In order to reduce the damage caused by earthquakes, scientists in New Delhi have adopted the Seismic Hazard Microzonation technique that forms a significant tool in risk evaluation and mitigating the disastrous impact of earthquakes.
The damage to the life and property caused by an earthquake can be greatly reduced by adopting engineering approaches for suitable earthquake resistance construction, strengthening of existing structures, and proper land use planning.
"This is one of the ways of finding out the hazard, which an earthquake causes. During an earthquake many buildings where people live are affected. If we can find a way that what is the hazard to a building then we try to reduce that hazard that is Seismic Microzonation," said AK Bhatnagar, additional director general of Meteorological Department.
Seismic Hazard Microzonation is an important tool to generate parameters for site specific structural designs, land use plans and disaster mitigation and therefore Seismic Hazard and Risk Microzonation (SHRM) forms a significant tool in risk evaluation and mitigating the disastrous impact of earthquakes.
Seismic Hazard and Risk Management is a multi-criteria based on a given domain into small units of likely uniform ground response in terms of Hazard level like peak ground acceleration (PGA) peak ground velocity (PGV) & peak ground displacement (PGD), nature like fissuring, liquefaction, slope deformation and induced flood, fire and damage pattern or risk.
Earthquakes are the most dreaded natural disasters especially due to their intrinsic nature to unleash devastation instantaneously in large area without leaving much scope for prevention of the hazard after the occurrence of the event.
Surveys of earthquake-affected areas reveal that apart from physical damage to terrain and man made structures; the impact of an earthquake becomes part of the social psyche.
Hence, compared to other natural disasters, earthquakes calls for better pre-disaster prevention and preparedness rather than resorting to fateful measures of Rescue Relief and Rehabilitation.
Earthquake Risk Evaluation plays a major role in identifying the potential consequences of an earthquake, both in relation to existing structures as well as in the planning and locating new facilities.
AK Bhatnagar further added that by adopting this technique one could save human lives at the least.
"This is a way that we know that particular area is prone to hazard and can be precisely determined in terms of the parameter that can be used in building design and we can make your building safer to the extent that they don't collapse totally so you can save human lives at least," said Bhatnagar.
The quantitative evaluation of risk by providing a rational basis for risk reduction and reorienting current strategies prevalent strategies prevalent in this country can shift the focus from highly expensive post disaster and relief operation to a cost effective advanced action plan.
More than 650 earthquakes of M6.0 have been recorded in Indian territory during past century. Indeed, 4 great earthquakes of magnitude 8.0 have rocked the Himalayan belt since 1897, each having rapture length of 200-300 km.