Every day, we keep hearing about earthquake tremors being felt in different regions. The Indian subcontinent is a high-risk area for earthquakes, hurricanes, floods, tsunamis, and landslides. According to seismic zoning mapping, India is divided into 4 zones. These zones are divided on the basis of the estimation of the intensity of the earthquake. India is divided into Zone 2, Zone 3, Zone 4, and Zone 5. While Zone 2 is the least dangerous, Zone 5 is the most dangerous.
Earthquakes always bring with them destruction. The occurrence of an earthquake is a natural process, beyond human power. Hence, prevention is the only way. Further, the most important aspect is to be able to accurately predict the time of the earthquake. This work is done by seismic observatories.
35 upcoming Seismic Observatories in India
The Government of India has decided to increase the number of seismic observatories to create a dense network of observatories across the country. This would enable every region to prepare for an earthquake in advance.
Union Minister, Dr. Jitendra Singh, Department of Science and Technology, said that 35 seismic observatories will be set up in India by the end of this year. He further said that in the next five years, 100 more such observatories would be built in the country by the Central Government.
Only 115 observatories at present
At present, there are only 115 observatories in the country. Addressing the inaugural function of the Joint Scientific Assembly of the International Association of Geomagnetism and Aeronomy (IAGA) – International Association of Seismology and Physics of the Earth Interior (IASPEI), Union Minister Jitendra Singh said that in the last six and a half decades since independence i.e. in the history of 65 years, there were only 115 seismic observatories in the country, but under the leadership of Prime Minister Narendra Modi, there is now going to be a huge increase in the number of seismic observatories in the country.
How does an earthquake occur?
The earthquake is characterized by severe shaking of the ground and severe shaking of structures above the ground. According to the National Disaster Management Authority, this happens due to the release of the transmitted pressure of moving lithospheric or crustal plates.
The Earth’s crust is divided into 7 large plates, which are 50 miles thick. It moves slowly and steadily over the Earth’s interior and many smaller plates. Earthquakes are basically tectonic, that is, moving plates are mainly responsible for the shaking in the ground.
Earthquakes in India
Major earthquakes occur around the Himalayas. Urbanization, widespread unscientific construction, and exploitation of natural resources have led to an increase in the number of earthquakes in the Indian subcontinent.
During the last 15 years, the country has suffered 10 major earthquakes, which have claimed more than 20,000 lives along with the country’s wealth. According to the country’s current seismic zone map, 59% of India’s land area is under a moderate to severe seismic hazard warning, which means that India is prone to earthquakes of magnitude 7 and above.
In fact, the entire Himalayan region is considered favorable for large earthquakes of magnitude 8.0. There have been 4 such major earthquakes in a relatively short period of 50 years, which have proved this point. An earthquake of magnitude 8.7 struck Shillong in 1897, Kangra of magnitude 8.0 in 1905, of magnitude 8.3 along the Bihar-Nepal border in 1934, and of magnitude 8.6 in the Assam-Tibet border in 1950.
According to the National Disaster Management Authority, scientific publications have warned about the possibility of a powerful earthquake in the Himalayan region, which could adversely affect the lives of millions of people in India.
Northeast region is more vulnerable
The northeastern region of the country continues to receive moderate to large earthquakes at frequent intervals. There have been several mild earthquakes in the region since 1950. On average, the region has been hit by one earthquake with a strength of more than 6.0 per year.
The Andaman and Nicobar Islands are also located on the inter-plate boundary and are prone to frequent destructive earthquakes.
Role of IAGA
Speaking at the event, Union Minister Dr. Singh said that as a recognized science of the composition, structure, and processes, which govern our planet, has probably reached its zenith today as human society grapples with challenges at multiple levels of interactions with Mother Earth. IAGA and IASPEI will take the country forward.
The Minister expressed the hope that the International Association of Geomagnetism and Aeronomy (IAGA) – the joint scientific assembly of the International Association of Seismology and Physics of the Earth Interior (IASPEI) will act as a catalyst in bringing on board a greater number of researchers and practitioners from the global community to work on issues related to rendering science to society.
He said that it is a fitting environment for the two scientific communities to come together to forward research in their niche as well as pursue new avenues of cross disciplinary investigations. The Minister added that the linkage between the deep earth structure and geomagnetism, and the role of fluids in earthquake nucleation are a few examples to emphasize the significance of the Joint Scientific Assembly of these two Associations to promote cross-disciplinary research.
IAGA and IASPEI will together organize a joint meeting in 2021, which will be hosted by CSIR-NGRI in collaboration with the Ministry of Earth Sciences, Government of India. It is expected that both institutions will take the country to greater heights in this field.