Quake Watch 2012

following on from post by muzzy

then...................
if you are really curious ( like I am) you'll click over to NZ Earthquake Swarms and click on Whale Island in the "Swarm Series" box and be surprised (as I was, as I had forgotten this was ongoing after I posted it, but I never followed through) that it went on for quite a while.
I'm just doing a map for that 19th May, and will post it there when I'm one. Won't bother with the list like I had been doing, 130 lines

See how I get sidetracked, I was going to update my RAS page today.


actually only 67 of those 130 were Whale Island.
Busy day none the less
NZ May19th Revised and Updated

Originally posted by muzzy

Originally posted by BO XIAN
reply to post by muzzy

 

What, please, are your insights, conclusions, inferences . . . speculations from the wonderful graphs shown here:

seabreeze.wordpress.com...
???
I haven't the time to examine them real closely. There seems to be some significant variability--as in average activity variability--that is--averages of the activity seem to be quite different--from year to year.

I have no idea, looks totally random to me.

Don't forget only 2009 and 2010 are comparable, as they are "final" data +/- 500 odd un-estimated magnitude events

What visitors are supposed to do is look at the graph, say 2010, figure out what day they want to look at, (the Days are numbered 1-365) then use the search function (top right hand column) to see what was happening.
for example lets have a look at day 139 which had 130 quakes in 24hrs but no colouring to the column, so not a 5+?, so day 139 is May 19, search 19.05.2010 .........

Wellllllll, it looks like a wonderful thing to study and play with.

I really enjoy aggregate data like that . . . to see what inferences or significant changes or patterns one might ferret out.

Thanks thanks.

There has just been a 6.0 logged at EMSC in the Dodecanese Islands (Greece) at 30 depth - significant for that area - unable to copy and paste as EMSC is down/over loaded at the moment,

aha ! USGS has caught up but has it lower at 5.7 - will they defer to EMSC for pinpoint accuracy on this one I wonder ???

earthquake.usgs.gov...

reply to post by slidingdoor

Yes, I'm getting the same issues with EMSC. Their servers seem to have quite limited capacity, really.

Here's the data page from USGS (at this link )

Magnitude 5.7 - DODECANESE ISLANDS, GREECE

2012 June 10 12:44:15 UTC

Details
Summary
Maps
Scientific & Technical
Additional Info

Earthquake Details

This event has been reviewed by a seismologist.

Magnitude 5.7
Date-Time

Sunday, June 10, 2012 at 12:44:15 UTC
Sunday, June 10, 2012 at 03:44:15 PM at epicenter
Time of Earthquake in other Time Zones

Location 36.446°N, 28.930°E
Depth 20.4 km (12.7 miles)
Region DODECANESE ISLANDS, GREECE
Distances 63 km (39 miles) E of Rodos, Dodecanese Islands, Greece
98 km (60 miles) SSE of Mugla, Turkey
147 km (91 miles) S of Denizli, Turkey
425 km (264 miles) WNW of NICOSIA, Cyprus
Location Uncertainty horizontal +/- 10.8 km (6.7 miles); depth +/- 6.8 km (4.2 miles)
Parameters NST=433, Nph=433, Dmin=188.1 km, Rmss=1.18 sec, Gp= 43°,
M-type=regional moment magnitude (Mw), Version=A
Source

Magnitude: USGS NEIC (WDCS-D)
Location: USGS NEIC (WDCS-D)

Event ID usb000ac4h

Guessing EMSC might reduce their number. Or USGS will up theirs. We'll see.

In either case it's pretty shallow as quakes go.

No damage reports in yet that I could find.

Mike

lol Mike , you just beat me to it !!!

Well, in theory I would assume and perhaps wrongly assume that given the EMSC's HQ they should be better placed to measure this one ???

reply to post by slidingdoor

One would think that EMSC is better placed for this one, yes.

Also, even the phase data page for this quake on NEIC/USGS states 5.8 mb, and as that works out at around 6.1 Mw (or a bit more) I cannot figure why they show it on the map and main data page as a 5.7!

And by the way:

lol Mike , you just beat me to it !!!

Yeah, but you got the first info posted!

Mike

Thanks to member 'Lover088' for this link - he/she started a separate thread on this quake but I'm liking this Hellenic Geo dynamics site for keeping an eye on the area :

bbnet.gein.noa.gr...

Edit to add : Oh No's !!! Now that site is over whelmed too !

reply to post by slidingdoor

Yes, it's doubtless being deluged at present but I've bookmarked it for future reference.

That quake was big enough to be of some concern in that region so I'm not surprised that the traffic to such sites is high now.

I just checked with Aegean Press and they say:

Ισχυρή σεισμική δόνηση συνέβη στις 15:44, 73 χλμ Ανατολικά της Ρόδου.
Ο σεισμός 6,2 βαθμούς της κλίμακας Ρίχτερ έγινε αισθητός και στην Αθήνα.
Δεν έχουν ανακοινωθεί ζημιές η τραυματισμοί.

Which via an online translator gives us:

Strong Earthquake occurred on 3:44 PM, 73 km east of Rhodes.
The earthquake measuring 6.2 degrees in Richter scale was felt in Athens.
Have not been announced damage the injuries.

Okay, so (likely from EMSC or the Greek's own seismo Institute) they say it's a 6.2. That matches up much better with the 5.8 mb that USGS provided (as noted in my post just above).

But no injuries or damage reported as yet. Good news. Let's hope it stays that way.

Mike

I'm with you on that Mike - the structures on those islands aren't built to withstand though .... Where's the aftershocks too by the way ???

Also being initially 'depthed' (no such word!) at 30 i.e. shallow what effect will that have on the waters/sea around there ? Not talking tsunami necessarily but the poor fishermen !!!

reply to post by slidingdoor

Yes, I've been to Rhodos and while it's a lovely place, there are lots of older buildings that are not constructed to high standards of quake resistance. Most of the more modern ones are better, though. Rebar in concrete for foundations and so on. (I knew a local there who built his own hotel and he used lots of rebar. Local codes required it and he figured it was better to be safe than sorry anyway.)

About aftershocks: it's still very soon after the quake. There might be some aftershocks, but if they're down in the mag 4 range we'll have to wait until we can access one of the regional sites. If they're say 4.5 or bigger USGS might put them up. (Over 5.0 they will).

Quakes around 5.0 or less are unlikely to be have a lot of effect on the surrounding waters. Even this bigger one might not have stirred things up too much in that regard. The fishing boats should be fine. The main worry is buildings that are not too far away. (Actually Turkey is closer.)

EDIT to add: pretty well zero chance of a tsunami. Even at mag 6 or thereabouts the energy release is very small compared to (say) Japan's mag 9.0 last year. A mag 9.0 is 1,000 times stronger than a mag 6.0 and releases almost 32,000 times more energy. (ie it takes almost 32,000 mag 6.0 quakes to release the same amount of energy as ONE mag 9.0 quake!)


Mike

Yes , it is much closer to Turkey and the popular resorts along the Turkish coast.

geofon.gfz-potsdam.de...

Hmm... On another site I've just found that there was a second quake -- a mag 5.5 -- just a few minutes after the (?) 6.2.

It's reported on the kosvoice.gr website and is their top story on the main page right now. If you click on the report there it takes you to a new page, which I can't link direct as its Greek characters in the URL come out malformed.

The report's headline says:

Χαμός με τους σεισμούς: 6,2 & 5,5 ανατολικά της Ρόδου-Αισθητοί και οι 2 σεισμοί στην Κω

This (babylon translator) translates as:

shambles where with earthquakes: 6.2 * 5.5 east of Rhodes-felt and 2 earthquakes in Kos

Then it goes on to say:

Στις 15:44 περίπου έγινε σεισμός 6,2 ρίχτερ 73 χιλιόμετρα ανατολικά της Ρόδου όμως έγινε αισθητός και στην Κω. Ο σεισμός είχε διάρκεια ενώ σίγουρα θα ακολουθήσουν μετασεισμοί. Επίσης στις 15:49 έγινε ακόμα ένας 5,5 ρίχτερ 71 χιλιόμετρα ανατολικά της Ρόδου. Νότια της Πάτμου 06:36 2,6 ρίχτερ 28 χιλιόμετρ.

Babylon translator:

At 3:44 PM around it was an earthquake measuring 6.2 Richter scale 73 kilometers east of Rhodes, but it was also felt in Kos. During the earthquake and it certainly will be followed by aftershocks. Also in 3:49 PM got a 5.5 on the Richter scale 71 kilometers east of Rhodes. South of Patmoy, Mandrakioy 06:36 AM 2.6 Richter 28 χιλιόμετρ.

So it means there was a 6.2 followed by a 5.5 about five minutes later a couple of km away from the first one.

I haven't seen the 5.5 posted yet on USGS (and EMSC is still down). We'll see if this second quake gets confirmed by another seismo service.

Mike

Turkey's academic based Kandilli Obs. already list more than 10 aftershocks.

There's also official gov agency Deprem, but overloaded at moment.

alternative while EMSC CSEM and NOA DDoSed offline

www.koeri.boun.edu.tr/.lst9.asp

reply to post by mlirenr


Excellent ! and decreasing nicely too . That's a useful site right now , so thanks.

EMSC and the Hellenic sites aren't so busy now and just let me back in . Emsc is behind the curve and yet to log the aftershocks but the Hellenic site has a 5.1 listed straight after the 6.0 Mike.

reply to post by mlirenr

Brilliant resource. Many thanks! (Another one for my lonnng list of bookmarks!)

I'd guess the one the Turks list as a 4.9 was the 5.5 reported by Kosvoice. Being so soon after the main shock it's not surprising that there's some degree of variation there.

Mike

Originally posted by slidingdoor
reply to post by mlirenr

 

[...]
EMSC and the Hellenic sites aren't so busy now and just let me back in . Emsc is behind the curve and yet to log the aftershocks but the Hellenic site has a 5.1 listed straight after the 6.0 Mike.

I kind of got back in to EMSC a minute ago. No in-site links worked, but the Mediterranean map was up and it showed the main quake as a mag 5.9, the largest aftershock as 4.9.

At this stage that's close enough agreement to what others in the region have said.

USGS is stubbornly sticking to 5.8. (And they dropped their mb 5.8 to 5.7 just after I posted the linky to the page...)

Mike

Some injuries but no deaths fortunately.

in.reuters.com...

does anyone know if we've been having a higher than normal amount of quakes over a 5.5 ? i guess i'm thinking in the last 3 months we've had an unusual amount of them but i don't know enough about quakes to know.

reply to post by pasiphae

Actually things have been pretty quiet in the past couple of months or so. There have been a fair number of lower mag 5 quakes and some in the 5.5 and bigger, but nothing extraordinary by any stretch. And mag 6-range quakes lately have been pretty much on average. (We average one every two or three days, worldwide. And that's roughly how it's been.)

As for larger events, the last mag 7 (or bigger) quake was in the Gulf of California on April 12 (a mag 7.0). That's 60 days or so without a mag 7-something. Considering on average we get about 15 such quakes per year (about one every 23 days or so on mathematical average), that's a fair break.

However, we've gone longer than that before without a biggish event. Many times. Then we can get two or three in a day or so. They're like that sometimes.

I guess one reason that it might seem it's been rather busy is because unfortunately, some of the mag 5-range quakes have caused casualties -- especially those in Italy in the latter part of May. So, quakes have been in the news lately and that heightens public awareness for a while. But honestly, the overall number of mag 5.5-plus quakes has certainly not been anything unusual. They can vary a fair amount in a shorter time period but it means little. It's only when we look at long-term averages that we get a better idea of roughly how many is "normal".

Take those mag 7 or bigger events. To compute an average I referred to the Centennial Earthquake Catalogue (on the USGS website), that covers the entire 20th century. It lists 1553 such quakes. Hence the roughly 15-per-year average. Some years had less, some more, but even fairly big short-term changes upwards or downwards don't mean a great deal in the bigger picture of things.

Mike

reply to post by JustMike


thanks for that info mike! i'm glad i asked.