HYDERABAD: After 122 micro-earthquakes of less than 1 magnitude were registered at the six seismic stations located in and around Borabanda and a similar one off-earthquake in Jubilee Hills, experts at the National Geophysical Research Institute (NGRI) say the swarm of micro-earthquakes are ‘dead in the rocky terrain’ of the city. Before a micro-earthquake was recently felt at Jubilee Hills a few days back, Borabanda recorded 122 micro-earthquakes between October 21 and November 8. “The micro-earthquakes at Borabanda were last recorded on November 8. The Earth movement is dead now and there is no need to worry,” said Dr Srinagesh Davuluri, Chief Scientist, Seismology Observatory, NGRI.
However, seismic stations located at NATCO school and five other places will continue to record the Earth activity for a month to further examine the faults and fractures of the earth. “If we look at Jubilee Hills particularly, there were more than 400 micro-earthquakes recorded there in the year 1994. But, this time it has been around Borabanda. We will have to examine further faults and fractures in that area,” said the chief scientist.
Many buildings in the city, not earthquake resistant
After examining the recent swarm of seismic activity, researchers and scientists point that even the minimum precautions to be taken in constructing buildings according to Bureau of Indian Standards (BIS) are not followed. “Almost 90 percent of buildings do not follow the IS 456-2016 code for plain and reinforced concrete and IS 1893- 2016 code of seismic design and structure,” observed Prof Ramancharla Pradeep Kumar, Head of Earthquake Engineering Research Centre, IIITH.
The present condition of earthquakes triggered due to rainfall is not just the reason but a series of rock blastings that took place decades ago to expand the city which now houses the IT corridor and all other surrounding areas is a reason for the tremors, he added. “When the whole rocks at Gachibowli were blasted to expand the city two decades ago, there were similar sounds that occurred. People need to take necessary precautions to be psychologically strong and invest a little more in strengthening buildings,” suggested the professor.
Hydro Seismicity triggered micro-earthquakes
According to NGRI, the recent
micro-earthquakes were triggered due to Hydro Seismicity
Hydro Seismicity is a condition wherein earthquakes are caused due to excess water inflow into already built up pressure inside the fractures and faults inside the Earth causing hollow sound
Such Earthquakes can either be felt or not felt depending on the magnitude recorded on the Richter Magnitude Scale which is usually less than 1
Earthquakes triggered due to Hydro seismicity is historically common which is generally during the months of September to Nov