10:01 AM – Moderate Earthquake Recorded South of Dominica. Event Widely Felt. No Tsunami Threat.

At 10:01 AM Wednesday 8th January 2020, a preliminary Magnitude 5.2 (Md or Mt) earthquake occurred 23 kilometers southeast of Roseau, Dominica, and 66 kilometers north-northwest of Fort-de-France, Martinique.

This event occurred at an intermediate depth of 123 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.

10:00 AM January 15th 2020 Update: The UWI SRC has issued another preliminary update at a slightly more north and east, at 15.23°N and 61.16°W with a lower magnitude of 5.0 and deeper depth of 151km. This information is still preliminary and may change after being processed by a Seismologist.

This earthquake was reported felt in St. Vincent, St. Lucia, Martinique, Dominica, and Guadeloupe. 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.

The United States Geological Survey registered this quake as a reviewed magnitude 5.1 (mb) at a deeper depth of 144 kilometers, slightly further north and west from the SRC’s preliminary solution. The French Seismological Central Office also recorded this quake as a magnitude 5.1.

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 this earthquake, it is tectonic in origin and occurred within the Caribbean Plate, above the subducting South American plate to the east.

Within 20 kilometers of the epicenter of the main earthquake, since 1960, quakes have generally registered below magnitude 6.6, generally between 100 km and 200 kilometers depth, though weaker and shallower quakes have been recorded.

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