Can you tell me of your experience in an earthquake?

Have you felt an earthquake? If so please tell your experience.?

• Answer:

  The big real story on Tsunami day. It was about 6.30 am when the telephone bell rang. It was a call from retired executive engineer from Tamilnadu electricity board. He asked me, if my earthquake instrument sensed any warning. I said that “No, however; I will adjust the sensitivity and see”. He said that he could see cups & saucers moving on the table. Around the same time, my daughter-in-law came from the second floor and said that she felt her cot shake. I was adjusting the sensitivity of my instrument fixed in my hall. Again another phone call from a former project engineer of M/s Enfield, India; from Annanagar. He said he was able to see water in the bubble top water filter shaking peculiarly. Most of my friends used to call me to get the clarifications on earthquakes. I replied “I am adjusting the sensitivity of my instrument, I will contact you later”. My instrument then started sensing the waves and it raised an alarm sound. But there was no ground motion felt by us. As, there was no ground shaking I have disconnected the sounding device and I was observing the flickering of the light in the quake alarm. Since, the frequency of the earthquake (0.5 to 15 Hz) is lower than the capacity of our vision I was able to see the flickering of the bulb. Although, I have 4 early warning instruments in my house (two imported from U.S.A. and the other two were designed by me), only my latest simplified design was adjusted to sense the earthquake on that day. The warning signal stopped at about 6.42 A.M I.S.T. So the total warning time was 12 minutes. I never heard in the history of earthquake that the signal lasted for 12 minutes. Generally, earthquake produces shakings for a few seconds to one or two minutes only. The earthquake shakings sensed by my quake alarm for 12 minutes is very high. I was upset for a few minutes. I just thought of the concept of Richter scale. If the amplitude of shaking is low and the time of sensing was for very long time it is also equal in magnitude if the amplitude is high and the shaking is for shorter time. Therefore, I came to a conclusion that the magnitude of the earthquake sensed by my instrument is very high and should be from far away distance. As my eye was operated, I was unable to move out of my house. My another friend called me over phone and asked about its effect. I explained him that the sea water may rise to a great height. I brought the Xerox copies of earthquake behaviours from USA library. In the book named “ earthquakes” written by Mr Bruce A Bolt, it was clearly mentioned what should be and should not be done before, during and after earthquake. It reads like this “Stay away from beaches and waterfront areas where Tsunami could strike even long after the shaking has stopped”. That day was also full moon day. The seismic activities will be more on that day. Therefore I informed T.V. to broadcast the alert message at 6.45 a.m. itself. They ignored my warning. People were unaware of the changes that took place before the earthquake that is barking of police dogs as reported by the Chennai police department; the water receded in the sea shore before the Tsunami attack at Kanniyakumari. Water in small tanks and ponds near Nagappattanam spilled out and the water became muddy. The fisher men in Malaysia got heavy catch of fishes 2 days before Tsunami attack.