Quakes and fakes

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By Donald Prothero, Occidental College

As many of us watch the horrors of the nonstop news coverage from Japan, a lot of misinformation seems to be sweeping through the media and the blogosphere. Since I’m a geologist trained in seismology, and also the author of the new book Catastrophes: Earthquakes, Tsunamis, Tornadoes, and other Earth-Shattering Disasters (Johns Hopkins University Press), I’ve been asked to write up a brief summary of the fact and myths about the earthquake.

First, the basics. The March 11, 2011, Sendai quake, which occurred at 2:46 in the afternoon local time, lasted almost 5 minutes in terms of total shaking. Its epicenter (38.322°N 142.369°E) was about 130 km (81 mi) east of the Oshika Peninsula, near Sendai, on the main island of Honshu. Its moment magnitude (Mw, a modification of the Richter scale used for largest earthquakes) was reported at 8.9 9.0, making it the largest in Japanese history (which has had at least 6 other quakes greater than Mw 8.0 since 1896, and millions of smaller quakes), and the fifth largest quake in world history since the invention of the seismograph. (The largest is the Mw 9.5 Chile quake in 1960, followed by the Mw 9.2 quake in 1964 in Alaska, the Mw 9.1 quake in Sumatra that caused the great Indian Ocean tsunami, and a Mw 9.0 in Russia in 1952; the quake in Chile last year was a Mw 9.8 8.8, just slightly smaller). Some sources place the magnitude of the Sendai quake at Mw 9.0 or 9.1, which would tie it for fourth largest in history.

Like all earthquakes in Japan and most of the countries on the west Pacific rim of the “Ring of Fire,” it was produced in a subduction zone, where one tectonic plate (the Pacific plate) is sliding down beneath another plate (the Eurasian plate). The plates are not sliding smoothly, but grinding past one another at an oblique angle, so a lot of friction and stress builds up over a long time until it is released in huge earthquakes. The rupture zone is reported to be about 480 km (300 mi) long undersea, and 200 km (120 mi) wide, and the overlying plate is reported to have uplifted as much as 10 m (30 ft) once the stress was released (similar to what happened in Alaska in 1964) (see here for some interesting plots). The shaking was so extreme that the upward force on the people and objects was about 0.3 times the acceleration of gravity. Since the initial event, there were over 600 Mw 6.0 aftershocks in the first 24 hours, and thousands of smaller ones, and the area is still feeling them more than 48 hours later.

Tsunami. Ever since consciousness-raising of the 2004 Sumatran disaster, people have gradually stopped mislabeling seismic sea waves as “tidal waves” (since tides are not involved in these waves, which are generated by earthquakes, volcanoes, or landslides). Now they refer to them by their proper name “tsunami,” which means “harbor wave” in Japan, a country that has experienced many of them over the past centuries. As we saw in the Indian Ocean in 2004 and again in Sendai, a tsunami is a wave with very long wavelength generated by a sudden displacement of water in the ocean (earthquake, volcanic eruption, giant submarine landslide). On the open ocean, it is a barely perceptible swell that most boats don’t notice. When it reaches shallow water and the wave base intersects the bottom, however, it turns into a huge wall of water that sweeps a long way inland, then withdraws dramatically (exposing the intertidal and subtidal zone), then may come back with even longer waves every few minutes. The reports of the Sendai tsunamis are that the waves crested at 10 m (33 ft), and washed 10 km (6 mi) inland. If you saw footage of the area on TV, they often showed these huge waves carrying boats, cars, airplanes and other debris far inland or sweeping them out to sea, and advancing across the flat farmland around Sendai in an unstoppable wall of water. Thanks to the excellent earthquake-resistant construction of most buildings in Japan, relatively few people were killed by building collapse. Instead, far more victims (the count is still unknown) were killed by the tsunami.

Prediction. After any major earthquake, there are always people asking why geologists didn’t predict the quake. Actually, this quake had been predicted as long overdue, since it was in a “seismic gap,” a part of a known fault zone that has fewer than the expected number of quakes and is thought to be building up stress for a big one. But what most people want is a short-term warning that allows them to evacuate and seek shelter. The Japanese have hundreds of seismographs in place, so they were able to issue warnings about a minute before the quake, although that would not have made much difference to people who were too close to the quake to find protection in less than a minute. That’s about as good as we can expect in terms of a short-term warning. Seismologists have been seeking the “holy grail” of short-term earthquake prediction for decades, but without much luck. After some spectacular successes and failures in the 1970s with the dilatancy model, most seismologists now realize that earthquakes have many different causes and behaviors. Some appear to have precursors, while others have none whatsoever. Thus, geologists have become more and more cautious over the decades that we will ever be able to predict most earthquakes except over the very long term. If you hear some psychic or astrologer say otherwise, it’s a fake. As Charles Richter himself said, “Only fools, charlatans, and liars predict earthquakes.”

Are we seeing more big quakes than normal? This is another question buzzing over the Internet and the media. With our short attention spans, it sure seems like the events in Japan, Haiti, New Zealand and Chile add up to a lot more than average. However, if you do the statistics carefully, the quakes of this past few years are about normal for a given period of time. In any given year, we average about three huge quakes worldwide that are bigger than Mw 6.0 or greater, and thousands of smaller ones; earthquakes are happening every second somewhere around the world. And if we look over enough decades, we see that this current crop of big events is not even the biggest in the past 50 years. The 1960s, with the biggest earthquake on record (1960 Chile) and the second biggest (1964 Alaska), had far more giant quakes than we have had in the past decade.

The myth probably arises because we have short memory spans, and most of us were not even born then, let alone adults paying attention the news in 1960 or 1964. In addition, we now have worldwide instant media coverage of a big quake, especially those in countries like Japan where there are cameras everywhere. By contrast, there was almost no film coverage of the 1960 disaster in southern Chile, and only a few films were made of the 1964 Alaska quake. Most people learned of those quakes by the newspaper days later, and saw little or no film footage on TV.

The “supermoon” theory. The media are buzzing with the predictions of an astrologer who claims that this quake was caused by the unusual perigee (closest point of its orbit) of the moon (the “supermoon”) on March 19, when it will be closer than it has been in 18 years. But this, like all of astrology, is pure garbage. As Hank Campbell, Steve Shimmrich, Phil Plait and others have pointed out in their blogs, the “supermoon” idea is ridiculous. The Sendai quake happened on March 11, a week too early, when the moon was nowhere near perigee. Likewise, it is absurd to link the moon’s perigee to last month’s quake in New Zealand. That time framework is ridiculously broad, so that ANY event occurring anywhere near the “supermoon” of March 19 could be claimed to be related. In fact the moon reaches perigee every 29.5 days, and none of the other perigees over the past few decades can be statistically associated with earthquakes, either, or any of the many “supermoons” of the past 30 years. Finally, the physics of the situation rules the “supermoon” prediction impossible. The distance is only 15 km closer for an object over 360,000 km away, so the difference between the gravitational attraction on March 19 and any other perigee of the moon is minuscule. It will make higher and lower tides than a normal full moon, but it has no effect whatsoever on something more massive like the earth’s crust.

All this attempt to stir up a media frenzy and put out crazy notions about supermoons affecting earthquakes, volcanoes, and weather is pure bunk (see Phil Plait’s links on the topic. Those who do so are trying to get free media attention, since the media these days can’t tell what is news and what is garbage. They are relying on our usual psychological blind spots of “confirmation bias” (remember the hits, forget the misses) and “correlation does not equal causation” to get people to buy into their crazy ideas and garner attention. And when, after March 19, nothing really happens, no one will go back to these astrologers and demand an explanation for their failures.

And of course, nothing brings out the “end of the world” crazies like a big earthquake. As always, this kind of talk is purely in the realm of religion and supernaturalism, not science.

63 Comments

And for sheer stupidity, it’s hard to top AiG’s “explanation.”

Mike Elzinga said:

And for sheer stupidity, it’s hard to top AiG’s “explanation.”

I don’t know whether to say that it’s stupid, or just heartless, evil and malicious to explain handwave natural disasters as being one of the prices for original sin.

“the quake in Chile last year was a Mw 9.8, just slightly smaller”

I think you meant to type “8.8”.

Good read - thanks!

It’s fairly bog-standard fundamentalist theology that Adam’s sin in some way knocked all of creation a-kilter; thus we have not only human evil and sickness, but also natural disaster. I believe the proof-text is Romans 18:20&ff.

Link to Steve Shimmrich actually goes to the excellent post by Callan Bentley.

burk said:

“the quake in Chile last year was a Mw 9.8, just slightly smaller”

I think you meant to type “8.8”.

Good read - thanks!

Yes, sorry–that’s what happens when you write an essay in a hurry after almost no sleep, and nobody around to proofread it before you send it. At least this is an obvious typo that anyone can correct using the context.… Off to bed–gotta wake up at 3:30 a.m. PDT to catch my ride to the studio for a 5:10 a.m. taping about the quake on MSNBC…

For every natural disaster that occurs, there are a billion religious nuts who try to ascribe some theological importance to the event. Plate tectonics, people! Mindless religious rationalizations trivialize the anguish and the deaths of the victims.

I heard on the evening abc news of 3/12/11 that the earth’s orbit was slightly affected by the quake. Nonsense. The earth’s rotation around it’s axis was slightly changed, but that has happened before and will again. The earth going around the sun was in no way impacted by this/these quakes. Unfortunate that the news can’t get their science correct.

FYI. Here’s a handy website where you can track earthquakes worldwide. You can zoom in to any particular area (not real close however) and also get details about the quake/s. If you zoom in on the area of Japan you’ll see an incredible number of quakes/shocks that have taken place. http://earthquake.usgs.gov/earthqua[…]d=world.html

thanks for the review, Donald.

Always a pleasure.

DavidK said:

FYI. Here’s a handy website where you can track earthquakes worldwide. You can zoom in to any particular area (not real close however) and also get details about the quake/s. If you zoom in on the area of Japan you’ll see an incredible number of quakes/shocks that have taken place. http://earthquake.usgs.gov/earthqua[…]d=world.html

This is called IRIS, and is also an excellent resource.

http://www.iris.edu/seismon/

It amazes me that there are still people who believe that there is a supernatural reason for earthquake and other natural disasters ie: floods, tsunamis, hurricanes, tornadoes, volcanoes etc.

Can any one answer this question. On March 5th Kilauea eruptive intensity increased. 2 new eruption sites occurred along a rift zone. On going eruptions increased in intensity and flow. After the quake on March 10th. all the erupting stopped, Kaputt. Obviously Hawaii is in the mid Pacific plate. Could these event be connected or it this coincidence? Here is a link to the eruption page at the USGS http://volcanoes.usgs.gov/hvo/activ[…]eastatus.php

God, if he exists, is a bastard- easy observation without all the mind bending illogical gymnastics. Now lets get back to understanding the science, and helping people in need. We can do that because we are caring humans; we don’t need a God variable to justify it.

Now, getting back to my aid work.

Great post Don. Thanks for writing it.

Straightpoint said:

God, if he exists, is a bastard- easy observation without all the mind bending illogical gymnastics. Now lets get back to understanding the science, and helping people in need. We can do that because we are caring humans; we don’t need a God variable to justify it.

Now, getting back to my aid work.

Exactly - either God caused it to happen, or allowed it to happen. These are the only two possibilities if you are invoking an omnipotent entity. As Dawkins said about Pope John Paul II, why didn’t God cause the bullet to miss him entirely?

And once again the fundamentalist evangelical atheists are blaming God, who they don’t believe in, for all the evil in the world. It’s just an earthquake, okay? It’s a fleeting temporal event with no effect on eternal souls. The real question is how to help the survivors and get the infrastructure moving again so they can make a quick recovery.

And for sheer stupidity, it’s hard to top AiG’s “explanation.”

Clearly Mike, there was no such a thing as plate tectonics prior to the fall !

mplavcan said:

DavidK said:

FYI. Here’s a handy website where you can track earthquakes worldwide. … http://earthquake.usgs.gov/earthqua[…]d=world.html

This is called IRIS, and is also an excellent resource.

http://www.iris.edu/seismon/

Here’s the one we use in California: http://earthquake.usgs.gov/earthqua[…]a_Nevada.php

Claude said:

And once again the fundamentalist evangelical atheists are blaming God, who they don’t believe in, for all the evil in the world. It’s just an earthquake, okay? It’s a fleeting temporal event with no effect on eternal souls. The real question is how to help the survivors and get the infrastructure moving again so they can make a quick recovery.

So if this “fleeting temporal event” had the effect of the death of your children and your whole family on you, then your (and your family’s) eternal soul would be untouched??? Mine (after of course dealing with the situation at hand), had I been a believer in God, would be doomed cause I would either try to avenge the destruction by striking at God or stop believing in her. But then again I live in reality most of the time and not only when it doesn’t conflict with my world-view;I don’t choose to evoke it only when it’s in the interest of my belief system…

Is God willing to prevent evil, but not able? Then he is not omnipotent. Is he able, but not willing? Then he is malevolent. Is he both able and willing? Then whence cometh evil? Is he neither able nor willing? Then why call him God?

P.S. If you were being sarcastic ok,sorry;mea culpa…

P.S.2 Egad ,how viral these memes can get!In my language and country (Greece) the first mutant copy that I have bumped onto is that the vice president of the Russian Academy of Sciences (allegedly named Arcady Tishkov,haven’t ckecked if the name matches) has allegedly said that the earthquake was caused by the moon and by solar eruptions.That it has even gone global so that the world leaders are preparing for a global catastrophe in 2012.They’ve even managed to relate it to our greek favourite Angela Merkel (not very popular at the present time in Greece due to matters of economy…) ,ordering a thorough check of Germany’s nuclear facilities in preparation for world events… :)

Thanatos said: P.S.2 Egad ,how viral these memes can get!In my language and country (Greece) the first mutant copy that I have bumped onto is that the vice president of the Russian Academy of Sciences (allegedly named Arcady Tishkov,haven’t ckecked if the name matches) has allegedly said that the earthquake was caused by the moon and by solar eruptions.

Japan’s most devastating earthquake in the country’s history may have been provoked by the position of the Moon and the processes that are under way on the Sun. The opinion was ventured in an interview with the Voice of Russia by a Russian researcher, Deputy Director of the Russian Academy of Sciences’ Institute of Geography Arcady Tishkov.

The ignorance continues at http://english.ruvr.ru/2011/03/12/47299635.html

And then there’s “OBSERVATION OF A YETI IN THE HIMALAYAS OF TIBET By Professor Arkady Tishkov” at http://www.bigfootencounters.com/bi[…]/tishkov.htm

Arcady (or Arkady) may not be wearing enough aluminum foil in his hat…

Paul Burnett said:

Thanatos said: P.S.2 Egad ,how viral these memes can get!In my language and country (Greece) the first mutant copy that I have bumped onto is that the vice president of the Russian Academy of Sciences (allegedly named Arcady Tishkov,haven’t ckecked if the name matches) has allegedly said that the earthquake was caused by the moon and by solar eruptions.

Japan’s most devastating earthquake in the country’s history may have been provoked by the position of the Moon and the processes that are under way on the Sun. The opinion was ventured in an interview with the Voice of Russia by a Russian researcher, Deputy Director of the Russian Academy of Sciences’ Institute of Geography Arcady Tishkov.

The ignorance continues at http://english.ruvr.ru/2011/03/12/47299635.html

And then there’s “OBSERVATION OF A YETI IN THE HIMALAYAS OF TIBET By Professor Arkady Tishkov” at http://www.bigfootencounters.com/bi[…]/tishkov.htm

Arcady (or Arkady) may not be wearing enough aluminum foil in his hat…

The greek version has already Arcady promoted to Vice President(or anyway deputy director,translation varies) of the Academy of Sciences instead of the Voice of Russia’s version of him being Deputy Director of the Russian Academy of Sciences’ Institute of Geography. Man it would be very funny and interesting to read if only one had the resources and time to go through and recreate the whole evolutionary tree and path of the meme… :D

Link to Steve Shimmrich actually goes to the excellent post by Callan Bentley.

Indeed it does; thanks! I do not know which one Professor Prothero intended, but the link to Steve Shimmrich is here.

DavidK said:

I heard on the evening abc news of 3/12/11 that the earth’s orbit was slightly affected by the quake. Nonsense. The earth’s rotation around it’s axis was slightly changed, but that has happened before and will again. The earth going around the sun was in no way impacted by this/these quakes. Unfortunate that the news can’t get their science correct.

What I read said that the calculated effect of the earthquake was to change the length of the day by about 1.6 microseconds and to move the poles by about 10 centimeters. I would like to hear if there is experimental verification of such changes. This is sometimes brought up as an argument against geocentrism, but I would not like it to be used if there is no observation of the effect.

Claude -

And once again the fundamentalist evangelical atheists are blaming God, who they don’t believe in, for all the evil in the world.

Obviously not. What happened was that religious fundamentalists claimed that god caused the earthquake as punishment for sins, and that claim was referenced here. Also, the “problem of evil”, that is to say, the question of why an omnipotent and omniscient god allows this type of suffering, is a well-accepted theological issue.

It’s just an earthquake, okay? It’s a fleeting temporal event with no effect on eternal souls.

That certainly seems to be a remark at odds with the teachings of the Biblical character Jesus and mainstream Christian theology. I’m not religious, but I don’t have to be to notice this.

The real question is how to help the survivors and get the infrastructure moving again so they can make a quick recovery.

From my perspective, this is true.

However, if I were trying to maintain a belief in an omnipotent, omniscient, omni-benevolent god, other questions, related to that belief, would occur.

I’m not saying that they can’t be answered by subtle theologians, and I have no problem with religious belief that doesn’t try to violate my rights or mislead the general public about science. But the questions are certainly there.

Tsunami, harbor wave, is not an entirely satisfactory term either. Especially with the international warning graphic, also from Japan, which shows a gigantic storm wave. While earthquake caused waves can be focused and heightened in a harbor, they can likewise be lessened. And much of Japan devastrated by this Tsunami were in fact in open coastland, and not harbors.

Oh well, language is always ambiguous, and often inexact. The metaphor of a Tsunami as temporarily raising sealevel in a succession of waves lasting up to several hours does have some tidal aspects to it, as opposed to a series of storm waves. It is its own thing, and does vary greatly from place to place.

And once again the fundamentalist evangelical atheists are blaming God, who they don’t believe in, for all the evil in the world. It’s just an earthquake, okay? It’s a fleeting temporal event with no effect on eternal souls. The real question is how to help the survivors and get the infrastructure moving again so they can make a quick recovery.

“I’ll take: Out of Left Field for a thousand, Alex.”

TomS said:

What I read said that the calculated effect of the earthquake was to change the length of the day by about 1.6 microseconds and to move the poles by about 10 centimeters.

So here’s a question… 10 centimeters is measurable these days via commonly used surveying tools.

When the earth’s poles move, what happens to all the various property lines?

I know that my property deed is defined in relative terms back to some datum the county uses. My deed says something like “the eastern 65 feet of the western 100 feet of plot 6 of parcel 21”, and such language is, in my experience, fairly typical and harks back to the days when surveying was an approximate art.

But now that survey people are using GPS tools, my last property deed also includes absolute references - latitude and longitude numbers.

And eventually, even relative terms, like “10 feet of plot X” have to wrap back to some absolute reference, like a USGS geodetic marker, which essentially defines local latitude and longitude.

I know that the magnetic poles move a little every year. I used to live in a place where I had to buy updated marine charts every few years because they moved enough to matter.

When the magnetic poles move we simply add in a reference offset and lat/lon grid stays the same.

But when the physical axis moves, what happens? Do we add an offset, or do we redefine the entire lat/lon grid to keep lined up on the axis?

Did my fence just legally jump 2 inches into my neighbors yard?

TomS said:

DavidK said:

I heard on the evening abc news of 3/12/11 that the earth’s orbit was slightly affected by the quake. Nonsense. The earth’s rotation around it’s axis was slightly changed, but that has happened before and will again. The earth going around the sun was in no way impacted by this/these quakes. Unfortunate that the news can’t get their science correct.

What I read said that the calculated effect of the earthquake was to change the length of the day by about 1.6 microseconds and to move the poles by about 10 centimeters. I would like to hear if there is experimental verification of such changes. This is sometimes brought up as an argument against geocentrism, but I would not like it to be used if there is no observation of the effect.

Kenneth Hudnut, a geophysicist with the U.S. Geological Survey reported on CNN that it appears that main island of Japan moved by 8 feet (2.4 meters). Sort of kills Walt Browns popular “hydroplate theory” of the Nochian flood. Do you think maybe Noah noticed his Ark capsizing with the resulting tsunami?

I get it .

Tsunamis are the result of Adam’s scrumping.

Others were not punished like that for my scrumping

Don’t blame it on religion. It’s politics, pure and simple. As an economist, I have seen the same media phenomenon where absolute rubbish is published as economic fact in order to garner political support and power. The charlatans predicting earthquakes are of the same order,political hustlers using both pseudo-science and pseudo-religion to lead the lost into the woods, as Jesus put it.

Mike Elzinga said: Well-designed nuclear power plants can look pretty good until viewed against the backdrop of the evolutionary histories of both humans and the Earth.

That history of humans involving at unpredictable intervals Murphy’s Law.

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