Great Nicobar Infrastructure Project Earthquake Risks

The Great Nicobar Infrastructure Project (GNIP), valued at ₹72,000 crore, plans major development on Great Nicobar Island. These include a trans-shipment port, international airport, township, and power plant. The project faces scrutiny due to seismic risks in this highly active zone. The region is prone to earthquakes and tsunamis, a fact brought into light by the devastating 2004 Indian Ocean tsunami. Recent Environment Impact Assessment (EIA) reports have downplayed the chances of a mega earthquake, but scientific experts urge caution.
Seismic Risk Assessment in GNIP
The EIA report, nearly 900 pages long, was prepared by Vimta Labs for the Andaman and Nicobar Islands Integrated Development Corporation. It states the probability of a mega earthquake similar to the 2004 event is low. This conclusion relies heavily on a 2019 Indian Institute of Technology-Kanpur (IIT-Kanpur) study. The study estimates a return period of 420–750 years for magnitude 9 or above earthquakes and 80–120 years for earthquakes above 7.5 magnitude in the region.
Scientific Evidence and Gaps
The IIT-Kanpur study examined sediments from South Andaman and found evidence of seven large tsunami events in 8,000 years. It also noted a 2,000-year gap in sediment data, which adds uncertainty to predictions. However, this important detail is missing from the GNIP EIA report. Experts show the need for site-specific studies in Nicobar, as earthquake origins and impacts may differ from those in Andaman or Indonesia.
Fault Lines and Earthquake Dynamics
The Andaman-Sumatra fault line is highly vulnerable to large earthquakes. Scientists warn of unknown rupture zones south of Andamans towards Nicobar. The process of earthquake recurrence is non-linear, meaning long quiet periods can be followed by sudden massive quakes. Local fault lines and land-level changes on Great Nicobar Island increase vulnerability. This makes infrastructure projects in the area particularly risky.
Government and Expert Perspectives
A senior Ministry of Earth Sciences scientist admitted no specific seismic studies were done for the GNIP sites. They emphasised the impossibility of predicting exact earthquake timing. Instead, calculated risks must be accepted, and structures designed to seismic codes. Meanwhile, the National Green Tribunal has ordered a review of environmental concerns including biodiversity loss and tribal impacts.
Historical Context and Project Concerns
The Nicobar Islands suffered greatly in the 2004 tsunami caused by a 9.2 magnitude earthquake off Indonesia’s coast. Over 1,500 lives were lost in the islands, and around 10,000 Indians died overall. The region is classified under the highest seismic risk category due to the Indian plate subducting beneath the Burmese Microplate along the Andaman Trench. This tectonic setting makes the area prone to sudden and severe seismic events.