Seismicity of Rajasthan :

Though the state of Rajasthan has not had a major earthquake in recent years, small to moderate earthquake have been felt in the state. Several faults have been identified in this region out of which many show evidence of movement during the Holocene epoch.

• The Cambay Graben terminates in the south-western part of the state.
• The Konoi Fault  near Jaiselmer trends in a north-south direction and was associated with the 1991 Jaiselmer earthquake.
• Several active faults criss-cross the Aravalli range and lie parallel to each other.
• The most prominent of them is the north-south trending Sardar Shahr Fault and the Great Boundary Fault which runs along the Chambal River and then continues in the same direction into Uttar Pradesh.

However, it must be stated that proximity to faults does not necessarily translate into a higher hazard as compared to areas located further away, as damage from earthquakes depends on numerous factors such as subsurface geology as well as adherence to the building codes.

Seismic Hazard :

The seismic hazard map of India was updated in 2000 by the Bureau of Indian Standards (BIS). Apart from the merging of Zones I and II, there are no major changes in the new hazard map with respect to the state of Rajasthan, as compared with the previous 1984 BIS map. Western parts of the districts of Barmer and Sirohi as well as northern sections of Alwar district lie in Zone IV, where the maximum intensity could reach VIII (MSK). The remaining areas of Barmer and Sirohi districts, as well as the districts of Bikaner, Jaiselmer and Sirohi lie in Zone III. The north-eastern districts of Jhunjhunu, Sikar, Bharatpur and the rest of Alwar also lie in Zone III. The maximum intensity expected in these areas would be around MSK VII. The rest of the state, including the capital, Jaipur, lie in Zone II, where the maximum intensity expected would be around MSK VI. It must be noted that BIS estimates the hazard, based in part, on previous known earthquakes. Since the earthquake database in India is still incomplete, especially with regards to earthquakes prior to the historical period (before 1800 A.D.), these zones offer a rough guide of the earthquake hazard in any particular region.

Largest Instrumented Earthquake in Rajasthan :

15 August 1906 - Thar Desert, Rajasthan, Mw 6.2 (1)
25.00 N, 71.00 E, OT=22:11 UTC (1) 
This event was located along the India-Pakistan border, in the vicinity of Janpalia, Rajasthan which is located north-northwest of Bakhasar. It was felt widely along the Indo-Pakistan border, Sindh, and Gujarat. It was also felt for several seconds in Rajputana, Jodhpur, Ahmedabad and around the Gulf of Khambat and at Mirpur in Pakistan. 

Disaster risks in Rajasthan are further compounded by increasing vulnerabilities related to changing demographics and socio-economic conditions, unplanned urbanization, development within high-risk zones, environmental degradation, climate change, geological hazards, epidemics and pandemics. Clearly, all these contribute to a situation where disasters seriously threaten India’s economy, its population and sustainable development.