Showing posts with label earthquake. Show all posts
Showing posts with label earthquake. Show all posts

28 September 2013

Tremors felt at Tiruvannamalai



Tiruvannamalai District experienced earth tremors on Thursday morning, September 26th, after a gap of nearly 25 years, according to the Centre for Disaster Mitigation and Management, VIT University, Vellore. 

Vellore and Tiruvannamalai Districts have become seismically-active since 2002 and they have been reclassified into zone 3 (prone to quakes with up to 6.9 magnitude) from zone 2 earlier (up to 4.9 magnitude). 

Last Thursday at Tiruvannamalai, residents of Pudu Theru (i.e. Theru = Street), Pey Gopura Theru, Muthuvinayaga Theru and Mathalangula Theru; came out of their homes after the vessels in their houses fell down at about 8.20 a.m., as they feared more serious tremors. No damage to property or life has been reported. Residents returned to their houses only after ascertaining that there were no aftershocks. 


Thiruvoodal Theru leading to Pey Gopura Theru


 
The Indian Meteorological Department reported the Tiruvannamalai earthquake to measure 3.3 on the Richter scale and lasted for about three to five seconds. The epicentre of the Tremor is suspected to be in the Polur and Tiruvannamalai region, where an existing fault (planar rock fractures) passes from Salem to Tiruvallur. 

Earth tremors are a common phenomenon restricted to local conditions due to the readjusting of faults. In this respect around 105 tremors have occurred in Tamil Nadu in the last 200 years, with the majority measuring less than a magnitude of 5. Only a few of the earth tremors had a magnitude of more than 5; which included an earthquake in Coimbatore in 1900 (magnitude of 6) and one off the shores of Pondicherry in 2001 (magnitude 5.6). There are estimated to be around 286 fractured faults in Tamil Nadu, of which only around 47 have been found to be active. 

Tiruvannamalai District has only witnessed five tremors in recorded time. The first major one recorded was in 1822 at Vandavasi with a magnitude of 5, and later between Polur and Tiruvannamalai with a magnitude of 5. The same region witnessed another tremor in 1984 that had a magnitude of 3.3. 


[Information compiled from The New Indian Express]

26 March 2007

Area's seismic past


An undocumented inscription has been recently found on the compound wall of the fifth prakaram, in front of the Elephant Shed at the Arunachaleswarar Temple, which throws light on the seismic character of the region.

A rectangular stone on which a Tamil inscription is engraved is part of the compound wall. The first three lines of the inscription reads: "Prabava varusham aadi matham 16-il bookambamakayil mathil adimattamaga vizhunthu pokayil." Which states that the compound wall completely fell down due to an earthquake on the 16th of the Tamil month Aadi in a Prabhava year.

The last three words of the inscription starting from the half of the third line is somewhat ambiguous, but has something to do with the reconstruction of the wall. Experts have said that the rudimentary style of writing of the inscription suggests that it may be around four hundred years old (i.e. early part of the 16th Century).

There is no mention of this inscription in previous books relating to inscriptions at Arunachaleswarar Temple, thus it is believed to be especially important in that it undermines all previous assumptions of seismic activity in this region.



Though the year in which the tremor shook the Temple City has been mentioned in the inscription as 'Prabhava', first of the 60-year cycle in Shalivahana calendar, it could not be clearly determined in which Prabhava year it was supposed to have happened.

Pandurangan, a 94-year-old Tamil pundit, closely associated with Temples and their traditions, said that he had heard about an earthquake that hit Tiruvannamalai from his ancestors. But he never came across any reference about this inscription in any of the books that documented the temple inscriptions. According to him, the quake could have occurred over 400 years ago because if it was within 200 years then he would have heard more about it from his elders. Experts have concurred with the Pundit, and all agree that the tremor must have happened around 400 years ago.