As the smoke starts to clear at El Hierro we get a much more detailed picture of what is happening. As data has poured in we can now deduce a few things.
First of all GPS figures today confirmed that this is indeed a fourth bolus of magma coming up from the depth. The first one in July 2011 started the entire hubbub and in the end caused the sub-aquatic eruption south of La Restinga. A second bolus in January that followed the same path revigorated the ongoing eruption briefly, but was too small to keep up the pressure in the volcanic system and the eruption dwindled to a halt. The third bolus is so far the most interesting, during a few days more magma arrived than during the first one that caused the eruption. The magma arrived at the same place as for the first two (around the Tanganasoga volcano), but then it took an entirely new path and created quite a few earthquakes as it moved towards the western point of the Island. The fourth bolus also arrived at Tanganasoga, and immediately started to move south and slightly downwards.
We still have only one set of data points for the GPS, but since it is visible on many of them it is still credible. What is a good test for if there is actual inflation or not is to check for motion in EW and NS directions. A false read normally does not show that.
The earthquake swarm is very vigorous with more then 100 earthquakes per day. The pattern is still continuing with a south and slightly down dipping motion. We will see if the hard tested village of La Restinga will have to suffer both the knowledge and the feeling of magma moving straight down under their feets.
We can also rule out any degassing or actual small eruption, what initially looked like harmonic tremor are most likely small earthquakes, there is no clear signal showing harmonic tremor to this date.
There is no way to know if this bolus will cause an eruption or not. The lack of harmonic tremor says that it will at least not happen within the next 24 hours or so. But, for the residents on El Hierro the same advice is always valid, stay on top of the news.
604 thoughts on “A brief update on El Hierro”
All quiet at Hierro? No I don’t think so. The HT is higher on the other sites. CHIE is extremely downscaled. I think the authorities asume that we are stupid
No, I do not think they think people are stupid. It is kept scaled back due to their concern an eruption will start soon. And if it starts and is upscaled it will only clip. The others are kept on high for locationing, but CHIE as the main unit is scaled back in preparation.
There is no HT visible on the others, except for a low frequency hum associated with deep magma movement.
Few quakes, no extended uplift, I would say the fun is over for now. It could though change at any time.
Comment deleted in violation of rule 6.
“Any intervention by a Moderator/Dragon is to be discussed over email with the list-owner.”
Second warning for this now. In total 3 warnings. Do you see where this is heading?
Thread very very lightly from now on.
Welcome back Henrik! Nice new hat!
Covers the lobotomy scars admirably, I must say.
See Rule 6.
Since I started with ot… It’s dark, windy and raining, with occasional lightning, I think i’ll take a walk with the dogs since the weather is so nice 😀
It seems that the village I live in is preparing for zombies, the only place vehere streetlights are on, is the graveyard 😈
Maybe they know something you don’t ……. 🙂
shiver.. shiver…. where do you live, Stoneyard?
Southern Finland, Near Porvoo, and it’ts warm, 12 degrees
Oh that is far away, good to hear. 🙂
Warm? 12 degrees? Brrrr. That is just a little (5 degrees) warmer than the fridge.
This is just nice Icelandic summer temperatures! 🙂
But Iceland has the Blue Lagoon, so you can always have a nice, warm bath there!
*envy written on my forehead*
Grusel ,grusel … 😆
This should have been an answer to Stoneyard 18:09, but the ghosts transferred it. 😡
I am going to edit in a rather massive post now.
A new short post is up!