Update by Robert Felix on OCTOBER 10, 2011
A submarine volcanic eruption is taking place approximately 3 miles (5 km) off the southern coast of El Hierro, the smallest of The Canary Islands, says this article on irishweatheronline.
Canary Islands – MODIS satellite image -7 Oct 11
This afternoon, Terra Noticias/Agencia EFE reported an eruption 2000 metres below sea level in the Las Calmas sea. Spanish newspaper El Mundo placed the depth at 1300 metres.
Initial reports of the eruption came from crews on four separate ships.
Scientists remain unclear if the emissions are gas or lava.
“The eruption takes place amidst an unprecedented earthquake swarm in El Hierro. The number of earthquakes recorded since July 17, 2011 on El Hierro has now exceeded 10,000.”
Hierro, a shield volcano, last erupted in 1793. The eruption, which produced lava flows, lasted approximately one month.
Although government authorities have suspended ferry activities to and from the 285 square-km island, and have recommended that boats should not sail closer than four miles off El Hierro, and have warned divers to suspend all activities, the estimated 11,000 residents of El Hierro were being reassured not to be alarmed.