Nearly 1,000 earthquakes recorded in Arizona over 3 years

Aug 14, 2012
Nearly 60 USArray stations were installed in Arizona from 2006 to 2009 as part of the EarthScope project. Station 118A, seen in this photo, recorded ground motion north of Wilcox in southeastern Arizona from April 6, 2007 to Jan. 21, 2009. Credit: Incorporated Research Institutions for Seismology (funded by NSF EarthScope)

Arizona State University researchers use EarthScope data to build the first comprehensive earthquake catalog for Arizona.

Earthquakes are among the most destructive and common of geologic phenomena. Several million earthquakes are estimated to occur worldwide each year (the vast majority are too small to feel, but their can be measured by arrays of ). Historically, most of Arizona has experienced low levels of recorded seismicity, with infrequent moderate and large earthquakes in the state. Comprehensive analyses of seismicity within Arizona have not been previously possible due to a lack of stations in most regions, contributing to the perception that widespread earthquakes in Arizona are rare. Debunking that myth, a new study published by Arizona State University researchers found nearly 1,000 earthquakes rattling the state over a three-year period.

Jeffrey Lockridge, a graduate student in ASU's School of Earth and and the project's lead researcher, used new seismic data collected as part of the EarthScope project to develop methods to detect and locate small-magnitude earthquakes across the entire state of Arizona. EarthScope's USArray Transportable was deployed within Arizona from April 2006 to March 2009 and provided the first opportunity to examine seismicity on a statewide scale. Its increased sensitivity allowed Lockridge to find almost 1,000 earthquakes during the three-year period, including many in regions of Arizona that were previously thought to be seismically inactive.

"It is significant that we found events in areas where none had been detected before, but not necessarily surprising given the fact that many parts of the state had never been sampled by seismometers prior to the deployment of the EarthScope USArray," says Lockridge. "I expected to find some earthquakes outside of north-central Arizona, where the most and largest events had previously been recorded, just not quite so many in other areas of the state."

One-thousand earthquakes over three years may sound alarmingly high, but the large number of earthquakes detected in the study is a direct result of the improved volume and quality of provided by EarthScope. Ninety-one percent of the earthquakes Lockridge detected in Arizona were "microquakes" with a magnitude of 2.0 or smaller, which are not usually felt by humans. Detecting small-magnitude earthquakes is not only important because some regions experiencing small earthquakes may produce larger earthquakes, but also because geologists use small magnitude earthquakes to map otherwise hidden faults beneath the surface.

Historically, the largest earthquakes and the majority of seismicity recorded within Arizona have been located in an area of north–central Arizona. More recently, a pair of magnitude 4.9 and 5.3 earthquakes occurred in the Cataract Creek area outside of Flagstaff. Earthquakes of magnitude 4.0 or larger also have occurred in other areas of the state, including a magnitude 4.2 earthquake in December 2003 in eastern Arizona and a magnitude 4.9 earthquake near Chino Valley in 1976.

"The wealth of data provided by the EarthScope project is an unprecedented opportunity to detect and locate small-magnitude earthquakes in regions where seismic monitoring (i.e. ) has historically been sparse," explains Lockridge. "Our study is the first to use EarthScope data to build a regional catalog that detects all earthquakes magnitude 1.2 or larger."

His results appear in a paper titled, "Seismicity within Arizona during the Deployment of the EarthScope USArray Transportable Array," published in the August 2012 issue of the Bulletin of the Seismological Society of America. Ramon Arrowsmith and Matt Fouch, professors in ASU's School of Earth and Space Exploration, are Lockridge's dissertation advisors and coauthors on the paper. Fouch is also a geophysicist at the Carnegie Institution's Department of Terrestrial Magnetism in Washington, DC.

"The most surprising result was the degree to which the EarthScope data were able to improve upon existing catalogs generated by regional and national networks. From April 2007 through November 2008, other networks detected only 80 earthquakes within the state, yet over that same time we found 884 earthquakes, or 11 times as many, which is really quite staggering," says Lockridge. "It's one of countless examples of how powerful the EarthScope project is and how much it is improving our ability to study Earth."

Lockridge is also lead author on a study that focuses on a cluster of earthquakes located east of Phoenix, near Theodore Roosevelt Lake. The results from this study will be published in Seismological Research Letters later this year. In his current studies as doctoral student, Lockridge is using the same methods used for Arizona to develop a comprehensive catalog for the Great Basin region in Nevada and western Utah.

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User comments : 32

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julianpenrod
1.6 / 5 (13) Aug 14, 2012
What's the difference between "debunking the myth that earthquakes didn't occur in Arizona" and "earthquakes, previously unknown in Arizona, began to occur and those who don't want the public to know are claiming they are always there"?
And just how possible is it that earthquakes occurring in Arizona before the EarthScope project weren't detected? There were seismic detectors there, just maybe not as many as now! And there were always detectors in neighboring states. The article even mentions that quakes were detected remotely. And an earthquake of magnitude 2 is not a "microquake". Those who want to misrepresent how God is visitng His anger on the world can call it a "microquake", but it isn't.
ryggesogn2
2.3 / 5 (3) Aug 14, 2012
Didn't a major earthquake drive the Santa Cruz river underground?
R2Bacca
4 / 5 (8) Aug 14, 2012
Those who want to misrepresent how God is visitng His anger on the world can call it a "microquake", but it isn't.


Couldn't you have put that at the beginning so I didn't have to waste my time reading the rest of your comment?
antialias_physorg
3.7 / 5 (9) Aug 14, 2012
Those who want to misrepresent how God is visitng His anger on the world can call it a "microquake", but it isn't.

Then god must be awesomely angry at fish for all the underwater seaquakes he causes.
Deathclock
2.8 / 5 (8) Aug 14, 2012
Those who want to misrepresent how God is visitng His anger on the world can call it a "microquake", but it isn't.


Couldn't you have put that at the beginning so I didn't have to waste my time reading the rest of your comment?


But now you know never to waste your time reading JulianPenrod's comments... I've known this for years.
julianpenrod
1.4 / 5 (9) Aug 14, 2012
Among other things, fish don't have houses that get collapsed by ocean bed quakes. For the most part, they float above the ocean bed and what damage they get they can easily repair. And, for that matter, prove there are seaquakes. This article is about supposedly overriding a long held "scientific" belief, based on false observation, that Arizona disn't have quakes, where is antialias physorg's proof that any reports of seaquakes aren't likewise incorrect, thius time claiming there were when there weren't? And, in the end, where is the proof there is not God and this isn't His will? There's a lot of mockery, but that doesn't qualify as proof, even in "science". But, then, antialia physorg's insistence on writing God's name with a lower case "g" is an act of spite, of deliberate disrespect, and you disrespect what you know exists but decide to dislike.
Deathclock
2.7 / 5 (7) Aug 14, 2012
And, for that matter, prove there are seaquakes.


Holy shit... you have to be a troll trying to make Christians look stupid. Tone it down, it's not believable, I don't even think most YEC's are that stupid.
antialias_physorg
3.3 / 5 (10) Aug 14, 2012
where is antialias physorg's proof that any reports of seaquakes aren't likewise incorrect

Yes, yes, yes: We all live in a fantasy world and you are the only one who sees clear (or probably all of us are also just figments of your imagination)

Now go away and grovel a bit more before your priests or whatever else the hell you do in your spare time - and leave the grownups to deal with real problems.

There's a good boy. Now run along...
julianpenrod
1.4 / 5 (10) Aug 14, 2012
Mockery, vulgarity, contempt, viciousness, unjustified dismissal. All chaarcteristic non argument techniques of the New World Order. And explicit prof that those insisting there are seaquakes have absolutely no proof whatsoever that they do.
Deathclock
3 / 5 (8) Aug 14, 2012
You're asking us to prove something that is well established... If you understand any bit of Geology you would understand that earthquakes occur along plate boundaries due to shifting continental plates which shift because they ride on high viscosity molten rock which is subject to convection currents... you would also know that plate boundaries are well established and there are thousands upon thousands of miles of them that run under the ocean... not to mention the fact that we have SEEN seaquakes...

You're asking us to prove something as obvious as the assertion that the world is not flat, that is why we respond with ridicule and dismissal.

You're an idiot.
antialias_physorg
3.5 / 5 (8) Aug 14, 2012
All chaarcteristic non argument techniques

You want arguments. Fine. know what a seismometer is? You doubt that they work? That all seismometers all over the world are rigged specifically to delude you? Really? All of them one big conspiracy (even countries that are currently at war with each other)? That's what you think?
julianpenrod
1 / 5 (7) Aug 14, 2012
The fundamental premise behind "scientific" "truth" is that what "scientists" say can be trusted, that requiring absolute, irrefutable in hand proof is imbecilic. But, in fact, there is no proof provided that what "scientists" say is true because no one has asked! And devotee shills of "science" determinedly work to disabuse the public from the idea not only that they deserve proof but also that "scientists" can lie. "Geologists" say earthquakes form along tectonic boundaries. First, no member of the public has actually touched evidence that earthquakes form along plate boundaries. And even if all the quakes are found to fall along lines, that doesn't mean those are the boundaries of plates. To date, the supposed cause of the "moving" of plates is no more proved than "dark matter". No convection current in the mantle has been observed. And, even if you know how seismometers work, that doesn't mean the "results" they claim are any truer than "election" results.
barakn
3.4 / 5 (5) Aug 15, 2012

But now you know never to waste your time reading JulianPenrod's comments... I've known this for years.

Username:
julianpenrod

Member since:
October 5, 2011, 4:04 pm

Years, huh?
kochevnik
4.7 / 5 (6) Aug 15, 2012
Years, huh?
Feels that way...
antialias_physorg
3.5 / 5 (8) Aug 15, 2012
The fundamental premise behind "scientific" "truth" is that what "scientists" say can be trusted

No. The fundamental premise behind science is that you DO NOT have to trust the scientists. The data is there. It's for anyone to see. The way to get the data is published. You can see whether it's a sensible way or not.
The whole POINT of science (as opposed to anything else) is that the person doing it is unimportant in the process.

(Independent) Repeatability. Falsifiability. Understand these concepts and you have understood what science is and what it isn't.

But, in fact, there is no proof provided that what "scientists" say is true

There is no proof of truth. Ever. (There can be proof that something is FALSE, however - but that is a slightly different matter)
This doesn't mean we cannot know things. It doesn't mean we cannot be very certain that some things are and some things aren't. But if you want to call that 'truth' then you're not talking about science.
Deathclock
1 / 5 (1) Aug 15, 2012

But now you know never to waste your time reading JulianPenrod's comments... I've known this for years.

Username:
julianpenrod

Member since:
October 5, 2011, 4:04 pm

Years, huh?


Oh you think he only has one username huh? You don't pay enough attention.
rubberman
3.7 / 5 (3) Aug 15, 2012
@JP Chemtrail - You believe in an entity that has no material evidence of it's existence. You disbelieve pretty much everything else....seek help, seriously. I don't necessarily trust or believe people until I can verify to my own satisfaction that their claims are valid, however you not only disbelieve the original claim, but also all the evidence that backs it. This is a form of delusional psychosis that doesn't have you ending up in a happy place because either I am right and you end up institutionalized, or you are and we are all doomed to a giant evil conspiracy to eradicate humanity from the globe....cheers!
julianpenrod
1.7 / 5 (6) Aug 15, 2012
antialias physorg is as oblique in talking about "science" as claimte change deniers in their "argument", "It's not climate, it's just weather."
You can talk about reproducibility, but how many people can afford or arrange for their own Michelson-Morley Experiment? Or their own hundred inch reflector telescope? The numbers "scientists" publish are never, ever directly verified in the public's hands. They are proclaimed and shills expect them to be taken at face value. Just because "data is there" doesn't mean it's real and not fabricated! I point this out and devoted obfuscators consistently and determinedly ignore it every time. And as for what "scientists" say being true and antialias physorg's misleading divergence into absolute truth, the "results" "scientists" claim are also claimed to be "true" and is not as open to debate as antialias physorg represents absolute verities to be!
julianpenrod
1.6 / 5 (7) Aug 15, 2012
Just because rubberman wants to claim there is no evidence of chemtrails and their effect on the atmosphere doesn't mean there isn't! I said chemtrail chemicals apparently have been introduced into the air since about 1950 when jets began to be used widely, it's only in 1997 that the air became so saturated that any new chemicals precipitated out. And, note, tornado numbers increased steadily since about 1950 from the relatively constant amount before. And it's not because of more observers. Population has grown only about 2.5 times while the number of tornadoes is about ten times what it was. Too, only two new cloud species were discovered in the recent past, one a few years ago, the last, around 1950, when chemtrailing began. Notice how, in diffidently refusing to accept the real evidence of chemtrails, rubberman engages in what they accuse me of. The evidence that what "science" says cannot be so trusted was always here.
julianpenrod
1.6 / 5 (7) Aug 15, 2012
And note again the commentary of the "legitimacy" of PhysOrg's rating system. I pointed out the demonstrable fact that proof of "science" claims was never really in public hands, only claims of proof. I pointed out the absolute truth that, just because you know how a seismometer works does not mean that the numbers provided you by "scientists" are necessarily true. I indicated the validatable fact that the actual cause of earthquakes claimed at plate boundaries was never observed. And yet, I never received more than 1.4. kochevnik provides only a smirking retort and gets a 5 out of 5. In the end, PhysOrg's system looks more like a popularity contest than anything else, but it looks very much like individual "science" devotees have groups of shills who dutifully give them 5's no matter what they say! And, if Deathclock wants to be perceived as so reliable, what is their proof that I am posting here under other names?
Deathclock
2.6 / 5 (5) Aug 15, 2012
So you do in fact believe in a giant global conspiracy held among tens of thousands of scientists who are nonetheless in direct competition with each other both professionally and politically?

You are a fucking idiot...
antialias_physorg
2.6 / 5 (5) Aug 15, 2012
antialias physorg is as oblique in talking about "science" as claimte change deniers in their "argument"

If you don't believe me what science is then maybe you believe Richard Feynman (one of the most well known scientists. He should know what he's talking about. He also makes it pretty easy to understand)
http://www.youtub...apE-3FRw

If you can't handle that there are no absolutes then that's your problem. The world will not change just because you can't handle reality.

but how many people can afford or arrange for their own Michelson-Morley Experiment?

Go to google. Enter "build michelson interferometer". The first hit should be a PDF which gives you instruction on how to build one for 25 dollars (if it doesn't then add "filetype:pdf").

So to answer your question: Most everyone.
antialias_physorg
2.6 / 5 (5) Aug 15, 2012
For more complex experiments you can actually go and ask the scientists involved. Their email address is included in their publications (if not you can just google their names and institutes and get their addresses that way)

Most will be happy to answer you (if you ask nicely) or at least refer you to the relevant publications so you can check up on it yourself.

Don't expect to be spoon fed. If you ask them how differential equations work and expect them first to teach you how to count then that will probably not happen.

But if you REALLY want to find out what they do and how they work: Go ask.

Scientist are, on average, a pretty laid back, easy-going bunch.
julianpenrod
1.8 / 5 (5) Aug 15, 2012
Deathclock demonstrates how little they have to say, and, therefore, how little legitimacy what they have said has, by their inability to provide anything more than contempt, mockery and vulgarity. What is Deathclock's proof that a conspiracy like that couldn't exist? Especially when so many people are trained not to look behind the curtain? Don't expect anything like a legitimate reply from Deathclock.
Again antialias physorg insists on claiming, without proof, that the way "science" is really carried out is in accordance with the high principles they say they hold to! Just because someone says they are engaging in scrupulous work doesn't mean they are! antialias physorg claims they are maintaining the highest degree of ethic and antialias physorg orders you to believe they are!
And a conventional $25 interferometer will never provide the kind of accuracy sought in determing the change in light speed based on earth's rotation around the sun!
Deathclock
2 / 5 (4) Aug 15, 2012
Deathclock demonstrates how little they have to say ... Don't expect anything like a legitimate reply from Deathclock.


You mean like when I explained to you how plate tectonics work to produce earthquakes?

You're not worth the time.

What is Deathclock's proof that a conspiracy like that couldn't exist?


I don't need to prove that it couldn't exist, YOU need to prove that it DOES exist, or YOU need to STFU about it, because there is no evidence for it.
rubberman
4 / 5 (4) Aug 15, 2012
"Just because rubberman wants to claim there is no evidence of chemtrails and their effect on the atmosphere doesn't mean there isn't!" - JPChemtrail

I didn't say anything about chemtrails other than my admittedly juvenile ad-hoc play on your handle as it was the first rant of yours I remember reading. I said you needed to seek help. My evidence....your posts.

Feel free to retort with 3000 more characters of jibberish.
julianpenrod
1.8 / 5 (5) Aug 15, 2012
Again viciousness and vulgarity from Deathclock. And Deathclock only showed the ability to repeat, not think on their own. Which leaves the issue, too, that Deathclock didn't explain earthquakes, they only provided the doggerel everyone is required to believe. The public do not have in their hands proof that earthquakes occur along "tectonic plate" borders or that they're caused by convection in the mantle. Deathclock can get as angry and vicious and vulgar as they wish, but those are facts.
And the claim, "You have to prove you're side, I don't have to prove mine", is a craven dodge. If someone said there were no giraffes because there were none in their vicinity, "science" devotees would call the method insufficient and say that person failed to prove there are no giraffes. But that doesn't prove there are giraffes! Both sides of an argument must act to prove what they say. If Deathclock respected "science" as much as they claim, they would abide by that.
Deathclock
2.6 / 5 (5) Aug 15, 2012
I can only hope you are trolling, otherwise you have the intellect of a child.

You don't know of or don't respect the concepts of burden of proof or null hypothesis. You don't understand what the scientific method is or how it operates. You don't understand the evidence for or even the most basic information about that which you speak out against... It's pathetic.
julianpenrod
1.8 / 5 (5) Aug 15, 2012
The old story goes about inmates at Bellevue passing notes to each other, saying, "Dr. So-and-so is crazy." Incidentally, the "So-and-so" was the name of specific doctors; New World Order quislings are not above "disproving" my statement by insisintg there never was a doctor name "So-and-so". Just wanting to call someone crazy doesn't make them so. No more than calling truths you don't want heard a "rant". However, it was rubberman themselves who admitted unavailing arrested development action on their part. And rubberman has shown they don't even know how to spell "gibberish".
julianpenrod
1.8 / 5 (5) Aug 15, 2012
In the same way as rubberman, just because Deathclock wants to say I don't understand about the tecniques "science" claims doesn't mean it's true. Deathclock makes the statement that there is no evidence for such a conspiracy. As a statement, that needs to be proved before taken as true, and Deathclock has not proved it. I said there is not evidence in the hands of the public, meaning everyone, not just "scienitsts", that "relativity" is true, that there is such a thing as "evolution" or that earthquakes come from tectonic plate movement. If there is such proof directly, tangibly in the hands of the people, not constituting just proclamations from behind closed "laboratory" doors, then what is it? "Science" only said such things are so but never put into the public's hands actual proof. Deatchclock chooses as their "proof" to ignore that I have demonstrated what I said, a common tactic among those promoting false claims.
antialias_physorg
2.6 / 5 (5) Aug 15, 2012
. As a statement, that needs to be proved before taken as true

The one who makes a statement first must give evidence first.

Otherwise we could just say: You are an alien. You haven't proven otherwise, so it must be true. (and I don't need to corroborate my claim until you prove that you aren't)

See how insane such an argument would be?
rubberman
3.7 / 5 (3) Aug 15, 2012
Thank you for correcting my spelling of gibberish, It is the first time I have ever had to type it. You'll be the most gramatically correct resident at Bellvue, say hi to Doctor Soandso.

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