-East. The bowl-shaped structure represents the region where energy is stored, leading to seismic activity.
The seismic risk zones in India are categorized into five zones, with the fifth zone being the most susceptible to earthquakes. The fifth zone includes parts of Jammu and Kashmir, Himachal Pradesh, Uttarakhand, Gujarat (Rann of Kutch), northern Bihar, northeastern states, and the Andaman and Nicobar Islands.
The fourth zone encompasses the remaining parts of Jammu and Kashmir, Ladakh, Himachal Pradesh, Uttarakhand, Haryana, Punjab, Delhi, Sikkim, northern Uttar Pradesh, Bihar, West Bengal, Gujarat, Maharashtra (near the west coast), and western Rajasthan.
The third zone includes Kerala, Goa, Lakshadweep, parts of Uttar Pradesh, Haryana, Gujarat, Punjab, West Bengal, Rajasthan, Madhya Pradesh, Bihar, Jharkhand, Chhattisgarh, Maharashtra, Odisha, Andhra Pradesh, Telangana, Tamil Nadu, and Karnataka.
The intensified seismic activity in 2023 serves as a reminder of the seismic vulnerabilities in the region. As India grapples with the increased frequency of earthquakes, monitoring and preparedness become crucial to mitigate the impact of future seismic events. Public awareness and infrastructure resilience play pivotal roles in minimizing the risks associated with seismic activity in earthquake-prone regions.