El Hierro eruption

[Janet]

There have been around thirty more tremors this evening since my earlier post, most between 1.8 and 2.7 on the Richter scale. The above diagram shows the distribution. Experts say that this latest swarm is showing new magma intrusion between around 16 to 25 km. As they have said before, "something interesting is happening". JA

[Janet]

Yesterday's tally was 143 earthquakes. Today, already by 8am, there had been 24 registered (the registration ignores the minor tremors), the strongest of which was 3.1 on the Richter scale at a depth of between 16 and 18 km. These are occurring under land, though some are in the Golfo area under the sea, as the above graphic from yesterday shows. JA

[Janet]

As the experts have said before, the magma is looking for a way out, and is choosing new routes every time its path is frustrated. As such, one of the more interesting elements of these tremor swarms is the way the quakes "migrate": the pattern of movement shows very clearly the new path that the magma is tracing. Now it is clear that the current swarm is moving towards the unpopulated west spur of the island. This swarm of tremors, however, marking a new magma intrusion, seems to be slowing down. Perhaps this path too is blocked. Only time will tell where the magma will try next. One thing seems certain, though, and that is that we have not heard the last of this "eruption".

[Janet]

Experts say that this swarm is dying down now, with just 24 tremors yesterday. Their readings show magma at a depth of 16 to 18 km reaching other channels in a way to the surface. The island's deformation continues as expected, mainly in the east – the opposite side to that where the tremors are taking place: this appears to be because the tremors are releasing pressure, whereas in the east the pressure is building up. Looks like we will now have to wait for the next swarm to give a few more hints of developments. JA

[Janet]

 There was a spurt of activity last night culminating in a quake of 3.8 on the Richter scale, the strongest so far this year. It was on the western tip of the island at a depth of 18km, and was felt by the public. The deformation in the east also continues. Experts say that the idea that this swarm was dying away may have to be revised. In all, there were 117 tremors yesterday. There have been around 50 today, though that figure will be confirmed tomorrow: all have been around the western tip, with the most powerful registering 2.9 at a depth of 14 km.JA

[Janet]

 There were 93 earthquakes yesterday, but today saw 134 up to 7pm, the strongest activity since the start of this swarm. They are gradually getting shallower, into a depth of around 12-14 km, which suggests, experts say, that magma is reaching higher levels. Several have been over 3 on the Richter scale. JA

[Janet]

Yesterday's count ended up at 164, the busiest day so far in this swarm by some way. Overnight there were a further 62 tremors over 2 on the Richter scale, hundreds of smaller ones, now getting slightly deeper again back to the 16 -17km depth and moving slightly out to sea off the western tip of the island. The deformation is what is really spectacular, however, according to expert vulcanologists: the west of the island has been forced 2 cm upwards in the last 24 hours alone.

[Janet]

As of 10pm, there have been 148 earthquakes today, those over 3 on the Richter scale being felt by the public. Involcan is sending scientists to the island tomorrow to carry out measurements and oversee analysis systems.

[Janet]

Yesterday's total was 159 earthquakes over 2 on the Richter scale. Today, the biggest quake so far, of 4.1 at 2.41pm, again to the west and under the sea at a depth of 16 km. A further ten quakes over 3 on the Richter scale followed within the next hour, the largest of which was 3.7 at just past 3pm. Many quakes have now been registered today over Richter 3, a clutch of eighteen of them between 3 and 3.9 started the day off around 1am. Accompanying these is a strong upward deformation, which is said to be sufficient to cause some cracks to appear in buildings and infrastructure.

The PEVOLCA committee of insular and regional authorities and scientists is to meet tomorrow to discuss the current crisis. At present they are saying there is no risk to the public, but they will be investigating potential scenarios which might arise in the near future. Experts say that today represents the strongest volcanic activity since the whole eruption started in 2011. JA

[Janet]

There were 224 earthquakes yesterday, one of which as we know was 4.1 on the Richter scale, the strongest since the eruption first started. Pevolca met as planned today and have said that there is a strong chance of a 4.3+ earthquake, they think a 75% or so chance, but maintain there is no significant risk to the public, at least not sufficient to warrant extraordinary measures. Although today was slightly calmer, 170 quakes had been recorded by around 7pm, many being felt by the public for minutes at a time, and there were reports of windows vibrating and rockfalls. About an hour ago, at 10pm, however, some quite strong earthquakes were registered, and these are still ongoing as I post at just gone 11pm. The magnitudes have not yet been confirmed. From what information is actually available of this last series, it seems that these stronger quakes are moving southwards and towards the island. JA