Active Volcanoes / Aktive vulkaner: Hierro, Canary Islands

© http://www.canary-travel.com/El_Hierro/MapaEl_Hierro-in.html

The triangular island of Hierro is the SW-most and least studied of the Canary Islands. The massive Hierro shield
volcano is truncated by a large NW-facing escarpment formed as a result of gravitational collapse of El Golfo volcano
about 130,000 years ago. The steep-sided 1500-m-high scarp towers above a low lava platform bordering 12-km-wide
El Golfo Bay, and three other large submarine landslide deposits occur to the SW and SE. Three prominent rifts oriented
NW, NE, and south at 120 degree angles form prominent topographic ridges. The subaerial portion of the volcano
consists of flat-lying Quaternary basaltic and trachybasaltic lava flows and tuffs capped by numerous young cinder cones
and lava flows. Holocene cones and flows are found both on the outer flanks and in the El Golfo depression. Hierro
contains the greatest concentration of young vents in the Canary Islands. Uncertainty surrounds the report of an
historical eruption in 1793.
http://www.volcano.si.edu/world/volcano.cfm?vnum=1803-02-

http://es.wikipedia.org/wiki/El_Hierro

Friday, January 20th, 2012
The survey conducted last week by scientists at the Ramon Margalef research vessel belonging to the Spanish
Oceanographic Institute (IEO) , was able to confirm the establishment of the cone of the volcano outside La Restinga
to a depth of 130 meters.

Surveys performed were carried out during the 10th and 11th January, and have also shown a significant increase in
the volume , both the cone and deposits associated with the emission of material. This increase covers almost entirely
the western submarine canyon.

These deposits run from the mouth of the volcano to about 2,000 meters depth. The deposits are divided into two part
at 950m depth. For the upper, scientists have estimated that the total deposits reached 57 million cubic meters of aluvial
fan to a volume of 88 million cubic meters, which is a total of 145 million cubic meters of material deposited.

This model has been given by IEO, and it shows that there actually are two places from where
volcanic material are emitted. As for the new one, to the left of the original one, lots of lava-ballons have
been reported west of where they usually floats up, and are probably coming from this new opening.
A certain volcanic activity in this area have been reported lately.

Tuesday, January 10th, 2012

Involcan and Guardia Civil Helicopteres images taken on January 9th, 2012

Excerpts from DIARIOELHIERRO.ES, 01.09.2012. 16:50 pm :
Professor of Tokyo Institute of Technology and maximum scientific advisor of the Japanese government on underwater volcanic eruptions, Kenji Nogami, has flown in from Japan.

Kenji Nogami said that there are no major differences between submarine eruptive processes in Japan and produced at this time in El Hierro. There are clear indications that it is entering a phase posteruptive.

The Japanese expert recalled that the Japanese submarine eruptions have lasted from a few hours to 2 years and their
duration depends on the amount of magma available. The potential contribution of new magmatic material from deeper
magma pockets, makes other scientists to cast doubt on the duration of this underwater eruption south of La Restinga.

On questions about the risk for the population, Nogami said it at least until the new volcano has not reached about
20 feet deep or less., When entering the explosive phase in Japan, it has led columns of up to 400 meters of gases
and pyroclastic debris of up to 1 kilometer distance from the eruptive source.
So we still have to wait and see if this is an orninary and normal submarine-eruption......

See the similarities with Terceira submarine volcano 1999-2000. Click here.

Sunday, January 8th, 2012

Update 08/01/2012 – 09:49 UTC
- Very few burning gas during the night although it would have been a totally different view with a light sensitive webcam. In developing the screen-shots we saw a lot of different color intensities.

- We are anxious to watch the satellite or helicopter images later today as we see a very wide and concentrated stain
- The comments this morning are again talking about the steaming process. As can be seen on the colorful images from
Involcan below, we are still talking about long steaming/smoking lava blocks, not a strong steaming portion of the water.
We do not think that this will happen as we expect in the next phase to see strong vertical steam jets getting to the surface, very limited in the beginning and gradually increasing.

- Harmonic Tremor is back to the values from yesterday, after having decreased to the minimum after midnight.
- Many people are talking this morning about the many seagulls they are seeing above the active vent.
If you look at images from the first jacuzzi’s, you will see the same phenomenon. Why ? We truly do not know.
It mzay be bait they find there as it is being killed by the volcano, but nobody has reported this yet or they may lik
e the higher temperature of the water
From Earthquake-report.com

Saturday, January 7th, 2012

Steam seen most of the time, and every 15 minutes you can see gas burning. Burning lavastones have
been seen last days, and several material has arrived on the shore at La Restinga.
Photo: Joke Volta From Earthquake-report.com

The submarine volcano El Hierro continues throwing magmatic material to the surface of Mar de las Calmas.
On the coast were numerous fragments of lava , confirming the continuous activity of the volcano.
In the coming days members of the IGN, with the collaboration of Salvage, will try to collect some samples to be
analyzed for further study of this eruption, which now have shown three months of activity.

We are not going to speculate on what is going to happen next, but we follow the development regularly.

El Hierro helicopter images photographed on December 5 -
image copyright and courtesy Guardia Civil Helicopteres and Involcan

El Hierro helicopter images photographed on December 5 -
image copyright and courtesy Guardia Civil Helicopteres and Involcan

Many more pictures can be found at Earthquake-report.com, click on the link below:
https://picasaweb.google.com/110327184570944806725/ElHierroJanuary52012?authuser=0&feat=directlink#

Thursday, December 15th, 2011

Problem with the lights below now probably solved.....
The above ship made some kind of a special cruising in the waters south of La Restinga yesterday night......
"C-Whale" routing this morning (15/12)

The nightly burning boat – the final word of a volcanologist
Hmmm. I have carefully watched the videos of the strange lights recorded by the web cams on the evening of 14 December, and I am more than ever convinced that they are absolutely NOT related to volcanic activity, take a volcanologist’s word
for it. The way the lights are moving from about 02:30 min in the second (shorter) of the night videos is clearly indicative
of a ship. There’s no way in the physical word that incandescent rock will remain persistently incandescent when it’s in
the middle of water, any piece of incandescent rock would be chilled and lose its incandescence at least on the surface.
Boris Behncke from the INGV-Osservatorio Etneo, Catania
All info about this from earthquake-report.com

This morning at 08.50 UTC

Wednesday, December 14th, 2011

Julio del Castillo Vivero surprised us by uploading a short video recorded just before midnight
The video is showing after 11 seconds some object lighting up in the sea and a couple of seconds later
another one lighting up. Is it a boat ?? We don’t think so, especially the second object shows a light
which is extinguishing smoothly. And the glowing material make sense if we see the very powerful
burst just before midnight (graph below)

Here you can see the light out by the volcano just after it lightened up at 11 seconds after start of the video.

There are still some activity going on south of El Hierro. However, quakes have almost ceased, except
for one this morning at 04:02 UTC, but as usual to the NW, out in El Golfo.

More in depth story now at earthquake-report.com/

How comes lack of news from the authoratives here reminds me of Kolumbus, submarine volcano in Greece?

Tuesday, December 13th, 2011

Something is going on outside La Restinga. There have been no quakes last days, and everything look
more or less quiet - but....

You can still see the spot where it is boiling up, allthough sun is shining, and large waves has been
forecast for today. However, the next picture was taken this morning on the Web-camera by "Penny".

There is a lot of discussion on what is going on. You may see more at this web-site.
Source http://earthquake-report.com/2011/09/25/el-hierro-canary-islands-spain-volcanic-risk-alert-increased-to-yellow/

undated picture

Following reported by Europa Press, Madrid (12.12.2011. 20:06 pm)
The active crater of the three(?) existing submarine after the eruption off the island of El Hierro, is now
shallower than in the first eruption produced on 10 October.

This may explain the seismic signals of possible hydromagmatic explosions produced in the last 72 hours.
"The tremor has pulses of variable intensity every 5-10 minutes," says volcanologist.

New data from two oceanographic vessels, have agreed that "the eruption of lava blocks being brought up
to the surface from about 150 feet deep (about 50m ?), although not known which of the craters they come. "

In that sense, "the 200 meters below was the 28th of October, has now risen about 50 meters (?).
This explains the frequency of occurrence smoldering fragments floating in the Mar de las Calmas..

Although now 63 days to comply with continuous eruption, the island of El Hierro has gone from red to
yellow alert. "The red alert is only maintained in the marine area of the eruption.
To me, this just makes just more confusion to the ongoing eruption.

From earthquake-report.com comes the following understandable comment:

Some think the eruption would stop if the earthquakes are halted“.

Dr. Boris Behncke from the INGV-Osservatorio Etneo, Catania commented on this statement as follows :
As a matter of fact, most eruptions are preceded by earthquakes, but in most cases the earthquakes stop
once the eruption has reached a stable regime. The stopping of earthquakes does not mean that the eruption
will stop anytime soon, the eruption might continue for years after the end of significant earthquake activity.
Earthquakes are indicative of breaking rocks, caused by magma pushing into areas where there is no
established conduit.
Once a stable magma flow occurs through a well-established conduit, there will be no longer any earthquakes.
The cessation of earthquakes only means that the situation has somehow stabilized, not that magma is ceasing
to flow. The real indicator of continued magma flow is volcanic tremor.
Only once the volcanic tremor disappears, then one might reasonably argue that the eruption is over.

Sunday, December 11th, 2011
Instituto Geográfico Nacional (IGN) reported that during 30 November-6 December the submarine eruption
continued S of El Hierro Island, with lava balloons sporadically observed floating on the sea.
During this period, the mean tremor amplitude was similar to the previous week. Twenty-eight seismic events
were located, most of them offshore to the N of the island at depths of 15-24 km and with a maximum magnitude
of 2.8. Only one of these events was felt by residents at a maximum intensity value of II using EMS-98 (European
Macroseismic Scale). GPS data analyses showed stability in the horizontal components; the vertical component at
stations located on the S and NE parts of the island showed subsidence.

Tuesday, November 22nd, 2011

During the weekend there have been fewer quakes, but then some of them as strong as 3.7 and 3.3.
Scientists suggest these were a result of rocks falling down inside the volcano (?), or that more
magma was trying to get up. However, it all happens deep down between 17 and 25 km below surface.

Friday, November 18th, 2011

Latest: 15.32 UTC new quake magnitude 3.7

Since the quake of magnitude 3.6 (three point six) yesterday, there have been 42 other quakes,
of which the strongest have been at 09:47 this morning of magnitude 2.9, and another,
also 2.9 at 11:55 at noon today.

What puzzles me is that two of the local news papers on the Canary Islands both could tell this morning
that yesterday showed 18 quakes, no stronger than 2.6 (two point six), and that the the activity was reduced.

So far, to day, at 14:00 local time, 32 quakes have occured, two of 2.9 on Richter scale.

Thursday, November 17th, 2011

Picture taken yesterday, Wednesday's helicopter Civil Lair. Courtesy Guardia Civil / non-tip

A quiet day, untill 16:25 UTC when a quake of magnitude 3.6 took place - as usual to northwest of Frontera.

Scientists now agree that if there will be no more strong quakes after the one last week of 4.6.
it should be possible to say that the volcano has calmed down 20 days later.

Scientists at the Oceanographic Vessel 'Ramon Margalef', the distance between the sea surface and the crater
of the volcanic cone is maintained at about 180 meters, "which rules out any explosive process at risk for people. "

Tuesday, November 15th, 2011

Still only few quakes, up to a magnitude of 3,1 on Richter scale.

Still the volcano keeps quiet, although there has been reports of steam coming up to the surface off La Restinga.
However, again we read in newspapers from far away that the residents of La Restinga were allowed
to go back home, after having been evacuated for a long time. But nothing about this in local newspapers (?).

El Hierro residents estimated that the crisis had cost them around 4 million euros in lost earnings from the
island's hotels, restaurants and diving schools, although business had picked up in recent days with increasing
numbers of people traveling in order to look at the volcano, as its underwater eruption was visible from the shore.

High temperatures were reflected from the surface manifestation (bubble zone) of the submarine eruption of El Hierro. Higher temperatures reflected in sea surface were recorded on 6, 7 and 8 November, reaching values ??of 30.9 ° C, 24.8 º C and 29.7 ° C.

Monday, November 14th, 2011

It has been a relatively quiet weekend, with few quakes, up to a magnitude of 3,1 on Richter scale.
This has been the way the 'volcano' has behaved so far - after a strong quake - a quiet periode - and then
again a strong quake. So what now?

Friday, November 11th, 2011

Now a web-cameras have been put up. Click here.
One camera points out toward the sea, where the bubbles have been seen,
the other with a view of the village, La Restinga.

However, a panel of scientists now predict the possibility of an eruption north west
of the island also, so we will have to wait for two more cameras,
or for more news to come.

Noon:

Source: IGN
Tablle shows from July up till now, accumulated energy down where the quakes originate, some 15-22 km
below sealevel, and at present NW of El Hierro - see map below.
Note the jump up that followed the strong quake yesterday night.
Something down there is really trying to come up. But the big question now is WHERE?

Source: IGN
Quakes for the past three days, all NW of the island, in El Golfo.

This morning:
Minutes after midnight there was an earthquake of magnitude 4.6, which was felt by the population,
even as far away as on the island of Tenerife.

Shortly afterwards there was another of 2.8 that could also be felt by the population. Later, at 5.30 of 3.1 degrees.
The earthquake of 4.6 degrees is the strongest of those in El Hierro since the eruption began.

As reported by the regional radio Pevolca, there have been landslides on a road in Frontera.

Wednesday, November 9th, 2011

Noon
Volcanoes are not easy to forecast, and that goes for this one also.
At noon it is reported that everything out in the ocean is quiet.
The sea is completely calm and the day is spectacular, with bright sunshine.
What's next?

Morning
04:15 UTC today a quake 3.0 on Richter
22:58 last night 3.7
17:51 yesterday 3.4
all NW of Frontera.
Bubbling activity in the sea south of the island has increased, and sent material 25 m up into the air.
Number of quakes yesterday was 62 and Monday 64.
Accumullated energy below where the magma flows, is still increasing.

The following from the german magazine Spiegel, makes us wonder.......

So far, the volcano has only shown its explosive power beneath the water. The lava is piling up on an
underwater mountain. That the eruption is capable of firing jets of water into the air shows that this
mountain is growing -- the center of the eruption is approaching the surface.

Geologists believe that new land could soon emerge from the sea, and islanders are already looking
for a name for the new territory. There are only 70 meters to go until the mountain reaches the surface,
experts from Spain's National Geographic Institute (IGN) have reported.

The quakes are showing a pattern typical of flowing magma, the so-called harmonic volcanic tremor --
a clear sign of impending eruptions.

And scientists have been warning since September that if and when those eruptions do occur,
they could well happen on land. In recent days, the tremors have shifted from the south to the north
of El Hierro. But it has now started moving upwards -- the most recent earthquakes have been shallower.

There could soon be eruptions in or near the El Golfo valley on the northern coast, the IGN has warned.
And an outpouring of lava could prove dangerous not only if it happens on land, but also in shallow water,
where it could result in large steam explosions,

An initial analysis of the material produced by the volcano so far has surprised experts: It provided
"clear evidence of the explosive potential" of the volcano.

Most so-called hot spot volcanoes, like those in the Canaries, produce basaltic magma with a relatively
small proportion of silicon dioxide (SiO2). SiO2 acts like a glue, producing very viscous magma,
leading to a buildup of gases which results in an explosive mixture. El Hierro volcano, however,
is feeding off two supplies of lava; a less volatile basalt magma and a much more explosive,
SiO2-rich magma.
http://www.spiegel.de/international/europe/0,1518,796612,00.html

Tuesday, November 8th, 2011

The volcano of La Restinga has reawakened. Since early this morning there came strong boiling with rise and fall
of intensity every fifteen minutes or so. This event is visible from shore.l This activity follows an earthquake
at 04:58 at 2.8 on Richter scale. Another one at 09:06 at 2.8 and then at 11:07 3.5 on Richter.

Most of the recorded earthquakes occurred mainly northwest of Frontera, between 10 and 24 kilometers deep.

As the bubbling restarted again made this fact prompt many locals to think of the possibility that the volcano may
be more virulent the 11th, with a full moon phase.

Sunday, November 6th, 2011


The town La Restinga on the coast at left. Right: When quakes occur in El Golfo, Northwest of the Island,
gasses and some magma comes up south off La Restinga.
from Canarias7

Last quakes listed as per Sunday at 19:35 UTC
Sunday 18:25   3.9 on Richter Scale
16:30    3.4
09:50    3.9
Saturday 09:44    3.9
09:05    3.5
08:59   3.0
00:50  3.6
Friday 20:36    4.4
13;41    3.8

Number of quakes last days:
Thursday 37
Friday 37
Saturday 27
Sunday /(till 19:35utc) 42

Evacues from La Restinga is allowed to visit their homes for maximum 1 hour a day,
and is transported by military busses.
Meanwhile everybody is awaiting to see what happens next.

Thursday, November 3rd, 2011

So far today, at 08:00 UTC (GMT) there are no more to report,
except to tell that the 4.4 quake yesterday, was the strongest so far since it all began in July.
To day military personell are setting up a camp for possible refugees, to take care of up to 1.200 persons.
The quakes are still so deep (25 km under surface) that scientists do not believe magma will come up yet.
See comments on Hudson volcano, where same happened a week ago.

Wednesday,November 2nd, 2011

As above picture shows, the accumulated energy under the 'new volcano' on El Hierro,
is again intensifying. The list shows the development since July 15th, with the upcoming of lava
and gasses around Oct. 5-10. Then a quiet periode until now recently.

Oct 24th 45 quakes, max 2.9 on Richter scale.
Oct 25th, similar but 2.7
Oct 26th, 45 quakes, max 3.1
Oct. 27th, 55 quakes, max 3.0
Oct. 28th, 63 quakes, max 3.3
Oct 29th, 62 quakes again, and max 3.6
Oct 30th, 93 quakes, max 3.9
Oct. 31st, 154 quakes, max 3.9
Nov.1st, 69 quakes, 3.9
Nov.2nd, 100 quakes, max 4.3 (at 07:55)

LATEST: 18.10 utc (gmt) 4.4 on Richter just outside Frontera in El Golfo

All quakes lately have occured in El Golfo, not south as recently.
The above picture shows quakes for the last three days.

Today an increase in CO2 is reported. Smoke has been seen south of La Restinga.
Authorities have updated plans for evacuation and follow the development closely.

We are again following the volcano on El Hierro closely.

Saturday, October 15th, 2011

Magma is still moving beneath the sea, but noone knows what will come. Pressure has been released
since gas has been coming up through the two new wents. But uncertainity to if any lava has come up yet.
Whole area in the sea is covered with a green mass which has to be analyzed.

Thursday, October 13th, 2011

From http://www.ign.es

Scitentists have now stated that there are two active wents, 3-5 kilometers off the coast of La Restinga,
from where lava is coming up into the sea. They hope to send down a submarine robot with cameras
to find out just what is going on.

The intensity and strength of last days quakes have been reduces, as shown on the picture above,
which show all quakes since July - with the highest number, 454, in one day around August 20th.
Since October 10th the activity has been very low.Since the end of September, the quakes have been
colored in red, indicating a magnitude of more than 2 on Richter Scale.
.
Tuesday, October 11th, 2011

17:00 UTC: About 60 inhabitants have been transferred to Valverde to a student house. Another 400 people
are now living with frineds or families elsewhere on the island. All maritim traffic is prohibited within 4 seamiles
off La Restinga. At present there are only journalists and rescuepersonell in the area.

16:00 UTC: Geologists are expecting stronger quakes between 4 and 5 on Richter scale, as magma is moving upward.
Since yesterday epi-centers have moved inland, and are now centered on top of the mountain ridge in the south.
Alertlevel has been raised from YELLOW to RED, and ferries to and from the island have been stopped.

List of latest quakes. Note that the newest onex all have been centered from the mountain ridge and southward.
From http://www.ign.es/ign/resources/volcanologia/html/eventosHierro.html

About 700 inhabitants in the town of La Restinga have this afternoon been informed in a footballfield
outside the town, and are preparing for an immidiate evacuation in case of an eruption on land.
It is expected that many of them have to spend the night outside their homes, preferably in the footballfield.

At 15:45:37 UTC there was a quake SW of El Pinar, 2.7 on Richter scale.
15:21:21 same place at 2.3
and at 14:39:19 SW of Frontera, 2,0 on Richter.
------
Around 10 o'clock last night it was officially confirmed that the earth had opened up five kilometers south of
La Restinga and was a result of the earthquake incident on Saturday evenening at 21.37 (see Sunday below).
. Data provided by the IGN gave "evidence of a submarine eruption" at 600 meters deep.
The alert remains yellow and the authorities ask the public to show tranquility.

When flying over by helicopter a significant amount of dead fish were seen at sea.
Authorities now also believe that the explosion was greater that first anticipated, and that a large amount of lava and gasses have come up. A single source reports of an eruption at 1.200 m deep at 10:43 AM yesterday, Monday, in the sea of Las Calmas.

.It has now been expected that the pressure decreases, and so the seismic activity. It is therefore also expected that
the authorities today will reopen the Roquille tunnel, which has been closed for more than 15 days.
People who have been evacuated will also be allowed to return to their homes.

Sunday, October 9th, 2011

An earthquake of 4.3 magnitude on the Richter scale was recorded last night in El Hierro, a magnitude "expected"
owing to the magma infusion phenomenon that has occurred on the island since last July. The incidentt occurred
at 21:37 pm yesterday, is the largest size of 9600 earthquakes recorded in recent months
and was felt throughout the island, although there were no major incidents except for some landslides.

Scientists tell that there may happen movements with magnitudes between 4 and 4.5 degrees on the Richter scale,
or even somewhat higher, but to produce a volcanic eruption there have to be other elements and not only the
magnitude of earthquakes. The scientist also said it has to produce an acceleration of ground deformation and
migration of magma towards the surface.

http://www.ign.es/

Regarding the location of the epicenter, it was a mile from the coast of La Restinga.
This little fishing village is situated at the south eastern tip of El Hierro, the southern-most point of the Canary Islands.

Tuesday, October 4th, 2011
So far to day there have been some quakes off the coast, about 20 km out in El Golfo.
Size of the quakes have been between 2.0 and 3.6 on Richter scale.

Roquille tunnel has been closed a few days and such forces inhabitants in Frontera to go over the
mountains to get to Valverde. Also schools in the area are reported to have closed and left
some hundred pupils at home. This all because of risk for stronger quakes in the area.

Sunday, October 2nd, 2011
About midnight Friday to Saturday, 17 quakes occured, of which 6 were between 3.2 and 3.6 on Richter scale.
The magma is still trying to reach the surface, but is still probably 20 to 25 km under the surface.
The last few days the quakes have been situated off the coast, and not any longer near Julan, to where it moved
earlier after having started at sea. If the magma can not reach the surface out in the sea (may we see a new Island,
as Surtsey?), then it may return toward the coast again.