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Fataga ( Gran Canaria)
San Cristóbal de La Laguna in 1880 (Tenerife)
Caldera de Taburiente National Park (La Palma).
Garajonay (La Gomera)
(BBC/ 20111204)Canary Island volcano: A new island in the making?
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BLOG/ Startseite JANUARY 28- FEBRUARY 02- 2014
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click here for previous page / January 20- 27- 2014Ich habe beschlossen den Blog, bzw. zumindest die aktuellen Berichte in englischer Sprache fortzuführen. Mit Englisch lässt sich das alles einfacher kürzer und genauer ausdrücken. Deutsch ist besser zu verwenden für Dichtkunst oder um Geschichten zu erzählen,. Außerdem kann der Blog dann von mehr Menschen gelesen werden. Natürlich können Kommentare weiter in deutsch oder anderen Sprachen verfasst werden This blog does not intend to give scientific advice or analysis. Its just wants to document the ongoing volcanic activity and the real events how they envolve, what might serve also as a basic for own conclusions. Recently I decided to continue this blog - at least the activity updates and report- generally in English language. My English might not be perfect, but at least better than an automatic translator.Its easier to express anything in English than in German and it makes the blog easier understandable for international users. Special stories might be written in German. Comments can be posted in all languages, I recommend to use English, so comments are understandable for the most international visitors ---- -----------------------------------------------Sunday- February 02- 2014:update/ 10:20 UTC Another one- same place, same depth like the one before early this morning. Just a bit stronger:
Another microquake from the mantle plume below El Hierro: This time from 11 km depth as " usual". This- due to all experts - means,: new Magma is rising up in the mantle plume from the depth of the hot spot below El Hierro and likely flows into the suggested large magma chamber or caldera in some 8- 10 km depth anywhere below the islands. No further quake from lower depth yet, that would indicate, magma comes up also towards the surface.
The epicenter was this time off the Eastern coast- about 5 km Southeast of near El Pinar:DEFORMATION:No deformation data yet for February 2014 TREMOR SIGNALS: On the IGN website , only the values of CTIG / SHZ station are published. Another seismographic plot for El Hierro (La Fontera/ CTAB station ) can be found on volcano_discovery.com However: all El Hierro shows today increased harmonic tremor, indicating (new) magma flows in the depth: (the image was updated at17 UTC, as activity increased during the day): Due to the seimograph at IGN, tremors on all island began to decrease at the same time, when these new quakes began ( what makes the riddle even bigger) : On February 01, they were relatively strongest on Gran Canaria:^ the seismograph was turned off yesterday after 17:30, the one on La Gomera after 22 UTC : Both seismographs were still turned off at the time of this update on on February 02 at 5 UTC Seismographs on Tenerife were yesterday first time online since more than one week and also show suddenly only weak harmonic tremors: the graph, the IGN website displays for today- Februray 2nd, is again the disturbing graph of January 15/ 16 ---------------------------------------------------------------------Saturday- February 01- 2014:2. update( 15:55 UTC) uppps. That doesn`t look good! " El Discreto" ( or the "monster in the Depth") has yet made another hic hoc today. Stronger and in just 3 km depth!!
THe Epicenter was again on the South Western side of the island in the "Valle del Golfo": I will next week publish an article about how solar proton storms (SEPs) heat up the Earth mantle what causes intensive hot spot activities, as also each of the three activity phases at the El Hierro hotspot ( in 2011, 2013 and now since Dec 2013) followed solar Protons storms. DOES THE MAGMA NOW COME UP TO THE SURFACE ANYWHERE IN OR IN BETWEEN THE ISLANDS We have just to follow they simple logic of the experts to say: POSSIBLY YES! OR RATHER LIKELY? So lets wait and see: If reayll now magma has begun finally to rise up to the surface, it will certainly have to "bomb" its way free to more of the elder volcanic channels and structures in the formation with some more explosions . These explosions would be measurable as earthquake then and can be located from which depth they come and form which location before any eruption would occure anywhere and maybe even just on the ocean floor . So its a bit too early to state this. I will observe, what happens next and check out, what statement I can find follow by AVCAN facebook site But for the moment I just want to say. This is now the first quake since the first eruption in 2011, that happened in a depth of less than 10 km . Its even just 3 km deep However, all experts concluded , that these microquakes stand for magma intrusion into an old caldera/ resp magma chamber deep sugessted to exist anywhere below the islands in a depth of appr. 8- 16 km. During the phases in March 2013 and now ( which is in real the strongest yet including the first new activity in 2011) this imaginary magma chamber- so the most experts concluded- must by an by have filled up with magma that would inavertibly erupt to the surface at any time if the boost from the Earth mantle ( where the hot spot activity has it origin) does not stop. WHAT IS WITH THE "MAGMA CHANNELS" INTO AFRICA" there is good evidence for a theory saying , that the canaries were once connected with the African mainland, from where they formally broke off at any time. Related to this theory large volcanic structures can be found on the African Atlantic coast in are area that begin some more than 100 km South of Agadir / Marroc. Unfortunately , was not at its formost southern point at the time when I saw this place on a journey through Maroc back in the 90th and I have unfortunately no pictures from that place. But maybe I find some in the www. The coastline there trurns into the form of a wider Bay with costal rocks out of huge layers of mainly black vulcanic basalt, witnesses of huge eruptions, But there is not any volcano in at least 500 km distance! The size of these formations with layers at least 1/2 to 1 meters thick is comparable to the volcanic layers that can be seen in the Eifel volcano field. What makes that place so strange is, that this costal formations end abruptly towards the sea are and are just remnants , the the edge of large structures that once broke of and dissapeared anywhere. More about the known history of the Canary islands in my next wee s blog! Some out of any reason , experts even suggested that there might be "magma channels " from the El Hierro hot spot below El Hierro to the next African volcano group in the South of Algeria more than 1.500 km to the West . And I myself could even image there might be a complete under world below our feet in a depth of more than 10 km we just can`t explore by any means! ( the deepest hole ever yet was drilled by BP in 2009 in the Gulf of Mexico wuith a total depth of about 13.000 meter below sealevel) : More about that in my next weeks blog! WHY SHOULD THE MAGMA BELOW EL HIERRO TAKE THE LONG WAY TO AFRICA? But why - I am just asking me -should take the magma from the hot spot below El Herro take such a long way through any old and most likely partially collapsed "magma channels" and erupt then anywhere in more than 4000 meter height in the Atlas mountainsof Algeria? . Its just like with all fluids: They take the easiest way they find, they way with the less RESISTANCE! Enough for today, Lets see what comes up next! Have a good time! 1. update ( 8:30 UTC) One never should say never- expecially if it is the " secret hidden Volcano "El discreto, that was quite now for more than one week_ IGN reports a minor quake from the very deep of 32 kilometers below the island that measured M 1.8 on the surface. The epicenter was again offshore near La Fontera in "El valle del Golfo" on El Hierro. Possibly a new boost of magma right from the Earth mantle?
--------- ------------------------ Friday- January 31- 2014NEWS FROM THE RESEARCH ON THE VOLCANO ACTIVITY:In the year 1999, after Spain had joined the EU, first time a research vessel made an scientific examination of the Canary islands. Bathimetric maps were generated . The examination of the seefloor around the Canaries allowed a new insight into the Canaries topography and turbulent geological history.marked by large landslides those must have occured anytime or repeatedly in historical times. These landslides have scattered their remnants on the seafloor such as nearby the islands of El Hierro and Tenerife. A huge piece of rock "missing" from the upper crater edge on the northwestern flanc of Mount Teide - that once slipped into the sea- however was found in such a distance to the island, that scientists just said, they don t know àny natural force , that might have done that . The mystery is still unsolved. Among the objects of interest was also a submarine volcano between Tenerife and Gran Canaria . The location is frequently , resp geologically active with quake activity. Some experts obvioulsy believe now, that the two micro quakes on January 26 and 29 have to do with this volcano . Its just questionable why these two microquakes occured from a depth of more than 30 km and not from somewhere between the suggested magma chamber of the old caldera in 08- 12 or more km depth and the seafloor. TECTONIC FAULTS BETWEEN TENERIFE AND GRAN CANARIA:The Tenerife Wochenblatt" wrote on Februray 02 2014, that already in 1989 , there was a " geological phenomenon on the fault ( deutsch: Verwerfung) between Tenerife and Gran Canaria, that led to as M 5.2 quake. This and the recent M 5.2 quake between El Hierro and la Palma on Dec 27 2013,- so spanish geologist ruled out , has nothing to do with the magma intrusion that occured at at the same time but " have their origin in an wider area". There was also yet a similar serial of quakes near Icod de los Vinos the expert also could recall. (The common plateau of all islands lies in a depth od aprr. 3700 meters below zero . Between Tenerife and Gran Canaria , the formations of both island form a kind of height in between , form which the seamount arises up 500 meters: however: this " volcano" sees not to have something like and opening or crater yet... activities on January 30- 2014:No further quakes below Hierro since more than one week. On January 30, Seismometers were shortly turned on on GranCan (with still the same signals as on Jan 29) as well as on Teneriffe and La Gomera: . ...but all machines were turned off again later on January 30. Today- Jan 31, at the time of this update , Seismographs were again turned off on Tenerife, Gran Canaria and La Gomera. ------------------------ Time to take a look also to other region in the world.Greece has been shaken by hundreds of afterquakes after an initial quake on January 26: The afterquakes reached magnitudes between M 4 and 5. The Greece administration has declared a state of emergency for the region of Kefalonia and Itaka, wellknown as the island of famous Odysseus (Ulisses) . On January 29 and 30 the number and strength of these swarm afterquakes significantly began to decrease. The Earthquake swarm in Puerto Rico had calmed down for a few days but resumed again on lower level after January 29, interestingly shortly after the M 2.7 quake had occured offshore the western coast of Gran Canaria. The earthquake swarm in the region of the San Andreas fault California, that had begun on January 08, still continues on low level with 3 quakes registered on January 28 those reached magnitudes up to M 4.0. While the main epicenters of these swarms first were around the greater Los Angeles area, a new Earthquake swarm began on Januar 29 in the Nevada desert region with a yet strongest M 4 quake located in about 100 km ( 75 mi) distance Northeast to Las Vegas:: more informations on global events and activities you find in my solar and terrestrial blog on my homepage Two microquakes occured also within the Eifel Volcano field near Koblenz/ Germany on January 28 and 29. Those microquakes had been rather seldom there but increased in the last years in number with magnitudes up to M 4 , not counted the numerous microquakes those regularly happen now also in a wider radius around Koblenz, where is the Laacher lake , believed to by the last active caldera resp crater of the Eifel volcano field . 2011 on major shockwave with M 4.4 occured in the wider Cologne area:, what was the strongest event, that could be felt on the surface People reported " it was like a van or train moving below them" Geoilogists who examined voluntarely ( there is not anything like a survey station there) the lake of Laach, observed bubbles of CO2 rising upform the seafloor to the surface and concluded that also this supervolcano in more than 30 km is currently more active than usually. The CO2 and carbonacid emission are likely the effect uprising hot magma has on carbonites it comes by and heats up on his way (stone material which is very common in the Earth curst and consists mainly out of Calciumcarbonite) Similarly as in an cement factory, the heat of the magma causes a chemical reaction in it: it likely oxidizes " burns" the chalk, what sets free CO2 , But noone in Germany would ever serioulsy believe, that there would be any current danger risk with their "supervolcano". -------- ----------------- Thursday- January 30- 2014Today, seismographs were also turned off now on Gran Canaria now. However: even most of the experts rather wonder about the strong signals the Seismographs on the islands sometimes write: que pasa, hombre?^ Gran Canaria`s seismograph was turned off today. ------------------------------Wednesday- January 29- 2014update/ 21:45 UTC: Another quake occured today outside of El Hierro, three days after an M 2.5 quake had occured on January 26 near to the Eastern coast of Teneriffe This time its center was near the island of Gran Canaria: In the afternoon of Jan 29, tremor signals sauddenly changed from the stronger harmonic tremor, that continued for more than two weeks into kind earthquake signals. Has the time come when the Magma begins to rise upwards from the big chamber in the depth into the volcanic formations of the island? As it seems possibly not?! Yet. this quake came form a depth of 35 km ( thats pretty much near the Earth mantle). The last one near Tenerife on Jan 26 was in a depth of 32 km.
No more quakes since January 26. Seismometers are still turned off on Tenerife and La Gomera. Gomera was turned in in the afternoon and has still stronger tremors, as well as Lanzerote und Fuerteventura.. Tremors Signals have much changed and are stronger now on Gran Canaria . I don`t have yet any explanation, what its means and what is going on there. I will be back as soon as have more informations. ^ Gran Canaria- 20140129. ^ La Gomera- 20140129. time to look also on the GPS/ deformation data: Deformation on El Hierro remained stable without further uplift since around January 12. The entire island was lifted up for more than 20 cm by gravitational expansion forces on the uprising magma since the last crisis in March 2013. Fortunately, as it seems - and as the graphic below seems to indicated- the lifting up process must have been almost equally on the western and eastern side of the island , as measured in La Fontera and El Pinar. So tourist must not fear, to get no sleep at night, as their bed might by declided to the one or the other side... The instruments for GPS deformation monitoring are produced by a company named TRIMBLE Essen/ Germany: ^GPS receiver by Trimble geodetic antenna for 4 D deformation monitoring (four dimensional control: height/ length/ width /and time axis) Here first some explications what the GPS data and terms in these plot mean : I have not found any source yet that explains the mathematic terms used in these plot Her the latest GPS plot as posted on AVCAN and IGN/ Spain: The two reference points in the graph above are La FONTERA in the South West of the island ( El Golfo valley) and El PINAR on the opposite Northeastern side: Here the latest GPS plot as currently posted on AVCAN and IGN/ Spain: and here the "rapide plot that can be found on volcano discovery/ El Hierro: the upper graph (E/W/m) means: East West deformation, the middle graph means(N/S/m): North /South deformation. The third below means (U/D/m)" Up/ Down deformation m = meters -----------------------------------------------Tuesday- January 28- 2014Nothing has changed so far. Tremors continue on a lower level on all islands. The seismographs on La Gomera and Teneriffe stayed turned off, or are not online. Quake signals from the deep followed recently all two days . The last one was recorded on January 26 - unusually near the Eastern coast of Tenerife . They are the only indicator, whether still magma is rising up from the hotspot into the deep magmachamber (as I would guess, somewhere in the middle of the islands). So here the lates thermal image of the islands by MODVOLC- published on January 28- 2014: ( the heat signature was relatively strongest first on Tenerife ( but was visibly there first only on its Northern flanc , Afterwards so from Jan 08- 12 on, it creaped also over the peak of El Teide.) and has increased since then also on most of the islands. . Latest and after January 08- 12 also La Palma volcano peak turned more and more into red ,. A wink of red colorisation became also visible since Jan 08- 12 on El Hierro, that had no heat signature at all in early January. Since January 12, the intensity heat signature remained almost equal since on all islands. previous image ( I don`t have copied a previous one) so here the last previous thermal image I have Its from 2014012: So: It remained equally since then, (but was less prior to Jan 12) Time to take a look to other places in the world: As a new record since years, 7 volcanoes are currently active along the western coast of Central and South America (source: GVP) . 4 of them are on red alert level: - Pacaya ( Guatemala)- San Miguel (San Salvador)- San Christobal (Nicaragua)- El Misti (Peru) three others are on yellow alert: Colima (Mexico)- Fuego (Guatemala)- Puyehue Cordon Caulle ( Central Chile) > Sinabung Volcano on Sumatra, that went "pyroclastic" since November 2013 even ramped up its actitiy in January 2014 (see video below)-------------January 27- 2014no changes compared to previous days / keine Veränderungen Tremors signals continued to decrease on all islands since January 24. The seismographs on La Gomera and Teneriffe had been turned off most of the time since January 25 out of an unknown reason, no matter, whether the most might assume then, that the officials want to hide anything. Recently an investment group had asked an US geologist to analyse the strong tremor signals those where measured on the most islands- and had been strongest on Tenerife since begin of the new volcanic crisis since Dec 22/ 26. ( you find this video at the end of my latest blog January 20- 27- 2014. She came to the conclusion that the tremors she examined ( Dec 22- Jan 06) are indeed an indicator for magmatic intrusion and heat effects Also she stated , that the Seismographs on several islands had been regularly turned off since begin of the new volcanic crisis on December 22/ 26. This might have be done to avoid panic among the vistors, since tourists numbers have significantly decreased significantly after 2011, when the new and unexpected activitiy at El Hierro initially had begun....( to be continued below>) . activity report- end---------- ------------- CANARY ISLANDS - ACTIVITY IN 2014 ...to be continued... . A Spanish geologist working for INVOLCAN told me already in 2011 ( via comments on the you tube channel of CabildoEl Hierro), that- after the BBC geologists have found that crack running through the Southern part of La Palme, resp. since BBC had broadcasted a report which says, that a volcanic eruption of Mount Teneguia on La Palma might trigger a landslide with a subsequent catastrophic Tsunami that would hit the European and US coast, he and many Spaniards feel or think to be victims of a conspiracy. ( by British and US Banks and insurances...) Prior to something like any eruption would occur", so the British and US Geologists had also ruled out in this report," there would be warnings signs and early enough, that there will sufficiant time" to warn or- of necessary evacuate the islands. But the way, the Spanish administratioon manages the volcanic activity would give me less trust in that . There are any kind of international agreements also that Spain has to publish its Earthquake records on an international level, the Spanish rather unwillingly fullfill. On January 25, the Seismograph obviously was turned on just for some minutes likely to claim to non experts, there was no tremor at all. while La Gomera and Tenerife likely have still the strongest signals of all islands. . Al least the storms on January 25 would have caused minimal tremor recorded on the seimograph of Teneriffe( as it is oftenly claimed, to "explain" the tremors in general ) However the expert said, that it must be turned off if it has no signal at all. However, at the moment and due to the Canary islands volcanisms"characteristics, in those volcanoes a lot of magma can accumulate without an eruption will take place at all and even any activity sign becomes visible anywhere on the surface (such as any steam emission ) would become visibly at any time. On the other side, any eruption in those types of volcanoes- so the most experts agree on- might occure if than without much prewarning and would be rather intensive and long . As higher the amount of magma below the island as stronger and longer an eruption also would be. Such an eruption for sure would produce high amounts of gases and smoke over longer time. The hot spot magma, that rises a up form the earthmantle is usually very hot and fluid but contains no gases ( what makes magma explosive) But as the new crater which grew up S of El Hierro at the end of the first new activities in 2011 demonstrated , it might mix to another compound if there would exist other existing magma chamber closer to the surface, as it was also mentioned also by the Spanish geologists. ------------------------------------------------------------------- So we have three possible scenarios: 1. the magma intrusion stops at this depth of about 10 km where it is now: the activity ends and the magma that already was pushed up (can`t get back in the earthmantle anyway!) would with the time cool down and harden out. >>Crisis over 2. second ( most probable scenario and considered by most experts, if the intrusion continues now or in the next future ): The magma ( if the intrusion continues) would rise further up to secondary magma chambers below the islands and their volcanoes, where it likely would mix with water and other incredients to an explosive mixture, what then triggers an eruption. Some sources such es el hierro blogspot mentioned that those higher magmas chambers are indeed considered to exist below several or all island (excluding the calderas) , In this case, continuing quakes from lower depth than 10 km would be a certain prewarning sign... But: Do the single islands have magmas chambers? ( read more below) 3. Scenerio ( rather unlikely) . The magmachamber in the depth has such a quantity , that an eruption would occure without any external force or gas , but occur, if the amount of magma grows so big and the magma level will also reach a point when the pressure it creates cannot anymore be contained by the crust above. This" beyouncy effect" is known to be the mechanism of supervolcanoes but its not sure yet whether it not might become also effective in other large but smaller magmachambers. However: the Canary volcano system is anything else than one of the tiny ones on that planet, since Teide is known to be the third largest volcano in the world. ----------------- ... Calderas: Does any of the Canary Island volcanoes even have still anything like an intact magma chamber? volcano modell with magma chamber (wikipedia) Shield volcanoes and Strato volcanoes: Hot spots with their hot fluid and gasless magma content mainly form so called "shield volcanoes, as that magma just can flow longer distances. Those volcano shields can be extremely hard, thus new activities mostly create new craters at the edges of the old shield, where the resistence is low enough, that the magma can penetrate the shield Scientists examining the Yellowstone caldera found out, that the volcano would perform a regular major eruption just as the Earthcrust moves above the hot spot to new locations with an intact earth curst , where the pressure increases then, while the hot spot has to create - if active- a new magmachamber, that soon collapses then with that first strong explosion, ( see video below blog ) However- due to the regular tectonic shift such a process needs hundred thousands of years ( in case of the Yellowstone appr 400.000 y.,), until then the hotspot might still be connected with its old caldera. But what- if the tectonic shifts accelerates such as by a meltdown of the polar icecaps ? (whereby at least the Northern icecap works also like a clue between the main continents Eurasia and Northern America. In case of the Afar fault such a process became already obvious and started just after 2005! Does anyone know, why this happens now? In case of the Canaries, this seems to be very similar, since it is known that the volcanic structures were regularly destroyed during volcanic events in the past and caused a binary form of volcanism- partially hot spot craters as well as magma intrusions through old destroyed parts of the previous systems , where the hot fluid and gasless magma then mixes with other "ingredients" but also with water to rather explosive and finally fragile materials as known from the most volcanoes. Differently to that, Stratovolcanoes" those likely seem to be fed by hotspots and byhot spot magma chambers, but formed out own magma chambers high above the hot spot chamber , where magma mixes with other ingredients to rather explosive mixtures , thus they build rather high cone of rather mixed and fragile volcanic material -------------------- VOLCANIC FEATURES ON THE CANARY ISLANDS:How many of the Canary vulcanoes are calderas? <^Map of the Canary Islands
Most of the volcanoes on the islands are regarded as "Calderas" such as La Gomera , Caldera de Taburiente ( La Palma). There is a discussion about the dramatic 10 x 17 km Las Cañadas caldera, which is partially filled by 3715-m-high Teide stratovolcano, whereby shield and shift volcanoes oftenly from several craters on the edge of elder calderas. CANARY VOLCANOES: GRAN CANARIA: Pico de las Nieves/ Gran Canaria About Pico de las Nieves (GVP) "The largely Miocene-to-Pliocene island of Gran Canaria in the middle of the Canary archipelago has been strongly eroded into steep-walled radial gorges called barrancos. Three major volcanic structures form the circular 60-km-wide island, which has been modified by caldera collapse, gravitational edifice failure, and extensive erosion. Middle Quaternary scoria cones and lava flows are found in the northern and eastern parts of the massive shield volcano, which is cut by a major NW-SE-trending rift zone that extends across the island and fed flows primarily to the NE. Very young basaltic cones and lava flows of Holocene age are situated within a NW-trending zone from Berrazales to Bandama and at Las Isletas, a peninsula on the NE coast. One cinder cone was radiocarbon dated at about 3000 years before present, and other cones and flows may be less than 1000 years old." ----- TENERIFE:El Pico del Teide ( Tenerife)For me ( and I am not an educated expert!) ^Teide looks pretty much like and intact volcano and not like a caldera. The Smithsonian GVP decribes it as an intact Startovolcano: Mount Teide/ Tenerife ( description by GVP): The large triangular island of Tenerife is composed of a complex of overlapping Miocene-to-Quaternary stratovolcanoes that have remained active into historical time. The NE-trending Cordillera Dorsal volcanic massif joins the Las Cañadas volcano on the SW side of Tenerife with older volcanoes, creating the largest volcanic complex of the Canary Islands. Controversy surrounds the formation of the dramatic 10 x 17 km Las Cañadas caldera, which is partially filled by 3715-m-high Teide stratovolcano, the highest peak in the Atlantic Ocean. The origin of the caldera has been variably considered to be due to collapse following multiple major explosive eruptions or as a result of a massive landslide (in a manner similar to the earlier formation of the massive La Orotava and Guimar valleys), or a combination of the two processes. The most recent stage of activity beginning in the late Pleistocene included the construction of the Pico Viejo and Teide edifices. Tenerife was perhaps observed in eruption by Christopher Columbus, and several flank vents on the Canary Island's most active volcano have been active during historical time. back to " Caldera">>> The thing is The term "Caldera" means a volcano thats magmachamber anytime has collapsed - likely during a major eruption: So- if there is not even any magmachmaber on these islands- Where and how could such a big amount of magma ( that has gathered anywhere below in a depth of at least 8- 10 kilometers?( to be continued below) Calderas would or even cannot not erupt in the same manner like intact stratovolcanoes would., as there is no storage for a larger amount of magma anymore. Caldera can remain nevertheless active, at least if water enters the former magmachamber, easily heats up in there and comes out again in form of steams, steam plumes or geysirs.(compare: Yellowstone). If new magma would rise up inside a caldera it has at least to overcome the resistence and weight of million tons of material that filled up the previous magmachamber, what would also create a noxious composition of ejecta. Last not least it cannot built up real pressure anymore, This is why calderas are rather not regarded to erupt again in any explosive manner LA PALMA:Cumbre Vieja ( La Palma)La Palma ( By GVP): The 47-km-long wedge-shaped island of La Palma, the NW-most of the Canary Islands, is composed of two large volcanic centers. The older 2426-m-high northern one is cut by the massive steep-walled Caldera Taburiente, one of several massive collapse scarps produced by edifice failure to the SW. The younger 1949-m-high Cumbre Vieja, the southern volcano, is one of the most active in the Canaries. The elongated volcano dates back to about 125,000 years ago and is oriented N-S. Eruptions during the past 7000 years have originated from the abundant cinder cones and craters along the axis of Cumbre Vieja, producing fissure-fed lava flows that descend steeply to the sea. Historical eruptions at La Palma, recorded since the 15th century, have produced mild explosive activity and lava flows that damaged populated areas. The southern tip of the island is mantled by a broad lava field produced during the 1677-1678 eruption. Lava flows also reached the sea in 1585, 1646, 1712, 1949, and 1971. ^Caldera Taburiente ( La Palma)http://www.igme.es/internet/actividadesIGME/lineas/GuiasGeo/taburiente/index.html EL HIERRO:El Hierro (by GVP) 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." LANZAROTE:The 60-km-long island of Lanzarote at the NE end of the Canary Islands contains the largest concentration of youthful volcanism in the Canaries. Pleistocene-and-Holocene cinder cones and lava flows erupted along NE-SW-trending fissures are found throughout the low-altitude arid island and on smaller islands to the north. The largest historical eruption of the Canary Islands took place during 1730-36, when long-term eruptions from a NE-SW-trending fissure formed the Montañas del Fuego and produced voluminous lava flows that covered about 200 sq km. The lava flows reached the western coast along a broad, 20-km-wide front. The villages of Maretas and Santa Catalina were destroyed, along with the most fertile valleys and estates of the arid island. An eruption during 1824 produced a much smaller lava flow that reached the SW coast. Mnt. Cardon ( Fuerteventura) Fuerteventura (by GVP) Pleistocene and Holocene cinder cones and lava flows cover large portions of elongated Fuerteventura Island at the SE end of the Canary Islands. The youngest lavas are found at the northern and central portions of the arid, sparsely vegetated island. Malpais de la Arena, the Northern Malpais, and the Lobos Island areas at the northern tip of Fuerteventura are the sites of broad fields of youthful cinder cones and lava flows. The Malpais Chico, Malpais Grande, and Malpais de Jacomar areas on the south-central part of the island represent smaller zones of youthful volcanism, as do the volcanoes of Pajara, which were constructed on the older plutonic massif west of the axis of the island. No historical eruptions have occurred on Fuerteventura. although the very youthful appearance of lava flow surfaces in the central part of the island suggests a late-Holocene or prehistoric age." ----- --------------------------------------------------------- SHIELD VOLCANOES:Shield volcanoes form new craters at the edge of their extreme hard volcanic shield Mauna Kea, Hawaiʻi, a shield volcano on the Big Island ofHawaii Nevertheless especially hot spot systems for sure might be able to create new volcano systems from their primary magmachambe rin the very depth , as it is suggested to exist anywhere below the island. It already did so when forming the new crater at the edge of the El Hierro shieldvocano in 2011. Hawaii`s Kilauea is another good example for such a reorganisation ; Kilauea is situated at the eastern lower flank of Mouna Loa , once a monstrous volcano still considered along with its neighbor as the largest and highest volcano formation on Earth: ^landslide mosaic of Hawaii with Mauna Loa in its center and the much smaller Mauna Kea in its North, which is now the highest peak on the island and allhough its mighty cone at least partially collapsed to a deep caldera , . ( By the way such a collapse happens actually as it seems at the Sinabung volcano on Sumatra. You find regular video updates here) This is known especially on shield volcanoes, where often new crater arise at the edge of the hard shield Does the Canary hot spot have a deep common "primary" magma chamber? That there must be some deep and larger magma chamber- that- as I would guess- most likely is situated NOT directly above the hot spots itself which currently is most likely directly below or not much South East of El Hierro. Not only the volcanism on all islands speaks for the idea that it would if then be somewhere in the middle of all islands and- as I just would just guess- might be centered somewhere rather to the Southeast of Teneriffe.(?) the mante plume earthquake distribution below El Hierro. In the search for the magmachamber in Yellowstone nationalpark , a 3 D model of upcoming tremors and microquakes was used first to localise the magma chamber. Later it turned out, that thenresulting model represents the form of the mantle plume,. The magma chamber of the Yellowstone begins about in a depth of 8 km. The size and depth of the magmachamber on the Canaries is not known. Its just sure that its within the Earth crust. So when the hot spot is stationary and tectonic plates drifted mainly to the West, ( there was a sugessted north south movement of the entire crust in the past as well, that cant be considered here ) an old existing magma chamber might have been left behind in North Western direction of El Hierro somewhere right in the middle of todays Atoll but not directly below of El Hierro. However - during the examination of the Yellowstone caldera ( there is a very interesting video about at the end of the previous blog) it became obvious, that it is at least so deep that it cannot be mapped or monitored by today`s means. Differently to the mantle plume, the Magma chamber does not send any tremor signal to the surface and identified in the animation modell as a the empty hole surrounded by tremor localisations. This 3 D Model of the earthquakes below El Hierro was made back in March 2013 . ( For myself) its does also not look much like a chamber but rather like a tube: WON CONCLUSIONS: The mantle plume - so the oftenly widening channel is called , that leads from the depth of the hot spot in the earthmantle (40- ? km. deep) into the crust has rather formed out in an oblique manner bended towards the West ( here rather the Northwest) Some sources as Mr Betzwiesers el hierroblogspot , who van better understand Spanish have already have refered to, that the existence of such a larger magmachamber was especially considered by Spanish geologists. I would doubt that this mamga has netered yet any of the magmachambers of the ilsnads single volcanoes and the heat signal they make on MODVOLC are currently maybe just hot gases rsing up from that large central Magmachamber . If it would trise further into these higher magmachambers or into the volcanoes , tremors would likely be measured from all around the affected island(s) The entire amount of Magma and where the magma since December 2013 actually is resp. has flow to since December remain to be the most "burning" and important , but unanswered questions. EL DISCRETO however remains a secret and what it naje means: the hidden, the silent one... . ---- --------- HISTORICAL ERUPTIONS OF MT TEIDE:the last historical eruptions of Mnt. Teide took place in: 1492/ 1706- 08/ 1998; 1909 ( GVP). The activity period beginning in the early 18th century was the strongest activity on Mnt Teide reported in recent history. ( I recenbtly found an very instersting Guanches report on that I tried now to find again but could not yet find again. I will post that, as soon, as I should) Most interestingly this activity period with its last major event in 1798 occured occured at the same time when a similar eruption period is reported to have occured on iceleand, which was with the eruption of Mount Laki, that killed thousands in 1783, also likely the strongest in recent history. Further reading: Icelandic Volcano Caused Historic Famine In Egypt, Study ShowsThe latest activity report by the Global Volcanism Program for Mnt. Teide- a shorts yellow alert state-dates back to 2004: Local volcanologists reported that there was increased seismicity at Tenerife in mid-May, according to a news article. The article stated that during several days before 18 May there were "five successive low-intensity earthquakes in the island's most volcanically active zone in the area between Mont Teide and Santiago del Teide." The director of the Estación Vulcanológica de Canarias stated that the earthquakes, which were less than M 2, could be an early sign that something unusual was happening at the volcano. Yorkshire Post Today News( by Volcanolive/John Seach) 2005 Volcanic activity Volcanic unrest occurred at the volcano in January 2005. Carbon dioxide emissions rose from 75 to 354 tons per day, and hydrogen sulfide emissions rose from 35 to 152 tons per day. Seismic activity remained elevated under the volcano. Fumaroles increased in pressure, and emitted sounds. There was no significant ground deformation recorded. 2004 Earthquakes Seismic activity increased at the volcano during April and May 2004. Over 200 earthquakes from magnitude 1 to 3 were recorded, with three being felt by residents. Most earthquake epicenters were centred around the NW rift zone of Tenerife and in the strait between Gran Canaria and Tenerife. The earthquake crisis was probably related to dike emplacement at 3-4 km depth. --------------- -------- Other volcano- news: my subject next week: WHAT HAVE SOLAR PROTON STORMS DO DO WITH HOT SPOT VOLCANISM? I will explain it, if the next solar proton storm should occurre. Its not a very complicated solar phenomenon, but rather new for science ( detected first in 2005) and yet barely explored but mainly unknown in the public . I stumbled over these paradox solar phenomenon while documenting this 24 th solar sun spot cycle and the huge NASA project launched for this event. And soon it turned out that these strong eruptions (indeed the strongest known activity yet within the peridocal fluctuations of the Sun`s activity called " solar irradiance" )have different to all other typed such as even x 20 flares, prominence or filament eruptions and their sometimes associated mostly negatively and neutral charged CME s a strong impact on Earth with allossible and thinkabve scenarios and effects. I cannot count them all up. All energetic processes are finally a consequence of an inbalance between Protons electrons- in other words: between the two antagonists (1)" cinetic energy "( the electrons) and its counterforce (2) "contraction" or what is know as gravity force (here the protons). The chinese call it just " Yin and Yang" .its the general process that drives also all processes in and on the Sun. So regarding those particle events" or "SEPs" in an first - and still one and only article , NASA published to the phenomenon after it was discovered by satellite observation in 2005: best with the word " They can do everything!!" ( remark the sentence "they can do everything" is either on th audio tape or it was erased from the article later not to frighten the public. ( NASA first only was ordered to examine solar influences on satellites and opther technical installation, but towards the end of the program they also began to realize the intensive climatical effects ( so called mainly polar temperature anomalies) SEPs have if they impact on Earth. I must search for this first article relased in 2013 and will post it soon here and on my HP) Here the article in 2005 : However, protons of solar proton can have velocities of more than the half speed of light and impact with an intensity of 10- 1000 pfu ( particle flux units / 1 unite = 1 particle per second per square meter) fully in to the geomagnetic field, where they. As theyse hydrogen cores are just protons and have no electron with them, they have immidiate strong interactivity and an unrestistable magnetic pull on each other , if they meet Electrons in the geomagnetic field . They associate to the electrons those circle along the longitudenal magnetic field lines around the Earth core to be continued in two weeks ... | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Jan 15- 19- 2014
letztes Beben(Kanarische Inseln ( IGN) Bebenmap( El Hierro) Mnt Teide ( Teneriffe) related free online sources:VOLCANOES: "Eruptions that shook the world" a very interesting and freely avaible source how volcanoes work where you find all what you want to know about volcanoes Sources of the volcanic activity at El Hierro ( since 2011): Some may like to read a review on the volcanic activity below El Hierro in 2011: Here is a data based report by earthquake .com- an excellent site regularly reporting (what you never get in the news) about Earthquakes and related volcanism worldnews.com: Special environmental reports about the Canaries Miscanellous: Geschichte Teneriffas (deutsch) |
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