At 1:10 PM, Saturday 20th March 2021, a (preliminary) light Magnitude 4.1 (Mw) earthquake occurred approximately 31.6 KM SSW of Güiria, Venezuela, 45.8 KM SW of Macuro, Venezuela, 89.9 KM WSW of Port of Spain, Trinidad and Tobago. This event was located at 62.470°W and 10.240°N, at a depth of 11.2 Kilometers.
This information (above) is preliminary from the Venezuelan Foundation for Seismological Research (FUNVISIS). A solution has not been posted by the U.W.I. Seismic Research Centre, the authority for seismic and volcanological information in the Eastern Caribbean. This information may change when additional data is processed by a seismologist.
The event was not reported felt across Trinidad. You can submit felt reports to the University of the West Indies Seismic Research Centre.
There is no tsunami threat.
There are four conditions necessary for an earthquake to cause a tsunami:
- The earthquake must occur beneath the ocean or cause material to slide in the ocean.
- The earthquake must be strong, at least magnitude 6.5.
- 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.
- The earthquake must cause vertical movement of the seafloor (up to several meters).
None of these conditions occurred.
Note that different seismic monitoring agencies use different methods, or several methods, for processing quake parameters across the globe. Each method has its limitations and will likely produce different results within the ranges of the data’s uncertainty. This is generally accepted within the scientific community.
Based on the seismic event’s calculated location, this quake occurred in seismic zone 3, within the Gulf of Paria
The Gulf of Paria is yet another very faulted, seismically complex area surrounding Trinidad. At this zone, the extension of the Los Bajos fault from southwestern Trinidad, and the Warm Springs Fault from Central Trinidad meets the El Pilar fault. This complex network of faults also includes small, conjugate or perpendicular faults.
High levels of seismic activity occur in this zone, with both shallow and moderate depth earthquakes, generally remaining less than 50 kilometers depth. The UWI SRC has stated during a Q&A of the earthquake swarm between January and February 2018, this location is capable of generating a magnitude 6.5 or greater tremor.
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 quakes (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.