Quake Watch 2011

I can't get anything after 23:21 yesterday now....our time or utc I have no clue.
If they weren't in Canberra I'd be tempted to go give em a kick up the backside. This area is not one of their strong points, obviously because quakes are a non issue in this country. grrr.

reply to post by zenius


Sorry, forgot to point you at this:

Empirical Global Relations Converting M S and m b to Moment Magnitude

By the way you can download that from scribd as a PDF without having to pay which is unusual!

Enjoy!!

Found this one as well Empirical Relationships For Magnitude And Source-To-Site Distance Conversions Using Recently Compiled Turkish Strong-Ground Motion Database (PDF)

reply to post by PuterMan


Geeez, you wanna make my brain hurt tonight?
Surely there must be an online calculator or downloadable one?
I didn't do well at maths.

reply to post by zenius


My brain hurts so why shouldn't yours!! Likewise on the maths.

I will see what I can find and perhaps I will create one if I can't find anything.

Here is an even worse one (PDF) just to keep you occupied

reply to post by PuterMan


NO PLEASE NO MORE!

Yes, I think in your spare time (hahaha) you might need to create the program. Page 4 on google search and still nothing. You'd think someone would've developed it by now and made it available for us commoners.


Oh, you'll like this one:
www.ajdesigner.com...

Would you put that one on your links please?

reply to post by zenius


I got a few more pages down the list.

Here are my results.

qvsdata.wordpress.com...

reply to post by PuterMan


My bad. I am in error with this statement.

I had for some reason assumed that this referred to the 7.0 (USGS) earthquake and had not thought about the 6.3 recently.

As JustMike has pointed out to me this Japanese quake would indeed have been about 8000 times stronger than the 6.3 in NZ.

Shows you what a difference .7 makes!

Magnitude 5.3 - GULF OF CALIFORNIA
earthquake.usgs.gov...

* This event has been reviewed by a seismologist.

Magnitude 5.3
Date-Time

* Saturday, March 12, 2011 at 14:11:04 UTC
* Saturday, March 12, 2011 at 07:11:04 AM at epicenter

Location 25.396°N, 109.652°W
Depth 12.1 km (7.5 miles)
Region GULF OF CALIFORNIA
Distances

* 75 km (46 miles) SW (220°) from Ahome, Sinaloa, Mexico
* 80 km (50 miles) WSW (239°) from Los Mochis, Sinaloa, Mexico
* 91 km (57 miles) WSW (245°) from Juan Jos� R�os, Sinaloa, Mexico
* 1069 km (664 miles) SE (136°) from Tijuana, Baja California, Mexico

Location Uncertainty horizontal +/- 20.8 km (12.9 miles); depth +/- 3.7 km (2.3 miles)
Parameters NST=165, Nph=166, Dmin=191.5 km, Rmss=1.2 sec, Gp=133°,
M-type=body wave magnitude (Mb), Version=7

4.4 2011/03/12 12:03:42 25.260 -109.964 10.1 GULF OF CALIFORNIA
4.4 2011/03/12 10:17:08 18.899 -107.111 33.5 OFF THE COAST OF JALISCO, MEXICO

reply to post by zenius


I have added that link thanks. I have placed it at the head of the page that I linked to just a while ago, which was not in the menuing system. It now is in the menus and can be accessed here.

[atsimg]http://files.abovetopsecret.com/images/member/addfbd64325b.png[/atsimg]

Actually I have to say an event bigger thank you because I have been able to use that link to verify that the formula I have been using to calculate seismic energy is correct. I was fairly certain it was, despite my poor maths abilities, but that site came up with the exact same value for a 7.5 that I get.

reply to post by Hx3_1963


Last 30 days:

Date/Time UTC,Latitude,Longitude,Magnitude,Depth(Km),Location
2011-03-12T14:11:04.000Z,25.39560,-109.65170,5.3000,12.1000,Gulf of California
2011-03-12T12:03:42.000Z,25.36000,-109.76000,4.5000,2.0000,GULF OF CALIFORNIA
2011-03-12T12:03:42.000Z,25.25970,-109.96420,4.4000,10.1000,Gulf of California
2011-03-02T19:08:28.000Z,31.86320,-114.89480,2.5000,10.0000,Gulf of California
2011-02-22T09:33:05.000Z,23.77250,-108.62430,4.0000,10.0000,Gulf of California

I have a question related to the following Japan earthquake:

11-MAR-2011 19:46:49 40.47 139.07 6.6 1.0 NEAR WEST COAST OF HONSHU, JAPAN

Depth - 1 KM. This is so out of pattern , I wonder what could cause a 6.6 earthquake located less than a mile under the earth? Any guess / theory?

reply to post by Romanian


Not sure what info you are looking at but the information I have on my database is 10km and this is confirmed by the USGS page for the event

earthquake.usgs.gov...

Now since 10km is a default depth the depth might be poorly constrained and if this is the case then perhaps your source uses 1 km as a default. Other than that I think a 6.6 at 1 miles is probably unlikely.



Just checked EMSC and they also say 10km so it may actually be 10km.


Further confirmed by the Japanese database as 10km depth

www.jma.go.jp...

reply to post by PuterMan


Oh, interesting. My website is this one:


www.iris.edu...

Originally posted by Romanian
reply to post by PuterMan

 

Oh, interesting. My website is this one:


www.iris.edu...

Now that IS very curious.

The USGS and EMSC will be using the same data and yet both get 10km.

See my addition to my post about the Japanese database.

Have to have a think about this.

We have two scenarios:

1) IRIS is wrong
2) IRIS is right and the other sources are modified so they do not look suspicious. Someone forgot to change IRIS.


ps: yesterday evening , yours source would also show 1KM, now it is changed to 10..

reply to post by Romanian


I can check that since I keep all revisions and deletions. Wait one...........

Yes it was 1 km at some stage

c0001z4n us 6 2011-03-11T19:46:49.000Z 40.47200 139.07000 6.6000 Mi 434 10.0000 near the west coast of Honshu. Japan
c0001z4n us 6 2011-03-11T19:46:49.000Z 40.47200 139.06950 6.6000 Mi 434 1.0000 near the west coast of Honshu. Japan
c0001z4n us 2 2011-03-11T19:46:49.000Z 40.47200 139.07000 6.6000 Mi 434 10.0000 near the west coast of Honshu. Japan

Just going to get into the database and check the logged ID numbers to make sure the order of events.

reply to post by Romanian


ps: IRIS shows more odd quakes too:

11-MAR-2011 18:59:15 37.04 138.36 6.2 1.0 NEAR WEST COAST OF HONSHU, JAPAN
11-MAR-2011 18:39:33 37.92 143.06 4.9 1.8 OFF EAST COAST OF HONSHU, JAPAN
10-MAR-2011 16:54:45 38.05 143.25 5.2 4.7 OFF EAST COAST OF HONSHU, JAPAN
09-MAR-2011 18:44:35 38.49 143.19 6.3 2.0 OFF EAST COAST OF HONSHU, JAPAN

reply to post by Romanian

I just checked it on the Japan Meterological Agency site. That quake was at 04:47 JST on March 12. It's been assessed by the JMA as a mag 6.4 (rather than a 6.6), but they also give the depth as 10km.

Here's the linky to the details.

Note: pages are in English.

I doubt that this is a default depth. If we check their latest quake list and click on a few listed quakes, they show a good range of depths. Looks like this one was really 10 km, which is still very shallow.

Another note: JMA posts the magnitude details on their site according to international standards, but you'll also see some info which relates to their own scale, which has a maximum of 7. If you watch reports on Japanese news channels it's important to know this because the TV networks in Japan will often post the magnitude both in the JMA scale and the moment magnitude scale that we tend to use these days.

Mike

reply to post by Romanian


OK these are the two revision records out of the database. The 1km depth came first and then the 10km which is shown incorrectly above as it should be in descending order (*note to self - fix this*)

c0001z4n us usgs 6 2011-03-11T19:46:49.000Z 40.47200 139.06950 6.6000 Mi 434 1.0000 near the west coast of Honshu. Japan 0 0 95439
c0001z4n us usgs 2 2011-03-11T19:46:49.000Z 40.47200 139.07000 6.6000 Mi 434 10.0000 near the west coast of Honshu. Japan 1 1 95447

The last number is the ID. The higher the ID the later the record. These are automatically assigned and cannot be altered. The curious thing is that the 4th item 6 and 2 respectively is the USGS own version number, which would indicate that they put our version 6 before version 2

Since the Japanese database says 10km I would be inclined to go with that as say that IRIS is in error having not updated that field since the first data, but I also find that very odd as well.

I am not sure how IRIS works.. is this working with LIVE feed from other sources, or trying to interpolate from their own sources?