# Planetary bodies, Volcanism & Earthquakes

Photograph from NASA. Jupiters moon Io infront of the planet.

For the sake of argument

Every 3rd Thursday of the month, I have to go to an appointment. I get dressed and walk downstairs from my apartment and stand on the street corner. Usually, a large people mover called a bus shows up. I get on and pay my fare.

Am I to assume that whenever I go to the corner, a bus shows up just because I am there?

That would be preposterous. The bus will show up if I am there or not.
Likewise, Katla erupts about every 47 years. Depending on how you work the average. Eyjafjallajökull, erupts about every 540 years or so. Odds are, that when Eyjafjallajökull erupts, Katla has either just finished an eruptive phase, or is well on its way to have one.

It has been said that there are lies, damned lies, and statistics. One of the most dangerous aspects of statistics is when you are not being able to tell when the data is lying to you, and what truth (as told by the data) is the real truth.

It is real easy for your own data and methods to convince you of something that isn’t real. Sometimes you have to take a step back in order to do a “sniff test” to see if it really makes sense.

Is there a connection between Eyjafjallajökull and Katla? Well, the jury is still out on that. I myself have seen what may be a connective region in the quake patterns, but that doesn’t make it real. Chemically, the two magmas are different. Each carries its own signature of constituent elements.

Now… about astronomical bodies

Vectors are mental mathematical constructs. They allow you to add two or more forces together to see what the result would be if they were to both act on an object at the same time. For example, if two pool balls, each traveling in its own direction strike each other, what direction would they go after a collision?

You can dig into it by representing each pool ball with a mass, and a speed… together with a direction. The mass and speed would give you a value of kinetic energy, and with the direction of travel, you get a vector.

The math can get hairy and tedious, so I will just point you at the law of cosines and the law of sines. All I wanted to point out is that you can add vectors to find out what the result will be.

The Sun is the most massive body in the Solar system. At about 1.99 x10^30 kg, it dwarfs the next most massive body (Jupiter) by factor of about 1048.

Newton’s law of universal gravitation shows that if you multiply the masses of the two bodies, then divide that by the distance between them squared, and then multiply that result by the Gravitational Constant, you can obtain the attractive force between the two objects.

So… lets do that for some of the more significant masses that affect the Earth.

This is a logarithmic scale, used only because the forces have such a wide range.

Image by GeoLurking. Gravitational Force between Earth and various bodies. Click for bigger image.

On average, the Sun exerts 175 times the force than the Moon
Mercury, 0.00004 times the force than the Moon
Venus, 0.00232 times the force than the Moon
Mars, 0.00005 times the force than the Moon
Jupiter, 0.00528 times the force than the Moon
Saturn, 0.00059 times the force than the Moon

So… Whenever you see someone spouting an astronomical theory about the influences of the planets, remember just how much significance that the planets have in relation to each other.

All of those forces are vectors. They have a level of force, and a direction. Those that pull along the same direction are additive, those that pull in opposite directions are subtractive.

There are also another set of forces that are at work that contribute to this whole she-bang… that of inertia. The Earth travels at a speed of about 29.3 to 30.3 km/s.

The mass of the Earth times the velocity would be the inertia that the Earth has.   And that large value is mainly acted on by the 3.5711 x10^22 Newtons of force (towards the Sun) that bends the Earth into a mostly circular orbit.

Next, you have rotational inertia. In order to get really accurate with the effects you would have to account for that also.

And now the one caveat that most loons forget… all this is in real time with constantly changing angles.

That plot that I linked only shows the intensity of the various attractions over the next few months. Each one of those vectors pulls along a different axis.

Can it be calculated? Yeah,  but I am not touching it, nor am I even going to try.
Once you realize that Jupiter and the rest have about 0.00528 the effect of the Moon… well, now you are into the noise floor… brutally.

Best-o-luck seeing how that shows up in your seismic listing or your volcano eruption.

In a nutshell… it ain’t there.

GEOLURKING

## 204 thoughts on “Planetary bodies, Volcanism & Earthquakes”

1. Talla says:

This is so true … humans are hard-wired to look for patterns, when they find patterns they look for meaning. Sometimes there is no pattern and sometimes the pattern has no meaning.

2. Carl le Strange says:

Next time someone comes frollicking in filled with the urge to prove that Plutos ascension into the celestial temple of Nibiru will cause loonageddon, use this text on them.

• Tyler Mannison says:

“Loonageddon” lol. I love it! 🙂

• 😆 you’ve got a great way with words.

3. Carl le Strange says:

For those who are inclined to read Science Fiction like I am, you might have thought “where did I see that image before”?
It was used for Iain M. Banks breathtakingly innovative novel “The Algebraist”.
Due to the nature of the posts, and as a nerdy joke on the maths involved I fel that it was ridiculously fitting. I know, my sense of humor is really weird.
http://en.wikipedia.org/wiki/The_Algebraist

• Talla says:

I must read that one day! Actually when I saw the picture I was reminded of images of the Transit of Venus – the next one is on 4th April and then we’ll have to live at Dweller pace to see the next one 😀

4. purohueso745 says:

I don’t know if it can be seen at 500m, but there is a ‘lineal cloud’ going from somewhere around Bob to the south…, hope is just a weird shaped and located cloud, 😛

5. GeoLurking says:

I wish I hadn’t gotten chased off to dinner during the writing of that.

A clearer version of a sentence.

“The mass of the Earth times the velocity would be the inertia that the Earth has… that 3.5711 x10^22 Newtons of force is what bends that into a mostly circular orbit.”

Reads better when worded:

“The mass of the Earth times the velocity would be the inertia that the Earth has. And that large value is mainly acted on by the 3.5711 x10^22 Newtons of force (towards the Sun) that bends the Earth into a mostly circular orbit.”

• Carl le Strange says:

Changing it.

• Jack @ Finland says:

Lurking,

You wrote:

Newton’s law of universal gravitation shows that if you multiply the masses of the two bodies, then divide that by the distance between them, and then multiply that result by the Gravitational Constant, you can obtain the attractive force between the two objects.

but in reality it should be

Newton’s law of universal gravitation shows that if you multiply the masses of the two bodies, then divide that by the distance between them squared, and then multiply that result by the Gravitational Constant, you can obtain the attractive force between the two objects.

You can check it at http://en.wikipedia.org/wiki/Newton's_law_of_universal_gravitation

• GeoLurking says:

You are correct. It was about at this time that the wife was grabbing her stick to force me to go to supper.

My apologies.

• GeoLurking says:

BTW, the formula used the squared distance between the two bodies.

• Fanfoe63 says:

Don’t have seen that …
Certainly because you’re in Newton, and me in m/s2 !

• Carl le Strange says:

Actually it is my fault. Lurking asked me to check it… And I missed that one.
So it is I who should apologize. I will edit it as soon as I am home. Mea culpa, mea maxima culpa! (Hides head in the dustbin)

• Fanfoe63 says:

Pas de soucis, no problem, aita peapea !
The most interesting here is to read, learn and sometimes comment !

• Fanfoe63 says:

Your right Jack@Finland, and I think it may change the “gravitation force between earth and various bodies” : I thought that Moon effect was dooble than Sun !?
Anyway I’m sure of that for terrestrial tides which depends of your position on Earth and geometry between Earth, Moon and Sun.
(you know g=9,8 m/s2=980000000 µgals : Moon effect is, daily in tides, approximatively maximum 250 µgals and Sun 100 µgals)
Anyway nice post GeoLurking

• GeoLurking says:

Feel free to check my work. The Excel cell equations that I used.

For the Sun

=G*((B\$1*E)/(((B5*AU)*1000)^2))

G = Gravitational Constant = 6.67E-11 N
B\$1 = Solar Mass = 1.99E+30 kg
B5 = Solar Distance = 0.996112 AU (for this particular cell)
AU = 149597870.7

For the Moon

=G*((H\$1*E)/(((H5)*1000)^2))

G = Gravitational Constant = 6.67E-11 N
H\$1 = Lunar Mass = 7.35E+22 kg
H5 = Lunar Distance = 395634.424392 km (for this particular cell)

Distances are from Alcyone Ephemeris v4.0.0.114, ephemerides dumped to Excel spread sheet with masses added and formulas transposed.

• GeoLurking says:

In both cases, E = Earth Mass = 5.97E+24 kg

• Carl le Strange says:

The problem I did not spot in the proofreading is now fixed.

6. Edward Lane says:

I thought early on in the life of Bob Lurking did a bit on tidal influence and earth tides too – and the lack of any correlation between them and eruptions/quakes – can one of the dragons search the site for ‘earth tides’ which I seem to recall being mentioned in/near the post from lurking. That could/should probably get appended to this ‘no fun’ thread 🙂

• Carl le Strange says:

Earthtides are funny.
They do exist, and are quite easily spotted.
For some reason they show really well on the Búrfell strainmeter.
Do they have anything to do with eruption happening? Well, if anything actually has any effect on anything that would be the culprit.
But it seems to have no effect whatsoever on volcanoes, and as far as I know the effect on any quakes are within “noise” really.
So, there might be a few quakes that happen an hour or so earlier than they should have, or a really excitable volcano might start an eruption around that time. But, regardless. They would not even be the real trigger factor, and they sure as heck would not be the cause behind it since it is plate tectonics and volcanism that causes earthquakes and volcanoes. Cause and effect are curiously misunderstood things.

http://hraun.vedur.is/ja/hekla/thensla_burfell.html
(Normally it shows better than this, currently the curve is slightly wonked for some non tidal reason inside of Hekla)

• GeoLurking says:

I agree about the Earth Tides.

Way back in my first “hard core” look at the Sun-Moon-Earth gravity relationship, I was exploring the notion that Full and New Moon (being the fully additive and fully subtractive orientations of the three bodies) would show a signal in the incidence of quakes.

In my little simian brain, I could see a pattern. There was an uptick. But it’s not large and is easily lost in the noise. That was even after I backed out the “dwell time” of the Moon at each point along it’s orbit. Compensating for the length of time that the Moon sits at each point (in this case, the time it spent inside of each bin)

I’m sorry, I used a concept that not every one thinks about. Binning is taking a large quantity of data and sifting through it by placing it into individual digestible groups. Something that you can analyze without choking your computer or making your eyes glaze over. In my case, I made “bins” out of the orbital positions of the Moon, and tossed all the quakes that occurred during that orientation into groups for later analysis. (If I remember correctly, I used 1000 bins on the 27 years of quakes.)

Despite all of my beating on the data, I couldn’t make the signal poke up above the noise floor large enough to definitively say that there was something there. That was when I came to the realization that it had no predictive value.

Even if you can state that there may be a higher likelihood of a quake, you can not state where that would be at.

Why do I say that? Because if there was location determining data in the incidence of quake-moon relationship, there should be a spike (or nuanced signal) pointing at particular angular relationships with the Earth-Moon-Sun indexes quakes.

And of course, the standard caveat. “I am not a physicist, geologist, astronomer, gynecologist… yada yada yada…”

Just because I can’t find it doesn’t mean its not there… but at least I went out and looked… and remain unconvinced.

• Carl le Strange says:

Now begs the question Lurking… Have you ever plotted something that merrits the “I am not a gynecologist?” caveat? 🙂

Lovely comment on the earth-tides.

• LAKAT says:

Well, according to wiki ‘Paroxysyms have a role to play in ” gratification disorder” (.Will that do?)

I kid you not! ( Alan and GeoLoco will click on the link, no doubt.)

Here is the link:http://en.wikipedia.org/wiki/Paroxysmal_attack

• GeoLurking says:

Have you ever plotted something that merits the “I am not a gynecologist?” caveat?

Funny you should ask…

I guess it’s a new field… not specifically gynecology… more along the lines of structural analysis.

• Carl le Strange says:

@Lakat:
According to Wikipedia Boris should be able to cure Etna with Carbamazepine™. 🙂

• GeoLoco says:

Lakat,
You are stereotyping me. And Alan. And all the Randies. It’s à scandal.
But of course you are absolutely right with your assumption…

• Carl le Strange says:

Why did I ask… *ROFL*

You did a Fibbonacci analysize on the measurment of women compared to length of “I dare not even think about it”?
You just made my day! I sure needed it 🙂

• Alan C says:

LAKAT
You’ve put me off me before-dinner whisky mac!
Crap day too – some cappadocian mushroom brain has been trying to tell me flint aggregate is the same as granite and comes from the same quarry!!
UUURGH!

• GeoLoco says:

Holy Randy.
I feel with you!

7. morning all
just a quick check in before I disappear into the bowels of the 1940 US Census. Images were just released this morning and I have missing relatives to find! The timing was good, I just finished up most of the chores that have piling up because of Bob.
I’ll pop in when I need a break from the dead people…

• Hattie says:

Morning eswiva, good luck on the ancestor hunt.

• LAKAT says:

@ Carl

Well, if stain-remover can cure Bob, I see no reason why Etna’s paroxysms should not be able to be handled by an enormous dose of Carbamazopine!! TM (Chemical structure/analysis required for Alan and GeoLoco so they can consider its potential before offering up as a solution to Great Boris for consideration.).

@ All

Please excuse us but paroxysms are paroxysms it is just that we usually use the word in a geologic/volcanological context. Just as we should!
😉

• GeoLoco says:

And there she goes on paroxysming and staining me. What have I done to you to diserve that? Whaaaat??? 🙂

• LAKAT says:

@ GeoLoco

Nothing my friend.

You have reached The Inner Chamber where we can be as unkind as we like to one another as it is all in good fun!

🙂

• GeoLoco says:

Do you realize what you just wrote? Want to kill me? Yeah the inner chamber where… So hot baby… 🙂
Sorry folks. The price for long term, monogamic relations… Sometimes what made us survive between the dino’s toes “erupts”…

8. Michi says:

Weird clouds over Hekla right now, just thought its steam and smoke….
http://eldgos.mila.is/hekla/
Now i think there are only clouds

• Carl le Strange says:

I think I will do a post out of this one day 🙂

Well, Hekla does not smoke really. Well, yes it does do that almost all the time, but it will not start an eruption with a puff of smoke.
1. A few small quakes.
2. Wait about an hour.
3. Then the entire mountain rips open in hellfire and molten brimstone, lavabombs are hurled up to 40 kilometers away, a massive ash column rises within minutes up to between 15 and 35 kilometers. Think nuclear blast here, only larger and continous.

When Hekla goes, you will not ask yourself, what is that smoke-puff. Compared to the candy volcano of Etna Hekla is the real deal. It is not cute, it is a behemoth from the nightmare part of life. Open Monday to Friday with guided tours of the eruption. Ice-cream sold at convenient spots.

• Carl le Strange says:

Imagine that you hear a bit of distant rumble and roar. You go out with your cup of coffee in your hand. You see this:

(This is Grimsvötn, ask Irpsit and Islander about seeing that with the morning coffee)

• LAKAT says:

@ GeoLoco

Inner Circle for you. (Is that better?)

In the corner for me!

(Oh no …..please stop!!!)

; – )

• GeoLoco says:

We won’t get it “better” between you and me… At least not today.
3 time I peer in after having decided to only look some earthquake data up and sleep… Pure weakness tonight…

• Ursula says:

This should go to the Treasury, perhaps Spica could put it there?

Amazing fact: first earthquakes of this eruption were measured at at 4:32pm. The eruption column was first noticed at 5:05 and at 5:10 it reached 11.5km height. So, not two hours, but 38 min from first earthquake to fully blown eruption!!

• Spica says:

Done, I added the post to the archives yesterday and we have a NO FUN section in the archives sorted by topic now. But like many others i had a not-so-good day yesterday so i stayed quiet.

9. Hattie says:

On the Burfell chart the line goes from thick to thin at times. My best guess is that when the line is thin the strain is not as much as when it is thick. Please could somebody tell me if this is correct, or am I way out to lunch on this.
http://hraun.vedur.is/ja/hekla/thensla_burfell.html

• Carl le Strange says:

Basically you are right, in a way of seeing it. But in another you are not.
What causes the line to get thicker is that the “micromotions” in the mountain is getting larger. So, yes it is a sign of larger strain changes, but not exactly that the strain in total is up. The actual change in strain is shown as the red line moves up and down the chart. High up on the chart is high strain, and viceversa.

Hope this made it a little bit clearer. Otherwise keep hitting me with questions.

• Hattie says:

Thanks Carl, will have a coffee and digest the answer, my brain is still in wake up mode.

• Tyler Mannison says:

It’s about 16 kilometers from the summit.

(measured the distance from the epicenter to the mountain on GE)

• Carl le Strange says:

That must constitute as either the slowest ever quake-swarm, or the quakes are aftershocks from the 2M quake a few days ago.
Regardless, they are very interesting.

• GeoLoco says:

Mmmmh.

10. GeoLoco says:

Geolurking,
Merci.

11. Carl le Strange says:

Interesting…
There is fairly no wind at all in the area, and still the micromotions on all 3 of the working strainmeters are getting more energetic. This might be a sign of more rapid tension changes in the bedrock.
http://hraun.vedur.is/ja/strain/1sec/index.html

This combined with the up-component in most of the GPS:s around Hekla is kind of interesting.

• Christina says:

I’ve seen that 🙂 But what I’m really curious about is that it’s going quite fast down on (Hau) And quite fast up at (mjo). Whats that about?

• Carl le Strange says:

That is due to it for once being almost absolutly wind free in the area.

12. Sam says:

From a novices point of view, (and from reading a bit from Jon) that these quakes are possibly related to the SISZ?

• Carl le Strange says:

Hello Sam!

Yes, they are most assuredly related to the SIFZ (South Icelandic Fracture Zone). The SISZ is around the Hengill area. The SIFZ is the area where you have fractures from large earthquakes, it extends from Hengill to Haukadalur in the other end.
Here it is that it starts to be really complicated.
According to some sources the area is a part of a microplate, and that microplate is squeezed between the spreading that occurs in the western spread zone and the eastern spread zone (they are the same as the volcanic zones).
Here is when we get into a bit of interpretative differences. That microplate can take only so much squeezing before it does what plates do when squeesed, and that is to subside. And here to make it perfectly clear we are out into unproven territory. But before going there, Hekla has a form of magma associated with subsidation volcanoes (it is the only volcano on iceland that has that) according to Sturkell et al. How then does Hekla get lava associated with subsidation volcanoes then? Easiest answer is that it is an subsidation volcano, ie. that the microplate is sliding down at a point somewhere between Saurbaer and Haukadalur. The last part is my conjecture (conjecture means idea that is put up for testing). Nobody has though tested this up to date. Jón believe this is a big load of hork, I believe it have merrit for further testing.
So, in my opinion the activity we are seeing now is due to A) motion of the microplate and B) residual activity from the magma that moved from Hekla to the SWS, and now is moving back (this is a fact).

Who of us is correct? Time will tell (and a bit of research).

• Sam says:

Oh, thank you Carl! That definitely cleared that up, much appreciated! 😉

• GeoLoco says:

Plate collision usually leads to subsidence / overrunning of one plate seen from the other. But if you have no significant density difference, then it can just be a collision mushing stuff together. Hummer vs Lamborghini is not Hummer vs Hummer.
I think you have have an interesting view, but maybe the subsidence is not “total”. Stating your idea is hork – with what we know is waaaay to “easy”…

• Carl le Strange says:

Interesting concept with partial subsidence. You are on to something here.
This I will have to ruminate on for half a year or so 🙂

• GeoLoco says:

I should draw you what I mean. See it in my head, but I’m zero in drawing.
Month ago when you came out with subsidence on the fellow blog you “won my heart”. I never put things clearly “on paper”, but that “partial subsidence” paired with hot spot stuff and so on explains a lot of the observed. It got me quite pissed to see some simply calling it invalid because of predetermined ideas.
I don’t like to state too much when I can’t prove any expertise in a field. We keep it on a “friendly” level here. It would be good to have 2-3 hours sitting araund maps with the big cheeses is Icelandic volcanology and really start to “talk stone”. But I don’t intend to make myself a fool in the net between 2 diaper changings…
Just go on with your subsidence idea. Won’t be that easy to prove you wrong for those who would like to… 🙂

• GeoLoco says:

months… with s

• Carl le Strange says:

You would be surprised about how many big cheeses are between diaper changes 🙂

(You lucky… …) 🙂

• GeoLoco says:

I am lucky.
It’s so good, this feeling that you are ready to give your life for your family, without any hesitation. Gives the whole hork sense. Make kids. It’s madness to some extend, but it’s the last illusion that separates me from total nihilism. And as I say it I know how sad we are. If our only sense is to make sure mankind goes on, then the next generations are just here to make next generations? And that’s the essence of life?
Be good as good generates good. Sadly is right for the opposite too. Life is a nice story. Cooler with more protagonists. Altough too many make things complicated…
Geez, back to stones… 🙂
And back to making kids… (not me – I have done my part 😉 )

• GeoLoco says:

Altough, sorry, it would not be honest to say it’s only luck. A long term relationship, basis of a family, is fucking hard work after the first luck to have met someone sharing the basic idea.
I have heard so many telling their separation stories. And if I’m honest, none of the long term couples I know would still be together applied to the standards of many separated I know. Now don’t think I’m saying there are no reasons to separate or divorce. But some of us should come out of their dream world where they think we all just have to wait, sooner or later the PERFECT partner will come… None of us is perfect, so don’t ask for others to be what you cannot.
Yes, luck has to do with it. But consequence, humility, immense respect and FUCKING HARD WORK come with it. Making the big choices in life thinking of others more than of yourself. The perfect job, but abroad and this pisses your partner – my advice: a job is not worth the feelings of someone you love. Who is ready to follow me on this nowadays? Well all tell me you are, in real life I didn’t see much and was told a fool. Now they come and tell me how lucky I am to have my relationship. Not what they told me 12 years ago as I refused a golden job for staying with my future wife… Everything has it’s price, hasn’t it? 🙂

• When it comes to degassing and explosive eruptions, changing diapers is what you could call field work.

• GeoLurking says:

Ever play with a Yo-Yo when you were a kid?

I think they should be banned. Yo-Yo’s are evil.

I have been married going on about… 29 years. Right now I have a step-son, his adopted son, and a bona-fide grand son living in the house. Along with their collective three dogs… of varying makes and models. (and neurotic behaviors)

Much like a Yo-Yo, when the shit hits the fan, they are back into the house. Not that I can blame them, a load of crap like that I would wish on nobody but the the highest political office holder. (pick the nationality, your choice).

The dogs? Well, I’m a dog person to begin with. Dogs and I have always gotten along. If a dog gets uppity, it doesn’t take much to flip them over and pin them to the ground. A couple of events like that and the dog begins to understand who not to mess with. A dog should always adopt a Beta attitude around people. A word of caution though, if your dog acts like an Omega, you are mistreating it. Many packs have an Omega, they are the whipping boy. You can spot them as the ones that cower in fear all the time. Omegas generally have a very short life span, so if your dog is acting like an Omega, coax it out and spend some time with it. Make it feel accepted.

Now I’m trying to figure out why the hell am I talking about dogs. Eh… whatever.

• btw I am heavily into outlandish theories that might just be right. It’s what all this open science thing is all about.

re the silicic volcanism in Iceland I posed that question waaay back at Eriks and EKoh (who studied with Erik) thought it mostly came from fractionation which got my little brain wondering how much fractionation do you need to generate that much rhyolite and over what time scales? And why are we getting such long pooling of melt in an extremely active spreading center, why is it not all just erupting in basaltic fissures like the rest of Iceland?

Another theory I heard is that there are some rags of old subducted crust under Iceland that are rising with the assumed plume and feeding silicic volcanism.
But that paper by Foulger that Peter put up seems pretty convincing to me arguing that there is “no strong evidence either for or against a plume”.. what did you think of it? If Foulger is right, then we are lacking a mechanism for the ascent of this old crust, if it even exists.

• GeoLoco says:

Lurking,
I’m a dog-guy too. No need for a reason to talk about them. What I love about them – they give without thinking what they could take. One for the pack, the pack for one. They “scan” you and look at what you are, not what you play to be. Sets a lot of things back to zero level when you come home after a day of loosing time with hypocrites.
The dog we have now is a Jack Russell. Wanted to be reasonable, and not take a big beast with small kids. Geeeez, I have never seen such a steel-head like that one. I’m not the kind who needs to show what a man he is by submitting an animal. But here I got my lesson. That thing is nice andbig hearted, but so strong in character. I have never been challenged as much than by these 6.5 kg of pure muscles and nerves. Amazing. She pushes to be an equal partner, but I have to keep her beta and under my kids – so hard that I just hope she won’t end up omega.

• GeoLurking says:

Bruce, I agree with the shards of old crust pancake idea.

Is there a hotspot? Yes. There is also evidence that it does not have deep source. Hawaii has a deep source. Iceland… not according to the He ratio (if I remember correctly) This would mean a more shallow source, and to fit that…. recycling crust melting out and drifting up to feed the hotspot.

Hydrated rock tends to melt at a lower temperature, and though hot, Iceland’s magama isn’t real hot. At least not as hot as you would expect from a mantle plume.

• Carl le Strange says:

Regarding the mantleplumes depth.
Here is where it gets wonky.
Bárdarbunga and Askja show deep origin due to amount REM (Rare Earth Minerals), but not especially much according to UrTh (Uranium/Thorium). The rest are consistant with shallower origin.
So, what am I on about? Well the REM count at B and A are so high that a deep source is the only answer.
Has me thinking that the center of the plume is deep, but that the outer layers are consistently shallower. My five cents.

Back to Hekla, fractionization just do not cut it. It does the work for Eyjafjallajökull, but not for Hekla due to the differences. On this I am totally with Sturkell. Only problem is that Sturkell never goes into how subductive-type lava erupts there… Sniffle…

• Sam says:

Aah Christina, You just beat me too it! 😀

• Christina says:

😀

• GeoLoco says:

Yes, dear Sam, one has to be incredibly fast to “survive” in here.
Terrific.

• Ursula says:

Yes and look at these clouds in the foreground (screenshot from mila cam just now, click for full size):

13. Sam says:

Earthquake at Hekla has been upgraded:

Monday
02.04.2012 15:45:34 63.967 -19.996 8.0 km 1.6 99.0 15.0 km SE of Árnes

• GeoLoco says:

• GeoLoco says:

That was for Carlos.
No one of us will be forgotten only because he has duties.
Strength and honor.
Or whatever…

• Carl le Strange says:

IMO is sure fast on them.

Then we can scrap the aftershock-theory. This is a very slow quake-swarm.

• Sam says:

Has Hekla ever had an event this far from the caldera? Or is it, like you said, just magma moving back? 🙂

• Ursula says:

@Sam, scroll up to the menu, click on Treasury and archive by topic -> there you will find two posts on Hekla that Carl wrote a while back, which explain these things.

• henrilerevenant says:

Caldera?

• Carl le Strange says:

Nice catch 🙂
The central volcano is a good name for Hekla. Normaly central volcano is not so usable though. Come think about it, what is an uncentral volcano? Suburbial volcanism 😉

• Ursula says:

Peripheral vent?

• Ursula says:

Ehm, that was a reply to Carl’s question on what is an uncentral volcano…

• Tyler Mannison says:

I didn’t even know there was such thing as a slow earthquake swarm.

• Sam says:

You and me both Tyler!

• Carl le Strange says:

Neither did I… But in lack of a better term, I think that it is what is going on at Haukadalur. A very slow swarm at the same spot.

Scary idea, precursor quakes.

14. Luisport says:

April 2, 2012 – COLOMBIA – Central Colombia authorities closed the national “Los Nevados” park Sunday after an increase in seismic activity of the Nevado del Ruiz volcano. Meteorological authorities raised the alert level to orange in 17 municipalities in Tolima and Caldas departments while visitors are prohibited to enter the park in an area in four departments. The measures came at the beginning of the holy week in which usually some 20,000 tourists visit the nature reserve. An orange alert does not mean that an eruption is imminent. –Colombia Reports

15. Luisport says:

• Alan C says:

AAARGH!
Why does this B…..Y machine, when I save screen, save all the junk around the piccie Jokullsarlon and not the ……. picture I ……..want! 👿

• Ursula says:

Here Alan:

Click on picture to get a full sized version, then right click and save image as. 🙂

• Alan C says:

Ursula
What a star you are!! Thanks!!

• GeoLoco says:

How does that go? Just post the link to a picture like for a YouTube video?

• Ursula says:

No, you need to put some html code. Not sure Carl wants this as public info though. 🙂

• GeoLoco says:

Nono. Just asked to know if I missed something. But this for sure is a case where less is more…

16. Ursula says:

Question for Carl: was looking at this page
http://hraun.vedur.is/ja/vatnajokulsvoktun/english.html
and opened this map

and noticed that there are many GPS stations around a lake called Halslon, north of Vatnajokull. My question is, why? They are too far east for Askja, right? So what is there that needs such detailed monitoring?

• islander says:

Why Carl, I know a lot on this too – As did a lot of “bread and butter” work on this many years ago and also rather recently. They are for monitoring of the areas around Hálslón (lake) and its huge dam (in the Kárahjúkar Hydro-Electric dam complex) and the 20 – 30 km of tunnels leading to the Fljótsdalur Hydro-Electric plant (usually going by name of “Kárahnjúkavirkjun”).

17. Luisport says:

Magnitude mb 6.1
Region GUERRERO, MEXICO
Date time 2012-04-02 17:36:44.0 UTC
Location 16.59 N ; 98.31 W
Depth 10 km
Distances 274 km S Puebla (pop 1,392,099 ; local time 12:36:44.5 2012-04-02)
166 km SE Chilpancingo (pop 165,250 ; local time 12:36:44.5 2012-04-02)
15 km SE Ometepec (pop 17,801 ; local time 12:36:44.5 2012-04-02)

18. I do not know of someone posted ot before

first underwater video from diario el hierro and salvamar

there is some degassing

19. Termite says:

Is it my imagination but does that clip on youtube make that degassing look VERY shallow , definately not 80-90 metres, and its quita a large area too.

• Hi Termite and welcome by the way.
Yes that was some point I wanted to discuss. I am not a professional diver but there seems to be no lighting. I think once prof is over 50-60 meters it is dark….

• Correction from the diario el hierro, they say depth is between 100 and 150 m. and that the reddish tint comes for the lighting of the camera. We wonder, yesss, we wonder my precious -;)

• GeoLoco says:

Nice because it’s an underwater video of that area, but I can’t see anything interesting. It doesn’t give any clue for activity / rest, growth or whatever. No indications concerning depth. Too much light for 80 m? But what kind of cam was used? Where very precisely is that?
Nice, but pointless.

• just the fact that the camera was lowered and did not move too much shows that the area is pretty calm. There is some degassing but it does not sell to be very strong (for that area). Of course I would like too to have some more info, but we have to do with what we have

• GeoLoco says:

Of course.
As said, nice.

• André says:

don’t know how to place a photo here. But, you can see the cam they used to make the underwater video from around Bob by usong the link.

20. Carl le Strange says:

And this is how it is done.

• Carl le Strange says:

Hm…

• Carl le Strange says:
• Carl le Strange says:

Mysterious photo:

• GeoLoco says:

I don’t get the mystery. What shall one see or not see or think?

• henrilerevenant says:

It’s Nessie!

• Alan C says:

I don’t get it either!!

• Carl le Strange says:

It is Kerguelen from a sailing boat. With a whonking albatross to boot.

• GeoLoco says:

And the albatross is the mystery if I get it right?
You just wanted a reason to show the pic… 😉 And it is a nice picture, that’s for sure.

• henrilerevenant says:

Setting sun does have that effect.

• Sam says:

It seems to be disappearing now anyway.

• henrilerevenant says:

Btw, welcome to the world of “pitfalls while observing a webcam”! No doubt you’ll come across the meteorological phenomenon common on glaciers where dense clouds keep forming out of nowhere in a single spot which looks exactly like a new vent. Or the moon, just above the horizon but below the CCD camera’s line of vision, shining through wisps of cloud over a crater which makes it look exactly like lava fountaining. I think it’s safe to say all of us have “seen” things which aren’t there. I certainly have.

• Carl le Strange says:
21. Luisport says:

April 2, 2012

Science / predicting rift volcano eruptions
Scientists are close to predicting large volcanic eruptions, thanks to their plumbing system, an international team of scientists has found after working in Afar (Ethiopia) and Iceland – the only places where mid-ocean ridges appear above sea level. When analyzing these crusts, they found that magma travels through chambers. By studying the locations and behavior of the chambers; they can easily predict volcanic eruptions. Magma chambers work like plumbing systems, channeling pressurized magma through networks of underground “pipes”. http://earthquake-report.com/2011/12/31/worldwide-volcano-news/

• Inge B. says:

This seems to me not really scientifically correct. Where did eathquake report (no scientists working there) get the information? I can’t imagine that is should now be “eas(y) (to) predict volcanic eruptions”. Also a contradiction to their own text above: “Scientists are close to predicting large volcanic eruptions”.

• Inge B. says:

Meant “earthquake report” of course.

• Carl le Strange says:

Let me clear here.
There are absolutly no chambers in the rifting zones of Iceland. Nobody has ever found any such between the central volcanoes of Iceland. Saying anything like that is hogwash. Pretty much they are saying that the central volcanoes of Iceland and Ethiopia would be possible to predict a bit. Ehm… Duh…

• Carl le Strange says:

I think that judging by the date was an april fools joke.
Otherwise it is rather iffy…

22. islander says:

Hydro-Thermal “news”! At old Geysir in Haukadalur (BTW NOT same area as Haukadalur “hau” SIL site) there is another geysir by name of Strokkur. Yesterday it blew twice usual height (30 m instead of usual 15 m). This “hot area” is on outskirts of old shield volcano and some quakes have been observed there. I have seen some anyway in last few years.
Icelandic news item at mbl.is (needs on-line translator) http://www.mbl.is/frettir/innlent/2012/04/02/30_metra_strokur_ur_strokki/ Nearest SIL is http://hraun.vedur.is/ja/oroi/gyg.gif or Gygarholskot. Mila webcam at Geysir is broken, sorry.

• Christina says:

Could that have anything got to do with Hekla?

• islander says:

I think rather different system, but curious regarding this indicates more heat coming from below (or some other changes giving the same effect). But there is another news item today, about that lake in middle of ASKJA VOLCANO is now ICE-FREE in mid winter, and this is considered maybe due more thermal heating (and it needs lots of it as it is 220 m deep) – Similar happened before 1961 eruption, the article notes – Reporter even asks if eruption is coming? And get answer “no indications of that”. A survey plane (the Icelands Coast Guard´s DHC-8 TF-SIF of Eyjo fame) flew over with its heat-detecting FLIR camera but saw no “hotspots”. (Full article needs online translation). http://www.mbl.is/frettir/innlent/2012/04/02/oskjuvatn_islaust_med_ollu/

23. islander says:

*small old shield volcano cone

24. Judith says:

Another video of Bob.

• great Judith

Verrrry interesting, it is before the link I gave with the end of the vid the same.
Apparently we begin in one of the craters, then the we see some fumaroles and degassing. We loose the 1 mn of footing and see more degassing.

• what makes me wonder is that in fact we see 3 fumaroles, the biggest being on the right side. Then, we see the 3rd fumarole getting more violent and then…one minute time jump…also there is the question of the light.

• KarenZ says:

Thank you.

A lot of degassing but no vent. A pity the depth isn’t recorded properly. I am sure that the video is taken at a depth of less than 100m but maybe a tad more than 000m.

• KarenZ says:

Checked out visibility for diving at La Restinga under normal conditions; it is around 20 meters.

But it has just occurred to me – we see all that de-gassing but no ash (nor anything else) clouding the water.

• Hattie says:

Thanks Judith, I found the video really interesting. To me it sure looks shallower than 100 to 150

25. Ursula says:

I know it’s not Friday, but anyway, here are a few confused goggle searches of last week and respective answers :
– “dalek mailbox”
Does Dalek have a post adress? If so it’s either at the top of Burfell near Hekla or at the pier at La Restinga.
– “brits in turkey?”
I’m sure there are some, yes, probably lots of tourists.
– “volcano vaporizer for sale scotland”
That’s something that Alan may know about? 🙂
– “hiking hekla volcano alone”
Totally not advisable. Duuude, read the posts here (and the paper above), it may need as little as 38min from first tiny earthquake to eruption and 11.5km ash column!

26. GeoLoco says:

That was one weird day. Hope it ends in total happiness for all you magma blooded lavaholics.
BBGM.

• GeoLoco says:

BBGN. N of course.
Should really get some shleep…

• Hattie says:

Night night Geo, sleep tight.

27. Bobbi says:

Hello everyone. Back home after a couple of days near Chicago visiting family. I thought of all of you when my daughters took me for a lobster dinner and we had chocolate lava cookie for dessert. It was delicious. Now for a question. If Bob is at 70 meters from the surface, where is all the degassing in the new video at 100 – 150 meters coming from? Fractures?

• KarenZ says:

I would guess fumeroles and / or percolating through the rock (small holes / fractures).

• probably hot water percolating and getting heated and of course other gases (CO2, SO2, H2S), but as the bubbles seem quite clear I would guess CO2 and water vapour.

28. Judith says:

RTVC.es are saying that the red glows on the video are due to reflection of the camera ?

,,Also you can see the reliefs on the building and volcanic cone with many points of gas emission, and reddish tones that occur occasionally due to reflections in the camera lighting and particles effects of high temperatures on the elements of the camera, as reported by the Government of the Canary Islands in a statement.,,

29. Judith says:

The above post should have said RTVC.es are reporting that the Goverment of the Canary Islands are reporting the red glows are reflections in the camera.

30. Irpsit says:

Hekla is quiet, and you will never see anything on the webcam, until the eruption starts. I went to Hekla summit last summer. This is what you can expect: there is no caldera! there is no crater. There is only a 5km long crack on the ground along the mountain which is in fact alongated. Over the summit the ground is hot and steams a little. But you cannot see this steaming unless you have binoculars and you are at least 5km close to the volcano.

Hekla does have a pattern of not having earthquakes until 1-2 hours before the eruption. Because of this it does not give warning. The first warning sign is sulphur smell some hours before but that might go unnoticed, because there is not so many people living close to Hekla.

Now, most important: These recent earthquakes are not in Hekla and not related to it (as far as is known by Icelanders). These quakes are at the end of the South Iceland Seismic Zone, which is a flat lowland, between two volcanic belts (and spreading rifts). Árnes is actually a common spot for large earthquakes swarms, on the past (earthquakes up to 6.0 and very active swarms, when they do occur).

If Hekla erupts, you will see earthquakes about 1-2 hours before but right at Hekla, not some 15km to its southwest. These start as M1 or M2, but sometimes there are also some rare quakes up to M2.5 without an eruption following them!

However, as Carl suggests, I do think that Hekla is a subduction volcano, caused by the squeezing of this “intraplate”. Therefore, earthquakes happening near Árnes, might be a sign of extra tension and result in an eruption in Hekla some time after.

Often, historically, there has been, on several times, a large earthquake in the SISZ just a few months before or a few months after a Hekla eruption. Too often to be a coincidence. But I think this is due to the intraplate tension and rearrangement, not a direct link.

Lastly, the “if Hekla starts eruptins, you cannot run away” is a myth. I actually met an Icelander this week which was hiking Hekla in the nineties, and was hiking at the bottom of Hekla when Hekla suddently erupted! He managed to escape, and said it was a good spectacle. But I dont recommend that to anyone! I also hiked Hekla and decided to see how fast I could run down. It is a ash slope, so its easy to run down, it takes about 30-45 min to the jeep park. But before that you must walk an extra 30min between the summit and the start of the slope, which has many rough lava fields (you cannot run there!). And lava bombs might hit you of course. (Carl, usually Hekla does not throw lava bombs 40km away, at least that has not happened in last decades)

• Irpsit says:

However there has never been so much instrumentation since 2000 around Hekla. We will see all kinds of stuff because there is much more to follow.

It is in fact very interesting to see all those microo earthquakes at Hauk.

• Christina says:

Ok, so whatyou are saying is that Hekla will not erupt simply because of these small earthquakes happening a littlebit too far from Hekla.

Can I just come with a crazy if theory?

We all agree, as you sa too Irpsit, that there is a lot of tension, we know that there are microquakes, we know that there is something going on with the strain, that Carl pointed out erlier today, we know that the last eruption from Hekla happened in 2000, and we know that she is “overdue”. We also know that there has been som earthquakes inside Hekla during the last 6 months, we know that there has been earthquakes around Hekla the last week or so. We have been noticing a lot of wierd things.

So what if, just what if, she is trying to tell us something? That this is her way of warning us? Maybe we’ll get a bigger eruption? Maybe she is changing? Could it be that she’s expanding? I know she looks so big and proud, and quiet. But I can’t help shaking the feeling that there is something we’re either not seeing, or understanding.

• Christina says:

Does anyone know anything about the water around Hekla? Like lakes and rivers and things?

• KarenZ says:

Check out these maps:

• Irpsit says:

Christina, Hekla is not overdue. Volcanoes cannot be overdue.
Volcanoes have sometimes cyclical patterns of eruptions and then vary those periods between eruptions. Since setllement, Hekla has erupted roughly every 20-40 years, but sometimes sleeping much more, even 100-200 years. Hekla was sleeping almost 100 years when erupted in 1947, then it erupted every 20 or even 10 years, since then. It does not mean it has to erupt now. It can sleep maybe 5 years, or maybe longer. We simply do not know.

The same thing goes for every other volcano.

Humans like to see patterns and regularly. It helps them know when things are going to happen, but volcanoes are irregular by nature. We cannot even tell that a volcano will erupt just because is chamber is already full. Look, Katla and Hekla apparently have their fulled chambers and have not erupted yet. Hekla also has much more than just one chamber, it has more. We do not know how are all those chambers, if full or not.

Last summer, there was a day in late August that Hekla had an earthquake 2.5 right on its summit and nothing happened. In 2000 it erupted with less than that. So, even that rule of “earthquakes only before eruptions” does not apply always. Volcanoes are complex and difficult to predict.

Just to show you another example.
Katla. Katla has been showing considerable unrest since 1999, earthquakes, swarms, tremor, inflation, even floods, and so far, even with the IMO always warning on Katla, nothing has still happened. Not even after Eyjafjallajokull. The rule has been broken, again. Grimsvotn was showing much unrest in 2010, and then it erupted in 2011, but curiously it was very calm shortly before.

I think, and this is my personal theory, that the trigger for these volcanoes is deep magma.
It does not matter if magma moves at the top or the chamber is full. As far as the pressure is stable, they do not erupt. Unless, a flux of new magma from deep, it forces the pressure too high, and results in an eruption. I think this is what will happen for Katla and for Hekla (but in Hekla, we do not detect her deep earthquakes) Or do we?

Maybe these tiny earthquakes are those deep earthquakes after all… but so far that is just a theory

• GeoLurking says:

You want overdue? Jackson Volcano is overdue. So overdue that it could probably be considered flat out dead.

Jackson Volcano sits directly underneath Jackson Mississippi. It was eroded flat and 884 meters of sediment formed on top of it.

At a bit over 65 million years… I’d say that it has had an exceptional repose time.

• Carl le Strange says:

I totally agree with the deep magma thing. Because a volcanic eruption is pressure passing the threshold of what the rock ontop can contain. That pressure increase is caused by energy entering the system, and there is one basic form of energy that can enter a system, and that is heat. In this case heat caused by magma entering.
Hekla might have an additional factor, and that is being squeezed like a zit, but that is another thing completely.

• henrilerevenant says:

Do you remember those red cubes used to illustrate the respective sizes of large volcanic eruptions? The itsy-bitsy one representing St Helens, the slightly larger Pinatubo/Krakatoa and the huge one Huckleberry Ridge (Yellowstone). The same relationship applies to Bob, Etna and Hekla in ascending order. If and when Hekla erupts and if we are lucky, we might be treated to this
http://www.supertravel-iceland.com/gallery/?pid=10 or the one posted by Carl earlier https://volcanocafe.files.wordpress.com/2012/02/heklaaurora.jpg?w=640

PS. That video of Bob shows post-eruption activity as far as one can tell, no sign of any ongoing activity, just degassing and cooling down.

• GeoLurking says:

“…and was hiking at the bottom of Hekla when Hekla suddently…”

• Irpsit says:

otherwise the poor guy could not have lived to tell his story 😀

• Inge B. says:

I actually try to imagine someone hiking in a magma chamber … 😆

• Inge B. says:

Active magma chamber, of course.

Reminds me of Jules Vernes, A Journey to the Center of the Earth … Though there they were not actually hiking into the hot brew. :):

• Carl le Strange says:

Please note all that he was at the bottom of Hekla when she erupted… Big difference. Yes, the 40 kilometer stone was from the 1947 eruption. I gave a worst case scenario.
Only little thing I have to add to your write-up is that Hekla had a bit of shifting of the lavas in the direction of Haukadalur, that might actually have changed the conditions a bit.

• Inge B. says:

Didn’t he mean at the foot of the mountain?

• Inge B. says:

Because I – caveat: not being a native speaker in English – would understand it otherwise as: “at the bottom of Heklugjá eg. (the eruption fissure)” and then he would have been flying very high in case of an onsetting eruption at the same spot. 😯

31. dianabarnes says:

Good morning everyone.
You know, if Volcanoes and Earthquakes ran to a schedule, or were found to be triggered by something as regular as a planet or star, I am sure this blog would not exist, Well, not in this format.
If that happened watching volcanoes would be like train spotting, The Blogs and TV programmes, like Railway stations packed with people with their anoraks, pencils and notebooks and cameras.
There would be thousands of similar photos appearing in the media and personal scrap books.
Old faithful and other geysers perform on time and attract crowds who watch, gasp in wonder, photograph ,then leave. Another box of amazing sights that we can all pay to see if we are rich enough , ticked.
A time schedule would make saving lives and property much easier……..Someday scientists will find , and be able to measure the many factors that trigger eruptions and ‘quakes but until then………Here we are being reminded how small, insignificant and ineffectual each of us are but collectively we can work towards being constructive and conservative.
This is the end of my philosophical rumination for the morning…..

• dianabarnes says:

………and here is a motivational video for the human race……..It says it all……

• villdee says:

Thanks Diane

Now I feel really motivated to face a dreary wet day in Ireland.
Love reading all your posts and thank you for introducing me to TED. Thats why I am addicted to this blog, education and laughs- great combination.

• Carl le Strange says:

I like your philosophical ruminations in the morning.
I wish I had that kind of mental clarity early in the day.

• Inge B. says:

By the way, even Geysers like Strokkur in the other Haukadalur in Iceland, is not really always performing on time! Sometimes you wait for 10 minutes or more, and at other times, it is just producing a water jet in triple sequence within 5 minutes. 🙂

[audio src="http://commons.wikimedia.org/wiki/File:Strokkur_Geyser_Eruption.ogg" /]

32. Judith says:

1136494 03/04/2012 03:21:05 27.7786 -18.1030 14 0.7 4 W FRONTERA.IHI [+] info

1136501 03/04/2012 03:43:49 27.7823 -18.0640 0.5 4 NW FRONTERA.IHI [+] info

1136500 03/04/2012 03:44:58 27.7519 -18.0552 1.4 4 W FRONTERA.IHI [+] info

• interesting, quakes are back. The 2 last one are at 0 depth…

• Inge B. says:

Could it not also be that they just don’t know the depth? I think Carl or someone mentioned in an earlier thread, that there is sometimes set in 0 in this cases.

33. Hattie says:

Good morning Judith and Diana, well its bed time for me now, hope everyone waking up has a great day, and all of us night owls a good night. BBGN everyone.

• dianabarnes says:

Shleep well Hattie .
Good morning Judith….

34. Judith says:

Good Morning Judith and Good Evening Hattie

Sorry not been myself over the last couple of days my husband has had an accident with a circular saw on his big toe and we wont know if we can go on our holiday for two weeks.

The good news is the toe looks like its going to be saved so he is hobbling about on crutches at the moment.

You just never know whats around the corner of life !!!

• Carl le Strange says:

Hope his toe will get better.
Circular saws are nasty really. One slip and…
Hope that your second honeymoon will work out well in the end!

• Talla says:

Hi Judith! Sorry to hear about your husband’s accident – thank goodness it wasn’t worse! I hope he gets better in time for your holiday. (A virtual bouquet of flowers for you both). 🙂

• KarenZ says:

Sorry to hear about your husband’s accident. Hope he recovers soon.

• My very best wishes for his recovery

35. Termite says:

Hi Judith, sorry to hear about your husbands bad luck, lets hope it doesnt postpone your holiday for too long,make sure he doesnt have you running around for him as most of us men do at times like this.

• Carl le Strange says:

I have noticed that when women are sick you get to walk on foot in the middle of the night in a snowstorm to buy chocolate. I think this is one of the more gender-equal things in life. You just take care of the better half when they are ill, injured or otherwise hurting.
Those I have a problem with are those who do not do it.

• Bruce Stout says:

You mean you have a problem with women who are never sick?

• Carl le Strange says:

No, I have a problem with people who do not help others when they are sick… You know the sort of people who never helps others…

I would though be nervous if I ever found a woman who never get sick. Robot alert you know 🙂

• henrilerevenant says:

Dors Venabili, yes. But I rather like the idea y’know, some interesting fringe benefits. 😉

• Inge B. says:

I like men who drive through a 44 m/sec. storm to get a sick woman home. 🙂

36. Termite says:

What im trying to say is, us men when we are ill tend to make a fuss, as in man Flu etc, but when women are ill they just seem to take it in their stride and just get on with things.

37. New post is up, a bit on the Ice free Askja.