Quake Watch 2011

Some charts for you to steal and hid in a corner slavering over. Well OK not quite, but enjoy! Oh by the way this runs from December 2000 and is the rolling 12 month totals up to July 2011.

As you can probably tell it i one of those 'graphing days' today. I finally got caught up with the 1930 to 2011 data which I am sure I did once as I have a graph, but cannot find. So, here it is again 1930 to 2011 (end of July) Magnitude 6.5 and over earthquakes.

Data sources are the Centennial Catalogue from 1930 to 2001, and ANSS from 2001 onwards. This does NOT contain any data from the 7 day files and thus should be accurate. Just a reminder that the reason for using 6.5 is because that is the level which is consider valid back to 1930. I could use 5.5 but then I could only go back to the 60s.



1995 was the year with the highest number of large earthquakes, but dipped out in the energy stakes. The 1960s dominate energy release. Actually I should say 50s and 60s really.

Whilst the pretty pink trendline is up for numbers of earthquakes, let's be sensible here. We are actually talking about the average number of large earthquakes rising from about 40 per year to 45 or 46 per year. Not really anything to get too excited about.

The energy release this year is beaten into at least 4th place by, 1964, 1960 and 1957. It will remain to be seen but there is a possibility if the pattern repeats of a 9.5 around 2014 and maybe another 9 in 2018/2020 - but only if that pattern holds.

I still maintain that you will NOT see a mega quake (8.5+) during the remainder of this year and possibly through 2012.

See the jageddy bits? Them's cycles. Not like wot you get in Beijing. Actually the count of large earthquakes is up and down like the proverbial, but the energy is much smoother.

If we could accurately roll the pages back on 6.5+ quakes I believe you would see this long running cycle - the curve on which the ups and down sit - having been up around the 1900s and there is certainly evidence of this with the San Francisco quake. Then go back to Tejon 1857 another ~50 year peak? And further back to New Madrid also a ~50 year peak in the cycle? Even 1775 may fit into this. It is something I aim to study further. The cycle seems to be between ~40 to ~50 years.

Can't deny the stats PuterMan. However, I am old enough to remember incidents in nature, not just earthquakes, where nature throws us a 'curve ball'......and then the stats start getting revised. As I remember my statistics lecturer telling us, "at the end of the day, statistics can always prove your theory, just depends what angle you are coming from".
Personally I don't think EQ's are our collective problem at the moment. Doesn't matter too much whether we are getting 3,4,5,6,7,or 8's. Massive eathquakes have caught us on the hop with no warning. Volcanoes are our problem, and just like EQ's no ammount of statistics is going to say what, where and when. But then that's my view, and if I was a statitician I could prove it! I still love your posts and will still turn to you for your view on all things 'shaky'!
Got my purple hat on so I Love's ya and there's a lovely rainbow over your home right now, you grumpy old f**t!
Jane

reply to post by PuterMan


Great work on the graphs

When I seen the Mag 6.5 1930-2011 graph I thought hmmm that looks a bit different than my 7+ graph, there must have been a lot of quakes between 6.5 and 7 on those years that peak high.

So I superimposed my graph over yours to see whatsup



Now keep in mind I have only done 1948 through 1976 off the Centennial List so far, the rest is NOAA and IISEE data based.

As discussed before here those Mag 9 "Great" quakes really pump up the energy release

Why some years with 9's showing higher ER than others?
More aftershocks?
Did some of those have more significant aftershocks in the 6.5 to 7 range (that I have not processed)

Lets have a look at the years showing high energy release on your graph (blue bars)

9.0, 1952/11/4 16:58:, 52.75, 159.5, 45, o/s SE of Petropavlovsk, Kamchatka, USSR (Russia), noaa
7.0, 1952/11/29 8:25:, 53, 160, n/a, o/s E of Petropavlovsk, Kamchatka, USSR (Russia), iisee

dl.dropbox.com...
Just the one aftershock above 7

9.1, 1957/3/9 14:22:32.6, 51.556, -175.392, 30, Andreanof Is., Aleutians, Alaska, USA, ehb
7.2, 1957/3/11 14:55:26.14, 51.398, -178.424, 35, Andreanof Is., Aleutians, Alaska, USA, anss
7.1, 1957/3/12 11:45:0.25, 51.678, -176.627, 35, Andreanof Is., Aleutians, Alaska, USA, anss
7.3, 1957/3/14 14:47:51.8, 51.298, -176.644, 35, Andreanof Is., Aleutians, Alaska, USA, anss
7.2, 1957/3/16 2:34:19.08, 51.519, -178.765, 35, Andreanof Is., Aleutians, Alaska, USA, anss
7.0, 1957/6/13 10:40:43.57, 51.491, -175.138, 20.3, Andreanof Is., Aleutians, Alaska, USA, ehb

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"Great" quake with quite a few aftershocks above 7

8.2, 1960/5/21 10:2:57.7, -37.872, -73.243, 35, SW of Curanilahue, Bio Bio, Chile, ehb
7.3, 1960/5/22 10:32:49.66, -37.993, -73.341, 51, W of Contulmo, Bio Bio, Chile, ehb
7.9, 1960/5/22 18:56:4.03, -38.147, -72.984, 35, N of Capitan Pastene, Araucania, Chile, ehb
9.6, 1960/5/22 19:11:17.75, -39.5, -74.5, 35, o/s W of De Los Rios, Chile, ehb (location by noaa)
7.0, 1960/6/19 22:1:, -38, -73.5, , o/s SW of Canate, Bio Bio, Chile, dgfudc
7.3, 1960/6/20 2:1:13.91, -38.254, -73.283, 25, S of Lago Gueulieu, Bio Bio, Chile, ehb
7.1, 1960/6/20 12:59:46.04, -39.218, -73.331, 25, o/s W of Tolten, Araucania, Chile, ehb
7.1, 1960/8/13 14:14:59.31, -39.914, -74.689, 45.2, o/s W of De Los Rios, Chile, ehb
7.2, 1960/11/1 8:46:1.08, -38.379, -74.848, 35, o/s Araucania, Chile, ehb
7.2, 1960/12/2 9:10:43.44, -24.677, -70.089, 15, SE of Cerro Amazones, Antofagasta, Chile, ehb

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Both foreshocks and after shocks around the largest quake ever recorded, quite a number above 7

9.2, 1964/3/28 3:36:12.66, 61.017, -147.648, 6.6, Prince William Sound, Alaska, USA, ehb

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Major quake but no aftershocks above 7

8.0Ms, 1995/4/7 22:6:56.8, -15.199, -173.529, 21, Tofua Arc, Tonga/ Samoa, noaa
8.0Mw, 1995/7/30 5:11:23.6, -23.34, -70.294, 46, Antofagasta, Chile, noaa
8.0Mw, 1995/10/9 15:35:53.9, 19.055, -104.205, 33, El Colomo, Colima, Mexico, noaa

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3 mag 8's but nothing else stands out as to the reason for so much energy release

And the other two "Great" quakes I would have thought 2004 would have been higher ER but of course being at the end of 2004 need to look at 2005 for the aftershocks, not many really above 7 in the early part of 2005 either.

9.0Mw, 2004/12/26 0:58:53.4, 3.295, 95.982, 30, Simeulue, Indonesia, noaa
7.3Mw, 2004/12/26 4:21:28, 7.07, 92.99, 33, Nicobar Islands, India Region, emsc
7.2Me, 2005/1/1 6:25:44.8, 5.099, 92.304, 12, W of Aceh, Sumatra, Indonesia, usgs
8.7Mw, 2005/3/28 16:9:36.5, 2.085, 97.108, 30, Bangkaru Is, Nias, Indonesia, noaa
7.5Ms, 2005/7/24 15:42:6.2, 7.92, 92.19, 16, Nicobar islands, India, noaa

dl.dropbox.com...
dl.dropbox.com...

And this years "Great" quake seems to have a higher ER than the lists show, so there must have been quite a high proportion of Mag 6 aftershocks or 6's elsewhere?

7.2Mw, 2011/3/9 02:45:20.27, 38.424, 142.836, 32, o/s Honshu, Japan
9.0Mw, 2011/3/11 05:46:00, 38.322, 142.369, 24.4, Near the East Coast Of Honshu, Japan
7.8Ms, 2011/3/11 06:15:45.94, 36.126, 140.234, 30.2, Ibaraki, Honshu, Japan
7.3mb, 2011/3/11 06:25:00, 38.106, 144.553, 19.7, Off The East Coast Of Honshu, Japan
7.2Ms, 2011/4/7 12:32:41, 38.253, 141.64, 25.6, Near the East Coast of Honshu, Japan
7.0Mw, 2011/7/10 00:57:10.1, 38.04, 143.25, 34.9, Off the East coast of Honshu, Japan
all data usgs/neic

dl.dropbox.com...
Similar sequence of aftershocks to the 1957 Andreanof Is 9.1 but with a foreshock

reply to post by angelchemuel


I will come back to your post later, but in the meantime talking about volcanoes take a look at the Godabunga (Eyja/Katla) plot.



Also take a look at Jon Frimann's helicorder



I think it probably needs watching to see if it boils!!

ETA: ESK and SNB are also showing some signs of this activity. It is the rise in the 0.5 Hz that interestes me.

ESK


SNB


The plots are all (C)Icelandic Met Office

Some of this may just be wind as we have a depression between us in Ireland and them in Iceland



Image (c) The UK Met Office

reply to post by muzzy


The mag 6.0 you may recall from an earlier post I made are about 50% in Honshu and the rest world wide so yes Japan had a very much higher ratio of Mag 6 aftershocks.

You also have to remember that Chile @9.5 was 5.6 times stronger than Japan @9.0. That is quite a significant difference. In Terajoules

9 = 1,995,262
9.5 = 11,220,185

Makes a HUGE difference to the spike on the graph, Then bear in mind that the ONE SINGLE 9.5 was the same energy as 1000 mag 7.5 and you get some idea of the power of that quake.

Then just for fun consider the DIFFERENCE between Japan and Chile, 9,224,922 Terajoules - about the equivalent of 820 Mag 7.5 earthquakes.

reply to post by PuterMan

Yep those 9.6's are big alright, glad there aren't many of them ( in our lifetimes anyway)
I'll study that Japan csv file you sent me and try and understand the formula for energy release you use.

I must go back and put the mag type on my lists, I thought I did from the start of 1948, but obviously not, means adding a column to each years csv file.
I'll never finish it at this rate, keep seeing better ways to present the data.
Have started doing timeline graphs for each year rather than bar graphs showing how many in which month.
Only done 1964-1976 so far.

Found an interesting article from CalTech for you quake enthusiasts.

New data shows El Mayor–Cucapah earthquake was simple on surface, complicated at depth
The El Mayor–Cucapah earthquake happened along a system of faults that run from Southern California into Mexico, cutting through the Cucapah mountain range and across the Colorado River delta. This system of faults forms a portion of the plate boundary between the Pacific Plate and the North American Plate. Two main segments of the fault tilt downward steeply from the surface at opposing angles: the northwestern half angles downward beneath the Mexicali Valley, whereas the southeastern half angles away from the valley.

"Although the surface trace is nearly linear, we found that the event, which started with a smaller quake, happened mainly on two faults with opposite dipping directions," says Wei. In fact, the seismic rupture traveled through a relatively complicated set of preexisting faults that are dipping in various directions. "It was really surprising to see a straight fault trace that cuts through the Colorado delta and the rugged topography of the Sierra Cucapah as a result of this event," says Jean-Philippe Avouac, director of Caltech's Tectonics Observatory and principal investigator on the study.

Caltech

Originally posted by angelchemuel
reply to post by relocator

 

Thank you, but I cannot take credit, it is something that has been practiced for eons and something I have seen first hand sooooo many times that works. I must admit that Aromaz' post immediately reminded me of that scene from 2012 where the tibetan monk is striking the bell.
Sorry to be off post here guys but it makes a nice respite for a moment from all that is going on.
I understand that earlier this year some of the highest tibetan monks disappeared into a sacred cave in the area that Aromaz talks about. Some Russian scientists were allowed close by to record the noises that were coming from inside, that according to the monks the cave makes itself, and when it does they believe the earth is warning of an imminent earth event.....this was just before the Japanese quake. Here is the link, enjoy. PuterMan...you might like listening to this, also there is an intro with LISS charts etc and link I believe to sound charts.

www.youtube.com...

Rainbows
Jane

@angelchemuel;
Last post about this here. Maybe make a new thread?

This is no strange natural phenomena; just a normal annual ritual calling for peace and the return of the Dalai Lama. It is not the Earth talking to Humans; it is Humans talking to Gods.

Only selected monks go to those caves for isolation and prayer for peace and life on Earth once every year. It corresponds close to the Chinese New Year. There they do make a heck of a racket with gongs, bowls, shells, bells, et all. The sound on this recording is exactly just that - Brass and shell instruments by about 800 monks; this was not natural sound. Starting off with ringing the bowls, and drumming the gongs. Around 4 minutes the blowing (shells) instruments come in. Between 4 and 6 minutes you can very clearly hear the different instruments if you listen carefully. Around 06:20 the rimming of the bowls turns to percussion. At 7:20 the gongs fades out, rimming of bowls becomes predominant. At 7:40 you can hear the feathering on the gongs. At 10 min the gongs came in strong again... etc.

These sounds are said to be audible through the echo's of the mountain for more than 25 km from the caves. The gongs at Lhasa monastery can be heard all through the town and down valley for more than 15 km.

@Jane; I am amazed at the worldwide effect, use and widespread gain of knowledge about thise instruments. They are truly amazing. Yesterday I bought 4 bowls that dates to Ayutthaya era; brass with nickel and high content of silver and gold, pure 'ugly' handmade! Lovely sound that goes on . . . and on . . . and on.

Love and Singing Brass Bowls

EDIT:
Oh and the hollow Earth ringing; that is not because the earth is hollow.
It is because the Earth has mostly two minerals:
1) Silica = Quarts crystal
2) Iron = steel.

Both of these are used to make resonant vibrating sound;
1) Crystal bowls (or wine glases) and
2) Iron singing bowls i.e. Modern Nepal, India and Thailand.

The Iron/Nickel (Male) content (Meteorites) in brass bowls is what contributes to the duration of the vibration.
Gold & Silver (Female) contributes to actual tone and clarity - defined sharpness of wave.
Brass (Copper, Zink, Tin and others) - Egg; are the bonding.

I would love to hear the sound of a Steel & Crystal alloy!

Must be graph and table day

I was looking at the energy thingy and ended up liking Tons of TNT
Joules, Gigajoules and Petajoules are too confusing for most people, but blow up a kg or a ton of TNT and most people can relate to that

Anyway I thought while I was at it to check the Moon Phases for those "Great" quakes

The 1964 and 2004 quakes match with;
Both on a Full Moon
Both 14 days after a New Moon

1952, 1960 and 1964 quakes were either 5 or 6 days before Apogee ( the point of the Moons farthest excursion)

otherwise nothing else matches up




oh and the 1957 and the 2011 quakes do match up with;
Both 7 or 8 days after a New Moon
Both 7 or 8 days before a Full Moon


so you could say that the chances of a Mag 9 being;

On a Full Moon 33%
14 days after a New Moon 33%
5 or 6 days before Apogee 50%
7 or 8 days after a Full Moon 33%
7 or 8 days before a New Moon 33%

or a 50 - 66% chance they won't be

reply to post by Aromaz


So basically I was right, it was NOT the sound of the earth and had nothing what so ever to do with the Japan quake. It is basically a fraud being touted round the Internet. Not a fraud in itself, but a fraud as it is being portrayed.

Anyways, change of subject.

reply to post by angelchemuel

As I remember my statistics lecturer telling us, "at the end of the day, statistics can always prove your theory, just depends what angle you are coming from".

Or as mine said "There's lies, there's damned lies and then there's statistics" (quoting someone else I believe)

Volcanoes are our problem, and just like EQ's no amount of statistics is going to say what, where and when.

I completely agree that we cannot (yet?) pinpoint when an earthquake will fault or a volcano erupt BUT I also don't think you can dismiss the stats quite that easily.

Consider this. We agree that earthquakes are caused by stress that builds until the fault fractures? We do not have to agree on how or why this happens. Given that there is a (necessarily) slow movement of the earth over a period of time then we could expect that an approximate period of time would be required to build up pressure between each release. Obviously we don't know if the pressure is fully released so there is a variable there, but over all we could say the we might expect an earthquake in a given area because of it's historical seismicity.

The same applies to volcanoes. Again, the ebb and flow of magma has a cycle as exhibited by Icelandic volcanoes for example, so we can say we 'could' expect Grimsvotn to erupt again in about 2019/2020 (I don't actually think it has finished this session but that is by the by)

Whilst pretty inaccurate as a forecasting tool there definitely is a place for statistics in both seismology and vulcanology. (The original and proper way of spelling it.)

And another change of subject.

First I really hope you do not get upset by this muzzy as I know you are working hard on mag 7 quakes. This is not intended to usurp your work and I have not painstakingly searched out all the mag 7+ earthquakes as you have, just gone by the Centennial and ANSS.

For a more detailed look at the quakes year by year and decade on decade please visit Muzzy's Major World Earthquakes - mapped, graphed and listed blog.

I actually believe the 6.5 quakes are good as far back as 1910 but 7.0 upwards have been vetted. I wanted to split out the different bands and ended up just doing 7, 8 and 9.

What caught my eye was that I thought the number of mag 7 quakes seemed to dip around the time of the mag 9 quakes. I also wanted to show the mag 7 by themselves. We were gulping at 21 mag 7 quakes last year - but that is far from the highest. There were 31 in 1943 and 29 in 1910, and there is a 25 as well. Anyway I spend the whole of this evening doing this graph so I am posting it, even if only to make the effort worth while!!



The big mountains are the count of Mag 7. The small foothills are the count of Mag 8. I do not show a count of mag 9 as there is only one in any year they occur. The tall yellow skyscrapers are the mag 9 energy - each one a single quake, and the red and white buildings are the mag 8 and mag 7 energy levels.

I will add the cars and people later.

reply to post by muzzy


I was going to have a green free post but....oh well.

Nice work there muzzy. Not sure I can visualise 4 billion tons of TNT any better than 11 million terajoules. They are all staggering values!

So we got rid of solar flares and the moon. What is next?

Is the light blue shaded area in your graph reflecting human agression?
Spikes 1910, 1944, 1966, 2009/2010 - war.
Then 2011/2012 should reach new heights.

Just curiously interesting; nicely done Putterman!

I do agree the moon and sunspots are out.

Nice picture of Soputan tonight. Sorry I don't know how to put it straight on here

networkedblogs.com...

Rainbows
Jane

reply to post by PuterMan

Nice graph , I do appreciate how much work goes into these.
I do see the drop in mag 7's when there is a Mag 9

One question though, how come you have 2011 energy at a higher level when 1952, 2004 and 2011 were all the same, Mag 9.0?

When I was looking into joules and conversions I found this tool and its what I used for my table, but it must be noted that the conversion is based on ML, not on Mw or Ms.

So energy accuracy is not very good for these Mw's or Ms' Mag 9s.
You would have to go through the data and find the ML, which isn't always available.
FWIW NEIC have the 2011 Japan quake at 8.8ML which is 239,005,700 tons of TNT not 476,879,100 that I had in the table, quite a difference. There is no ML reading available for the Chile 9.6Mw ( magnitude taken from Catalog of worldwide earthquakes with Ms 7.0> 1900-1989 Pacheco and Sykes (1992))

It works OK for smaller NZ and Japan quakes though, as can be seen on Canterbury Quake Live

reply to post by Aromaz

Originally posted by Aromaz
I do agree the moon and sunspots are out.

edit on 13/8/2011 by Aromaz because: (no reason given)

I wouldn't completely discount them, just for "Great" quakes at this stage.
There really hasn't been enough of them to justify a conclusion.

Perhaps I'll have a look at "Major" quakes (Mag 8.0 to 8.9) and see whats showing there.
I have some time on my hands this week, its SNOWING

reply to post by muzzy


It seems that Japan has been lifted to a 9.1 in the ANSS database, which I had not noticed.

Date Time Lat Lon Depth Mag Magt Nst Gap Clo RMS SRC Event ID
----------------------------------------------------------------------------------------------
2004/12/26 00:58:53.45 3.2950 95.9820 30.00 9.00 Mw 601 1.17 NEI 200412264001
2011/03/11 05:46:24.12 38.2970 142.3730 29.00 9.10 Mw 541 1.16 NEI 201103112012

Source

ANSS however does not have 1952 as a 9, or an 8, or a 7 - in fact it just does not have it.

Date Time Lat Lon Depth Mag Magt Nst Gap Clo RMS SRC Event ID
----------------------------------------------------------------------------------------------
1951/02/13 22:12:57.00 56.0000 -156.0000 25.00 7.10 ML 0 AK
1952/07/21 11:52:14.54 34.9582 -118.9980 6.00 7.50 Mw 12 0.39 CI 3319401
1953/01/05 07:48:20.00 53.0000 171.5000 0.00 7.10 ML 0 AK

It is also recorded as a 9.1 Mw in the NOAA Earthquake Database. Since ML is not accurate at these levels I assume that we should actually now be using 9.1 ??

There is no ML reading available for the Chile 9.6Mw

First I thought this was 9.5 Mw not 9.6? I can find an Ms value of 8.3 but that is all.

The calculation I use is the one that site uses. =(10^(4.8+(Magnitude*1.5))) and /10^12 to get to Terajoules. I realise that there may be differences because some are Mw and some are ML and some are Ms and most of it is Bs.

I guess that swings and roundabouts it will even out, and if all the higher ones are Mw then it really does not matter what the unit actually is as long as the ratio between them is constant, for example the following is just as valid as a comparison and is simply 10^Mag = Energy Units, without specifying what they actually are.

Mag Energy Units
9.1 1,258,925,412
9.0 1,000,000,000
8.9 794,328,235
8.8 630,957,344
8.7 501,187,234
8.6 398,107,171
8.5 316,227,766
8.4 251,188,643
8.3 199,526,231
8.2 158,489,319
8.1 125,892,541
8 100,000,000
7.9 79,432,823
7.8 63,095,734
7.7 50,118,723
7.6 39,810,717
7.5 31,622,777
7.4 25,118,864
7.3 19,952,623
7.2 15,848,932
7.1 12,589,254
7 10,000,000

I guess all we are trying to convey is the enormity of the larger quakes.

I have tried to get my head round this moment of magnitude scale but decided in the end that since the Mo, Ms, Mb and Es scales are all rigged to approximate Richter magnitude then the equation above was good enough for most purposes. After all they can't even agree on the magnitude so what does a few joules, ergs, dynes or tons of TNT matter at the end of the day?

reply to post by PuterMan


The 1952 quake should show 9.0 on the Centennial List page 15 on the pdf version, (page 679 hard copy), third to last entry on the page.
screenshot

I agree that as long as the ratio is consitant then it should all work out, but thats the trouble, there are a lot of years when Mw wasn't used, a few years when Me was the prefered magnitude type and also MS isn't always available either.
If you only do Mw then its likely the number counts will be down at a lower level.

xyz energy units makes quite good sense.

reply to post by PuterMan

quote
"y PuterMan because: Added 9.1 to show the difference. Bear in mind however that this calculation only gives 100 x difference whereas the difference between a 2 magnitudes gap is actually 1000 times but since this is in small print and no one ever reads the small print it will probably not be noticed. Anyone who does notice will have to pay me $1000 in cash as a penalty for daring to read the small print, or for being a clever clogs. There gave you a reson box. Happy now?"
unquote

sorry im broke
like everyone else

reply to post by muzzy


By the time you get through this lot your eyes will be crossed.

Converting Earthquake values to Mw scale

Basically the Mw scale is a direct measure of the energy of a quake in dyne centimetres. I think that is something to do with the amount of work it takes to move a centimetre which is considerable at this time in the morning and before the first coffee.

There are various formulalas in there for converting stuff, but the crux of the matter is that unless you actually have the seismo data you are stymied. ML is useless above mag 7 and the best nearest equivalent of Mw is the Ms scale if you can get it.

reply to post by BobAthome


Well done Sir! Collect $0 and take a Get Out of Jail Free card that will fail when you try to use it.

reply to post by PuterMan


nice page you have built there.

yep gave me a headache alright

I tried a formula off the www.africaarray.psu.edu...
link, page which looked simple enough
Mb= 1.7 +0.8 ML –0.01ML2

Which I put in Excel format for a 4.7ML event as

=SUM(1.7+0.8*4.7)-(0.01*4.7)*(0.01*4.7)
Answer is 5.477mb

then I had a look at a USGS 4.7ML quake today off the recent Quakes page that had both ML and mb at the top of the phase data page and the answer they had is different 5.2mb
The there is another quake on the list that has 5.2ML but they have as 4.7mb, The conversion is reversed

Maybe you were right in an earlier post, perhaps they should just call the magnitude of a quake "Bs", its as good as anything else

Still don't know what the usgs "GS" stands for , could it be "Guess"

Thanks for that page though , picked up about 4 Afghanistan quakes background information that I didn't have anthing on before, to put on my maps popup tags. (had the quakes but no backgrond info)

reply to post by PuterMan


Forgive me but I am very tired tonight, but there is one thing that you said which made me smile and wanted to reply ASAP.
"Whilst pretty inaccurate as a forecasting tool there definitely is a place for statistics in both seismology and vulcanology. (The original and proper way of spelling it.) "

I always thought it was vulcanology, but until I got back into one of my favourite subjects (some 25 years!) and found people writing volcanology, I thought 1. I had it wrong all those years ago?....Nah. 2. like many things they have changed the spelling of it?....Oh, OK. So I take it VOlcanology will distinguish between 'old' school and the 'new'?

Rainbows
Jane