UWI Seismic Research Centre: A 3rd explosive eruption is currently underway. It began around 6:35 pm
(By Ernesto Cooke) – Vincentians should prepare for more explosive eruptions and heavy ashfall as ongoing explosive eruptions and periods of significant output of ash above the volcano Continue.
The first explosive eruption of La Soufriere since it rumbled back into life in November 2020 was recorded at 8.41 am Eastern Caribbean Time on Friday 9th April.
Geologist Richard Robertson said at 2.45 – continuous pulsing of ash, gas and steam feeding each other created a large explosion sending a plume of ash up to 51 000 feet into the atmosphere.
The plume of ash, for the first time, was seen in the capital city Kingstown.
The volcano has cleared a path to release more gas and steam, more breaking of rocks from the 79 dome is still ahead, Robertson said.
The geologist said the ash plume is rocks that have been pulverized, and the further away it gets from the volcano it becomes really fine.
“ At some time that ash plume would eventually fall to the ground as it spreads in the atmosphere over long distances, it will not cause you to die, but could create health issues especially if you suffer from respiratory ailments”. Robertson stated.
The geologist noted that most of the ash is expected to go offshore, with large swaths going to the east and west.
People in Barbados may receive more ashfall than persons living in the south of St Vincent.
In the case of SVG on the Leeward end as far south to Barrouallie and Colonarie on the Windward side”, we expect significant ash, he said.
Robertson said a volcano such as La Soufriere doesn’t produce lava flows because the magma is so sticky that it forms a dome by the time it reaches the surface.
“what I expect to see in this period of eruptions is more explosive venting episodes of ash, you may have flows down the mountainsides, but we don’t call it lava flows; it is pyroclastic or gravity current “.
A pyroclastic flow is a fast-moving current of hot gas and volcanic matter that flows along the ground away from a volcano at average speeds of 100 km/h but can reach speeds up to 700 km/h.
Robertson said when the volcano releases the ash in an explosion, materials go along with it; however, the energy they came out with can’t be sustained and fall back and down the mountainsides; that is why we evacuate people before an eruption, pyroclastic flows are deadly, he said.
“ We can expect these materials to surface in places like at Rabbacca and Richmond; you ought to know that they destroy everything in its part”.
Robertson said that those in the RED ZONE who decide to stay now is your cue to leave.
