Worst recorded measured 7.9

Although many claim that it was the worst to affect the area in several decades, data shows that this country was rocked by an earthquake measuring 7.9 on the Richter scale on October 21, 1766. This was the largest tremor on record to ever directly affect the island. Despite the fact that no deaths were reported or documented, that earthquake destroyed San Jose, Trinidad’s capital at the time.

Records also show that there have been eight other earthquakes with a greater magnitude than 6.0 between 1899-1952 within 250 km of Trinidad. One event, which took place on January 23, 1910, had a magnitude of 7.2, which would make it the second largest earthquake to affect the country.

An earthquake on September 20, 1825 with no recorded magnitude was said to have affected all the buildings in the Port-of-Spain area. Buildings at the time were mainly two storeys structures made with unreinforced masonry.

Another which occurred in 1954, had a magnitude of less than 6.5 and claimed one life and injured many others.

However not all large magnitude earthquakes are destined to be destructive. It depends on the depth of the focal point.

During March of 1988 for instance, there were a series of earthquakes which had a magnitude of 7.2.

The reason they were not as devastating was that most at that strength tend to be because its focal point was 56 km in depth and it was at some distance from Trinidad and Tobago.

However, within recent times there have been some devastating tremors. Almost ten years ago, on April 22 and July 9, 1997, an estimated TT$18 million in damage was suffered when earthquakes measuring 5.9 and 5.7 respectively hit the country.

Extensive damage was suffered in Tobago as the quakes’ focal points were approximately 28 km and less than 5 km, while their epicentres were 30 km and 15 km away from Scarborough.

Even more recently, there was an earthquake on October 4, 2000, with a magnitude of 5.9. No damage was reported.

The Structural Engineers Association of California (SEAOC) has ranked TT in Zone 3 which represents “a zone of relatively high seismicity based upon a seismic risk map of the country.” The largest possible earthquake which may occur in a 100 km radius of Trinidad and Tobago is 7.0, experts say.

Although the extent of the damage on Friday is yet to be determined, the event did wreak havoc on buildings and lives around the country. Houses collapsed, several building sustained structural damage, persons were injured and one man was reportedly killed.

Some schools had to be closed and several banks and other institutions remained closed, stalling commercial activity for the day.

Friday’s tremor and aftershock at about 2.23 pm caused power failures in several areas along the East- West corridor, Marabella and Tobago. Attempts to restore electricity were foiled by the 5.1 magnitude after shock later in the day.

Taps went dry in North, Central and South Trinidad as the power interruption affected the water supply to these areas.

Piarco Airport had to be closed causing a delay in flights. Cell towers were placed out of alignment causing failure on the bmobile cellular network.

Officials of the Office of Disaster Preparedness and Management (ODPM) said regional corporations will continue to assess damages and attempt to restore order where possible.