Talk:La Palma

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To 81.39.114.134 - whoever you are. The name of the island is LA PALMA whether in Spanish or English - Palma is a town in the Balearics. SO LEAVE THE NAME ALONE. Also please note I happen to live on La Palma, I am a Geologist and Volcanologist speak excellent English and assure you that your "anglicanisation" of La Palma is WRONG. The Geologist (talk) 18:12, 4 May 2008 (UTC)

How soon before it fails - indeed will it fail?

I write as a geologist and volcanologist who is involved in studying the Cumbre Vieja on La Palma. Whether a future eruption will cause the western flank of the Cumbre Vieja to fail en-masse in a massive gravitational landslide is a hypothesis. The following facts are pertinant:

1. The Cumbre Vieja is currently the most active volcano in the Canary Islands and last erupted at the Teneguia vent in 1971. 2. During the 1949 several low magnitude earthquakes occurred. 3. Rubio Bonelli (1950) visited the summit region the day followingthe earthquake and reported the occurrence of a fresh fissure approx 1 m wide, with a maximum vertical displacement of 2 m and a visible length of about 2.5 km. He further reported that "... No fumes, ashes, lava, steam or other products were emmitted from the fissures ..." 4. Conclusion drawn from this is that whilst an earthquake occurred and may have been due to water becoming superheated; the water did not vapourise as there was no evidence of any phreatomagmatic explosions - which would occur if the waters had flashed into steam and broken through to the surface. 5. The dimensions recorded in 1949 accord with those recorded over the past 10 years by myself and others. In other words the area is stationary and has not moved since 1949. 6. If the hypothesis of Ward and Day (2001) is correct that the 1949 earthquakes indicated that failure of the flank has started, then it will take many more eruptions to split the Cumbre Vieja along its length of 25 km. It will also then require many more eruptions to move the same flank westwards to the point where it would be unstable. At that point the western flank may fail en-masse in a massive gravitational landlside and generate a so called "mega-tsunami." The Geologist (talk) 16:53, 16 March 2008 (UTC)


Contents

[edit] Random old comments

what happened during the civil war ?

that megatsunami stuff is disputed - here it presented as 100% likely

I reworded the megatsunami secion to make clear it is in dispute. Johntex 18:54, 30 Dec 2004 (UTC)

"During the 1949 eruption the western half of the Cumbre Vieja ridge slipped several metres downwards into the Atlantic Ocean." This statement is UNTRUE. Present the geological evidence or remove this lie. Brian

[edit] The Volcano section is not NPOV

The Volcano section is not neutral; words such as "falsely" and "publicity-seeking" should not be used, as they are expressions of opinion, not fact. Please correct the problem. -Rcnj

yeah the previous changed version wasn't that good either, sure you can't agree with the theory but to go the other way and say the scientists are bad and all isn't the correct way either. i have put the old version back, which shows the theory isn't unchallenged. Boneyard 22:22, 20 February 2006 (UTC)

[edit] The information about the La Palma Tsunami is incorrect

The 'western half' of La Palma did not ABSOLUTELY NOT 'slip 4 meters in 1949. This is a proveable lie propogated by the press on the basis of an interview with the boss of one of the scientists. Please remove this LIE, or produce scientific evidence to support it. You will have to look hard because there is ZERO evidence to support this claim. The ONLY physical evidence of any problem is a small, very schallow, surface crack 2km long which was caused by local subsidence.

The 1949 opening I work on La Palma as a geologist and can assure you and indeed anyone else that the volcano DID move in 1949. The details can be checked in Rubio Bonelli 1950. However the details which have not changed by 2008 are as follows: length of rift = 2.5 km, width of opening 1 m and maximum vertical displacement is 2 m. The eruption was accompanied by earthquakes which are thought to be indicative of edifice failure and are quoted as being proof that the Cumbre Vieja is "about" to fall into the Atlantic Ocean. I suggest you also read the entry for the Cumbre Vieja. The Geologist (talk) 16:23, 16 March 2008 (UTC)

[edit] Corrections to the Cumbre Vieja story

The information in the BBC Horizon program is based on the work of 2 scientists whose motives are highly suspect. At least 7 other reputable scientists have torn holes in the BBC story and the suggestions in the program have been discredited. There is NO scientific basis for their ridiculous claims. A co-author of the original work has branded their claims as ridiculous and not based on scientific fact. Boneyard: Please do not change the essence of this text back to the incorrect repeating of the media hype unless you can PROVE that there is scientific evidence. The words "falsely" and "publicity-seeking" are in my opinion accurate, but I appreciate that they might not be appropriate. We need to put this information into perspective without giving too much credence to a program that was effectively a work of fiction. Brian

[edit] INCORRECT INFORMATION : INFORMATION NOT VERIEFED AND NOT VERIFIABLE

I have to repeat this and request that the person who keeps re-publishing the completely unfounded and incorrect statement that "During the 1949 eruption the western half of the Cumbre Vieja ridge slipped several metres downwards into the Atlantic Ocean" STOPS presenting this LIE as Fact. It is NOT a fact, It is a complete falsification.

OBEY THE RULES. SHOW that this statement is VERIFIED. Otherwise remove it. The only evidence of any movement at all in 1949 is "a small surface subsidence crack at over 1000m above sea level". This was almost certainly caused by post-volcanic magma chamber collapse and is very localised - 4m deep and traceable over a length of 2km. It is NOT a vertical slippage fracture. It is NOT evidence that a block 25km long by 3km deep and 3km wide 'slipped'. It is more like the cracks in old paint which has absolutely no depth. For the published statement to be correct the crack would have to 25km long, show slippage of 4 meters at both ends (there IS no evidence of this) and the shoreline would have to have sunk 4 meters. This would place the current villages of Puerto Naos, Bombilla, El Remo and probably Tazacorte below sea level. These villages were quite clearly NOT under water when I looked last week. The land where the tomato plantation of an elderly aquintance of mine is also still at 5m above sea level, and has been since they were growing tomatoes there since the 1940's. The statement as published here is a proveable lie.

81.38.247.152 15:33, 21 May 2006 (UTC)

81.38.247.152 Has a good point. There is no evidence of a large scale slip during any of the eruption in 1430, 1440, 1585, 1646, 1677, 1712, 1949 or in 1971.[1] It has however, been suggested that a large scale slide could cause a mega tsunami. [2]

1. Pararas-Carayannis, G. 2002. EVALUATION OF THE THREAT OF MEGA TSUNAMIS GENERATIONFROM POSTULATED MASSIVE SLOPE FAILURES OF ISLANDSTRATOVOLCANOES ON LA PALMA, CANARY ISLANDS, AND ONTHE ISLAND OF HAWAII International Journal of the Tsunami Society Vol. 20 No. 5.

2. Ward, S. N. and S. Day 2001. Cumbre Vieja Volcano -- Potential Collapse and Tsunami at La Palma,Canary Islands. Geophys. Res. Lett. , Submitted.

Spahi 00:56, 24 July 2006 (UTC)

Well, we do cite a reputable source. It seems perhaps 81.38.247.152 might want to cite another reputable source that disagrees? Johntex\talk 02:53, 24 July 2006 (UTC)
Done. :-) (I'm not 81.38.247.152, just for the record.) Waitak 09:02, 11 September 2006 (UTC)

[edit] Cumbre Vieja vs. Cumbre Nueva

The article states in part:

[The Caldera de Taburiente] is surrounded by the Cumbre Vieja, a ring of mountains ranging from 1.6 km to 2.4 km in height. [...] Through the southern part of La Palma leads the ridge Cumbre Nueva.

This is incorrect. Cumbre Nueva is the northern part of a ridge going south from the caldera, and Cumbre Vieja is the (much younger!) southern continuation of that ridge, where active volcanism occurs. See [1] and [2]. (The latter article is also interesting as it estimates the extend of a tsunami caused by a future collapse of the western flank of Cumbre Vieja.) AxelBoldt 00:01, 25 May 2006 (UTC)

[edit] Junonia

Lanzarote is Junonia and not Palma Who the hell has stated that Junonia in Pliny the Elder is Palma and not Lanzarote (together with Fuerteventura)?

Proof 1:

Pliny mentions: "etiam spatia complexus Iunoniam abesse ad Gadibus DCCL p. tradit, ab ea tantundem ad occasum versus Pluvialiam Capriaramque".

Palma is the westernmost island of the Canaries and therefore in the west of Junonia there is no island of the Canaries (no Pluvialia and no Capriaria).

Proof 2: In Claudy Ptolemy the O-meridian is set through the westernmost island of the known world and this was through the Canaries. That means through Palma. But according to Ptolemy two islands of the Canaries are not in the 0-meridian but on the 1-meridian in the direction of Mauretanian coast and these are Lanzarote and Fuerteventura (Iunonia) and Gran Canaria (Canaria).

--213.55.131.22 17:38, 6 October 2006 (UTC)

Comment re "proofs": El Hierro is further west than La Palma, and can probably be easily seen from there; that is the island which was used for the 0 meridian. 89.125.136.233 (talk) 20:57, 4 May 2008 (UTC)

[edit] Reversion of ref removal

User:62.14.122.84 removed the following link to an article on the tidal wave theory:

I've put it back. The motivation is that a WP article should present a balance of information, with enough to let the reader draw his or her own conclusion. It's unacceptable to remove a reputable link because the editor disagrees with it. Waitak 11:46, 10 October 2006 (UTC)