By: Staff Writer
September 14, 2021
Last week Thursday a 5.2 magnitude earthquake rocked the coast of St Vincent and the Grenadines, no deaths or injuries reported.
The Trinidad-based Seismic Research Centre (SRC) of the St. Augustine campus of the University of the West Indies (UWI) said that an earthquake occurred south of St. Vincent and the Grenadines (SVG). It was located at 13.02°N and 61.28°W with a magnitude of 3.2 and depth of 166.5km. This event was reported as felt.
SVG is just recovering from the scary situation of the La Soufriere volcano erupting in April of this year that was precipitated by several earthquakes in the SVG area.
In fact, the last 12 months has been a very busy time for seismic activity in the Caribbean as Haiti was devastated in August by a 7.2 magnitude quake, larger than the deadly 2010 7.0 quake that killed thousands of Haitians, leaving the country in ruins.
Haiti never fully rebounded from the 2010 earthquake as many of its infrastructure was never fully rebuilt, if at all.
There has also been seismic activity off the coast of the British Virgin Islands and Antigua and Barbuda in January of this year, adding to the other tremors that were occurring from late last year, too numerous to count.
The SRC does not have a firm answer as to why there were so many quakes in the peaceful waters of the Caribbean, but they have note with the SVG earthquakes that coincided with the La Soufriere eruption is that the Caribbean will continue to have seismic activity. So be prepared.
Scientists however have pointed to the possibility that oil drilling is behind the increase in earthquakes in general. Considering that Guyana has started drilling for oil and historically there have been oil drilling in Trinidad and Tobago, gives us reason to believe that this relationship may be true. Of course, how can you poke a hole in the belly of Mother Nature and not have any consequences?
A National Geographic report stated as much, that water left over from oil and natural gas production may strengthen the magnitude of earthquakes in states like Oklahoma and Kansas and dense, salty water pumped deep into the Earth is putting stress on small, hidden fault lines scattered throughout oil-producing regions. The salty water that companies inject into the Earth can be denser than the water initially extracted.
Ryan Pollyea, a Virginia Tech hydrologist and study author, looked at two oil-rich formations (zones of trapped oil or gas) in Oklahoma namely the Mississippi Lime and the Arbuckle. Thanks to technological advances, both formations saw an oil boom from 2010 to 2015. The problem, Pollyea said, was that wastewater pumped from the Mississippi Lime was denser than the water in the seismically active deep rock formation where it was injected and lead to increased stress on the region’s faults.
Over that same five-year time period, the number of earthquakes of magnitude 2.5 or higher went from zero to more than 300. The team found that the hypocentres, the deep point of origin for earthquakes, were also getting deeper, about half a kilometre per year and where there was also a higher proportion of high magnitude earthquakes. By sinking progressively deeper, the water exerts more pressure on faults and increases the chance of triggering a high magnitude earthquake, Martin Chapman, seismologist at VA-Tech also says.
As we drill for oil, we must be prepared to come with the consequences. The Bahamas failed to find oil in their waters, but still drilled an exploratory well last year, which may have done some damage to the tectonic plates.
Hurricanes we can handle a bit. We know about the high winds and flooding. Earthquakes are new to this generation of Caribbean people.
The Caribbean leadership outside of the SRC have little to no plans on how to deal with earthquakes, despite having seen what happened in Haiti this year and even back in 2010.
Now that scientists are being armed with more information, what will the Caribbean do? Most certainly we cannot ask a poor country like Guyana to stop drilling for oil when they are the only country in 2021 to post a budget surplus and make it out of the COVID-19 pandemic financially in better shape than other Caribbean country, which was mainly due to oil revenues.