Beyond Earthquake Lights: Progress in Seismo-EM
By Alberto Enriquez, Free-lance Journalist. Posted Jan. 23rd, 2008; Updated Jan. 29th, 2008
Extraterrestrials–or down to earth EQL?
A Canadian couple fishing Tagish Lake, Yukon Territory snapped seven glowing orbs in the 1970s. Angler Jim Conacher estimated the orbs to be 4 feet wide. Nearby orbs drifted up the mountain joining the others. Though the snapshot is popular with ET fans, down-to-earth facts about its setting are worth noting. The entire region is noted for continual seismicity. Quakes sometimes generate aftershocks for months.
Earthquake lights have been seen up to 100 km from quakes. Because EQL are caused by rising stress in rock, they may even precede a "silent quake," i.e. a fault sliding without a shock. EQL are only one possible effect of rising stress, others include infrared and radio. (Photo by Jim Conacher, courtesy John Derr)
Cast largely beyond the pale of American geology, seismo-electromagnetics has emerged in recent years as a vibrant new branch of earth science. Its theoretical underpinnings are secured by experimental confirmation in both field and lab. Its burgeoning observational base–thousands of unambiguous correlations of electromagnetic signals to geologic faults under severe stress–now lies beyond rational dispute.
The earth, quite simply, is electric.
What's more, it's now clear that the earth telegraphs its most damaging motions in advance. The frontier of this new scientific discipline is no longer debate about the reality of pre-earthquake signals. Rather, the focus in several nations is upon the accelerating race to deliver practical earthquake prediction. The question of "whether" prediction will be possible is rapidly being whittled down to a question of "when." The United States is by no means out of this race, but developments worldwide have amassed impressive depth and breadth:
The United States has no dedicated seismo-electromagnetic program on par with France. Instead, NASA has sheltered parts of the young discipline through ad-hoc programs of lab experiments and satellite analysis, piggybacked on other programs or borrowing essential equipment during down-time. For instance, the Ouzounov and Bryant studies scan IR satellite images produced for weather forecasting. The mature remote sensing technology takes on a vivid new dimension when one sees how brightly infrared emissions delineate known faults in the days before a quake!
Emergence of a peer-reviewed specialty journal often signifies that moment when a new discipline enters the mainstream. Elsevier already has proposed such a journal. For now, principal researchers in seismo-electromagnetics are continuing to reach out to other earth science and physics specialists by publishing in more comprehensive journals. Even so, Elsevier's 2006 “Physics and Chemistry of the Earth” special issue remains a must read for any layperson or professional interested in the field.
An "impossible" dogma
Clearly–with these kinds of investments of time, talent and money–we're not talking cold fusion! Seismo-electromagnetics has arrived. Like many an overnight success, it's been long coming. Just six years ago, it was difficult for a reporter to pry the word "prediction" from the lips of even optimistic researchers. After all, powerful American seismologists, working inside and outside the United States, had declared prediction "impossible." Some went so far as to accuse other nations of misappropriating U.N. funds spent on EM precursor research. The vitriol of these accusations was born of bitter experience. In the '70s, preliminary studies led many geophysicists to believe that traditional seismological techniques could be refined to provide practical short-term earthquake prediction. Congress duly approved funding for the US Geological Survey to develop "earthquake prediction systems," but the traditionalists were soon disappointed by the failure of seismology to predict quakes. Professionally embarrassed at having over-promised and under-delivered, some turned against anybody who dared to continue precursor research, even those outside seismology.
All types of earthquake prediction research were tarred with the same brush. Although a baffling panoply of EM precursors has been reported all over the world since ancient times–and scientifically documented in Japan, China and Italy by the 1960s–American research into these highly suggestive natural phenomena virtually dried up by the early '80s. Seismology traditionalists ruled the roost on the peer review committees that control funding and publication. To this day, the USGS (notwithstanding its congressional imperative to explore prediction under Public Law 108-360) has consistently refused to fund research into the most promising precursor theory–semiconductor effects within the earth's crust.
The full "inside baseball" story of these intervening decades is not for an article of this scope. Suffice to say it's a classic tale of the failure of scientific skepticism. It's not a failure to be sufficiently skeptical of an extraordinary claim. Many claims made by precursor researchers are well founded in observation and experiment. Rather, it has been the failure by many American scientists to skeptically examine an untested– indeed untestable–dogma: "Earthquakes cannot be predicted."
Working in the face of neglect and even condemnation from mainstream seismologists, two men of exceptional perseverance deserve special mention for the rapid progress now being made: Dr. Friedemann Freund, of NASA-Ames, and Dr. Masashi Hayakawa, of the University of Electro-Communications, in Tokyo.
A swiftly semiconducting planet
Incredibly, Freund was ready by the late 1970s to articulate an essential insight that led eventually to a new semiconductor theory of the earth's crust. A solid-state physicist, Freund was focused on ceramics, when he realized that the dehydration/crystallization reaction which forms all non-sedimentary rock also creates dormant "positive hole pairs." Holes have long been a commonplace term of semiconductor theory. Plainly stated, holes are virtual particles capable of transmitting an electronic charge. Rock is normally a strong insulator. However, when these dormant positive holes are activated in rock under stress, the holes act as positive charge carriers. They pass through rock almost as easily as an electron passes through a metal wire. The effect of these charges (phase velocity) is transmitted at a maximum speed of 200±50 meter per second. This is an actual lab measurement closely matching the theoretical calculation.
Working in relative obscurity, Freund developed the necessary lab techniques to track the charge propagation and to perform other essential measurements needed to confirm his findings. Competing theories exist to explain earthquake precursors, but only the semiconductor theory has led to successful replication of EM and IR precursors in the lab. Did the world of geology beat a path to his doorstep? Not hardly.
"Geology journals weren't interested because it was semiconductor physics," Freund says. "And physics journals weren't interested–because it was geology."
Finding signals–winning friends
Halfway round the globe, Hayakawa championed an open-minded examination of the evidence. Beginning in the mid-90s, he directed two major Japanese "frontiers" in seismo-electromagnetic research. Through these well-funded frontiers (RIFKEN and NASDA), Hayakawa and his collaborators dominated field observation of electro-magnetic earthquake precursors. They were first to pinpoint quake-related ULF emissions from the earth's crust. They were first to conclusively tie pre-seismic events to subsequent ionospheric disturbances which, in turn, interfere with VLF radio.
No less important, Hayakawa promoted robust international discussion. When traditionalists within the USGS and American academia were dismissing research by Freund and others, Hayakawa's four symposia provided an amicable forum welcoming "pre-earthquakers" from all nations. When even Japanese funding for earthquake prediction research softened under the relentless barrage of criticism from American traditionalists, Hayakawa's resolve never buckled.
"The only possible response we had to take was to intensify our efforts," Hayakawa wrote following the termination of the RIFKEN and NASDA frontiers.
Not surprisingly, over the past two decades, most key papers on field observation of seismo-electromagnetic effects were written by Japanese scientists. Many of the remainder came from Russian scientists collaborating with their Japanese counterparts.
Making a battery of stone
Neither man has rested on past achievements. Early in 2005, Freund made an astonishing discovery. He'd long demonstrated that dormant positive holes in rock are activated by heat, destructive crushing pressure, or sudden bullet-like shocks. The biggest surprise came after he started treating rocks more gently. Freund found that when clamped under moderate pressure, rocks could act as a battery. Without any additional pressure, a rock held in the vise would sustain a picoampere current for up to 24 hours! Moderate, nondestructive pressure triggered the wholly unexpected sustained current of positive holes.
Picoamps (trillionths of an ampere) from a small slab of rock held in a vise may seem trivial. Yet multiplied by the vast cubic-kilometers of stressed rock near a fault, the potential current is immense. Totaling millions of amperes, it is ample to power all the EM precursors seen in nature. These include infrared anomalies, VLF radio interference, ionospheric disturbances, and geophysical luminosities. Geophysical luminosities include outbursts of light from the ground, known as "earthquake lights," as photographed at Matsushiro during the earthquake swarms of the 1960s. They can also include free-floating plasmas. In 1999, these hauntingly beautiful orbs were videotaped for months before a killer quake hit Izmit, Turkey. These and other electromagnetic effects may explain some UFO sightings or reports of supernatural illuminations at ancient sites ranging from Buddhist shrines in China to Christian pilgrimage sites in Europe.
Significantly, in the lab such stress-induced electric currents flow without the need to fracture or micro- fracture the rock. This suggests why EM precursors can arise days and weeks before a quake. Seismology captures the catastrophic (and truly unpredictable) mechanical output of the system as a fault breaks free. By contrast, seismo-electromagnetics captures the effects that arise during the continuous build-up of stress in the rocks around the fault at an earlier, non-catastrophic stage, much more amenable to analysis and prediction.
The positive hole current discovered by Freund indeed flows from the stressed rock as from a battery–but a "battery" based on solid-state physics not chemistry. No chemicals are consumed. The current shuts down when the vise is released. It spikes to same initial level each time the pressure is reapplied. Clamping and releasing many times causes no loss of "charging capacity." A moment's reflection suggests that this indefinitely rechargeable capacity should be no surprise. After all, any rock in the Earth’s crust has endured countless stress episodes underground before being cut into a lab sample.
Hearing Sumatra's earliest cry
Hayakawa's most recent VLF and ULF studies are no less compelling. Hayakawa's group has characterized the evolution of natural ULF signals emerging from below the earth's surface. His group also has studied seismic interference with man-made VLF radio broadcasts. In particular, they have examined when these changes may be expected. His network has detected ULF signals preceding earthquakes from shallow to mid depths, but for unknown reasons, not from deep quakes. Within his network, these signals are detected only from quakes exceeding 5.5 magnitude, and reliably so, when magnitudes reach or exceed 6. Range appears to increase with quake magnitude. Although the Sumatra quake lay far outside Hayakawa's network, strong fluctuations in the VLF were noted from five days before the quake struck on Dec. 26, 2004 and continuing for seven days after. The titanic scale of the Sumatra quake (~9.3) may have contributed to the long-distance detection, Hayakawa says.
Hayakawa's precursor studies dovetail with a critical aspect of Freund's semiconductor theory. Hayakawa has detected signals up to one week before a seismic event. This would seem to be consistent with the view that non-destructive stress is sufficient to initiate EM effects.
Some EM effects, like infrared emissions commence soon after non-isometric stresses reach moderate pressures. In the lab, positive holes stream freely to the surface, generating IR effects. Arrival of these positive charge carriers at the earth's surface also can affect the ionosphere in ways that interfere with manmade VLF radio.
However, in Freund's semiconductor theory of the earth's crust, the positive hole currents that generate natural ULF radio emissions deep in the earth must follow a more circuitous route. Consequently, ULF effect should be seen only before more powerful quakes.
How the Earth builds a radio
Positive holes flee a stressed rock volume wherever they are activated. They can stream freely to the earth's surface and collect at peaks and other areas of high curvature, creating IR and visible corona. But the physics of holes strands negative charges at the boundary between stressed and unstressed rock. They cannot follow. Within the earth's crust, there exists an upper zone, which permits p-type conductivity (positive holes). This zone is normally separated from a lower zone, which permits n-type conductivity (virtual electrons, or negative holes). Under normal stresses, the two zones do not interact.
Freund's theory states that if the volume of severely stressed rock continues to grow, stressed rock eventually makes contact from the p-type zone down to the n-type zone. Immediately, two oppositely charged currents pour out of the stressed rock volume. Positive holes stream into the p-type zone. Electrons stream into the n-type zone. Some distance away from the fault, holes and electrons discover a path to recombination, completing a vast underground circuit. In Freund's view, this cycling of very high currents–potentially on the order of hundreds of millions of amperes–generates the low to extremely low frequency "radio" broadcasts deep within the earth's crust. On this point, Hayakawa's field observations and Freund's theory concur. It takes major stress to switch on a radio this big.
Fine-tuning pre-seismic signals
Hayakawa believes characterization of EM effects around specific faults will require prolonged study. For example, infrared anomalies in continental China seem to arise and evolve somewhat differently than in island Japan. Nonetheless, he is confident that EM studies will provide useful earthquake prediction in the range of weeks and hours. For a variety of reasons, Hayakawa says VLF monitoring may be the most promising technique. VLF handily skirts a difficulty that dogs IR observation of the world's most seismically active nation: frequent heavy cloud cover obscuring the island chain.
To the Moon and beyond
Ongoing EM research extends far beyond life-saving earthquake predictions. Freund's semiconductor theory may also have implications ranging from solving the mystery of electro-deposition of gold, silver and copper veins within the Earth's crust, to explaining the ring magnetization recorded around some lunar craters, and understanding the synthesis of organics associated with the grains that waft through the galaxy in huge interstellar dust clouds. Practical applications have led NASA to quietly explore a variety of patents.
Perhaps it's time that Congress revisited Public Law 108?
More information on recent progress in seismo-electromagnetics
Hayakawa ground-based networks
French/Demeter satellite observations
About the Author
Alberto Enriquez is a freelance writer living in Medford, Oregon. He has written for publications including MUSE, a children's magazine; New Scientist; and Spectrum, the journal of the IEEE. He has also worked as a technical writer-illustrator, and has won awards for spot news, editorial, feature and science writing–as well as poetry. Enriquez first wrote about "earthquake lights," earthquake prediction, and the research of physicist Friedemann Freund in January 2002, while working as a reporter for the Anchorage Daily News. A New Scientist cover story followed in July 2003. More recently, he discussed the application of Freund's theories to a privately-funded quake detection network in California. "Early Warning for Earthquakes," appeared in the February 2007 issue of Spectrum.
© Copyright 2008 NMSR and Alberto Enriquez, All Rights Reserved