Magnitude 7.2 - MAULE, CHILE

Sunday, March 25, 2012 at 22:37:06 UTC Sunday, March 25, 2012 at 06:37:06 PM at epicenter Time of Earthquake in other Time Zones

Location 35.198°S, 71.783°W Depth 30 km (18.6 miles) Region MAULE, CHILE Distances 27 km (16 miles) NNW of Talca, Maule, Chile 55 km (34 miles) WSW of Curico, Maule, Chile 99 km (61 miles) NNE of Cauquenes, Maule, Chile 219 km (136 miles) SSW of SANTIAGO, Region Metropolitana, Chile Location Uncertainty horizontal +/- 19.8 km (12.3 miles); depth +/- 6.7 km (4.2 miles) Parameters NST=336, Nph=342, Dmin=24.5 km, Rmss=0.84 sec, Gp= 94°, M-type=regional moment magnitude (Mw), Version=7 Source

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“steady increase in the intensity of 8.0 or higher quakes and the effects they are having on the earth is even more frightening.”

The number of 8+ earthquakes are too small to apply any kind of statistical analysis to in the manner you are assuming.

Here is a good broader analysis:

http://arstechnica.com/science/news/2011/12/cluster-of-80-magnitude-earthquakes-doesnt-indicate-earth-is-more-active.ars

The authors went through the US Geological Survey’s historic records, identifying every earthquake above magnitude 7.0 that occurred between 1900 and 2011. To eliminate aftershocks and local strain caused by initial earthquakes, the authors set a cutoff: any smaller earthquakes within three years and 1,000km of a quake were considered its aftershocks, and not incorporated into the analysis. This is a fairly liberal definition of aftershock, and takes two recent monster quakes out of the analysis, both over 8.5 and near the site of the first Sumatran quake. But it is consistent with what we know about how major quakes can add strain to areas at a considerable distance from where the fault actually ruptured.

The authors also justify this exclusion by noting that they actually care whether there’s an uptick in global levels of activity, so local clusters of quakes shouldn’t alter their analysis. In addition, they note that some of the statistics are fairly insensitive to the selection criteria—you can cut the distance by a third and still get similar results. Still, this is a pretty significant cutoff, since it greatly reduces the frequency of recent, large quakes.

One thing that their analysis makes clear is that the overall rate of large earthquakes—those over magnitude 7.0—is about average right now. It’s just that more of those quakes are above 8.0. We are experiencing a record level of 8.0+ quakes, but it’s only slightly above previous records.

Is that record level especially unusual? The authors randomized their earthquake catalog 100,000 times to get a statistical sense of the typical earthquake clustering. When selecting for magnitude 8.0 and above, 85 percent of these randomized sets contained an earthquake cluster similar to the one we’ve experienced since 2004. When the event size was raised to 8.5, 97 percent of the randomized sets contained a cluster like our recent one. A series of additional tests indicate that the distribution we see is consistent with a Poisson process, which indicates they are occurring randomly.

That large difference highlights the importance of the cutoff you choose in terms of magnitude. To get a greater sense of this, the authors took their randomized set and performed a stepwise analysis of it, starting at magnitude 8.0 and raising the cutoff by 0.1, looking for clusters at each cutoff. Three quarters of the resulting sets had a cluster that should occur only five percent of the time in a single random set. Just under a third had a cluster that should occur less than one percent of the time.

Is there anything unusual in the record? Sort of. There were no events greater than magnitude 8.5 for nearly 40 years, a gap that started in 1965 after an enormous Alaskan earthquake. In the randomized collection, this only showed up in 1.3 percent of the sets. But again, the authors point out that this depends on setting a very specific cutoff. In any case, that unusually large gap may have made the recent spate of large quakes more notable.

Overall, the authors conclude that globally, earthquakes are not clustering over time. There may be local clusters that were eliminated by their selection criteria, but we have mechanisms that can explain why local clusters should occur. And that highlights another issue the authors have with the idea of a global cluster: we don’t know of any mechanism that could possibly create one.

I figured that would be your reaction. A sober statistical analysis is far less interesting albeit far more illuminating.

There simply aren't enough very large earthquakes over the last 100 years to make your kind of assumptions as to any statistical relevance to what we have been seeing as of late. A clustering of three very large earthquakes in recent times may seem significant, but those happened after a fairly quiet period after the 1964 Alaska quake up until the Sumatra quake in 2004. That Alaska quake was in turn part of several very large earthquakes in a 13 year span - a 9.0 in 1952 in Kamchatka, and then the biggest earthquake in recorded history, the 1960 9.5 Chilean quake, and the Alaska 9.2 in 1964. And there were some 8.7 and 8.6 quakes peppered in during that time as well.

So if anything, our current cluster is more akin to rhe era of 1952 to 1965. If anything, the quakes in that cluster were even somewhat more powerful.

You're wasting your time.

I don't care what has happened over that past 100 years because the only years that are relevant are the sixty-three years since Israel was re-established as a nation.

And the evidence is in that earthquakes, especially those in the larger magnitudes, have increased in frequency and intensity. The fact that this is happening at the same time as every single sign that Jesus Christ gave for His return gives these earthquakes enormous significance.

Now you may scoff at that, and that's perfectly okay. Your laughing and contempt could not be more meaningless. You can deny these things are happening, including the increasing frequency of earthquakes, until a new world is built and it is totally meaningless and will not change one thing. There is ample evidence that earthquakes are increasing, and the proof of that was provided.

You're not going to change my mind. Stop wasting your time.

I don't care what has happened over that past 100 years because the only years that are relevant are the sixty-three years since Israel was re-established as a nation.

The earthquakes I mentioned - with two of them STRONGER than the earthquakes of recent years - 1952, 1960 and 1964 - were during that timeframe. And then there was a long quiet period.

I am not engaging in laughing and contempt. But when you made a statement of fact (major earthquakes are increasing recently) coupled to your statement of faith, well, I asked you to back up that statement of fact. And you did not and have dismissed two polite presentations that call into question the veracity of your statement of fact. If you choose to ignore that contradiction, well, that's up to you, and I can't change the mind of someone who has chosen to take that path.

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