How Earthquakes Are Triggered

[Robert]

The earthquake trigger mechanism is actually a very simple process that can be easily explained with basic High School physics. However, the most important prerequisite for really understanding this process is common sense coupled with an open mind without prejudices. Common sense dictates, for example, that this process cannot be caused by some vague supernatural forces that never really do occur in some form in everyday life. On the other hand, an open mind implies that one cannot always insist on a certain rigid view of the Universe one had once learned in school without making allowances for all the new discoveries that were made in the meantime.

Forces Involved

In order to satisfy the common sense requirement, the simplest analogy of an everyday occurrence to the earthquake trigger mechanism is perhaps a fast car traveling on a winding mountain road. If the car accelerates rapidly, the people in the car are forced backwards into their seats and if the car decelerates rapidly, then the people will be propelled forward — if not restrained by seatbelts. Similarly, if the car makes a fast, tight turn to the left, people seem to get pushed to the right side of the car as their momentum will want them to keep moving in a straight line. And if the car makes a fast, tight turn to the right, they are naturally pushed to the left. But not so a hypothetical ant on the back seat. Because of its negligible momentum resulting from its negligible mass, it barely experiences any “push” and stays put even without seatbelt.

In the case of earthquakes, the phenomenon is similar: As we all know by now from the study of Plate Tectonics (it wasn’t known during my time at university 50 years ago), the crust of the Earth consists of a number of plates which, on their borders where they slide past as well as over or under their neighbouring plates, disintegrate into a jumble of large and small fault blocks (in geology, a "fault" is a break in the rock surface of the solid crust of the Earth), which are separated from each other by differently oriented and earthquake-producing fault planes. Given the same velocity changes (i.e. acceleration, deceleration and “curves”, to use our car analogy), very large masses, such as the just described fault blocks with their huge volumes of rock, are affected to a much higher degree than small masses, like people (or the ant in the car analogy), who can usually barely feel earthquakes of smaller magnitude. This is, of course, a result of the different magnitude of momentum they acquire (or lose) due to their different masses.


Spiral Movements

All astrophysicists agree that a predominant portion of observed galaxies form spirals, so most astrophysicists would agree that this is the predominant path form a star takes when traveling around the center of a galaxy and with it through space. Based on geological and other evidence in the case of our Sun, this round trip is most probably shaped like a Kepler ellipse and lasts between 200 and 300 million years, depending on the different interpretations of individual geologists and astrophysicists.

Some astrophysicists have noticed that there is also an up and down motion, so that the star appears to travel sometimes above the galactic disk and sometimes below it. This implies that superimposed on the spiral path around the galaxy there is also a smaller-amplitude spiral motion around the higher-density center of the galactic arm the Sun belongs to. Again, according to geological and other evidence from differing interpretations, this superimposed motion lasts somewhere between 30 and 70 million years in the case of our Sun. The latest figure from geological evidence seems to point to 62 million years.


Nowadays even elementary school children learn that the planets travel around the Sun in recurring elliptical orbits which, of course, result in even smaller-amplitude spiral paths superimposed on the spiral path of the Sun and lasting, in the case of the Earth, a year. Now add to this path of three superimposed elliptical spirals, that any point on the surface of the Earth travels around the galaxy, the irregularities that are caused by the daily rotation and the seasonal inclinations of the axis of the Earth, and you can see that we all, people and fault blocks alike, are traveling at constantly changing speeds and with constantly changing directions on our journey through space. Just like in a car on a winding mountain road, we all are thus continuously exposed to the various forces these changing speeds and directions produce (with gravity acting as our “seatbelts”) — but presumably we feel these forces only if their magnitudes exceed a certain threshold. Perhaps this is how the unusual animal behaviour before earthquakes can be explained as we know that some life forms have more highly developed sensitivities for particular conditions than others.

Let’s now look at some of those conditions during specific earthquakes: Fig] shows, for example, the probably familiar solar time view of the relationship between the Earth and the Sun, but with a certain twist in it which, incidentally, needs an “open mind” to appreciate. The sketch represents a cross-section through the Earth at the latitude of the largest earthquake ever recorded (magnitude 9.5, Chile, 1960) and also indicates the approximate position of the epicenter at the particular solar time when the earthquake occurred (as shown in blue). The red rectangle indicates therefore the particular region of the crust of the Earth which needs to be examined more closely — as done in Fig.2. The red lines, labeled Fl to F4, are just some of the forces emanating from the Sun and acting on the whole of the Earth.

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Traditionally, Fl, pointed directly at the Sun, is recognized as the only such force connecting us to the Sun, namely the gravitational attraction between our planet and our life-giving star which keeps the Earth in a relatively stable orbit around it. It is also, in absolute magnitude, the centripetal force as well as the centrifugal force that is demonstrated in the classroom as the force on a string tied to an object which we whirl around our heads. The centrifugal force F2 acts, of course, in exactly the opposite direction than Fl and is being used, for example, in a centrifuge that separates the butterfat in the milk from its other constituents. F3, the force pointing to the right on the sketch, is exerted by the momentum of the Earth in its annual revolution around the Sun. However, to understand F4, the force pointing to the left in the sketch, one needs not only somewhat more imagination and common sense, but also a very open mind and the courage to look at things differently than one has been taught in school. Perhaps a slightly unusual analogy from the world of ballroom dancing will help in visualizing this particular force transfer phenomenon.

In contrast to modern dancing styles where partners just sway rhythmically to the music without touching each other, ballroom dancing often requires a tight grip on the partner while twirling at occasionally high speeds (like in a waltz) around the common center of mass situated between the couple. Thus, if looked at from one partner’s perspective, the other partner always has to step in the opposite direction to execute another turn around the mass center. Now imagine yourself standing at the very epicenter of the May 22, 1960 Chile earthquake in the southern hemisphere. At 2:34 in the afternoon local solar time, when the earthquake occurred during their autumn, the Sun stands above the northwestern horizon, going rapidly down and west. So, a fault block located at this site will experience a force pushing it up and east in order to execute this “celestial waltz twirl” around its common mass center within the Sun, as required by implication from Kepler’s Laws.

That this “twirl” force really exists was perhaps proven by the recent discovery of the so-called “fifth force”. However, most of the measurements for this purported “anti-gravity” force were apparently done in the afternoon by the original discoverers and when other people tried to replicate the experiment and made measurements in the morning as well, the phenomenon simply disappeared and therefore the concept was abandoned. Fig. 1 shows quite clearly the reason for this obvious misjudgment. The forces F3 and F4 point, after all, on this solar time graph in exactly opposite directions. For any people whose solar time shows 6 o’clock in the morning, F4, in other words the “fifth force”, merges with the gravitational force of the Earth and thus makes their weight a tiny bit greater (maybe that’s why it’s so hard for some of us to get up in the morning), while at 6 o’clock in the afternoon F4 counteracts gravity at its maximum for the day and we therefore weigh a tiny bit less. At noon and at midnight the two forces presumably act laterally much better, that means earthquakes might more frequently occur on E-W running transform fault, such as occur at the midoceanic spreading ridges.

In any case, 2:34 pm was obviously just the ideal time for the Andes Mountain fault block on the western edge of the South American Plate to be momentarily lifted up and thus facilitate the subduction of the Nasca Plate of the Pacific Ocean under it. Since the plate boundaries there run almost due N-S and therefore the same solar time conditions prevailed over a very large stretch along this boundary, the result was, of course, a very large magnitude earthquake.

As mentioned before, Fig.2 examines the area of the Chile 1960 hypocenter in solar time view a little more closely. The heavy black line represents the crust of the Earth and the thin and short black line shows the position of the main fault separating the two plates at 2:34 p.m. local solar time. The red lines indicate again the direction of the forces Fl to F4. Even though I was never able to make a proper vector analysis for this earthquake because of my totally inadequate computer power, one can perhaps see on this sketch that the dip of the fault plane is almost aligned with the direction of the Fl and F2 forces (centripetal and centrifugal, as well as tidal forces) thus making it a huge region along this dip of temporarily dilating (and therefore prone to cracking) rock. Also, this same dip is almost perpendicular to the F3 and F4 forces (geocentric torque due to annual revolution around the Sun and Sun’s local torque due to daily rotation of the Earth). The magnitude of these torques may have possibly been temporarily enhanced by similar forces emanating from the planets (or we would have a quake there every afternoon), but obviously they were at least temporarily large enough to counteract gravity on the Andes fault block, so that the subducting Nasca Plate was able to slide underneath.

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To generalize, the main temporary “ripping-apart forces” (like the two torques F3 and F4 in the Chile example) have to be approximately perpendicular to the fault plane, as well as large enough to counteract local gravity, in order to trigger an earthquake. And since these forces change from minute to minute, interpolated minute by minute vector analysis have to be made to determine the approximate time when the calculated conditions might permit a shift along the fault plane.

“Variable G” calculations are somewhat easier and faster to make and I remember that I tried them on the Chile earthquake many years ago and determined to my satisfaction that the local G was at that time increasing which facilitated a temporary shrinking of the crust and therefore a subduction zone quake. Similarly, if the local G would be decreasing, the tendency of the crust would be to temporarily expand and this in turn might lead to an earthquake in one of the mid- oceanic or in rift-valley spreading zones. — A note of caution to cosmologists, though: If the “variable G” hypothesis is being accepted and perhaps even proven with irrefutable statistical analysis of these earthquake-based calculations, the presently so very much cherished concepts of the Big Bang, expanding universe, black holes, missing mass, dark energy and many of the other now popular fantastical scenarios (including Einstein’s Theory of Relativity) will prove untenable and fall by the wayside. A much simpler and more plausible picture of the universe will emerge — which may not suit hard-nosed skeptics.

One more note to any seismologists trying to duplicate my efforts in earthquake prediction: In the previous paragraphs I have only mentioned Fl to F4, but there are several other forces as well. In fact, from the three basic parameters I obtain for some celestial bodies (right ascension, declination and distance) from the annually published Nautical Almanac, I calculate about 30 other potential force directions and quite a few dozen functions and function combinations.

Furthermore, all these direction and function calculations have to be done through interpolation down to the minute-level (as mentioned before) to give a reasonably accurate result as shown in Figs. 4 and 5. But even annual graphs can yield startling results as well, as Fig.3 demonstrates. Also, “variable G” calculations could conceivably involve more work then indicated, but I am sure that they would also give even more predictive clues if pursued properly. So be prepared for a lot of work!

Earthquake prediction cannot prevent the destruction of buildings and other infrastructure, but it could certainly minimize large-scale loss of life as well as much of the human suffering associated with such a natural disaster. It is my sincere hope that the governments of the world can be persuaded to provide the funds and facilities needed to combine my method of prediction with the present statistical ones in order to provide a little more security for people living in earthquake zones.

Elfriede Steiner-Grillmair, P.Geol.
Calgary, Alberta., Canada

June 29, 2005

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figure 1




figure 2

The Three Largest Earthquakes in 1986

This graph shows the variation of a simple function of the Sun for the year 1986. It is quite evident that this particular function seems to be one of the determining factors for the magnitude of any earthquake as the 3 largest earthquakes of the year coincide almost exactly with 3 of the peak values of the 6 highest maxima of the year. Obviously, there must have been other important functions involved as well which prevented large earthquakes from happening during the remaining 3 maxima ft is a promising graph, however, more precise vector analysis involving all the major solar system bodies need to be done with high-capacity computers to produce an even better correlation between any particular function combination and the magnitude of any occurring earthquakes.

figure 3

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This series of curves of a particular local function was made for 4 different earthquake locations and shows quite well that the daily rotation of the Earth as well as the annual revolution around the sun affects the occurrence of larger earthquake& The center line in each graph represents the exact time of the earthquake and the other values are all interpolated backwards and forwards from this time.

figure 4

Note especially the 24-hour and 4-minute interpolation graphs. Their striking similarity proves without a doubt that this particular function is dependent on its orientation in space as there is an approximate time difference of 4 minutes between local Earth time and sidereal time.

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As is quite obvious, the form of the curves in the 4 earthquakes is quite different than that of the horizontal component. Again, the center line in each graph represents the exact time of the earthquake and the other values are all interpolated backwards and forwards from this time.

figure 5

Again, note the striking similarity of the first and last series of graphs, proving the dependency of this function on its local orientation in space.

[mkirkpatrick]

Just a brief note of thanks SP,I know what it has cost you to produce this work.

I am very pleased that you have finally managed to publish it here.


warm regards and best wishes,michael.

[Spiral Path]

Thank you for your kind and encouraging words, Michael. They are much appreciated. S.P.

[mkirkpatrick]

You are more than welcome SP,courage and persistence,are the two things needed to
over come the many hurdles that life places before us,determination also goes a long.

I don't know if you heard,but a few days ago in the south-east of England there was a minor
earthquake,a few homes were damaged,one person was injured,these are I believe
quite rare in England.

Would this be the same trigger as in all the others?



warm regards michael.

[Spiral Path]

Yes, Michael, I have heard about the earthquake in England the other day - and yes, these earthquakes are quite rare there and usually of rather small magnitude. Also, yes, they have the same trigger mechanism as larger earthquakes in the rest of the world, only the main extraterrestrial forces at the exact time of the earthquake point in different directions. That's why I can claim that earthquakes can be predicted with appropriate complex calculations if the orientation of the local tectonics are known. Thanks for your questions. Regards, S.P.

[mkirkpatrick]

Manythanks for your prompt reply SP,I have another question for you,I go to Turkey
each year,and am considering buying a house there when I retire in 3 years time,
You have to have earthquake insurance there,as there seems to be a fault system there.


The part of Turkey I plan to go to,is in the MED-just opposite the Greek island of Rhodes.

Is this area really unstable! I would be grateful for your comments.


regards michael.

[Spiral Path]

Sorry, Michael, bad news. Unfortunately the whole region of the eastern Mediterranean is quite unstable. But so is California and millions of people live there quite happily in spite of the constant threat of earthquakes. Of course you have to remember that I look at it in geological terms. In the particular location you have chosen (and I am sure it's a beautiful spot - and probably reasonably affordable), earthquakes may only occur every few hundred or even thousand years (a mere "instant" in the history of the Earth) and chances that one would happen in your lifetime are very slim. So my advice is - go ahead and get your dream place there! But be sure to always pay your earthquake insurance! Also remember - it's usually not the earthquake per se that kills people, it's mostly the buildings they live in, when they collapse! So google on the Internet for modern earthquake-safe building styles and try to get or build one of those. Then relax and enjoy your new-found climatic paradise!

As far as earthquake prediction for this area is concerned - even if my method would be accepted tomorrow and I would get funding for further work immediately as well as have supercomputers and a whole army of seismologists available, it might still be a few decades away until they have decoded the probable earthquake signature for each minor fault in any area - and there are plenty of those in a tectonically very complex region like Turkey. Until then you just have to be fatalistic and enjoy the sun and the sea in spite of the ever present danger - like the Californians do.

Warm regards and best wishes for your retirement dream to come true. S.P.

[mkirkpatrick]

I thank you most kindly SP,I will risk the possibility of an earth shattering experience
and buy a little place in the sun,Turkey is a wonderful country,and a great place to retire to.

I have still got two and a half years to go,not too long!



warmest regards michael.