At 5:35AM Monday 15th April 2019, a Magnitude 4.0 (MD) earthquake occurred 73.6 Kilometers East of Fort-de-France, Martinique and 115.6 Kilometers NE of Castries, St. Lucia. This event occurred at a shallow-moderate depth of 42.0 Kilometers. This information was reviewed by an analyst at the U.W.I. Seismic Research Centre.
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 uncertainty of that data. This is generally accepted within the scientific community. The French Seismological Central Office (BSCF) has also recorded this earthquake as a magnitude 4.0, with similar parameters to the Seismic Research Centre.
Related: Earthquake Magnitude & Intensity
This event was widely reported felt across parts of Martinique with maximum MMI values of III, indicating weak shaking. This event occurred in a highly seismically active area. Here, the Mercurius Fracture Zone subducts under the Caribbean Plate. Earthquakes in this area are generally shallow-moderate, ranging between 0-80 kilometers. Earthquakes up to magnitude 6.5 have occurred in the past (May 21st 1946), with the strongest in recent times occurring on February 2nd 2017, a magnitude 6.0.
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, in the Eastern Caribbean, a seismically active area, earthquakes of this magnitude, up to M8.0 and greater, are possible in area, 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.
Related: Earthquake Safety
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.