BRIDGETOWN, Barbados, July 23, 2015 (AMG) — The Seismic Research Centre (SRC) of the University of the West Indies has issued an orange alert for the underwater volcano Kick’em Jenny, after strong and sustained signals were recorded in the early hours of this morning suggesting than an eruption could occur with less than 24-hours notice.
Instruments monitoring the volcano, located 8km north of Grenada (12.3000° N, 61.6400° W), recorded strong, continuous activity between 1:25 a.m. and 3.am. Grenada, as well as St. Vincent and the Grenadines, Barbados and Trinidad & Tobago are particularly on alert.
“Signs of elevated seismicity began on July 11 and continue to present. For the period since July 11, a total of more than 200 micro and small earthquakes, of varying magnitudes, have been recorded, with the largest, prior to the strong signal, less than magnitude 3.0,” the SRC reported. “This activity is being closely monitored by the UWI-SRC and further updates would be issued as more information becomes available,” the centre said.
Speaking to the media today, Director of the Coastal Zone Management Unit in Barbados, Dr Lorna Innis, reassured residents of the island that the probability of a tsunami following the possible eruption of Kick’em Jenny was low – but not non-existent. Said Dr. Innis, the probability of tsunami generation from underwater volcanoes increased the closer the volcano’s dome was to the surface of the sea, unlike Kick’em Jenny, which is believed to be located at a depth of 180m under water.
“An eruption [of Kick ‘em Jenny] can cause a tsunami, but we are dealing with possibilities. The dome of the volcano is in extremely deep water at this stage. As the dome grows…and it grows extremely slow over decades and centuries… it moves closer to the surface of the water, and the greater the probability that when it erupts you will have a tsunami. At this point in time it is rather low as it is in extremely deep water and therefore the possibility of a tsunami is low,” she stated.
What does an orange alert mean?
At the orange alert level, the SRC recommends that the governments of Grenada, St. Vincent, Barbados and Trinidad & Tobago should advise residents of evacuation routes, and put transportation on standby to facilitate evacuation in the event of a tsunami.
Radio stations are also being advised to convey emergency messages that may emanate from the SRC, and residents are asked to monitor updates on the SRC website.
Maritime exclusion zones
Shipping vessels should stay 1.5 km from the summit of Kick’em Jenny, and non-essential shipping, such as pleasure craft, should not enter within 5 km of the volcano’s summit. An eruption, or increased activity around Kick’em Jenny, is particularly dangerous for marine vessels, since the gases released from the volcano can lower water density and cause sinkage.
Kick’em Jenny last erupted on December 4, 2001 – the time of the last orange alert issue – and it has erupted twelve times since 1939. No tsunami was generated.
Authorities in Barbados have reiterated that no tsunami watches or warnings have been issued, and continue to urge calm in light of the announcement. Similarly, in Grenada, authorities there have been advised that there was yet no need to move residents from coastal areas.
Authorities in the Eastern Caribbean and at the SRC will continue to monitor the readouts from the Kick’em Jenny monitoring instruments over the next 24 hours and will provide media updates as necessary. AMG will continue to monitor developments, and any changes to the current level of alert.
This is a rapidly developing story.
Replies
I hope Jenny decides to "kool" her self.
An active underwater volcano off Grenada's northern coast called Kick 'em Jenny was rumbling Thursday and regional disaster authorities were put on alert even as they said it posed no threat of triggering a destructive tsunami.
Since its discovery in the 1930s, Kick 'em Jenny has erupted beneath the surface of the Caribbean Sea at least 12 times, most recently in 2001. The underwater volcano, which rises some 1,300 meters (4,265 feet) above the seafloor on a steep slope of the Lesser Antilles ridge, hasn't caused any deaths or injuries.
The Seismic Research Center at the University of the West Indies said seismic activity had increased at the submerged volcano, which is just 8 kilometers (5 miles) north of Grenada. Recreational divers have reported seeing some "degassing" on the seafloor off Grenada's west coast as gas-rich magma bubbles.
Center researchers put the alert level at "orange," which means an eruption could take place within 24 hours. An eruption would stir up high waves and heat surrounding waters to boiling temperatures. Scientists say the volcano can also shoot hot rocks up through the water column.
Under the alert, all boats must stay at least 5 kilometers (3 miles) from the volcano. Kick 'em Jenny poses the greatest threat to mariners since the gases it releases can lower the density of the water so significantly vessels can lose buoyancy and sink.
Clevon Ash, an education officer at the Seismic Research Center, said the volcano's summit is roughly 200 meters (218 yards) beneath the surface, cancelling out any threat of a destructive tsunami.
"It is still too deep," Ash said.
People on Grenada were advised to go about their lives normally. But some were jittery.
"People are just wondering what's next," said Kendel Mark, a resident of the outlying island of Carriacou.
In a 1939 eruption, Kick 'em Jenny shot a cloud of ash 270 meters (900 feet) above the sea surface. Its eruptions since then, have been weaker.
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Associated Press writer Linda Straker reported this story in St. George's, Grenada, and David McFadden reported from Kingston, Jamaica.
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