Quake Watch 2012

Regulars are well aware of the discrepancy between networks, not just magnitude but even location.
So how much?
Here I have taken the data from GFZ, EMSC, RAS and LDEO and mapped out each one for the period 2012/5/4 10:55:36 + 31 days.
The reason for starting 2012/5/4 10:55:36 is that is when I started saving LDEO data.
Also to be fair the lowest magnitude LDEO have in their data is 4.6, so that is the cut off point for the other networks as well.
The maps below will differ from the individual Page maps for each network on my eqarchives, due to the date and magnitude settings i.e. the Russian May Map starts 2012/5/1 and ends 2012/5/31 and the lowest magnitude is 3.4mb.

The Gif animation below shows how much the locations vary, and how some quakes are missed totally by some networks

you can see the individual interactive maps that make up the Gif here....
One that caught my eye was a rare moderate sized quake in the Tasman Sea between AU and NZ, 27/05/2012, not posted by USGS, and I note none of them caught that 5.0 off the East Coast of Oamaru SI, NZ that Geonet listed, not even an attempt at a sub 5 recording

Date/Time (UTC): 27/05/2012 9:27:09
Lat: -40.67 Long: 155.87
Magnitude: 4.9mb
Location: SOUTHEAST OF AUSTRALIA
Catalog Source: European-Mediterranean Seismological Centre

Date/Time (UTC): 27/05/2012 9:27:11
Lat: -40.65 Long: 155.86
Magnitude: 5.1
Location: Southeast of Australia
Catalog Source: GFZ German Research Centre for Geosciences

Date/Time (UTC): 27/05/2012 9:27:10
Lat: -40.72 Long: 155.64
Magnitude: 5mb 3 stations
Depth: 10
Location: Southeast of Australia
Catalog Source: Russian Academy of Sciences, Geophysical Survey

LDEO seem good at Pacific Ocean quakes, not so hot on SE Asia.

My estimate was 5.9, first reaction, with a leaning towards the minus side.

The wavelength period of S-Waves on spectro from surrounding stations is something I've been paying attention to, but not really mentioned. Just another tool in the box, so to speak. But it does tell us something. Quakes bigger than 6+ have a certain thickness to them as displayed on spectro. These were a bit thinner (shorter period).

reply to post by TrueAmerican

My estimate was 5.9, first reaction, with a leaning towards the minus side.

No you said rocked by a 6+

Towing the company line because USG have it on the low side? If your reaction was 5.9 leaning towards the minus side why did you not say so, and what are you now going to say when USGS put it up to 6.1. Mw, which they will and possibly even to 6.2 Mw. Take a look at the phase data. 6.1 mb which is 6.2 Mw.

They produce this stuff but it takes them a few hours to actually look at it.

Quakes bigger than 6+ have a certain thickness to them as displayed on spectro. These were a bit thinner (shorter period).

Come on TA you are waffling and not very convincingly. Here is the BHZ. That ain't a 5.8

MAJO.IU.00.BHZ.2012.157



Just in SCARDEC analysis Magnitude 6.3 Mw

Originally posted by PuterMan
reply to post by TrueAmerican

 

My estimate was 5.9, first reaction, with a leaning towards the minus side.

No you said rocked by a 6+

Towing the company line because USG have it on the low side? If your reaction was 5.9 leaning towards the minus side why did you not say so, and what are you now going to say when USGS put it up to 6.1. Mw, which they will and possibly even to 6.2 Mw. Take a look at the phase data. 6.1 mb which is 6.2 Mw.

I put it at 6+ because I saw it first on real time, thought 5.9, but JMA came up with 6.3 within a few minutes of the quake, so I just decided post 6+ so that readers would get a general idea of the size of the quake, before the USGS posted it, and while we waited. I didn't mention to the minus side because this time I just wanted to report the quake. Sheesh!

Towing the company line...WTF. :shk: No chance in hell of that, PM.

I want some of whatever it is you're drinking. Cause that accusation is getting old. And it's flat out wrong. I tow no one's line, and observe for myself. But I will be sure next time to take ten pages and explain every little bit of thought process next time I see a decent size quake. Just for you, sweetie. WOOF!

According to Prof. Nikolay Miloshev, Director of the Geophysics Institute at the Bulgarian Academy of Sciences, the blasts near Sliven caused an earthquake with a magnitude of 1.5 on the Richter Scale.

add it too your blast freq. sigs.
ohh Bulgaria,,
not a earthquake,,repeat not an earthquake.
used for seismic blast frequency,,recognition.

thnks

That Honshu 6'ish hasn't arrived at SNZO yet so can't say for sure. The SNZO seismo is playing up again, should I drive down to Karori and give it a kick with my boot?

For reference this is what a Honshu 6.1 looks like
and a Honshu 6.0
and a Honshu 5.7
Time will tell

Later

reply to post by TrueAmerican

I want some of whatever it is you're drinking. Cause that accusation is getting old. And it's flat out wrong. I tow no one's line, and observe for myself. But I will be sure next time to take ten pages and explain every little bit of thought process next time I see a decent size quake. Just for you, sweetie. WOOF!

Now now TA, ye have to have yer leg pulled. Don't take it so personally. If Eric can accuse me of working for the CIA I am sure I can accuse you of 'towing the company line'. It is what is called a joke. Oh by the way, I do usually give me reasoning so I look forward to hearing yours WOOF WOOF.

So really the question should be why is USGS getting worse and worse. This never used to happen.

New computers? Employing monkeys? I don't know but they are losing all credibility as an earthquake service.


Any minute now USGS will change that to a 6.1

earthquake.usgs.gov...

Originally posted by PuterMan
So really the question should be why is USGS getting worse and worse. This never used to happen.

New computers? Employing monkeys? I don't know but they are losing all credibility as an earthquake service.

Just keep in mind that if scientists program computers to do more accurate work than they do, they are going to program themselves right out of a job. I'd say budget cuts over the long term have probably forced more work towards the computers on the front end, with fewer people available to do the grunt work. So they set it up so that "we'll give you automated software that is good enough to get an idea of the magnitude, but it will always take us to review it for the final magnitude." Some savvy scientist is probably withholding the code right now for the ultimate autolocate/magnitude program- when he realized that would result in his termination, along with hundreds of his peers and friends. Those very people now working the review-after-computer-generated-message shift, and doing other similar things.

And in such a pursuit, they probably prefer to err on the side of caution and have the program guess high- which is why we usually see the quakes go DOWN in magnitude after the initial report.

Conjecture. That's what I do.

reply to post by TrueAmerican

reply to post by BobAthome

1.5 ? just a toddler

hey they did the same in Christchurch last year, to test the soil under the damaged Stadium, the blast came out at 4.2ML
where they got 30 tonnes of TNT from ................... ?

The stadium is to be demolished BTW

reply to post by TrueAmerican


Whill we wait for them to up it to 6.1 having read this thread and discovered what magnitude it should be ...

So they set it up so that "we'll give you automated software that is good enough to get an idea of the magnitude, but it will always take us to review it for the final magnitude.

I would go along with you on that but for one thing.



We now have a second, body wave tensor, at 6.1

earthquake.usgs.gov...

Any second now...........

No wait. Centroid 6.0 just in

earthquake.usgs.gov...

They may go for that - less scary being 200km from Fukushima.


Still no change. Right now telephone calls are being made........

Hello. EMSC? Listen that was a bit close to you know where. Could you drop it to 5.9?

Bon Soir USGS, mais Oui, but GeoAzur - zey hav eet at 6.3 and zay are good French peoples like us.

Hello. GFZ? We know you pride yourselves on Teutonic efficiency but we have to get this down below 6 or the 'OMG Pool 4' crowd are going to be going spare.

Guten Tag USGS. Ja, but now our friends the Russians have it as 6.2 Ms and 6.2 mb so vot can ve do?

Darn it, we need some more monkeys. These ones have messed up. We are going to have to put this out at 6.0 but there is one problem, we have read the ATS thread and they have pegged it at 6.1 or 6.2 and we know they always get it right.............................


They are working on it. Frantic phone calls still going on. Still no change but Potsdam have come down to 6.0, this despite the fact that their 6.1 was confirmed.



LDEO just in (22:54 UTC)

2012 6 5 19 31 44.0 35.25 141.25 33.0 6.2 NEAR EAST COAST OF HONSHU, JAPAN

www.ldeo.columbia.edu...

That Honshu is coming on SNZO now
yep looks like a 6.1 to me
link
same size signature as the one on 24/11/2011

definitely bigger than the 5.8 usgs have

thnks guys ,,, A-1 job.
its a rapid movement that sometimes can be positive ,,we all hope.

M5.9 - 71km E of Mutsu, Japan - down from 6.0

M6.0 - Western Indian-Antarctic Ridge - up from 5.9

Originally posted by muzzy
reply to post by BobAthome

 

1.5 ? just a toddler

hey they did the same in Christchurch last year, to test the soil under the damaged Stadium, the blast came out at 4.2ML

where they got 30 tonnes of TNT from ................... ?

The stadium is to be demolished BTW

After 30 tonnes of TNT I would expect the stadium to have to be demolished.

Well, that is what you wrote

P

Noticing what appears to be an uptick of sizable quakes in the Taiwan region lately, including a just reported M5.7 about 30min's ago. Just wondering if these could be fore-shocks to something bigger about to happen, given Taiwan's history of large quakes?

Taiwan has had and will continue to have many strong earthquakes. During the twentieth century more than 20 earthquakes have resulted in human deaths, and during a 45-year period starting in 1906 faulting ruptured the ground surface at six places. Taiwan is thus a place where earthquakes and faulting should be studied to minimize death and destruction, and where knowledge about these geologic processes can be gained for general application throughout the world.

A large and damaging M7.6 earthquake occurred in the northwest region of Taiwan at 17:47 GMT on September 20, 1999 (01:47 AM on September 21 Taiwan Time). Preliminary location is in Nantou County The epicenter was near the small country town of Chichi.

Casualties, collapsed buildings, and other damage were reported in the densely populated capital city of Taipei. Taiwanese television is reporting 2100 deaths with 8000 people injured.

Might be due again...

reply to post by SpaceJockey1

Yep they get some whoppers there
1951 there where 2 1 x Mag 8.3's + 4 Mag 7's
and in 1972 there where 5 x mag 7's

They haven't had a Mag 7 in the area since Dec 2006 when they had 2 on the same day

* links are interactive G Maps

I hear you've got snow down there in ChCh




FWIW heres a file I lifted off iisee Utsu, tweeked a bit with my own icons
Taiwan (Formosa) Historical Quakes 1604-2002 Mag 7+


Interesting, those 2 x8's I mentioned in 1951 may be the same quake, the one off shore at 2:47:local I cross referenced with Pasadena, but the other one on land near Yuli at 2:50:local was straight off Utsu, with the 8.3Ms value coming from the Remarks, which don't show on the Utsu KML file tags, it said "China:Taiwan(Ms possibly combined with the above) 8.3S" the above being the one offshore at 2:47:local.
Its showing now on the KML as 7.3

confusing

You can see why its taking me so long to build the MWE Project, every time you come across something like that it delays progress researching it to see if its a duplicate.

Theres a bit of a write up on Wiki about them 1951 East Rift Valley earthquakes

yeah looks like its a duplicate, I'll go and delete the offshore one

Its gone now! deletd from the 1951 file.
As you were

reply to post by muzzy


Thanks or all that info Muzzy.

Yeah, been snowing all day...complete whiteout here!

Interesting that last year we had two severe snowfalls, and preceding that 1992 was the one most of us remember as the BIG SNOW. Further snowstorms hit the region in 1996, 2002 and 2006. South Canterbury was the area worst affected by the 2006 storm (also often referred to as the ‘Big Snow’), which left many residents without power for weeks.

Interesting that where in the past a severe or any snowfall here was considered a RARE event, and usually with a several year gap between events, we now have severe snow falls in 2011 (2) and in 2012 one already!

Why oh why did we go from global WARMING, to climate CHANGE??? I'm freezing down here!

My office just shook a little here on Crete Island, Greece. I'm waiting to see if EMSC will show something

And a little M4 to wake the Irish!

Not something one sees too often, methinks.

Added:

Irish earthquakes are as rare as hen’s teeth, which is really quite curious. The geology of Ireland is very similar to that of the rest of the British Isles and many of the geological structures in the UK can be traced into the Republic. However, whilst Great Britain has a modest level of seismicity, ‘Lesser’ Britain virtually has none.

The largest quake off the Irish Coast was a M5.4 in 1984...even this M4 ranks in the higher scale as most experienced in this region are