Seismologist at the University of the West Indies (UWI) Seismic Research Centre, Dr Joan Lutchman, has confirmed that the two earthquakes which hit Trinidad and Tobago on Monday night were linked to August's 6.9 magnitude earthquake.
The first earthquake was felt at 11.33 pm, measured 5.1 and was located at a depth 10 km and was felt 88 km west south-west of Port-of-Spain and 91 km west north-west of San Fernando.
UWI's SRC said the second quake, which occurred four minutes later, had a magnitude of 4.2 and was also located at a depth of 10 km.
There was no loss of property or damage recorded following Monday's earthquakes.
Speaking to the T&T Guardian in a telephone interview a few moments ago, Lutchman said the latest earthquakes, which measured 5.1 and 4.2 in magnitudes, were related but were not aftershocks of the August 21 earthquake. She explained that the recent earthquakes occurred because of the settling of the active earthquake zone in the Gulf of Paria.
Asked whether the two earthquakes were early signs of the anticipated mega-quake predicted for this region, Lutchman responded, "No. At this time, we would not say that, even though we are certain we are due for a big earthquake soon." The Caribbean region has not recorded a mega-quake since 1766 and seismologists say one is due.
Lutchman said after the August 21 earthquake, 60-plus aftershocks were recorded by the UWI Seismic Centre. The strongest of these was 6.1 in magnitude on August 22.
"Unlike when we have shallow earthquakes, the aftershocks come in. We expect that in a case like this, as the zone settles we would see the bigger earthquakes over a longer timeframe," she explained.
Saying the entire Gulf of Paria zone has been active since January, Lutchman noted, "The earthquakes from Monday are not in the same zone as the last one so I would not say they are aftershocks. They have occurred as a result to the area settling. The entire Gulf of Paria zone has been busy. On January 26 we had a number of these Gulf of Paria earthquakes not where the big one occurred on August 21."
She said the entire Caribbean region was in a period of activity.
In preparation for the mega earthquake which is due to hit, Lutchman said the Government must begin to do a critical assessment of all infrastructure. She also said the homeowners must also put systems in place to secure their homes.
Meanwhile, past president of the National Building Code Committee Shyankaran Lalla also said preventative measures must be taken to safeguard lives in the event of a mega earthquake.
"I want to call on the Government to give serious consideration for the critical assessment of our infrastructure so we can prioritise areas of need and develop accordingly. I want to remind the Government that this country has no legally enforced building codes and I once again call for the adoption of the (International Code Council) ICC codes," he said.
Lalla also said there must be enforcement of specifications when building is done in flood-prone areas.