What’s up with all the earthquakes?

April 15, 2010



This article by Julia Kumari Drapkin originally appeared in Global Post. The views expressed are her own.

The quake that hit China Wednesday was the latest in a string of earthquakes in the news lately. Many people are wondering what’s going on, so we decided to ask NASA. Eric Fielding is a geophysicist who uses satellites to study earthquakes at the Jet Propulsion Laboratories in California.

GlobalPost: So first question is the one on everybody’s mind. What on earth, literally, is going on? What’s up with the earthquakes?

Eric Fielding: The most important thing to remember is there are earthquakes all the time, someplace in the world. In a normal year, there are around 16 earthquakes with magnitudes 7 or higher. So far this year we’ve had six earthquakes like that. So we’re well within the expected range for a three or four month period.

Is there ever a pattern to a series of earthquakes?

There are certainly cases where one area experiences a sequence of earthquakes over time. The most famous and well studied are the sequences that occurred on the North Anatolian Fault in Turkey. The first one was in 1939 and there was a series of seven major earthquakes, the most recent being the 1999 earthquake that destroyed Izmit, Turkey. They were all along the same fault; each one increased the stress on another section of the fault and caused the next section to go. That’s the classic example people use of one earthquake triggering another. There were two earthquakes in 1999, about a month and a half apart.

There was an earthquake that happened in Salta, Argentina, right after the one in Chile. Was that related? The seismic waves would have had to travel through the Andes.

I’d say that was a little further distance than we’d expect. We want to find out more about exactly what happened during that earthquake and how it might be related. We’re hoping to get some radar data from that earthquake but we’re still waiting for the satellites.

There’s a lot of new information to analyze then?

Lately there’s a lot to look at. People like me, who study earthquakes, are getting a little overwhelmed this year. I almost don’t want to turn on the news. But the ones we’ve had this year are more newsworthy. The one in Haiti caused a lot of devastation, the one in Mexico was very close to California. We even felt it here in Los Angeles. The Sumatra earthquake is more expected, they have a magnitude 7 or 8 earthquake every two to three years. The Chile fault line had been identified as overdue for an earthquake and it happened this year.

Are there any lingering questions in your mind with regard to the recent activity? Or do you think it’s completely expected, completely normal?

These earthquakes in general are sort of random — sometimes by chance you’re going to get a coincidence of several earthquakes in a region like the Pacific Rim in a few months. It’s like flipping a coin and getting heads four times in a row. It happens.

Do humans do anything that causes instability or triggers earthquakes?

There are a few cases that we know of where human activity causes small earthquakes – like oil fields where they inject water or steam into the ground to get the oil out more effectively. That can trigger very small earthquakes, on the Richter scale of 1 or 2. Other cases are very large dams where the weight of the water has caused enough stress on the nearby rocks to trigger small earthquakes. But very large earthquakes start at great depths in the earth. And at those depths it’s impossible for humans to have any effect. It’s just too deep in the ground. The Chile earthquake started 40 miles beneath the surface.

What are scientists looking into with regard to ecosystem relationships? How about atmospheric pressures?

There was a recent study published a few months ago that showed that some very small earthquakes in the San Andreas Fault were related to changes and stress due to the tides. The gravity of the moon pulls on the oceans but the solid part of the earth moves up and down by a tiny amount too. You don’t normally detect it with your eye, but sensitive instruments can measure what we call earth tides. Small earthquakes on the San Andreas Fault strongly correlate with these solid earth tides. But that area on the San Andreas has special characteristics. So far we haven’t found that tides correlate to most regular earthquakes.

Is the timing of earthquake activity related to volcanic activity?

Well actually, people are very interested in looking at the volcanoes that are close to the large earthquake in Chile because of Charles Darwin.

Charles Darwin?

Charles Darwin observed the volcanoes erupting in that same part of Chile not long after a large earthquake in 1835. In fact we believe that this year’s earthquake could be a repeat of the earthquake that Charles Darwin observed then. He was on the Beagle and he wrote about it in his book. The observations he made were in exactly the same section of the coast near Concepcion, Chile. He was nearby on the ground at the time of the earthquake. He noted the uplift of the coastline, quite similar to what we observed in the earthquake this year.

And people are looking at the volcanoes near Chile now?

I’m sure the Chileans have people monitoring them on the ground, but there are people studying them remotely, using radar interferometry. We can see that some of the volcanoes have some deformation. People are still working on this so these are still preliminary results.

Last question: What’s the big question? What’s the most important thing that geophysicists like yourself want to know about earthquakes?

The question of how activity on one fault affects activity on nearby faults is one that I’ve been working on for quite a while. The North Anatolian fault in Turkey fits the theory that faults occur in a sequence, but there are lots of places where the faults don’t occur in a sequence. So we’d really like to know more about how that process works. That would give us a much better way to evaluate seismic risk.

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How Saudis really see Americans

Yemen: Where men marry children


Photo shows rescuers searching for victims while local residents stand behind on the rubble of a collapsed building after a 6.9-magnitude earthquake hit Jiegu Town of Yushu County, Qinghai province April 15, 2010. REUTERS/Alfred Jin


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It seems very obvious to me, not sure why others are not seeing That Global warming is melting the ice caps– The weight of the Earth is changing from the caps to the center as the water melts and is sent to the equator because of centrifugal force– The change in weight places different forces on the plates of the Earth– Therefore, many earth quakes!! Beware the month of October– After a very hot summer there will be many quakes to come- one in CA, one in Mexico, one in IL, one in NJ not to mention a huge hurricane and a volcano eruption of our own– I hope to God I am wrong– But Please do all you can to stop global warming!!

Posted by Markriv | Report as abusive

Pretty gloomy prediction…I do not really think global warming is contributing to this trend…Earthquakes are part of life on planet earth…Now is Global warming contributing to extreme storms and climate aberrations such as record highs and lows…absolutely. But you will never get the right wingers in the US to believe it…They have swallowed the propaganda spread by the huge energy companies that make money from fossil fuels and the last thing those companies want are carbon regulations and restrictions.

Posted by RayGunsmess | Report as abusive

there is no such thing as “global warming” and in fact the last decade has seen global cooling despite selective statistics….

perhaps the largest non-random influence on global climate is solar activity….see “The Maunder Minimum”, “Year without a summer”….etc.

although periods of high seismic activity definitely appear related to any observant person, the official “spin” is that they are unrelated coincidences….

if you want to look at possible underlying causes check out what the Earth’s geomagnetic field has been doing under nearly daily disturbances from the Sun…these are solar induced geomagnetic storms that are NOT related to the sunspot activity (which remains abnormally low) and so there is no current means available to predict them.

Posted by EddyCurrent | Report as abusive

Probably, also some seasonal extreme temperature variations can increase the stresses on the crust. The solids, when heated, increase their dimensons. During winter the arctic half is contracting violently, while antarctic is expanding. Every six months the situation reverses. Seasonal temperature differences on the surface of deserts, built areas, or treeless land can be more than 60°C or 120 °F. Trees with their capacity of converting sunrays to clorophill are keeping earth temperatures much more stable. Oceans also have smaller temperature differences than naked or built earth and keep large areas at stable temperature and dimensions. So stress distribution probably could cause some equatorial winter earthquakes like ones of Sumatra or Haiti.

Posted by francok | Report as abusive

Ref Australian Journal Coastal Research 2007 50th special edition by richard mackey. Rhodes Fairbridge predicted all this in his solar inertial motion hypothesis. Sun undergoes inertial motion as it rotates around centre gravity of solar system (Newton 1678). Although sun holds 99% mass of solar system planets hold 98% of angular momentum of solar system. Planets undergo eight characteristic states each average 178.73376 years while sun completes nine loops. Sun is distorted and gravitational and magnetic effects change climate on earth. Fairbridge predicted an increase in earthquakes and volcanic activity in this period. The timing of earthquakes can be predicted. Earthquakes have a relationship with the magnetic Ap index. Ap index is predicted 27 days ahead. Next peak is 4th May 2010, on this date there is a heightened risk of a more severe earthquake. See following webb sites “Solar Cycle 24″, “solar terrestrial activity report”, “Space weather prediction anonymous ftp server” “recent earthquakes world”

Posted by theanswer | Report as abusive

As we approach 12/21/2012, earthquakes, tsunamis and volcanic eruptions will increase in frequency and severity at an alarming rate. This is the result of the unique gravitational pull that is being exerted upon the Earth by the alignment of the planets and our Sun with the galactic center of our universe the Milky Way, creating crustal torque and natural disasters. Watch “Secrets of Alchemy” by Jay Weidner and read Fulcanelli. The double cataclysm is upon us. Prepare or die.

Posted by Xavier920 | Report as abusive

Putting things in perspective, all of the earthquakes in recorded history put together have not wrought half as much damage on humanity as the Western economic system. And at least we have a fighting chance of understanding why earthquakes happen. So, if you had to pick one, I’d say go with earthquakes.

Posted by HBC | Report as abusive

Xavier, that theory sucks, draw a picture.

theanswer, if that is true, submit an article.

An interesting one: Einstein’s ‘glitch’ theory, where sea becomes mountains and mountains sea.

Posted by Ghandiolfini | Report as abusive

The 2012 alignment happens roughly every 25,000 years At the inverted alignment(opposite end of the cycle) a little over 12,000 years ago the last Ice Age ended abruptly coinciding with mass extinctions.

Here is more old ancient religion for you. It is the dawning of the “Age of Aquarius”.

Posted by coyotle | Report as abusive

Gandiodini -I do not post falsehoods.The article already exists, it was given, (Australian Journal Coastal Research 2007 special 50th edition by Richard Mackey)the answer is already there, it is well referenced (120 scientific published papers). There is enough information to search on already to verify what I have printed is true and correct however incredible it may at first appear.

Posted by theanswer | Report as abusive

The randomness of the earthquake has been explained quite clearly by every geophysicist called upon by the media. This is true worldwide.
It is also true that there can be such things as foreshocks, just as there are aftershocks, but the series of earthquakes we are experiencing around the world right now fall into the random category, being completely unrelated to each other. What causes earthquakes is pretty well known, but predicting them seems to be in the realm of Alchemy. Impossible.
Far more interesting is the attempt to forecast volcanic eruptions. Both earthquakes and earth deformities play a part, but what are the other triggers? Some are known, or are speculated knowledgeably. Much is still a mystery.
I place my trust in the knowledge of scientists, not in the hands of misinterpreted ancient calenders. So far this method has worked well for me. I will continue to employ it.

Posted by segue | Report as abusive

segue I agree with what you say about the misguided use of ancient calenders. The information I posted however has nothing to do with ancient calenders but an Article with 120 peer reviewed scientific published papers on a hypothethis by one of Australias most eminent scientists.

Recent evidence of a direct relationship with the AP index does not support your assertion that earthquakes can not be predicted. Starting with the earthquake on 4th May 2010 it will be possible to predict the date of more severe earthquakes up to 27 days ahead using the AP index method from now on.

Posted by theanswer | Report as abusive

The 2012 alignment happens roughly every 25,000 years At the inverted alignment(opposite end of the cycle) a little over 12,000 years ago the last Ice Age ended abruptly coinciding with mass extinctions.

… the dawning of the “Age of Aquarius”.

THAT IS MY POINT..The weight of the Earth is changing from the caps to the center as the water melts.. DURING THE ICE AGE THE WEIGHT WENT TO THE CAPS

Posted by Markriv | Report as abusive

[…] So what’s up with all the earthquakes? Well, not to worry–there are usually about 16 earthquakes each ear above magnitude seven, so we’re still within the normal range. It’s just that they’re being more reported in the news because they’ve hit populated areas and affected more people–and once the news media pick up on the pattern, it’s hard to stop noticing all the quakes. You can be sure they’ll report on all the major quakes in the near future! Read more about this at Reuters.com. […]

Posted by Earthquake update | MS Earth Science | Report as abusive

Kurt Frankel, an assistant professor at the Georgia Institute of Technology, told CNN after the magnitude 8.8 earthquake in Chile on February 27 that there’s nothing unusual going on.

“I’m sticking by my story,” he said Wednesday. “It may be possible there’s been a little bit higher frequency of these slightly larger earthquakes this year, but it’s such a random process that there’s not a connection between them.”……..

After reading this statement. My thought was it is easy to get comments but harder to actually chase down the facts. I would like to see a reference such as a peer reviewed scientific published paper with the information alluded to so as to verify the validity of this statement.
If large earthquakes are so Random then how is it they co-incide with peaks in the Ap index which are published up to 27 days ahead? The existence of the Ap index match does not appear to support the statement made.
I am definately a skeptic and await the 4th May 2010 UTC with renewed invigorated interest.

Posted by theanswer | Report as abusive

A new sun spot group has rotated into view after the sun has had a spotless period of twelve days.

The Ap index is climbing and should meet the 27 day ahead prediction for a peak on the 4th to 5th May.

A high stream coronal hole is predicted to rotate into an earth facing position allowing a proton and electron stream from the sun to be directed towards the earth.

Energy transferred to the Earth’s electric circuit will most likely disturb its magnetic field providing a peak of the A and Kp magnometer readings. Previous peaks in the magnometer readings have co incided with large earth quakes.

Posted by theanswer | Report as abusive