Quake Watch 2012

reply to post by Xtrozero


Ahhhh so you are o the Phage school of thought, where aftershocks are not counted, even if they are Mag 8 or 7

Sorry I don't buy into that, the two Sumatra quakes were hundreds of km apart, so although you could say the second one was an aftershock, it was also an earthquake event in its own right.
Thinking like that will skew the number count or sure.

I don't buy into the "we got more seismographs now" train of thought either, its pretty hard to miss a Mag 7 anywhere in the World, all the extra siesmos are doing is picking up the lower magnitude ones 3's and 4's.
I have been tracking the LISS SNZO station graphs for 6 months now and there are traces on there that have yet to be identified by USGS, GFZ or anyone else, I believe they are out in the South Pacific, Southern East Pacific Rise, Pacific/Antarctica Ridge, South of Australia or thereabouts, and based on previous traces they are in the low Mag 5 range, so having more siesmos in the USA makes no difference, you need them where there are no people to report quakes, like on Campbell Island, unfortunately the penguins there don't have laptops available to send in their quake reports

Magnitude 6.1 OFF W COAST OF NORTHERN SUMATRA

Location in Google Maps

Derived from Data Source: EMSC
Powered by QVSData


And the same event from USGS

Magnitude 6.1 off the west coast of northern Sumatra

Location in Google Maps

• Date-Time: Saturday, April 21, 2012 @ 00:14:32 UTC
  
• Earthquake location 2.218°N, 93.395°E
  
• Depth: 34.3 km ± 6.6 km
  
• Region: off the west coast of northern Sumatra
  
• Distances:
  333km (206mi) from Sinabang, Indonesia
  370km (229mi) from Meulaboh, Indonesia
  426km (264mi) from Banda Aceh, Indonesia
  451km (280mi) from Sigli, Indonesia
  927km (576mi) from Kuala Lumpur, Malaysia
  
• Mag Source: USGS National Earthquake Information Center
  
• Event ID: usc00098ln
  

Derived from Data Source: USGS
Powered by QVSData


EMSC now down to 6.1 Mw

Tsunami Event

It is likely that a tsunami was generated. Based on precalculated scenarios, the maximum tsunami wave height near the coast of Datimun will be 2.38m.

A detailed tsunami wave height calculation is ongoing and should be available 20 minutes after this report was created. Results can be slightly different than the precalculated scenario. The outcome can be checked here: GDACS tsunami report .

Travel time map.

Other maps: maximum wave height, animation.

Earthquake Event Characteristics Source: World Data Centre for Seismology, Denver (NEIC) M Magnitude: 8.2 M Depth: 16.4 km Location (Lat/Long): 0.7731 | 92.4522 Country: Indonesia Province: Aceh Region: Off The West Coast Of Northern Sumatra UTC/GMT (Greenwich time): 4/11/2012 10:43:09 AM Estimated local solar time: 4/11/2012 4:52:58 PM

reply to post by muzzy

I don't buy into the "we got more seismographs now" train of thought either, its pretty hard to miss a Mag 7 anywhere in the World, all the extra siesmos are doing is picking up the lower magnitude ones 3's and 4's.

I have been tracking the LISS SNZO station graphs for 6 months now and there are traces on there that have yet to be identified by USGS, GFZ or anyone else

I would have to say that this is not the case in my opinion, at least not entirely, and indeed your second statement denies the first to a degree. We know that the events missing on SNZO are often probably around Mag 5 not 3 and 4. In addition I would not mind betting that the additional seismos anywhere NOT in the US are picking up additional information of mag 5s as well.

In May last year I looked at publicly available seismos at that time, the _REALTIME list. Here is the post about this. You can see how totally skewed towards the US the distribution is.

I agree that Mag 7 have been 'visible' to seismographs around the world since 1900 or earlier but even those may not be accurate and may not have properly identified teleseisms. Don't forget it was not really until the advent of the Woods-Anderson that more accurate recording was available, and even then more for local quakes.

You can only really depend on the data since around the 1960s although 1930 is the cut off date for Mag 6.5 in the Centennial.

Many earlier events are based on historical evidence that is nor verifiable in many cases and is often subjective. You have only to look at the huge range of modern day felt reports, even within the same locality sometimes to see that errors, in both directions, can occur with earlier earthquakes.

As it happens, and as I stated, 16 is my number for Mag 7 this years and 132 for Mag 6. We shall see.

reply to post by BobAthome


OK, where are you seeing this tsunami information. I can't find it anywhere and there is no alert on NOAA, nor is there any tsunami tab on the USGS pages old or new.

It is not even on the GDACS page for the quake

reply to post by PuterMan


A relevant paper is

Global seismic event detection using a matched filter on long-period seismograms
Shearer, PM
J. Geophys. Res. Solid Earth, Volume: 99 Issue: B7 Pages: 13713-13725 DOI: 10.1029/94JB00498 1994

He looked at the years 1981-1991 with an automatic method to see what events were missed. From the abstract, "32 earthquakes are detected which are not in the standard global catalogs. These events appear to be about M(s) = 5 and are mainly located in the southern oceans, where there are gaps in the coverage of the high-frequency networks."

Coverage is better now, so about M5 would be an upper limit on what global networks miss. However, it is true that in the minutes after a huge earthquake, large earthquakes might be missed. For example, 20 minutes after the Japanese M9 last year, there was a low-energy M8 that went several days before being noticed.

reply to post by PuterMan


That tsunami warning must have been the initial report for the M8.2 that followed the M8.6 last week, according to the time and location. Before they realized it was a strike-slip event that would not generate much of a wave.

With my eyes off the prize because I was watching Antarctica, I failed to notice there is a lull in one small region. Yellowstone has been quiet. But that's not the absence of quakes which has me wondering. It's the region to the northwest of Yellowstone. There's usually something going on. It's been real quiet. Probably nothing.


www.msnbc.msn.com...

www.businessweek.com...


www.smh.com.au...

www.washingtonpost.com...

Oh, I almost fracking-muckrucker-ratraper-countryluvin-mutherfrackin'-nutbustergutbusters forgot. They say the increase in midwest quakes have nothing to do with fracking. Oh, where's my Daleks.

reply to post by PuterMan


Has THIS been posted?

What is the consensus on these quakes happening in the state of Washington, USA?

Interesting.....

reply to post by PuterMan

Datimun
Friday, 20th April 2012 at 11:14 PM
----------------------------------------
Datimun 4/11/2012 4:52:58 PM


Datimun 20th April 2012 at 11:14 PM
Date-Time [UTC]: Friday, 20th April 2012 at 11:14 PM
Local Date/Time: Friday, April 20, 2012 at 05:14 at night at epicenter
Coordinate: 2° 13.062, 93° 23.694
Depth: 34.30 km (21.31 miles)
Hypocentrum: Shallow depth
Class: Strong
Region: Indonesian archipelago
Country: Indonesia
Location: 269.3 km (167.34 miles) - of Datimun, Indonesia,,

same area,,,,
why no Tsunami this time?,,,lets assume its an interesting,, possibly significant,,difference.
why no Tsunami?
it's still a 6.1 and or a 6.3
and yes it does seem to be strong enough,,and shallow enough,,
why no Tsunami?
Just curious.
Me.

reply to post by amongus


We seismologists do not consider them alarming - just the normal variations in levels of seismicity.

Originally posted by muzzy


I don't buy into the "we got more seismographs now" train of thought either, its pretty hard to miss a Mag 7 anywhere in the World,

So you dont think previous to seismographs and a nearly instantaneously-connected world people would have been aware of an earthquake in the third world?

Really?

So, despite all the actual evidence that shows these are normal, provable cycles, you stil prefer to believe something unique is happening?

Perhaps I misunderstand your point.

Apppologies.

Magnitude 6.6
Date-Time
Saturday, April 21, 2012 at 01:16:54 UTC
Saturday, April 21, 2012 at 10:16:54 AM at epicenter
Time of Earthquake in other Time Zones
Location 1.609°S, 134.232°E
Depth 29.8 km (18.5 miles)
Region NEAR THE NORTH COAST OF PAPUA, INDONESIA
Distances 83 km (51 miles) SSE of Manokwari, Papua, Indonesia
341 km (211 miles) ESE of Sorong, Papua, Indonesia
990 km (615 miles) S of KOROR, Palau
1258 km (781 miles) NNE of DARWIN, Northern Territory, Australia
Location Uncertainty horizontal +/- 13.8 km (8.6 miles); depth +/- 4.9 km (3.0 miles)
Parameters NST=205, Nph=206, Dmin=263.8 km, Rmss=1.39 sec, Gp= 18°,
M-type=regional moment magnitude (Mw), Version=A
Source
Magnitude: USGS NEIC (WDCS-D)
Location: USGS NEIC (WDCS-D)
Event ID usc00098nl

earthquake.usgs.gov...

Originally posted by muzzy

Magnitude 6.6
Saturday, April 21, 2012 at 01:16:54 UTC
Region NEAR THE NORTH COAST OF PAPUA, INDONESIA

And this is what it looked like on my home built seismometer...

another one in papau nu in the same place as the one a couple hours ago.

reply to post by stanguilles7


Absolutely.
Depending how far back you want to go.
They would have heard about it a bit later than nowadays of course.
I have pdf's of Tsunami Reports from Samoa going back to 1837

On the 7th of November 1837, there was an earthquake
in Chile , and a sea wave started by it was felt at
the Hawaiian Islands; also at Tutuila in the Samoan
Group. (Hitchcock, 1911)

Thats 175 years ago, and they even gave the exact date
Cross referencing with the records the Chileans have, we find that in fact it was a Mag 8.0, at1130UTC, Lat-39.8, Long -73.2, Valdivia, Concepcion

Back then it was the duty of sea captains, Consul-Generals, in fact anyone connected to the colonial governments, to make notes in their diaries of any untoward events, including tsunamis, earthquakes and cyclones. Thats where the records come from for the 19th Century.
Sure they might be a bit off on the magnitude, but don't make me laugh by saying the USGS is accurate today with all the technology they have at hand (example the off W Sumatra quake today it was it a 6.2?, 6.1?, 5.7 ? they likely less clue than the local villager in Tangi.)

Its the same with historic Chinese, Syrian and Turkish quakes the information is there, if you look for it.

To assume there was no recording of earthquakes before USGS, or that if there was, it was inaccurate is just plain dumb..(note: not directed at anyone on here personally)

reply to post by muzzy


So, when scientists look at geological records for the area and show sings of these same sorts of clusters of large quakes, what does that mean?

"Researchers found evidence of this growth pattern about every 200 years, and say the changes to the coral reefs in the region weren’t caused by one single giant earthquake.

Instead, the growth patterns indicate that each cycle involves a few major earthquakes that occur over the course of several decades, in what study coauthor Aron Meltzner calls a “supercycle.”"

blogs.discovermagazine.com...

reply to post by PuterMan


Since it is already the 21st in UTC time...let me be the first to say.....

Happy Birthday to you!
Happy Birthday to you!
Happy Birthday dear Puterman!
Happy Birthday to Yooouuuuuu!!!!!

And perfect timing with a 6.6 (earthquake) firecracker !!!
WOQ

reply to post by PuterMan

I'm just saying having more seismograms now doesn't necessarily mean more quakes counted, especially in the 7+ range. All the extra new machines are in the wrong places.
Happy Birthday by the way

Quick update from here in Phuket.

The Thai authorities have finally updated their website somewhat. The english version works a little bit now. But overall the Thai version is better I suggest you use google translate on the page.

One thing that is particularly interesting is they have added a seismometer and web link for Thalang Phuket. I have felt every aftershock above a 2.0! Link to webicorder this is about 500m from my home.

Here is the link to the Seismological Bureau of Thailand thats the english page, top right link goes to the Thai Site which is much more detailed but as I mentioned before, needs to be read with google translate. (Unless you read Thai of course )

Hope thats of interest to some, thought I'd share.