Geology And Geophysics

Cascading Earthquakes and the Theory of Global Rupture

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"Cascading Earthquakes and the Theory of Global Rupture"
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What if a super-quake set off other super-quakes around the world in a cascading cacophony of catastrophe?

Since the mega-thrust quake that struck northeastern Japan during March 2011, that question is on the lips of many.

Clusters of earthquake cascades

Some researchers believe that non-local earthquake cascades occur in clusters and point to graphs depicting energy release versus time. They argue that the charts don't lie and the numbers prove that historically most of the energy released by major earthquakes results in several very large quakes globally—a chain of destructive dominoes collapsing one upon the other.

Observers, familiar with the theory, immediately turned their focus to a long overdue region that sits within the so called "ring of fire"—a zone that follows the perimeter of the Pacific rim where the Earth's gigantic tectonic plates sometimes brutally collide with each other.

Could quakes like the Japanese 9.1 magnitude really precipitate a worldwide calamity of biblical proportions?

Geological evidence from the past proves it has happened—and what once was will be again.

The P- and S-waves

Where tectonic plates meet they create and destroy the crust.

Although the energy released creates life, it can also mercilessly crush out life. The Sumatra 9.3 magnitude earthquake and tsunami snuffed out the lives of some 300,000 people and the Japanese 9.1 quake and tsunami may have killed 25,000 or more.
According to some theorists, cascading quakes are triggered by great quakes. The trigger may be the initial waves of intense energy that are released. one of the two types of seismic waves is suspected of causing cascading.

The first wave is known as a “P” or "primary wave." It releases an explosive burst of titanic pressure that propagates through the crust.

The second wave, called the “S” or "secondary wave" creates a turbulent horizontal shaking called shearing.

The P-wave is thought to be a triggering mechanism that can travel through the mantle and trigger other faults if it's carrying enough energy in the wave. Although the S-wave causes most of an earthquake's destruction locally, the P-wave may well be the initiator of cascades nearby and perhaps globally as well.

Currently, the theory of cascading is accepted by most seismologists, geophysicists, and geologists. The cascade theory of fault rupture argues a quake has a tendency to spread across one part of a fault to a neighboring fault rupturing the crust like a crack spreading on thin ice.

Ideally, all earthquake activity ceases when the energy that produced the rupture ceases.

While there is a high degree of statistical correlation between the P-wave's initial propagation of wave and the earthquake's final magnitude, there is little hard data (other than anecdotal) to support the P-wave as a triggering mechanism causal to cascading quakes occurring within hours or days at other far flung locations across the Earth.

The ringing bell hypothesis assumes that the high energy waves—slamming into already weakened faults—act like the initial high explosive charge that triggers a hydrogen bomb explosion.

Henry Feilding Reid and elastic rebound

After the 1906 San Francisco earthquake, American geophysicist Henry Feilding Reid measured the displacement of the ground surfaces in the region of the San Andreas Fault.

His calculations led him to believe the deadly quake was caused by an "elastic rebound" of stored elastic tensions building up a vast store of available energy in the tectonic plates facing each other on the fault line.

Today, Global Positioning Satellite technology confirms Reid’s theory.

The P-wave and elastic rebound may help initiate global cascading quakes, but what actually "pulls the trigger?"

Underground lightning, telluric currents and quartz

Earth is like a gigantic capacitor. The planet can be charged and discharged by rotating external electric fields that are in a state of flux.

The phenomenon of subterranean lightning traveling through huge deposits of quartz along earthquake fault lines may trigger higher magnitude quakes. The P-wave would excite the quartz along certain frequencies creating a cascading lightning storm underground. Those electrical thunderbolts would in turn cause some already weakened tectonic plates to buckle, fold and shear.

The P-waves may also interact with telluric currents. The currents are generated by both natural and artificial interaction with the geomagnetic field.

The currents are related to—and influenced by—the earth's magnetic field. They are linked to atmospheric lightning and to subterranean episodes of lightning discharge, or underground lightning storms.

Geophysicists have found that a low frequency window appears when the currents travel through the substrata of earth. When that occurs the planet acts as a conductor and resonates thousands of amperes of raw energy.

A recent study conducted by two geophysicists—Utah State University's Anthony Lowry and his colleague at the University of London, Marta Perez-Gussiny—found evidence that the mineral quartz may hold the key to earthquake triggers.

The two scientists determined that quartz deposits are found in areas of the earth with weakened crust. Such geological hot spots are highly likely to generate earthquakes.

The telltale mineral was present along mountain ranges and tectonic fault lines.

Calling the discovery of the strong correlation between fault lines and quartz "eye-popping," Lowry and Perez-Gussinye show how the mineral soaks up and stores water. They explain how all the water suddenly escapes when the quartz is subjected to intense pressure. That release of water permits the rocks comprising the earth's faults to slide, break free, thrust and shear.

Lowry calls the process a "viscous cycle."

But what "intense pressure" causes the explosive release of energy from the quartz? Subterranean thunderstorms and sometimes the stimuli of P-waves propagated by other great quakes elsewhere on the planet.

Interacting with the P-waves, the Earth's magnetic field, and the complex charges in the mantle, crust and ionosphere, massive electrical energy is generated and thrust through huge deposits of quartz triggering major or great quakes.

With great enough intensity, the Earth can shake loose mountains and cities and people like a big dog shaking off fleas.

More about this author: Terrence Aym

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