EARTHQUAKE  TRIGGERING  PROCESSES

Latest  Update:   December 26,  2011

This Web page has been created to serve as a collection and display area
for information related to Earthquake Triggering Processes.


TABLE  OF  CONTENTS

Two Factors Involved With Earthquake Triggering

The Earthquake Triggering Time Equation (EQT)

A List Of Forces Or Phenomena That Might Be
Contributing To Earthquake Triggering Processes

Forces or Phenomena That Might Be Causing Strain To Be
Temporarily or Permanently Added To Earthquake Fault Zones
By Resisting The Movement Of Tectonic Plates Etc.

More Detailed Discussions Of The Above
Two Groups Of Forces Or Phenomena

Other Earthquake Triggering Theories

Earthquake Related Links

TWO  FACTORS  INVOLVED  WITH  EARTHQUAKE  TRIGGERING

       There are at least two factors involved with earthquake triggering.  The first involves the gradual buildup of strain in an earthquake fault zone.  That can take place over time periods as long as thousands of years.  The second factor involves what actually happens within the fault zone to cause the earthquake to occur at the exact time that it occurs.

       Quite a bit is known about that first, strain buildup factor.  However, this Web page creator does not presently know if anyone has proposed what the nature of that second factor might be.  Many researchers probably believe that a small, perhaps microscopic section of the fault zone rock layers snaps under the accumulated strain.  And then there is a rapid cascade of small fractures at that location.  The fracturing quickly spreads resulting in a major failure of a large section of the fault zone, namely, an earthquake.

       Those initial microscopic fractures might result from Solid Earth Tide related bending of the rock layers, strain related sheering, expansion related to heating or chemical changes in that area, a shock wave from another earthquake, or any number of other mechanisms.

       This Web page will focus on discussions of that first, strain buildup factor.  And if any information becomes available regarding that second factor then the plan is to add that information to the Web page.

THE  -  EARTHQUAKE  TRIGGERING  TIME  -  EQUATION  (EQT)

Understanding how strain buildup can cause an
earthquake to occur involves solving the following
Earthquake Triggering Time (EQT) equation:


EQT  =  aA  +  bB  + cC  +  dD  +  eE  ...

          Where:

          EQT   is the actual time of the day, week, month, year, and century when the earthquake is going to occur.

          A, B, C, D, and E ... etc.  are forces etc. that can temporarily or permanently add just enough pressure
                    to the fault zone rock layers to trigger the earthquake.

          a, b, c, d and e ... etc. are factors that indicate how important those different forces are for a given earthquake.

       With most earthquakes, A in that equation would most likely be The Tectonic Plate Movement Related Force.  And a, the importance of that force in the equation would be many times larger than b, c, d, or e etc.

Force A  -  The Tectonic Plate Movement Related Force  -  Most people in the international scientific community probably believe that fault zone rock layer strain force A is already known.  It represents phenomena such as the movement of tectonic plates relative to one another.  Over the ages a given fault zone can store tremendous amounts of strain energy as a consequence of tectonic plate movement.  And eventually, the energy stored in the fault zone can become so great that the fault zone rock layers fracture and abruptly release some or all of their accumulated energy in the form of an earthquake.

       Because that tectonic plate movement related strain storage process takes place over such a long period of time, for many research studies A can probably be regarded as a constant.  And it can be ignored.  An exception to that might be those times when strain is rapidly transferred from one earthquake fault zone area to another after a powerful earthquake occurs in the first fault zone.

       Some earthquakes occur in areas such as in the U.S. New Madrid fault zone where tectonic plate movement is not involved.  And for those earthquakes A might be some other long-term strain building force such as crustal rebound during the centuries when and after tremendous amounts of weight are removed from the fault zone area as a glacier melts.

Sun And Moon Gravity Related Forces  -  My own research indicates to me that the specific, short-term times when many of our powerful earthquakes occur are strongly influenced by forces related to the gravitational pulls of the sun and the moon on the Earth.  Those types of forces add strain to the fault zone rock layers on a temporary basis several times a day, for perhaps an hour or less each time.  And they could be represented by bB, cC, dD, or eE ... etc. in that Earthquake Triggering Time Equation.  The Solid Earth Tide and the Tide-Generating Force appear to be involved.  Ocean tide related forces and even hurricane related forces (ocean water movement related pressure on coastal areas for example) might also be involved.

A  LIST  OF  FORCES  OR  PHENOMENA  THAT  MIGHT  BE
CONTRIBUTING  TO  EARTHQUAKE  TRIGGERING  PROCESSES

       The following is a partial list of the many forces that might temporarily or permanently add enough strain to the rock layers of some fault zone to push it over the edge and cause an earthquake to occur.  Many of these forces have been discussed for years by earthquake researchers around the world.  Some have probably been discussed for centuries.

       Entries in the list have been very roughly arranged according to what the Web page author presently believes might be how quickly they can cause an earthquake to be triggered.  The forces that can act especially fast are towards the top of the list.  Underlined entries are linked to short theory discussions that are listed just below the list.

       There is one particular force that is likely involved with earthquake triggering processes that has not yet been included on this list.  Other researchers are publishing a book that discusses it.  And I am waiting for the book to be formally published before adding the force to the list.  The book authors are proposing that this unusual force generating mechanism is the one that is actually responsible for tectonic plates moving relative to one another.  I myself have not seen that particular, complex force discussed anywhere other than in that new book.

Earthquake related ohmic heating

Earthquake related electric charge repulsion

Earthquake related magnetic material pressure

Physical shock waves from earthquakes, volcanic
eruptions and events such as nuclear tests

Atmospheric storm related air drag

Moon gravity related weight change due to atmosphere tide

Sun gravity related weight change due to atmosphere tide

Moon gravity interactions with the Earth's crust

Sun gravity interactions with the Earth's crust

Internal pressure related to the revolution of the
Earth's core around the sun - Earth - moon center of mass

Ocean tide related water drag

Ocean tide related water weight change

Atmospheric storm related ocean water drag

Strain shift related to earthquakes occurring elsewhere

Temperature related atmosphere weight change

Geomagnetic storm related ohmic heating

Geomagnetic storm related electric charge repulsion

Geomagnetic storm related magnetic material pressure

Solar flare related ohmic heating

Solar flare related electric charge repulsion

Solar flare related magnetic material pressure

Rainwater related effects

Underground magma movement

Polar motion including seasonal wobble and Chandler's wobble

Other planets' gravity related weight change due to atmosphere tide

Other planets' gravity interactions with the Earth's crust

Dam construction related water weight change

Dam construction related fault zone rock layer pore pressure changes

Underground aquifer draining due to irrigation

Water weight shift due to greenhouse effect related glacier melting

Separation type movement of tectonic plates

Parallel movement of tectonic plates relative to one another

Compression type movement of tectonic plates

Water weight shift due to normal glacier melting following an ice age

Localized crustal rebound after glacier melting related weight loss

Localized pressure on the crust resulting from mountain building

Gradual cooling and compression of the Earth

Moon gravity related gradual slowing of the Earth's North - South Pole axis rotation

Sun gravity related gradual slowing of the Earth's North - South Pole axis rotation


THE  FOLLOWING  FORCES  OR  PHENOMENA  MIGHT  BE  CAUSING STRAIN
TO  BE  TEMPORARILY  OR  PERMANENTLY  ADDED  TO  EARTHQUAKE  FAULT
ZONES  BY  RESISTING  THE  MOVEMENT  OF  TECTONIC  PLATES  ETC.

Centrifugal force associated with the Earth's daily rotation on its North and South Pole axis

Earth gravity related pressure for the Earth to assume a sphere shape

Pressure for the Earth to assume an egg shape due to its
rotation around the sun - Earth - moon center of mass

Friction, bending, stretching, and compression processes
associated with the Solid Earth Tide and ocean tides etc.


MORE  DETAILED  EXPLANATIONS  OF  THOSE  FORCES  OR  PHENOMENA

       It should be remembered that many or most of the following are simply theoretical discussions, not established fact.

Earthquake related ohmic heating - Powerful earthquakes can generate strong electromagnetic energy field pulses.  Energy associated with those pulses flows into earthquake fault zones around the world causing their rock layers to quickly heat and expand.

Earthquake related electric charge repulsion - Powerful earthquakes can generate strong electromagnetic energy field pulses.  Energy associated with those pulses flows into earthquake fault zones around the world where it is temporarily stored in the form of ions and polarized molecules which repel one another and cause the fault zone rock layers to quickly expand.

Earthquake related magnetic material pressure - Powerful earthquakes can generate strong electromagnetic energy field pulses which produce temporary changes in the Earth's geomagnetic field.  Magnetic materials in earthquake fault zone rock layers respond to those changes by being pushed or pulled in the same direction or in different directions resulting in earthquake triggering strain being abruptly added to the fault zone rock layers.

Moon gravity interactions with the Earth's crust   (and)
Sun gravity interactions with the Earth's crust  (and)
Other planets' gravity interactions with the Earth's crust - The gravitational pulls of the sun, the moon, and the other planets in our galaxy interact with the rock layers of earthquake fault zones in such a manner that earthquake triggering strain is temporarily added to them in a cyclic manner.  Effects (The Tide-Generating Force) related the moon's gravity are roughly 2.5 times as strong as those of the sun.

OTHER  EARTHQUAKE  TRIGGERING  THEORIES

       Some researchers believe that planetary alignment can have an impact on earthquake triggering.  Some of their theories might propose that gravitational or electromagnetic forces etc. are involved.

Planet Related Gravity Forces  -  This Web page author agrees with many other researchers who believe that effects related to the gravitational pulls of the other planets are likely so weak in comparison with those of the sun and the moon that they can probably be ignored.

       On the other hand, it is conceivable that over a long period of time during the billions of years when the Earth was in its early stages of development, the very weak gravitational pulls of the other planets on the Earth caused some type of earthquake triggering pattern to be built into the structure of the Earth.  And now that the Earth has solidified into its present shape that pattern occasionally expresses itself resulting in an earthquake being triggered.  But in fact it only looks like the other planets' gravity might be involved.

Planet Related Electromagnetic Forces  -  Effects associated with electromagnetic interactions between other planets and the Earth can probably also usually be ignored.  An exception to that might be those times when Mercury or Venus are close to the location of a line drawn between the sun and the Earth.  Those planets might then have an effect on how the solar wind or the sun's electromagnetic field affects the Earth and as a consequence, the triggering times for some earthquakes.

EARTHQUAKE  TRIGGERING

       The following is a detailed theory picture that proposes how earthquakes are being triggered.  Just a few of the most important earthquake triggering forces and phenomena are being discussed in this theory picture.

A - 1   The movement of tectonic plates relative to one another and other processes cause strain to build over centuries in earthquake fault zones around the world.

A - 2   Various obstacles such as the resistance of rock layers to smoothly slip past one another cause that strain energy to build to dangerously high levels in some fault zones.

A - 3   Enough strain eventually accumulates in the fault zone rock layers to overcome those obstacles. And some or all of that stored energy is released in the form of a powerful earthquake.

A - 4   Two groups of forces, phenomena, and factors which can affect earthquake triggering times are ones related to the gravitational pulls of the sun and the moon on the Earth, and fault zone environmental factors such as it north and south or east and west orientation.

A - 5   External forces or phenomena such as atmospheric storm related wind drag on continents and fault zone rock layer heating associated with solar and geomagnetic storms can temporarily or permanently add or subtract sufficient amounts of strain energy to or from the fault zone to move an earthquake occurrence time forward or backwards hours, days, or weeks in time.

A - 6   Forces or phenomena such as shock waves from powerful earthquakes occurring around the world or nuclear tests can produce permanent instabilities in a fault zone and move the earthquake occurrence time forward or backwards days, weeks, months, decades, and even centuries in time.

A - 7   The actual earthquake occurrence time window is often finally determined by strain that is temporarily or permanently added to the fault zone by forces or phenomena which are directly and/or indirectly associated with the gravitational pulls of the sun and the moon. Some of those phenomena would be ocean tides and the Solid Earth Tide.

       The following drawing shows how forces related to the gravitational pulls of the sun and the moon on the Earth's crust can trigger an earthquake. A fault zone running east and west (EW) may fracture when the gravitational pulls of the sun and the moon pull it towards the north and the south at the same time. And a fault zone running north and south (NS) may fracture when the gravitational pulls of the sun and the moon pull it towards the east and the west at the same time.

Fault Zone Environment

A - 8   Two specific earthquake triggering force related theories are presently being considered. The first (see D – 1) involves earthquake triggering pressure being directly exerted on the Earth’s crust by the gravitational pulls of the sun and the moon. The second (see D – 2) involves earthquake triggering pressure being exerted on the crust by the Earth’s solid core as it attempts to move away from the sun – Earth – moon barycenter or center of mass which the core, the crust, the Earth as a whole, and the moon rotate around once each month.

A - 9   When forces or phenomena such as atmospheric and earthquake related shock waves move the earthquake occurrence time forward or backwards in time from when it would have ordinarily occurred then the occurrence time shifts to another distinct time window which is controlled by the gravity related forces. Shifts like that do not involve arbitrary amounts of time.

A - 10   Sun and moon gravity related forces and phenomena can reach high and low strength points in a number of different time cycles. Several of the most important cycles are multiples of roughly 6.25 hours (including 24 hours and 50 minutes) and multiples of about 7 days (including 28 days).

A - 11   A number of cycles having the same time length can be active at a given time. For example, one 6 hour cycle may be controlled by the position of the moon in the sky while at the same time another 6 hour cycle is controlled by the location of ocean tide crests and troughs.

A - 12   Which time cycles control occurrence times for earthquakes in a given fault zone system is strongly related to how forces and phenomena related to the cycles cause different rock layer sections in the fault zone system to be bent, stretched, or compressed in relation to one another. Another way of saying that is to state that what might be described as time cycle controlled Pressure Waves within the Earth's crust are actually triggering most earthquakes.

A - 13   It has been proposed by at least one researcher that in most cases earthquake occurrence times are linked with points of high and low strain in the time cycles while a smaller percentage of earthquake occurrence times are linked with the times when time cycle related earthquake triggering forces are experiencing their most rapid change in strength.

A - 14   Earthquake aftershocks are often not random events as far as their occurrence times are concerned. Those times are frequently controlled in part by those sun and moon gravity related time cycles. In fact, the aftershocks are even more likely to be controlled by them than the original earthquake.


EXTERNAL  VERSUS  INTERNAL  SOURCES  OF  EARTHQUAKE
TRIGGERING  PRESSURE  ON  THE  EARTH'S  CRUST

D - 1   An External Source Of Earthquake Triggering Pressure On The Earth’s Crust

       As the following drawing shows, the Gravity Point is the location on the surface of the Earth where the combined gravitational pulls of the sun and the moon are strongest.

Sun - Earth - Moon Barycenter

       As the Earth rotates each day on its North and South Pole axis, its crust on the side which is rotating towards the Gravity Point is accelerated by the sun and moon gravity while the side moving away from the Gravity Point is decelerated or slowed. That creates strain within the crust. And earthquakes are triggered at locations where that strain causes the crust to be bent, stretched, or compressed in just the right directions.

D - 2   An Internal Source Of Earthquake Triggering Pressure On The Earth’s Crust

       As the above drawing shows, once each month the Earth and the moon rotate around a sun – Earth – moon barycenter or center of mass which is a certain distance down beneath the surface of the Earth. The location of that barycenter is constantly moving towards or away from the center of the Earth depending upon the location of the sun relative to the moon. And because of the larger contribution of the moon gravity to its position, it is always fairly close to the latitude and longitude of the location where a line drawn between the center of the Earth and the center of the moon crosses the surface of the Earth.

       The liquid and solidified iron believed to be the major components of the Earth’s core are roughly 5 times as heavy or dense as the material in the Earth’s crust. As both the core and the crust rotate around that barycenter once each month the mass of the Earth in general attempts to assume the shape of an egg with its ends pointing away from the barycenter. And the solid / liquid core tries to move in a direction almost directly away from both that barycenter and from the location of the moon.

       The Earth’s gravity, rotation, and its somewhat rigid structure prevent it from undergoing rapid, appreciable changes in shape. And its heavy iron core is kept from moving very far within the Earth by those factors. That results in the solid / liquid core exerting earthquake triggering pressure at different locations or pressure points in the crust from inside the Earth. Where those pressure points are located is determined by factors such as the location of center of mass of the core relative to the sun – Earth – moon rotation barycenter and the rotational orientation of the Earth as it revolves once each day on its North and South Pole axis.


EARTHQUAKE RELATED LINKS

       The much older Web page listed below contains some additional important information regarding Earthquake Triggering Processes.  Some of the information on that Web page is scheduled to eventually be added to this present Web page.

Earthquake Triggering Data For 1990 Through 2005, Wave Charts, Earthquake Data Fingerprints

An Extensive Collection Of Earthquake Related Links     An Older Collection of Earthquake Related Links


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