The Rumble in the Jungle

The 3 volcanic peaks of the dormant volcano of Kilimanjaro. Picture by David Daniel Turner, used under Wikimedia Commons.

Africa in general is a place that is easy to fall in love with, in particular Tanzania is easy to become deeply enamoured with. Sometimes I think that there is a deep DNA-memory remnant in all of us that is telling us that this is our ancestral home.

When most people think about Tanzania, they think about the great national parks like Serengeti, Ngorongoro and so on, or perhaps Zanzibar Island and the allures of Stonetown. Some spend a day or two in the mega-city of Dar es Salaam, but few get to see the rest of the country. And it is a big rest indeed.

I have had the pleasure to travel there on 5 business trips in the last 7 months, due to time constraints I did not have the time to go to any of the obvious places that everyone goes to. More than a decade ago I got to spend a night in the Ngorongoro, but the company I was with was more interested in BBQing steaks on our campfire and imbibe on Konyagi than looking around. And we came late in the evening and flew onwards early morning with our post Konyagi pounding heads, so regrettably no chance to see that much.

If you go to Tanzania you must try out Konyagi, it is a local slightly sweet spiced spirit. It is not deadly strong at 32% (that would be 64-proof for the imperially confused). It goes down well mixed with pretty much anything, but it is especially good with Red Bull.

I was warned by the documentary film maker Michael Dalton-Smith that it would make me see blue baboon arses if I had too much. Something I can attest to after a night drinking with friends on the beach in Mtwara City, the full moon did indeed turn into a blue baboon arse.

Perhaps this is a good moment to move over to the volcanoes of Tanzania. After all, this is not a site for the scientific study of the Lost Blue Baboon Arse.

 

Mantle plumes

The crater of Ol Doinyo Lengai in January of 2011. Photograph by Albert Backer, used under Wikimedia Commons.

Up until a few years ago mantle plumes were a hotly (pun intended) contested subject. The reason for this was that the entire theory was based on the Hawaiian mantle plume and the volcanism caused by it.

This in turn led to problems as soon as you tried to use the mantle plume theory on other more diverse plumes, like for instance the Icelandic mantle plume, of the African plume derived volcanism.

In the end though it turned out that the initial plume theory was too simplistic and only fit a minor set of plume instances, and the theory was expanded to incorporate several types of mantle plumes.

And as science started to look for evidence for the theory, it came in leaps and bounds. In 2015 a research team used data from 273 large earthquakes and all of a sudden, we had tomographic pictures of two very large mantle plumes extending from the outer core boundary up to the surface.

One was in the pacific causing the Hawaiian volcanism, and the other far larger was under Africa. The data at this time was constrained by computational capacity (no high frequency data could be crunched), and the limiting factor of there being almost no seismic networks on the ocean floor leaving out roughly 70 percent of the surface of the globe.

Later more data was churned on more powerful computers using a larger earthquake data set, and smaller plumes turned up around the globe, either connecting to the core boundary, or starting mid-mantle.

So, what is a mantle plume? And how does a plume work? Well, here is where we run into a lot of “we do not know’s”.

The initial theory worked on the assumption that there was heat convection transferring heat from the core boundary upwards, and that this heat increase caused increased melt at shallow depth causing an increased volcanism above.

But what about matter convection, could not a plume theoretically move matter from depth upwards? The reason this question was asked was due to some rather annoying spots in the crust associated with plume tracks where you find inclusions of minerals that just should not be there, and that can’t be explained readily by metamorphosis of rocks in the crust.

Simba Hill rhyodacite dome in Dodoma. Home of the Yoderite.

As time went by the argument between the heat-conversionists and the matter-conversionists got a bit heated (yes, pun intended), since the heat conversionists demanded proof. The only thing we the materialists had going for us were the oddities, and the known speed of possible mantle material flow (2.5cm per year).

Let us now recapitulate, we had circumstantial evidence for mantle plumes in the form of tomographic pictures making plumes into a probably correct theory, but there was no direct evidence for mantle plume matter convection.

This changed on a particularly sunny day in Iceland. The answer had been around since 2002, but nobody had really understood what Kresten Breddam had done in the paper ‘Kistufell: Primitive Melt from the Icelandic Mantle Plume’.

Problem was that this was a paper in geochemistry about an unusually boring Icelandic volcano, and the paper turned into a dust-collector in the bottom drawers of science. Until it was pulled out during the weeks leading up to the Holuhraun eruption (by me).

Another reason this paper flew under the radar is that Kresten is not a volcanologist, instead Kresten works as a nuclear research scientist at the Danish Public Health Board (Sundhetsstyrelsen). Inter-disciplinary blindness is a bitch.

Kistufell is sitting at the centre of the Icelandic mantle plume, and in one of her samples Kresten found a crystal that had formed at 470 kilometres depth before being conveyed up to the surface. If there was a Nobel price in geophysics Kresten would by now have met the Swedish King.

Anyway, in my rambling ways I have now set up things for us to get acquainted with the African plume, or as it is called, The African Super-plume.

 

The African Super-plume

Simplified image of the African Superplume. Image by Brews O’Hare, used under Wikimedia Commons. Matter convection from the core boundary is constrained in the 2nd LVZ, and secondary matter convection leads from this point up to the crustal bottom in diluted form.

It got its super-moniker from its size and capacity. Even if you tally up the heat-convection capacity of all other plumes on Earth they do not come up to the heat transfer from the core boundary to the surface of the African Super-plume.

We do know that it is a fairly young plume, it roared into view roughly 30 million years ago as it caused a series of VEI-8 eruptions in Yemen, Saudi Arabia, Ethiopia and Eritrea. At the same time, it caused a number of flood basalts in the region, and it also started its career as a continent whacker as it separated Arabia from Africa by creating the Red Sea.

As Africa continued to move to the north it started to create the normal plume track, but it was just to large, and instead the plume divided into two distinct plume heads. The first one preferred the point of least resistance and continued to erupt through the Afar region. Lazy bugger!

Original poster for the Rumble in the Jungle.

The other one did something a bit more unexpected, it raced like the proverbial blowtorch out of hell south across the African continent cutting it apart into two continents. The part that is hard to explain is that the southern plume head moved at twice the speed of the continent.

As it moved south it created the Great Rift Valley in its wake, home of all of us. In a sense of it, we are all children of star stuff being birthed out of volcanoes in Africa.

In the end this happy giant blowtorch ran into a worthy opponent in the form of one of the densest, deepest and coldest parts of earths crust, The Dodoman Craton in Tanzania.

It turned into the true Rumble in the Jungle between two super-heavyweight champions. The ensuing blows has created among the largest volcanoes on the planet erupting incredibly weird lavas, a volcanic field containing hundreds of calderas ranging in eruptive size from VEI-6 to VEI-8, trap-formations, and even more continent busting.

In the beginning of this war the craton came up on top. It was just to deep, cold and hard to be greatly affected even by the jolly giant blowtorch. The plume head was though so large and powerful that it started to envelope the entire craton opening up battlefronts around it. One front marched relentlessly to the south-west, and the other one went towards the east and the ocean, pining to create an African Fiord.

The path towards the Indian Ocean has so far been tougher going since it too is quite thick and hard, but it will in the end succumb to the force and East Africa will be a continent separate from the rest of Africa.

And if that would fail, the Tanzanian plume head will just continue down the far weaker western side of the Dodoman Craton. The difference will just be that the Craton will then remain as a part of the future East African continent.

In the end though this fight is taking on even more of the characteristics of the Rumble in the Jungle. For those who are not familiar with the Rumble in the Jungle, it was the greatest of all boxing matches and involved George Foreman and Muhammed Ali dunking it out in the Democratic Republic of Congo.

Like Foreman the Dodoman Craton had the Tanzanian Plume against the ropes for tens of millions of years while it delivered endless series of death blows to it, but like Foreman against Ali, it had in the end expended its energy, and like Ali the plume started to hit back with blow after blow against the head. The difference is that this time there is no crowd shouting “Ali, Boma Ye!”.

The counter attacks started inside the edges of the cratons as volcanoes like Ol Doinyo Lengai erupted carbonatite lavas. No, Ol Doinyo Lengai is not unique, there are several dormant volcanoes sharing this feature in Tanzania, but I will get back to this.

And about 2 million years ago volcanism started to occur at the centre of the Dodoman Craton. A couple of weeks ago I visited Dodoma, the new capital of Tanzania. As the plane landed, I saw odd looking hill formations, and to my joy one of those was right behind my hotel.

As I ambled over to the hill, I discovered that it was a weather-worn rhyodacite dome roughly two million years old. This shocked me a bit since I did not know that there was mid-craton volcanism. After that I found something even more bizarre, but that is best left for another instalment.

Next article will be a brief list of the volcanoes in Tanzania as a reference for future more in depth articles about individual volcanoes.

 

Conclusion

To draw the analogy of the Rumble in the Jungle even one step further, in this match there is no referee. The level of monitoring is akin to being non-existent. Some might say that there has been comparatively little volcanic activity in Tanzania, but this is flat out wrong.

Roughly every ten years something will erupt, most often in the benign form of a bit of carbonatite ash from Ol Doinyo Lengai, but now and then something more dangerous will erupt.

Leaving volcanism on this scale un-checked and largely un-monitored is fool hardy. This is literally the only spot on the planet where a civilization decimating eruption could be building up and we would know nothing about it.

Obviously, there is no money in Tanzania to create a national network and a volcanic observatory, but something needs to be done. Question is just what?

CARL REHNBERG

112 thoughts on “The Rumble in the Jungle

  1. Great read thank you Carl🤟looks like you found one of your many happy ( most fav places ) in Tanzania.

    That plume haves high ammounts of melting and should only produce Thoelitic Basalt as Erta Ale do.
    But the further down you go from Etiophia the more alkaline and strange the magmas becomes.
    Kilimanjaro and Lengai and Congo are peak of alkalinity.
    Many Tanazania volcanoes erupts the Erebusian Antartic rift magma seriers.
    Kilimanjaro is basicaly a huge heap of Erebus like materials. The alkalinity is because the Craton is so thick? and causes small ammounts of melting deep down? The peak of Alkalinity ( most alkaline seems to be in Tanzania arera ) looks like my musings are correct.

    Did you knew that Lengais earlier magmas and tephras was infact sodium rich Nephelinites from a deep source of small ammounts of partial melting.
    It only recently started to produce carbonatite magmas. Most of lengais edifice is Nephelinite

    These are the most alkaline and strangest magmas on this planet! Great Rift is well known for sodium rich alkalinity in their magmas.

    • Jesper, do not confuse the primordial basalt parts of Africa with the Tanzanian part of the plume track, the volcanism that the plume causes there is so different that it could be on Jupiter for all points and purposes.
      So, let us please avoid gushing of basalts on this one since it will only confuse everyone and lead astray from the subject at hand.

      • Carl what Im trying to say
        Is it the thick craton in Tanzania that makes the magmas in Tanzania so very unusual and alkaline?

        Its right over the Superplume

        But there is a very thick hard litosphere on top.
        Is this why there are very alkaline rocks souch as Carbonatites, Nephelinites, Basanites, Trachytes, Phonolites, Tephrites and Tephriphonolites in Tanzania?

        Thick litosphere apparently cause small ammounts of melting and can make magmas as alkaline as they are in Tanzania?

        • Yes Jesper, all your questions are answered by the interaction of a large plume pumping primordial hot basalt into a craton melting in large number old cratonic crust into magma.

      • Since we are talking about the Tanzania plume area and volcanoes: here is another very strange fact for you to ponder on:

        In 2008 Ol Doinyo Lengai became explosive and did some subplinian action. The tephras where sillicate magmas nephelinite tephras of 2008.
        After 2008 a few months, then Lengai changed back to todays Carbonatite.
        Weird how it changed from natrocarbonatite to Nephelinite and then back to carbonatite again.
        Today its the Natro – carbonatite lavas again.

        This is so strange! but thats for another VC article and maybe its better to discuss this in the VC bar

        • The appearance of natrocarbonatite magma at Oldoinyo has to be a recent phenomenon for simple chemical reasons: sodium carbonate is water soluble, and that region, while fairly dry, is certainly no desert; a volcanic edifice so built wouldn’t last long enough to build any sort of mountain, it would simply dissolve into brown dust. Since OL clearly hasn’t so dissolved, it must obviously be built up from insoluble material – i e (somewhat) more conventional silicate lavas

          • One would think so, but there are actually more of these volcanoes than just Ol Doinyo Lengai. I will though get back to this at a later article.

      • Super interesting article Carl. Big thanks for the effort.
        Important question regarding monitoring of the volcanism. How does other poor regions (in regards to money) handle this. Could the Lundin minerals of the world be forced to be a part of it perhaps?

        • Yes, I think that some of the oil and gas companies could be coerced into giving a bit of a equipment, but the monitoring side of it they would probably not be interested in.
          Companies like that like to give a chunk of cash to a worthy cause that is tax deductible, but they almost never want to be a longterm partner in running the equipment, or for that matter take responsibility for the usage.

  2. Great article Carl – Continental crustal thickness is about 50km , the mantle is 2900km thick (according a quick google) so the chap findng minerals that actually moved up from 470km down is very interesting.

    The blowtorch cutting africa sounds like it needs a huge amount more investigation – but I’m surprised that mining companies have not done that?

    I’m guessing this book will have a bunch of info that may be relevant (it seems very thorough for the sections the preview allows – unfortunately not including tanzania) https://books.google.co.uk/books/about/Alkaline_Rocks_and_Carbonatites_of_the_W.html?id=K48ZMBWtoi4C

    I mentioned it before in https://volcanocafe.wordpress.com/love-or-the-library-of-volcanic-eruptions/
    but I guess that section of the old site never made it into the archives here (something for bored dragons to look at perhaps) 🙂

    • I am interpreting this as an answer about Icelandic crustal thickness.
      In Iceland crustal thickness ranges from 10km to 45km.
      In the Dodoman Craton the thickness is between 180 and 230 kilometres.

      In regards of mining companies, a huge quantity of mining companies are busing like bees around it. Blood diamonds? This is what caused them. Tanzanite? Guess why! And so on and so forth.
      You have them all from Anglo American to Lundin Mining…

      Definitely something for a bored dragon 🙂

  3. Great Article, Carl. Galloping hot spots are of interest to me because of the presence of Yellowstone in my genera area.

    • Welcome over one day to study one that is working more fertile ground.
      Yellowstone is not one of the smaller hotspots of the planet, but it is currently going into one of the less fertile spots of the planet.
      And there is always a need for pilots in Africa.

      • Yep, I almost got coerced into co-piloting a repo job on Idi Amin’s 737. This was with a Sky Pirate I knew-he ended up working for Evergreen?CIA? Somebody else took the job. My ex was mad at me for months..Never had mercenary inclinations. Left that to my Ex…
        Yellowstone’s is about to take a long a long grannie nap IMHO..

        • I thought that he flew out to Saudi Arabia on that airplane?
          How come all the nice people end up there? 🙂

          • Didn’t say the other guys were successful,either-they ended up in a Kenyan Jail for few months-probably saved their lives..

          • Did they try while he was in power???
            Jeebus!
            I thought it was after he was happily deposed by the Tanzanian army.

  4. Hi Carl,

    I quite agree with you that there is something seductive and wonderful about East Africa – and I can’t explain it either, so perhaps it is the volcanoes 🙂

    One small correction – the Maasai Mara is in Kenya, not in Tanzania.

    • You are quite correct, I was obviously thinking about Serengeti National Park.

  5. i agree with the dna memory of the relief of wide open spaces standing on the African velt and the involuntary crouch when a shadow passes over…. we are all Africans. The drums will beat it out for us. Waiting for more, Best!motsfo

    • There is a pervasive drive to groom our lawns to a similar appearance.

  6. Thanks for the write up. I know zippo about African volcanoes (and not much more about Africa). Interesting!

  7. Is this super-plume sib to recently confirmed monster beneath that Pacific mega-massif ?? Both seem to originate from very big, very old, very deep ‘blobs’ that have now mobilised. Possibly relics of very early subduction taking a lonnng dive ?

    FWIW, Yellowstone plume, like Naples area, seems to arise from a leaky slab-break. Different ‘interesting’…
    ( Speaking of grumpy geology, Albania’s Tirana’s just had a 5.x, but seems okay-ish…)

    Incidentally, some plots of Iceland’s hot-spot track show it swooping from Greenland’s High Arctic before meeting ancient suture with results we see.
    I’ve read the hot-spot is still creeping Eastwards with designs on Scandinavian craton. Is there any trace of path *before* Greenland ? Or was it all subducted ??

    • It is thought to be the Alpha ridge north of Ellesmere.

      Models with a stationary hot spot show a track down the east coast of Greenland, before cutting across to Iceland. The recent geothermal model has the track going down the middle of Greenland instead, but also from Ellesmere. This is funny because it means the hot spot was not fixed in between. We should be a bit cautious about this track. It may be right but the track along the east coast is more plausible.

      • Additionally, referring to Global Techtonocs 3rd ed, they note that hotspots maintain their relative spacing, but called an exception with Iceland’s hotspot when discussing them.

    • No, it is not related to the Pacific one.

      Over to Iceland. Against popular belief Alpha Ridge and Greenland has nothing to do with the Icelandic Plume. We can say that with certainty since we know when it came into existence roughly 15 million years ago.
      We also know that the Icelandic plume started at the top and is burrowing downwards as it goes, and this was the main battleline in the “plume-wars” that raged a few years ago in science. We do not know about any other plume with that baffling characteristic.
      And the “plume-track” between Greenland and Iceland is non-existent if you take a closer look, there is a deep through between them, and what looks like a track is just coincidence created by the expansion of Iceland pressing towards Greenland.

      Another point to ponder, Alpha Ridge was old even at the time of Alpha Ridge, it started out as the culprit for the Siberian Traps, so it either died off at Alpha Ridge, or ended up in a highly diminished for under Jan Mayen.

      Edit:
      The Icelandic Plume is not creeping anywhere, it is solidly welded to Iceland and if anything Scandinavia is moving away from it. That being said, it is pushing against the Scandian Shield and one of these days subduction will start there, and magma has already started to accumulate under Norway in pretty substantial amounts due to decompression melt. So, secondary effects yes, but no creeping crawly plume to be had. 🙂

      • Carl, like the nascent “subduction zone” off the coast of Norway (that is pushed by Iceland’s plume activity), could it be that the nascent “subduction zone” off the coast of Portugal be linked to the pushing effect of the older Azores hotspot?

        (Portugal has experience several tsunami events and M8+ quakes in the past 2000 years, the 1755 was just the most recent event)

        And my second question: could it be that the Storegga event was actually caused by one of those rare subduction zones instead of a submarine landslide?

        • At 5 km deep, the ocean off Portugal may be close to initiating subduction. But it hasn’t happened yet and I believe the M8 quake in the 18th century was associated with the fault that runs to the Azores. Not a subduction quake. Can’t speak for earlier quakes. Portugal is heavily fractured and there are many faults that can break.

          Storrega was a landslide. Volcanoes can cause landslides but it seems unlikely that happened here.

      • I would tend to agree that it developed from the surface, not from the deep. Probably a bit older than 15 million years since parts of Iceland are older than that, but it may have fluctuated in strength. I think it predates the break-up of northern Europe/America in this region (30-50 million years ago) but by how much is up to debate. At that time it would have been around the Baffin Bay. I don’t really buy the track up central Greenland, and what happened longer ago is conjecture.

        • I think the best way to date, since it would be the only testable way, would be by going with the oldest plume derived rock in Iceland at 14.6 million years. The rest is basically old uplifted oceanic crust of MORB-magmatic origin.

          I agree on not buying the track down through Greenland, if you detour that track in accordance with known tectonics you get a fairly sharp knee and the plume remnants should be around Jan Mayen. It makes quite a lot more sense and would be tracking better with known plate movements.

    • We did get a little jolt and some aftershocks, but minimal damage. Thanks for noticing. Any chance Albania could show up on VC for volcano-related reasons?

      • We are currently not planing an article about Albanian volcanism for the next million years or so. In other words, we do not think there will be anything volcanic happening in that time frame in Albania.
        The current seismic activity is purely tectonic in nature, and that can be terrifying enough without involving a volcano.

        • I went through the outskirts of Skopje a year or so after their big quake. Even tidied, it was a real mess, ‘trad’ and ‘modern’ buildings savaged. The region’s snarled tectonics don’t take prisoners, massacre ‘hostages to fortune’. And, sadly, thanks to the slo-mo mega-train-wreck of its North Anatolian Fault, Istanbul looks to be next.
          { Weep… }
          But, beyond some hot springs, scant volcanism. Such are else-where…

  8. Thanks Carl for another entertaining and educating post. Now I got an urge to visit Tanzania! Looking forward for more! And all new data on mantle plumes! Would be nice to see a post dedicated to that!

    • Plumes is on my todo-list…
      If you go, holler and if I am there we could have a Kilimanjaro Beer or two.

  9. Can anyone tell me what formed the unusual colouring of the Apple Crater in Iceland? I can’t find anything about it online and don’t know its Icelandic name. There is a fantastic drone video of it on Instagram (search using #applecrater – don’t know how to give the page). Thanks.

    • Kerið Crater is an old cone in Iceland, nothing odd with it really. The green is moss and the red is titaniferrous material from the MORB-derived lava.

      • There we go again with siderophilic elements…

        /Not to mention purveying fine merkins?

        • Nothing wrong with a little bit of healthy siderophilia among friends.

          Edit: In the name of spreading useless knowledge, siderophilia means that someone or something loves iron.
          Siderophile elements are various other elements that love to rub up to the sexy iron, like titanium, ruthenium, oxygen and so on and so forth…

        • Explanatory for all: In the back channel, I noted an article stating a phenomena claiming that at some point in the Earth’s past that titanium (a siderophile) levels in the Earths crust made a drastic change. The question that we had discussed was “What geologic phenomena matched the event in time?” Since titanium likes iron so much, the idea was that something caused titanium from the core region be delivered to the crust at an increased rate. No definate conclusion came about from our discussion. The end result was that “siderophile” became part of our recent vocabulary.

          • Yes, there could be a connection with mantle plumes, and as Carl noted, he will probably touch on that in the future.

          • I will do that when someone gets around to whack me over the head to write about Dried Plumes and Plume Compote. 🙂

      • I don’t think Kerið is the same as the mentioned “apple crater”, but the reason for the coloring is probably no different. I have tried to identify the crater, but without success. The only thing I found was that it’s supposed to be in the southern highlands. Obviously it is possible to drive there (although it might be illegal to do so if it means you have to go offroad). It kind of resembles one end of a red and green apple.

        https://www.instazu.com/media/2119994629265938014

        • When I googled it I came to Kerið, but there might be more of them. There are a few Laki tuff cones that also look like that. And a couple of Rauðholar (Red Holes) also has that colouring for obvious reasons.
          Regardless, the principle is the same, moss, titaniferritic material and a liberally increased colour saturation. 🙂

        • Wow! Fantastic coloring… i never have the sound up so i missed the flinging dentures…

        • This Apple Crater is not Kerid in southwest Iceland (from Grimsnes volcanic system)
          Offroad driving is forbidden in Iceland and punished by serious fines.

          But there is a crater, which looks a lot like this one in Veidivotn, which you can legally drive with a jeep up to its top (the jeep road is marked). I once did that and it took me 3 attempts to manage to climb with the jeep until the top. Because it was very steep.

          The crater is about 20min drive from Landmannalaugar and it is one of the first ones, coming from the west, in Veidivotn.

    • Yeah, I blame Bear Grylls.
      He undressed and clenched the ring between his butt-cheeks, dove from a cliff and swam nude 2km and proposed as he walked up the beach while hauling the ring out of his arse.
      Was just a question of time before someone tried to outdo him on the stupid level.

    • Wasn’t it he or one of his survivalist cohorts who ate the sheep that blew over the cliff? {Lord knows how long the sheep had lain at the bottom of that cliff before he found it}

      (The flying sheep was the origin of the Volcano Cafe mascot)

      • Yes, it was Bear Grylls.
        One very windy and stormy night during Eyjafjallajökull a sheep flew past a webcam at a good clip and fell down the almost shear cliff of Búrfell. Next summer Grylls found the poor sheep carcass, ate select rotten parts including the eyes, vomited profusely, and made a rather stinky sleeping bag of the skin.
        Somehow the flying sheep deserved better.

        How windy? A nearby weather monitoring station had winds equalling Dorian.

        • I experienced these winds frequently when I lived in Iceland.
          Even for a weatherman like me, it was crazy to experience those polar storms.

          Yes, quite regularly winds reach sustained hurricane strenght. And you can bet once per year, you will get a mammoth storms with winds packing near 200kmh gusts.

          Iceland is very very windy in winter. And this is because the contrast between the pole of cold that is Greenland, and the mild Gulf Stream.

          Add that to flying snow and flying volcanic particles, and you will seriously dislike facing head on during an Icelandic storm.

          Once I saw a flying tree (flying horizontally) near me. It was a small birch tree about 2 meter tall, but a tree nonetheless. Looked like a missile!

          But the Piteraq winds are even worse in Greenland!

  10. As many of you know, I am fairly well versed on technology. Despite this, I have a strong Luddite trend in my approach to it. So, a cautionary tale for you.

    Recently, I went to the store. Shortly after parking, my vehicle was hit by another one who was backing out. In my opinion, the damage was superficial, but real. Since the young girl accepted responsibility for the event, I opted not to contact law enforcement and traded insurance information with her. Her statement that her back up alarm didn’t warn her prompted my response to “never fully rely on technology.”

    And that brings up a note that is found on pretty much every nautical chart that I have ever seen. Printed somewhere on them on the margin is the following note; “WARNING. The prudent mariner will not rely solely on any single aid to navigation, particularly on floating aids

    This is a very real and very wise warning for all activity.

    As for GPS, well, that can get you in trouble fast if you over rely on it. It didn’t apply to the accident, but tales of bad GPS induced incidents are legion. Just for something to do one day, I took a GPS receiver and tethered it to my computer and recorded several hours of raw GPS data into a spreadsheet. The receiver remained stationary in my yard, powered by an external battery power source. Plotted, this receiver wandered all over my yard during the recording. Most significant in the data streams, was watching each satellite go “New Day” as each satellite reached the end of it’s day cycle.

    Understanding technology is one thing, trusting it is a whole different story. In the girl’s case, her vehicle had a back-up camera and warning system. It failed her. Had she also been using her Mk-1 mod 0 eyeball, she would have noticed the discrepancy in what she saw verses what the technology was not telling her.

    Am I mad? No. Inconvenienced yes, and a little bummed out. I was a bit amused at what I presume was her little brother who got out and watched our discussion. I assume he was showing support for big sister but she was so flustered that my concern was getting her to calm down. She asked about what she needed to do and I advised that she should contact her insurance carrier and they will take care of the rest. (We have the same carrier and I have experience with them. They are top rate in my opinion.)

    • Well, we all crap up now and then. The difference is that real people own up as she did, and are thusly easy to forgive. Then we have the fake people who do not own up to things, those are really hard to forget.
      After all, it is only human to make dodos. Lordy knows I do them all the time 🙂

      • Decades ago, I had the unfortunate experience of rear ending a lady up in Jackson MS. Typically, the person who hits someone in the rear is “at fault.” Fortunately for me, a Jackson PD officer was behind me and saw me trying desperately to change lanes to avoid the crash. Every time I did, she moved into it.

        And yes, I have even hit a pedestrian. Strange one there. She was cited as being at fault due to her high alcohol content. The only evidence the police could find that indicated that I may had made contact with her was a clan smudge in my otherwise dust covered car. If she had not stiff-armed my car, she would never have been injured. For this reason, to this day I am very weirded out when it comes to driving in fog. All in all, it’s not a bad paranoia to have. More useful than harmful. Of course that also lead to me violating a few DOT regulations with a driving light I used to have on my F-150. Angry at the meager light from the stock bulbs, I re-engineered a set of bulbs using a quartz halogen lamps cemented into a 367 bayonet base and sealed with high temp RTV. Good lord could that thing throw a beam of light. Probably upwards of a couple of million candle power. Had to rig a separate power and relay set to keep from frying the OEM circuitry. {Only used on the darkest of nights to get to the Fire-House on those early morning calls}

        • I am convinced that I am a crappy driver, so I tend to be rather careful when I mooch about. And, I drive sensible cars. No, the Koenigsegg does not count, I got rid of that after 50 kilometres.

          The only car like thing I have crashed was a Leopard 2, I was supposed to drive it out of the garage, put in a gear, looked straight ahead at the opening, and rapidly exited the garage in reverse. End of story, garage had a brand new opening that was not supposed to be there.

          Boats are flotational devices. A friend of mine loved wooden sailing boats. Several times he asked himself, where is my boat as he came to the jetty. We became quite adroit at salvaging his boat as the summer progressed.

          Edit:
          Come August and the boat in question had swollen shut and was a pretty good boat to sail on. Problem is that August is pretty much the time to pick up the boat in Northern Sweden. So, it dried up during the winter, rinse and repeat next summer. I have never seen a boat receiving so much caulking and still leak like a sieve.

          • I tried the wooden boat thing once. It was refitted and went through the same yard that had originally built it, and they did a spiffing job at making the ship tight as a fiddle.
            With the exception of a mystery hole on the starboard side. It was roughly a foot up on the side from the waterline.
            So, when tacking you had to make certain that you timed your legs so that the pumps had enough time to expel the bilge water that built up.
            That also solved itself as the hull got more waterlogged. In the end it turned out to be a ridiculously well built and well designed ship, after all it survived wave-surfing a hurricane.

            All my sailing boats have had one thing in common. Their engines never worked when needed. And when facing adversity you develop forgotten skills. I might be the best person on the planet in regards of safely sailing into a harbour. I have done it hundreds of times to the utter panic of every other boat owner who sees me coming on sail into their harbour, amicably aiming for their multi-million dollar yacht. Never even scratched anything while on sail.
            In many countries it is even illegal to sail into port… I just go: “Oh, well I will not do it again!”, and then do it the day after.

          • I a friend of mine bought this antique wooden boat. Tried to talk him out of it. Nice little 28′ gaff rigged schooner.Good shape too.Except that you did not let it dry out. he Hauled it
            out for the winter didn’t put in until June even with the wet climate of Oregon, He put it in and left it until the next day
            -when he came down to the dock and the boat was on the bottom. Just the masts sticking out…..He did salvage it.
            did a bit of restoration-and sold it…

        • dear geo,

          I do like how you can do crazy things in the USA. If I did that in the UIK I would be behind bars in a second.

        • Well, the traffic incidents were happenstance. As for being clear of any wrongdoing, blind luck was on my side. The pedestrian thing left me with her son trying to get his own justice for 2 weeks until he nearly flipped his truck chasing me. Seemed that I knew the back roads much better than he. I also knew exactly where that 89° corner was at and that a creek was just the other side of the bushes. (Caveat: I was 16-17 and stupid as can be) Did he make the corner? Dunno, don’t care. He left me alone after that. I was free to go on and royally screw up my personal life after that. (In a nutshell, I was an insensitive jerk) After that became manifest, I wound up in the military for 20+ years and am still kicking myself in the arse for being a jerk. Jim Beam can make the hurt go away. For a little while. But the past cannot change and your memory is your worst enemy. Sleep helps a lot, as does being a veritable “bad-ass” in your chosen profession. (Which can easily happen when your career consists of you eagerly trying to keep your mind occupied) Note: There is no solution in alcohol… though it is a solvent.

          With regards to the light, well, I did got chewed out by my station chief, but he had a lot more “less than stellar” Fire-Fighters to deal with than me. One reason I never went back to that station after I retired was that the then station chief had been a 15 year old punk when I last saw him and I had taken a knife away from him when he pulled it on me. In hindsight, that was probably not the best way to deal with it but I was much younger then and quite a bit more fit. Also, I was one of the only drivers cleared to drive our rescue squad. Not all of them could think “stick-shift.” {No, I don’t understand how that can be either. It’s a bit embarrassing}
          (≈11,000 lb chassis pushed by a Ford 7.5 L V-8. The motor had some serious torque. I think the county is still paying medical on the two Fire Fighters that got slung out the back by another driver enroute to a call) → The clutch was tight and 1st gear was a mofo. (Yes, I’ve seen it lift the front wheels on more than one occasion) In my opinion, this vehicle was only safe up to 85 mph. Anything above that and it tried to “float” the front wheels due to the huge drag of the box body mounted on it. (FHP had closed down the East bound lanes and I was ordered to get it to the state line as fast as possible for an extrication accident)

    • Reference GPS data. I have had two separate incidences with GPS auto navigation system that taught me to not fully rely on it. In Panama City, my GPS wanted me to drive down a quay to get to a maintenance site. Knowing that vehicles don’t float very well, I ignored it. On another occasion, GPS wanted me to drive through a corn field to get to a prison up in Graceville Florida. I went around it staying on the paved road.

    • Why are floating aids so mistrusted? They get run over a lot plus intense weather and seas can move them from their original position.

      My favorite buoy story. While transiting into or out of San Diego, one of our lookouts excitedly called down to Combat that “There’s a man on that boy!” {buoy}. He had spotted a sea lion taking a break and misinterpreted the dark skin of the sea lion as a wet suit.

      “Combat”; aka “Combat Information Center” or (CIC). Maintains a secondary navigation picture to back up what the bridge team is looking at. → During “restricted maneuvering” additional watch stations are manned to accumulate and record more detailed data

      • ” Maintains a secondary navigation picture to back up what the bridge team is looking at”
        Not necessarily always useful !
        But it allowed me to be hung on to my console when the bridge put us in the dry, because I knew where we were going to run aground…
        The only connection with volcanoes is that the Agung 50km away still laughs at them.
        (translated by DeepL.com)

      • Not necessarily always useful !

        Sort of depends on what you have for an OOD.

        My favorite OOD story is for an [intentionally unnamed] Lt who was desperately trying to carry out the Captains night orders. During most of the watch you could hear him calling back to combat for information about the ship we were supposed to rendezvous with. He wanted it’s location, but mistakenly only asked for it’s course and speed. CIC, knowing that our course and speed would put us in the needed position would only give him what he asked for. No elaboration about where exactly it was at. This particular officer was not well liked by the CIC crew and was quite amused as the stress level in his voice slowly climbed each time he asked. By the time it reached the point where he stated, :Combat, I can’t do my job if you don’t help me, what is the course and speed of the [ship name withheld to maintain anonymity], the CICWO relented and trotted out the bridge to straighten out what it was the OOD was after.

        BTW, this is the same guy that told us we were idiots since he and the rest of the bridge crew had visual confirmation that one of our active tracks was actually an island. (doing 12 kts and 20 minutes from CPA… also sporting a Decca series of Navigation radars) Turned out to be a coastal freighter masked by the sooty stack gasses wafting down to the water surface between us. Not dissimilar in appearance to the scores of other outlying tiny Japanese islands near the coast.

        Somehow during that time frame, I wound up with a kimono draped over one of my antennas…. and we had not even been in port yet. Sun comes up, I get called to the bridge and told to address the problem. So, I ran the men working aloft forms, put on my safety gear, climbed the stick and and went to talk to the kimono, but it just lay there. I pulled it down and tossed it into the trash. Wile I was aloft, most of the radars had to be offline, so Combat and the Bridge were effectively radar blind while I “adressed” the kimono problem. The OOD was mainly interested in having the Captain not see the slightly embarrassing kimono problem, but when the “Men Working Aloft” announcements started being put across the 1MC, the Captain was curious about what was going on, so he found out anyway. Turned out he was more concerned about the loss of radar functionality while I was aloft than the embarrassing kimono. {Only natural since “safety of the ship” is his guiding principle} … and, unless someone inside Japanese territorial waters launched a missile at us, that kimono was not a hazard.

        I still don’t have a clue how it got there. Unless someone in Japan had a really bad experience with a tornado, I can’t even hazard a guess.

        • The reason for the name and identity ommissions is that it is possible that said entity is still in active service. Based on typical rank progression, he would be somewhere at the Mid-Grade Admiral level by now… provided no one discovered or called him on his idiocy. But, most of my Captains were quite adept and insightful (including that particular one) so it’s unlikely that he could go very far without someone whose opinion REALLY mattered finding out.


          Same guy nearly shat himself when he asked me about a radar I was looking at during a FON Ops passage. “What’s that radar” → ‘A fire control radar’, “Oh, what’s it doing” → ‘Looking at us’. Que the panic.

          (I had already logged and reported it to CIC, so his darting out with this tidbit of tactical data to the TAO was a bit useless.)

          As for the radar, this particular model has a very distinct scan mode change when it switches to high resolution tracking mode for getting a target solution. It never did that, but that was why I was watching it.

          • I think one of my better Captains was a bonafide Parrothead (Jimmy Buffet Fan) and the one who had the greatest mastery of driving the Cruiser was a native of Dothan Alabama {i.e. pure redneck by birth, someone I can respect.} His maneuverability was better than a bass boat… and we pulled 8520 tons displacement and were 533 ft long. He had innate ship-driving skills. During one interdiction operation, after discovering that the engineers in Main Control were puking their guts out every time we were down wind of the ship with 300 dead sheep stacked in the corner, he stopped our slow circle of the target vessel, backed down then performed a twist maneuver and circled in the other direction moving upwind. You could have probably tossed a broom from our bow to the other vessel we were so close. (The dead sheep had allegedly died in transit and the were stacked in a corner until they could dispose of them.) {Not the worst smell, on the Seattle we picked up a floater outside of Jebel Ali under the idea that maybe the port authority would bring us in early since we had found a missing person. We were wrong. We stashed the body behind the wind break… the air intakes for the engineering spaces was directly aft of our body storage spot. They were not happy campers. Ambient temps down there are easily 120°F to start with. And the person in charge down there, the BTOW, had a fixed air duct directed right at his watch station.}

            Note: I have nothing against Snipes, they have a hard enough job as it is. My greatest problem up in combat was keeping the OSs away from my thermostat. 50°F tends to get on your nerves after a few hours, and I always kept my gear as cool as possible. If it were just an office, I’d have no problem with a warmer temperature setting, but I had a few thousand watts of electrical gear in there that accumulate heat very quickly unless you kept it chilly. I did however, let them shut the door to my equipment room. I think that my documented left ear hearing loss was in part due to the ventilation trunk fan in the space. (It could also be in part due to being on a radiotelephone circuit when the crypto drops sync. I used my left ear for that since I preferred my right ear to monitor radar signal tones.)

    • Our local supermarket routinely replaces bollards that cars’ sensors don’t notice…

      As for GPS, my wife & I used to holiday in Scottish Highlands. The local Mountain Rescue team had had to add a new ‘Cause’ category to their incident report form, ‘GPS induced’.

      Many examples, but best was walkers tackling Ben Nevis via the ‘Tourist Route’ trusting their GPS over common-sense. One stage, path follows a very narrow ridge, almost an arête. Nasty, convex scree to one side, precipice to other. Safe zone is often narrower than GPS fix errors. The ‘approach’ to arête certainly is…

      Now, if walker had invested in a Nevis map and compass, and used those correctly, they’d see the problem. Nah, they haul out even a high-end-Garmin and follow the wonky fix unto terror…
      🙁

      • Very fair points Nik!

        I usually do the old fashioned way: a compass, map and trusting my sense of orientation, and also being prepared is key (so I do not get nervous with things like fog, snowstorms and such). I also like to go with company (less risky then going alone) but that introduces the human conflict factor, which is when two or more humans disagree when to do in a situation.

        The truth is, I never got seriously lost up until now (neither with hiking in the Scottish highlands or in Iceland) Lucky me, yes, and I am generally a cautious person. I remember a few times getting in trouble with the weather in Iceland, namely sudden snowstorms and zero visibility. And I tested by luck when I hiked Hekla in 2012 and when I went near Holuhraun in the summer of 2015.

        Furthermore to make matters funnier, during Holuhraun, Iceland expanded a couple meters, so GPSs would show a slight deviation in maps. You would be better with a map than with a GPS!

        Nonetheless, a GPS can still be a life saver, if conditions get pretty bad.

        In conclusion, common sense is very important.

        • It depends where you are. In places in uk moorlands its pretty featureless and landmark-free. Then its really nice to have a gps fix of your co-ordinates on the map to know that you are here, and not here. Saved me many a tedious yomp over boggy moorland. In britains micro-scenery you move quickly from one spot to another, unlike the US and europe where typically you have the same view all day.

  11. This is leaving quite a false impression of LLSVP and superplume for the readers.
    Based on your description, the Pacific and Africa LLSVPs are almost like scale up mantle plumes just covering much larger area, but that is no longer the case. Some scientists used to interpret it like that, such as Thompson and Tackley back in 1998, but more evidence is showing that these two structures are completely distinct from mantle plumes, and they don’t make direct contact with surface, although the origins of plumes are closely associated to them.

    Recent geochemical and geophysical constraints suggest that LLSVPs are likely denser than the surrounding mantle and are not mantle upwellings (mantle plumes), although most of mantle plumes and ancient LIPs have roots near or at the margins of LLSVPs. LLSVPs themselves don’t seem to erupt but small plumes would rise to surface from their margins. There are several models to explain this observation.
    The best interpretations of these deep mantle structures are primitive material, subducted slabs, or mixed of both piled at the bottom, not mantle upwelings/mantle plumes.

    • As I said, this has been debated for about 2 decades now.

      There are indeed as you saw a limited number of scientists arguing your point. They are though in a minority today, even though they are very vocal.

      Since I do not want to forestall an upcoming article I will here just say two things. One, we do have petrochemical evidence of deep mantle origin.
      Second thing I would like to say is that for deep root mantle plumes they would by necessity have a higher density, and not a lower one. You of all people should know this.

      • The root has to be denser for the sake of stability. But for the parts of rising plume or superplume, it cannot be negatively buoyant. Some evidence argues for lower density of LLSVPs than surrounding mantle thus making them mantle upwellings (Koelemeijer et al., 2017) which lends support to LLSVP-superplume hypothesis.
        I see buoyancy as one of the central contentions regarding of LLVSPs. Most of evidence (Lau et al., 2017; Williams et al., 2019) argues for negative buoyancy which makes LLSVPs just stable piles made of primitive materials survived since magma ocean stage, and plumes derive from their edges through some physical processes.

  12. I was also reading your article on Cordón Caulle eruption and did a little research on my own. I find the VEI 5 claim does have solid support.
    Two other teams mapped their own isopach map and recalculated the tephra volume and obtained the same number. One of these scientists was Bonadonna who created Weibull method. These numbers are 1.1 +/- 0.2 and ~ 1 km3.
    See https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/2014JB011478 and https://www.nature.com/articles/srep17589

    The reason Pistolesi said VEI 4 is because he considered every phase of the eruption to be an individual event, but the total volume does make up to VEI 5. Although the main phase (A-F) is VEI 4, but a few smaller eruption later in time have volumes high enough to make the total > 1.

    Let me cite one statement from the paper led by Bonadonna:
    “Individual phases of the eruption range between VEIs 3 and 4, while the cumulative deposit related to 4–7 June 2011 is associated with VEIs 4 and 5 and a minimum magnitude of 4.8”

    • This was exactly my point.

      When you tally up the numbers of that specific paper, subtract the lava that is erroneously added in, you end up below the threshold for a VEI-5. As far as my memory goes Bonadonna debates it in a way that points to it to be a high-level VEI-4 at around 0.8km3 (the same as you are now stating).

      And now over to the Weibull distribution (distribution, not method). I have met Jörgen Weibull a few times when I was young, an incredibly impressive man. Let me here state that it was Weibull himself who came up with the idea of using the Weibull distribution in the sciences of history and archaeology, and not Bonadonna. Volcanology borrowed it from archaeology.

      Now, here is the fun part. It was not Jörgen Weibull who came up with the Weibull distribution, that honour goes to his relative Ernst Waloddi Weibull who presented it in 1939. In turn Jörgen Weibull got it via another relative Curt Weibull. Ernst Weibull was an oddity, to my knowledge is he the only Weibull (out of 10) to become a Professor and it not being in History. Talk about being the black sheep.

      Furthermore, if either of the Weibulls had red the paper I quoted for how the distribution of the sampling had been done, he would have ran that student out of the University… He had a massive pet peeve against cherry picking data.

      For those who do not know about Jörgen Weibull, he was one of the most stringent followers of the idea that even a single error in a fact would void the research until it was corrected. He took this into extremis when he aged 82 walked into his old alma mater and redacted his bachelors paper on the terms of having placed a single decimal comma wrong. He then continued with trying to have his doctorate degree revoked due to his education up to that point being based on that error.

      So, who was first using the Weibull distribution in volcanology? Thorarinson.

      I hope that you see my point now Costanza? (My guess is based on linguistics, am I correct?)

    • Now, let me requote your quote:
      “Individual phases of the eruption range between VEIs 3 and 4, while the cumulative deposit related to 4–7 June 2011 is associated with VEIs 4 and 5 and a minimum magnitude of 4.8”

      I omitted this entire line of reasoning in my article since it would have made for an incredibly short and boring article that would not be educative.

      PCC erupted in distinct phases, and this is problematic. The definition of the VEI-scale demands continuity. I overlooked this in my article too for the reason above, and also since the eruptive phases are so tightly temporally dispersed.

      If we would have talked about Etna and been using the nomenclature in Italy (that you clearly are familiar with) we would have ended up with a series of paroxysms counted as individual eruptions.

      To the best of my knowledge nobody has ever defined the minimum amount of time that has to go between paroxysms for them to count as a single eruption. Someone at INGV could probably answer if they have an internal delineator on this subject.

      So, in fact you just dug up a point where I was intentionally fibbing things to get a discussion going, and that would indeed have been a show-stopper. I have been waiting for someone to get to that. I just did not expect someone to try to use it as evidence for it being a VEI-5…

      • Any maximum length of a lull before it’s considered a separate eruptive episode is going to be arbitrary, so how about this instead: An eruptive episode begins with any eruption of fresh magma, and ends at the first subsequent time where both of the following are true. A) there is no magma being erupted by the volcano at that time, and B) its level of seismic unrest is not much elevated above its typical background level of seismicity during past extended intervals of dormancy.

        The idea being, it’s likely returned to a meta-stable dormant state if those conditions obtain, whereas a lull in magma erupting to the surface while seismicity remains elevated means it has not returned to such a state.

        Notably, these are the same criteria typically used to decide whether to lower an alert level yet.

        So, “separate eruption” requires “separate period of unrest”, with an interval (however brief, be it millennia or mere weeks) of apparent dormancy in between.

        This definition has the added property of coinciding with the old one in the case of Hekla. 🙂

        • HVO follows the GVP definition, which classifies the end of continuous volcanic activity based on an absence of eruptive activity over a 90 day (three month) period.

          Note that explosive volcanic activity may not involve (much) lava.

      • Indeed the definition is ambiguous when it comes to individual phases and eruptions. But if we do scale VEIs only with individual phases, a lot of super-eruptions (VEI 8) are much less in magnitude.

        Yellowstone HRT was once thought to be a single cooling unit, but field studies carried out by Wilson CJN in 2009 have shown that the three ignimbrite members are separated by years. I believe you have noted it while making the 25 eruptions list. Although member B itself is voluminous enough to be called a super-eruption, but whether it should be called a single eruption or the second phase of the eruption?

        Yellowstone LCT is a better example. Recent field studies have found time break between member A and B (CJN Wilson et al, 2018). If we consider them to be two separate eruptions, LCT would be VEIs 7 instead of VEI 8.

        Cerro Galan ignimbrites are also composed of multiple ignimbrite flows erupted over an interval of possibly 100 thousands of years (Kay et al., 2011) and certainly cannot be considered as a VEI 8 if we look its individual phases.

        Either way, I still take the total tephra volume of Cordón Caulle eruption as VEI 5 though arguable.

  13. Thank you Carl! Nice article indeed
    My friends visited Tanzania – Kenya last week.
    What will the next article be about?

    • Hi brother! fun to see you are curious too
      After all I learned you about Volcanocafe for over 5 years ago: finaly you pops up here 🙂

      The next VC article will probably be about Iceland
      Then more Africa articles are planned …
      If Im correct here.

      Thats my brother Johan August Sandberg

    • Welcome!

      It is a beautiful part of the world.
      Tomorrow evening there will be a new article, but I will leave the subject unknown for the sake of suspense.
      I will though return quite extensively to African volcanism in the not so distant future. And also there will be a bit of Grimsvötn soon due to your brother coming up with a good question. I am still inclined to forcing Jesper to do a ph.d. to answer his own question in his own thesis.

      • Yea it will be good
        Thanks to JS I have seen molten lava upclose
        thats an absoutley unreal sight : )

        JS is no odinary person: he have seen more volcanoes and eruptions than any other person in this country in HIS young age.

        He come from Sweden, but home is anywhere earth spews fire.

      • I do freely admit that Jesper has seen more volcanoes than I have done at this age.

      • Tomorrow evening there will be a new article

        Unfortunately, I can’t read it because your machine is serving up a stale cached copy of the site’s front page, which predates whenever it was last night that you uploaded the new article. 🙁

        I suppose I could still view it if I could guess the URL, but I don’t have the foggiest idea what the title is, so unless someone links to it or fixes the caching issue with the front page this doesn’t seem possible.

    • Nope, you’ve been in a medically induced coma for 20 years due to complications during a routine colonoscopy.

    • Stockade?
      “Ten years ago a crack commando unit was sent to prison by a military court for a crime they didn’t commit. These men promptly escaped from a maximum-security stockade to the Los Angeles underground. Today, still wanted by the government, they survive as soldiers of fortune. If you have a problem… if no one else can help… and if you can find them… maybe you can hire… The A-Team.”

  14. Too much for the senior citizen these days for another Tanzanian adventure. Vicarious pleasures though via Google Earth. Scrolling westward from Kilimanjaro and Meru, with a tack here and there, will reveal a feast of volcanoes and their associated geomorphology. The surface has been bubbling away for aeons.

  15. Great article! thank you Carl …thnx
    I been to Dar es Salaam two times: I remember looking down at Kilimanjaro from window seat.
    I have a question, can Kilimanjaro do something like Tambora or St helens in the future?
    Or is it completely dead as all papers say?

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