Earthquakes Recorded Southwest of Trinidad. No Tsunami Threat

Preliminary and reviewed earthquake solutions for the Tuesday 28th January 2020 quakes in the Gulf of Paria by the USGS, UWI SRC and FUNVISIS.

Shortly after midnight, at 12:02 AM, a small, minor earthquake struck in the Gulf of Paria, just west of Cedros and northwest of Icacos. 12 minutes later, at 12:14 AM, another minor earthquake struck in a similar location. Both of these quakes, reported by FUNVISIS, were foreshocks, leading up to a (preliminary) Magnitude 5.3 earthquake 10 minutes after.

No damage was reported across the affected areas as of 2:00 AM.

This larger, moderate earthquake was reported felt across much of Western Trinidad with light shaking in Southwestern Trinidad and weak shaking in Northwestern Trinidad. You can submit felt reports to the University of the West Indies Seismic Research Centre or the United States Geological Survey.

There is no tsunami threat.

There are four conditions necessary for an earthquake to cause a tsunami:

  1. The earthquake must occur beneath the ocean or cause material to slide in the ocean.
  2. The earthquake must be strong, at least magnitude 6.5.
  3. The earthquake must rupture the Earth’s surface and it must occur at shallow depth – less than 70 KM below the surface of the Earth.
  4. The earthquake must cause vertical movement of the seafloor (up to several meters).

None of these conditions occurred.


12:02 AM Foreshock – Magnitude 3.4 Earthquake

Preliminary Earthquake Solution for M3.4 Earthquake (Foreshock) at 12:02 AM Tuesday 28th January 2020 according to FUNVISIS.
Preliminary Earthquake Solution for M3.4 Earthquake (Foreshock) at 12:02 AM Tuesday 28th January 2020 according to FUNVISIS.

At 12:02 AM, Tuesday 28th January 2020, a minor Magnitude 3.4 (MW) earthquake struck in the Gulf of Paria, 26.3 kilometers northeast of Cedros. Earthquakes of this magnitude are generally not felt, particularly due to the distance away from population, though at a shallow depth of 9.7 kilometers.


12:14 AM Foreshock – Magnitude 3.8 Earthquake

Preliminary Earthquake Solution for M3.8 Earthquake (Foreshock) at 12:14 AM Tuesday 28th January 2020 according to FUNVISIS.
Preliminary Earthquake Solution for M3.8 Earthquake (Foreshock) at 12:14 AM Tuesday 28th January 2020 according to FUNVISIS.

At 12:14 AM, Tuesday 28th January 2020, a minor Magnitude 3.8 (MW) earthquake struck in the Gulf of Paria, 27.6 kilometers northeast of Cedros. Earthquakes of this magnitude are also generally not felt, particularly due to the distance away from population, though at a shallow depth of 9.7 kilometers.


12:24 AM (Preliminary) Mainshock – Magnitude 5.3 Earthquake

Preliminary Earthquake Solution for M5.3 Earthquake (Preliminary Mainshock) at 12:24 AM Tuesday 28th January 2020 according to UWI SRC.
Preliminary Earthquake Solution for M5.3 Earthquake (Preliminary Mainshock) at 12:24 AM Tuesday 28th January 2020 according to UWI SRC.

At 12:24 AM Tuesday 28th January 2020, a preliminary Magnitude 5.3 (Md or Mt) earthquake occurred 10.2 kilometers northwest of Icacos, Trinidad, and 13.5 kilometers west of Cedros, Trinidad.

This event occurred at a shallow depth of 10 Kilometers. This information (above) is preliminary from the U.W.I. Seismic Research Centre, the authority for seismic and volcanological information in the Eastern Caribbean. Quake parameters such as location, depth, and magnitude may change upon review from a seismologist at the SRC.

Reviewed Earthquake Solution for M4.8 Earthquake (Preliminary Mainshock) at 12:24 AM Tuesday 28th January 2020 according to USGS.
Reviewed Earthquake Solution for M4.8 Earthquake (Preliminary Mainshock) at 12:24 AM Tuesday 28th January 2020 according to USGS.

The United States Geological Survey registered this quake as a reviewed magnitude 4.8 (mb) at a notably different location, further north and west, and significantly deeper, at 40.5 kilometers, from the SRC’s solution.

Preliminary Earthquake Solution for M4.7 Earthquake (Preliminary Mainshock) at 12:24 AM Tuesday 28th January 2020 according to FUNVISIS.
Preliminary Earthquake Solution for M4.7 Earthquake (Preliminary Mainshock) at 12:24 AM Tuesday 28th January 2020 according to FUNVISIS.

The Venezuelan Foundation for Seismological Research registered this quake as a preliminary magnitude 4.7 (MW) at a similar location to the USGS but differs from the UWI SRC’s solution, further north and west, at a depth of 9.7 kilometers.

Note that across the globe, different seismic monitoring agencies use different methods, or several methods, for processing earthquake parameters. Each method has its limitations and will likely produce different results within the ranges of the uncertainty of that data. This is generally accepted within the scientific community.

Based on the location and depth of the reviewed solutions of this earthquake, it likely occurred in seismic zone 3, where a complex network of main faults and its conjugate faults interact in the Gulf of Paria as the Los Bajos and Warm Springs faults from on-land Trinidad meets the El Pilar fault. Here, seismicity is fairly high, with quakes generally shallow to rarely intermediate depth, up to 50 kilometers deep generally, and at times, up to 140 kilometers deep.

The UWI SRC has stated during a Q&A of the earthquake swarm between January and February 2018, faults in the Gulf of Paria are capable of generating a magnitude 6.5 or greater earthquake.

Within 10 kilometers of the epicenter of all recorded earthquakes as of 1:00 AM, earthquakes up to magnitude 4.8 have occurred since 1950. These quakes occurred along the several strike-slip and conjugate normal faults as part of the fault network in the Gulf of Paria. The strongest quake, in this area, occurred during the January and February 2018 Seismic Swarm, at Magnitude 4.8 on January 26th, 2018.

Earthquakes *cannot* be predicted – meaning the precise time, date, magnitude, depth, etc. cannot be known ahead of time based on current research and technology.

Generally, across the Eastern Caribbean, a seismically active area, earthquakes of this magnitude, up to M8.0 and greater, are possible and this statement has been repeated by seismologists at the U.W.I. Seismic Research Centre for decades.

Each year, over 2,200 seismic events are recorded in the Eastern Caribbean. On average, the Eastern Caribbean has seen a pattern of major (M7.0-M7.9) quakes every 20 to 30 years. That pattern has stayed true. The last major (M7.0-7.9) quake occurred north of Martinique in 2007. 

Historical patterns indicate great earthquakes (M8.0+) on the Richter Scale have occurred every century or so in the region. The probability of another event at that level is high since the last >M8.0 earthquake occurred in 1843.

Now is the time to create or go over your earthquake preparedness plan and know what to do during, before and after an earthquake. See here for more details.

Facebook Comments