It has been a few months now since the eruption at El Hierro in the Canary Islands was declared “over”. But volcano awakens again with 930+ earthquakes and 5 cm bulge in last 5 days.
JUNE 29 : EL HIERRO GROWS BY '5 CM' DUE TO FRESH MAGMA , 933 QUAKES IN 5
DAYS (SINCE JUNE 24)
Fears continue to grow that an eruption could take place in the near future, following another 60 tremors yesterday. The head of the island's Cabildo, Alpidio Armas, has courted controversy by expressing his hope that an eruption will occur on land instead of undersea because it 'would attract many tourists' to see the spectacle.
- Since 12:41 UTC, harmonic tremor and earthquakes started to pick-up again. Our readers checking our pages a number of times a day should check the depth and the location of the earthquakes after 12:41 UTC. The increased HT is a new magma flow who fills up new lava tubes, cracks etc. Once it is filled up it HT will decrease again.
- Since 12:40 UTC, a strong tremor signal and many stronger quakes have been recorded. A series of about 10 strong volcanic quakes (probably well >M2.5) occurred between about 13:00-13:10. Magma is moving again, but we have to wait to see the location of the quakes.
- 933 earthquakes since June 24
- 123 earthquake of Magnitude 2.7 or higher!
JUNE 28 - PRESS RELEASE CONFIRMS DEFORMATION OF ENTIRE EL HIERRO ISLAND DUE TO MAGMATIC ACTIVITY
"We have observed a deformation of the entire island. The center of the deformation originates in the present earthquakes area (see below)
The energy release and ground deformation show an acceleration of the active magmatic process on the island of El Hierro, according to information forwarded by the National Geographic Institute at the direction of the Civil Protection Plan for Volcanic risk (PEVOLCA)
The GPS network solution, measuring the surface strain on the island shows that there is a clear process of inflation, marking an apparent center of pressure in the area where the seismicity is located. The total cumulative displacement from 24 June to 24 hours yesterday, is about 3-4 cm in the horizontal components and 4-5 cm in the vertical component.
Since the beginning of the new magmatic process on June 24, there have been over 750 earthquakes. An earthquake with a Magnitude 4.0, occurred yesterday at 18:55 pm in the Las Calmas Sea, 2 km from the coast and 20 km deep.
Be remembered as the seismicity started in the El Golfo bay, then moved to the center of the island, coinciding with the point of intersection of the ridges, and later migrated to the west. Since the 25th of June the seismicity is concentrated in the west and El Julan. From 12:00 hours. On 27th of June, seismicity began to migrate towards the Las Calmas sea."
JUNE 28 - EL HIERRO VOLCANO FEARS CONFIRMED
Hundreds of tremors have been recorded on the island since the week-end, some of them measuring a worrying 4.0 on the Richter Scale. The population has been urged to take precautions, including keeping a suitcase packed should evacuation be ordered, in case the situation worsens. As last year, the volcanic activity comes as El Hierro is preparing for the summer tourism season.
JUNE 28 - VOLCANIC ACTIVITY LIFTS CANARY ISLAND
JUN 27, YELLOW ALERT RAISED AT EL HIERRO IN THE CANARY ISLANDS
INVOLCAN, the Volcanological Institute of the Canaries, along with PEVOLCA (the Civil Protection Plan for Volcanic Risk), has raised the alert status in parts of El Hierro to “Yellow” after increasing signs that we could be headed towards new eruptive activity in the Atlantic Island. The increased seismicity reported over the weekend was part of the rationale, however, new data suggests that the 2-3 centimeters of deformation have occurred over the last few days, all supporting the notion that magma is intruding under El Hierro. Remember, when magma intrudes the crust, it has to make room for itself, so deformation is one of the tell-tale signs of this intrusion (however, deformation can occur due to other processes as well, but combined with seismicity, magma is usually a good culprit). This new deformation is centered to the northwest of the submarine vent that opened last fall, putting it near the El Julan and La Dehesa areas on the coast. As for the seismicity, the island registered over 200 earthquakes on Tuesday alone.
JUNE 25 - SIGNS OF REVIVED ACTIVITY AT EL HIERRO IN THE CANARY ISLANDS
It has been a few months now since the eruption at El Hierro in the Canary Islands was declared “over”. There may be some passive degassing on the seafloor from the new vent that formed at depth to the south of the island, but things had settled down. Even the people of Restinga were putting the eruption in the past, with both webcams taken offline and the guarantee of €600,000 (~$750,000) from the government to aid fishermen whose livelihoods had been altered by the closed fisheries.
However, with any active volcano, it can be difficult to predict when exactly an eruptive cycle is truly done. Over the last few days, seismicity under the island has resumed and its manifestation is very similar to what we saw last summer during the lead up to the eruption of El Hierro in October 2011. Over 50 earthquakes have been recorded at El Hierro, some as large as ~M3.5 and AVCAN thinks that the new seismicity suggests that magma is moving in the same conduits as the fall 2011 activity. The earthquakes are, as of now, still deep – upwards of 15-25 km below the surface. This likely supports the idea that there is new magma entering the El Hierro system at depth. Now, last summer it took months of constant seismicity before we saw any surface manifestation (the submarine vent at ~88 meters depth), so we may not know if this new intrusion of magma will lead to new eruptions until the fall.
EQ Swarm data of Jun25 posted on PS Ning by Lonne de vries :
JUNE 24 - NEW SEISMIC SWARM AT EL HIERRO VOLCANO
At El Hierro, Canary Islands, Spain, a new earthquake swarm seems to have started late tonight. The strongest earthquake being a M 3.1
Also you can find info about previous activity (November 2011) of El Hierro volcano below: