El Hierro Volcano (Canary Islands) : Red alert – an impressive new stain forms in front of the coast

Last update: November 5, 2011 at 1:58 pm by By Armand Vervaeck and James Daniell

Data update 05/11 – 13:04 UTC :
Harmonic tremor remains very strong, while there were some slightly weaker periods during the night (see graph below).
– we have no data update from the Las Calmas sea at the moment. Only the picture below, which reveals a growing grey stain. The grey stain is believed to contain a lot of eruptive material.
– The webcam soap goes on, it takes 25 siestas before somebody @ El Pinar decides to do something (Joke is running the marathon to get something done).
Focal depths are still at a safe 17 to 21 km. But … what is safe, if a fissure eruption is going on only at a depth of 150 meter or less (as Raymond says) in front of the southern coast.

The eruptive grey and greenish stain during Saturday morning (right bottom corner, one of the oceanographic ships) – image copyright and courtesy Delmi Alvarez and Carias7.es

Update 05/11 – 12:13 UTC :
Our friends at IGN have a hard time too, as their servers are almost strangled by the many people visiting their lists and graphs. We have to thank IGN for their outstanding open source information. Specialist followers always want more, but we never had the feeling that information was kept away or hided from us.
The same goes to the government of the Canary Islands, the local administration and the UME, IGN, CSIC and other people guarding the safety of the islanders. They have an extremely hard time in communicating a very complicated information without a 100% guarantee (please bear in mind we talk about a volcano)

Update 05/11 – 12:13 UTC :
The coastal village / town of La Restinga is almost strangled by the current events. The village, mainly dependent on small fisherman and diving companies, is going through his hardest time since his existence. As all trade did came to a standstill since the early evacuation days, people have hardly something to eat! Aid has been promised, but the political and administrative hassle takes too long.

Update 05/11 – 11:28 UTC :
Pevolca will meet this morning at 12:00 UTC to discuss the present situation. We expect that Pevolca is re-considering the (partly) closure of the Los Roquillas tunnel due to the frequent and strong earthquakes. The landslides and rockfall yesterday evening at Las Puntas (greater Frontera area) and the mandatory evacuation of 11 houses are indications in that direction.

Update 05/11 – 11:15 UTC :
3 rather strong earthquake respectively 3.0, 3.5 and 3.9 have struck the El Golfo area to the North West of Frontera. The focal depths were in between 20 and 21 km (as most of the others before).
The big difference with prior periods is that we now are having AND continuing strong earthquakes AND also INCREASED STRONG harmonic tremor. The rescaled IGN graph (yesterday evening) is almost saturated again.All this means very strong volcanic action below El Hierro.

Harmonic tremor from midnight UTC (05/11) until 11:00 UTC – image courtesy IGN

Update 05/11 – 08:44 UTC :
After last nights powerful 4.4 earthquake and even more after the shallower 3.6 earthquake with epicenter in the Puerto Naos area (south of the Island and almost below the Jacuzzis), the population of El Hierro is struggling in between the “Remain Calm” message of Pevolca and what they feel and see and smell themselves.

Los Roquillos tunnel closed until the early morning hours
The Director of the Civil Protection Plan for Volcanic Risk (PEVOLCA) has decided this evening to close thetunnel access road until 7.30 am as a preventive measure due to the 4.4 earthquake which took place at 20:36 hours. The possibility that a larger quake could occur according to the National Geographic Institute (IGN) required the notification to the public. The opening of the tunnel in the morning will be done with surveillance and security measures in place.
– The families living in 11 houses in Las Puntas have been evacuated out of fear of damaging landslides

Update 05/11 – 00:37 UTC :
New 3.6 magnitude earthquake occurred at 00:16 UTC in the Puerto Naos area. The depth : 11 km. The quake was felt by islanders.

Data Update 04/11 – 18:53 UTC :

– Very strong harmonic tremor continues to feed the current eruptive vents
– The harmonic graph below is saturated from 13:00 UTC on = strong eruptive period
– 1 strong 3.8 magnitude earthquake at 13:41 UTC – location : El Golfo bay (approx. 4 km out of the coast – depth : 21 km
– 26 earthquakes since midnight UTC (less because of the eruptive period) – 2 earthquakes in between 1.5 and 2, 8 in between 2 and 2.5
– 2 earthquakes were felt by the islanders