Lahar deposit in Sandy Bay Village, St. Vincent, northeast of the La Soufrière Volcano. (Jawid Collins, UWITV)
|Present La Soufrière Alert Level:||ORANGE||There is a highly elevated level of seismic and/or fumarolic activity or other unusual activity. An eruption may begin with less than twenty-four hours’ notice.|
According to the latest scientific advisory from the University of the West Indies Seismic Research Centre (UWI SRC), seismic activity at La Soufrière, St Vincent has remained low since the tremor associated with the explosion and ash venting around noon on 22nd April. In the last 24 hours, only a few long-period, hybrid and volcano-tectonic earthquakes have been recorded, and there was no further tremor. The volcano continues to be in a state of unrest.
Volcano-tectonic (VT) earthquakes represent the brittle failure of rock – similar to that of tectonic quakes that occur along tectonic faults. Long-period (LP) earthquakes are caused by cracks resonating as magma and gases move toward the surface. As the name suggests, a hybrid earthquake is somewhat a mixture between a VT and an LP. They tend to have impulsive starts but also contain a significant amount of low-frequency signals. They are thought to represent magma making its way to the surface at shallow depths and are often associated with periods of rapid dome growth.
Latest satellite imagery of the La Soufrière Volcano crater shows little change since the initial explosive eruption. The material within the crater is showing more texture, likely due to the heavy rainfall. The volcano is still in a state of unrest, and explosions and secondary hazards like lahars (mudflows) can still occur without warning.
According to the UWI SRC, the volcano continues to erupt. Explosions with accompanying ashfall, similar to or larger, can occur with little or no warning impacting St Vincent and neighboring islands.
The alert level remains red. The National Emergency Operations Center continues to be fully functional operating on a twenty-four-hour, around-the-clock basis. NEMO will continue to provide regular updates as they continue to monitor the Volcano.
Official information will originate from St. Vincent and the Grenadines National Emergency Management Organization and the University of the West Indies Seismic Research Center.