El Hierro Update

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El Hierro Volcano : Green and Yellow alert – today : RECORD number of strong earthquakes (88) since September 30, 2011 (pre-eruption phase)

Last update: June 25, 2012 at 3:58 pm by By

Update 25/06 – 15:45 UTC
-The number of earthquakes is picking up again
– Today will have the highest number of (M+2) earthquakes since September 30, 2011 (pre-eruption process at El Hierro). IGN has still a delay of several hours and we have counted already 88 M+2 earthquakes.
We have compared data from the full length of the eruption process. On November 3 (fierce action) 62 M+2 earthquakes were registered.  On October 6, 2011, 88 M+2 were registered.

Update 25/06 – 15:28 UTC
– As stipulated in the 14:36 UTC update, we see a drastic decrease  in number and strength of the earthquakes. It looks like the strongest swarm episode  is over for now and we expect no further deterioration of the situation if the current activity continues.
– Earthquake Animation of Julio del Castillo Vivero in cooperation with Avcan – magma trail has been currently blocked at El Julan (last set of bullets)

Update 25/06 – 14:36 UTC
– We have the impression that, based on the HT hourly graphics, HT and the number of earthquakes has decreased considerably although we still notice strong ones.  Probable explanation : Flow decreased due to blocked lava tubes, but pressurizes the paths even more which is related to a number of stronger quakes
– 82 earthquakes (the most important ones) listed by IGN until 12:12 UTC (we are now more than 2 hours later)
– The AVCAN map below shows the “road” the magma is following while pressurizing the below the island tunnels. The magma is gradually moving from the El Golfo island towards a cluster below the old volcano crater and finally towards El Julan (south coast). It still has to travel a little bit towards the submarine crater to restart the eruption process. The main question now is whether it will reach and reopen the cone or withdraw before that.

Map (without green line) courtesy AVCAN – quake locations based on official IGN list

The El Julan coast where the magma seems to have been blocked (last recorded group of listed earthquakes) – image Joke Volta

for more information and updates, go to:   http://earthquake-report.com/2011/09/25/el-hierro-canary-islands-spain-volcanic-risk-alert-increased-to-yellow/