Shortly after moving to the Costa Blanca, we discovered that in the nineteenth an earthquake had destroyed a small town close to the urbanisation where we had made our home. Nowadays, we live on a volcanic island in an archipelago where there are still several active volcanoes.
One of the very first pieces of advice that we received when we arrived in the Costa Blanca, and one that we quickly learned to be particularly valuable, was “Never believe what you hear from bar gossip; always find out the facts for yourselves.” Bar chat is easy and, like Chinese Whispers, often varies significantly from the truth, and particularly if it is bad or disturbing news. However, many expats, desperate for information and advice in their own language, often readily fall for misleading information.
The current topic in many of the British bars in the Canary Islands is the issue of seismic shocks currently underway in one of our neighbouring islands, El Hierro. This island paradise is quickly becoming the source of overreaction and potentially dangerous gossip causing concern. So what exactly are the issues?
Over the last few weeks, seismic shocks on El Hierro, which the experts call ‘swarms’ have been mostly of low magnitude since they started in early July, and most of the seismic activity has been limited to about 9 to 16 kilometres below the surface. The question on everyone's mind is, “Is El Hierro heading for an eruption and, if not, what is going on beneath the surface?”
We need to remember that the Canary Islands are volcanic in origin and a wide variety of lava has erupted from Canary Island volcanoes over the years. This is what makes the islands what they are, and without the volcanic eruptions in the past there would be no Canary Islands. Experts tell us that they are similar to the volcanoes found in Hawaii, and that they share many similarities in that they can grow very large and that the style of eruption and lava flow are similar.
Should we be surprised by this seismic activity at El Hierro? The answer seems to be: No. Although the islands’ volcanoes are nowhere near as productive as Hawaii or indeed Iceland, the Canary hotspot is one of the more vigorous on the planet. Does this seismic activity automatically lead to an eruption? Not necessarily, and this activity might not even lead to an eruption. However, now that we have many of these volcanic systems so closely monitored, we notice this subtle activity as it happens, rather than waiting until we can feel the seismic activity on the surface, which usually means that an eruption is highly likely. In other words, there are plenty of warning systems and the monitoring of seismic activity is constantly taking place.
These incidents should remind us that El Hierro is an active volcano and that these signals might be a warning of an eruption sometime in the future. However, it could be many years between a seismic swarm that eventually leads to an eruption of the volcano.
It is always a good idea to be prepared, especially when living on a volcanic island. Over 10,000 people live on El Hierro, and emergency planning will tell residents what to do and where to go if El Hierro does decide to erupt. However, most eruptions produce lava flows and ash that are not likely to be a major threat to the island’s residents unless they are caught unaware, which is highly unlikely. People on Hawaii have been living with a constantly erupting volcano for over 30 years, Mount Etna in Sicily performs a regular firework display, as do the volcanoes in Iceland; so any activity on El Hierro should be impressive to watch, but not a catastrophe for the residents of the island, nor indeed for the rest of the Canary Islands. So back to your gin and tonics and the sun beds; you now have the facts and not just the bar gossip. Cheers!
© Barrie Mahoney
From the 'Letters from the Atlantic' series by Barrie Mahoney
Living in Spain and the Canary Islands : ISBN 978-0995602724