The first seismological observatory in the country was established in Alipur (Calcutta) in 1898. Subsequently, two more observatories were established at Colaba (Bombay) and Madras in 1899 ( later shifted to Kodaikanal)

The national network was further expanded by the India Meteorological Department (IMD) In December 1967, an observatory was established at the National Geophysical Research Institute (NGRI), Hyderabad.

The IMD is the national organisation maintaining the national seismological network, providing information on earthquakes to the Government and the media.

Institutions like the Bhabha Atomic Research Centre (BARC) and the NGRI also carry out earthquake monitoring and research.

Several other institutes and universities also got involved with these studies during the later years.

The Department of Science and Technology (DST), Govt. of India initiated a multi-institutional and multidisciplinary programme in 1982, directed mainly towards earthquake hazard mitigation.

The ultimate goal of the DST’s programme is to save lives and properties through research efforts by pooling of resources and manpower

Earthquake studies have acquired momentum, particularly after the recent earthquakes at Uttarkashi, Latur and Jabalpur

Ever since, seismic hazard assessment and risk analyses, updating the seismic zonation maps and engineering seismology have gained higher priority in seismological research

Understanding the crustal structure and earthquake processes and estimation of recurrence interval are other priority areas of research

Most of the DST’s ongoing efforts are directed towards understanding the seismicity of some of the major tectonic provinces of the country

These include the NW Himalaya, NE India, and parts of the Indo-Gangetic plains in the north

Delhi area has also received much attention

The peninsular shield is another region of interest

Major research programme in the peninsular shield evolved after the Latur earthquake.

Existing seismic stations are being upgraded and new stations are being added

About 15 research organisations are participating in the research programmes

GPS campaign involving installation of many permanent stations

Projects on seismotectonics, paleoseismology, seismic hazard evaluation, seismic tomography, borehole studies and crustal deformation

Shield seismicity: Major facilities

Upgradation of 20 existing seismological observatories of IMD

The Himalayan frontal arc is seismically one of the most active regions in the world

At the national level, the IMD operates and maintains 18 seismological observatories in the Himalaya and the contiguous region

The IMD also operates other observatories for special purpose studies in specific regions

Research organizations like the University of Roorkee, Regional Research Laboratory (Jorhat),Wadia Institute of Himalayan Geology, Manipur University and many others operate local observatories in different parts of the Himalaya.

The DST has launched a nationally coordinated project on the study of seismicity and seismotectonics in the Himalayan region involving several research organizations

Site response data is essential for seismic resistant design of structures.

To derive this input, strong motion accelerographs need to be in place. The first record from peninsular India was obtained     from Koyna in 1967 and that from the Himalaya in 1968.

Since 1976, the DST has been funding a strong motion instrumentation programme in the country.

About 194 strong motion accelerographs (both analog and digital) have been installed along the Himalayan frontal arc.

These facilities continue to generate useful data, particularly related to the near-field earthquake strong motion.

The Gobal Positioning System (GPS) measures the time required from an orbiting satellite to a ground receiver and converts this time to distance.

Measurements are made by a receiver on the ground, with a clock that is time-synchronized with an orbiting GPS satellite equipped with atomic clock.

The central core of the operation is the simultaneous determination of distances between a ground station and sets of four or more satellites.

The distance between a satellite and receiver is calculated by comparing the time of GPS signal reception with the time of transmission. Simultaneous measurement of the distances to four satellites is required to solve for the receiver’s position on the Earth’s surface in terms of latitude, longitude and height.

By repeating these measurements over discrete time intervals, change in station coordinates can be determined to a high degree of precision. By repeated observations and using different data processing techniques, changes between the baselines can be determined.

Understanding the seismic history of a region is an important component of seismic hazard assessment and mitigation.

Important events including earthquakes are described in many of its historic documents.

Extensive search through historic documents has provided information about many hitherto unknown earthquakes during 1200 A.D. to 1800 A.D.

Paleoseismology : A tool to date prehistoric earthquakes

Paleoseismology - the study of prehistoric and ancient earthquakes- is an emerging multidisciplinary area of research which provides insight into the behaviour of seismogenic faults

Paleoseismology develops its data base from the evidences of previous earthquakes preserved in the geological records

It utilizes techniques from various disciplines in geology and seismology besides Quaternary Dating Techniques to determine the time of occurrences and to develop recurrence models of earthquakes

The aim of these studies is to understand the spatial and temporal pattern of earlier events so that this data can be used to predict the future behaviour of the causative structures

The 1819 earthquake (M ~ 8.0) at Kutch generated a 100-km-long fault scarp that is popularly known as Allah Bund, meaning the wall of God.

Recognising the importance of this site, the Department of Science and Technology (Govt. of India), organised a field workshop in the Runn of Kutch and conducted a tour to Allah Bund in 1993

M apping the scarp morphology, trenching excavations near Allah Bund and developing age constraints are some of the studies that are in progress.