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Chapter II THE TECTONIC STRAIN THEORY AND UFOS
The Tectonic Strain Theory (hereafter referred to as the TST) is a relatively new explanation for the reported appearance of inexplicable luminosities, sometimes UFOs. Papers dealing with certain aspects of the theory have been published in several journals, covering various disciplines (Persinger, 1975, 1976, 1979a, 1979b, 1980a, 1981, 1982, 1983a, 1983b, 1983c, 1983d, 1983e, ). The proposed mechanism is interdisciplinary in nature, and carries with it some necessary qualifications to enable it to cope with a poorly-understood phenomena in terms of better-known phenomena.
The theory is best explained by its major proponent, Michael A. Persinger: "Essentially,...normal geophysical processes applied in unusual space-time configurations are responsible for electromagnetic phenomena that have direct physical and biological consequences. These processes involve normal alterations in tectonic (structural) stresses within the Earth's crust and are mediated by piezoelectric-like effects.
The primary natural analog of this putative phenomena would be earthquake lightning...Whereas earthquake-related luminosities appear contingent upon large releases of structural strain (seismic activities), the luminosities and electromagnetic correlates of alleged close encounters with UFOs are associated with HIGHLY LOCALIZED, less intense changes in crustal structures not necessarily involving major seismic activity." (Persinger, 1979b) (author's emphasis)
The TST draws upon several processes for its mechanism, and it is best to examine each of them in some detail. The physical processes are linked implicitly by logical arguments, although the basis for these arguments needs careful examination. The major steps involved are: 1) Strain is produced in the Earth's crust. 2) Strain produces an electromagnetic discharge. 3A) The electromagnetic discharge produces a luminosity. 4A) The luminosity is observed as a UFO. Alternatively, steps 3A and 4A may be replaced by: 38) The electromagnetic discharge affects human perception. 4B) A person believes that he/she has seen a UFO.
In order to understand the TST, each of these steps will be considered in systematic sequence, in effect testing the links in the chain.
2.1 CRUSTAL STRAIN Through various processes, strain can be built up in the Earth's crust. These include tectonic activity, tidal action and human activity. Strain is described in terms of dilational and distortional strain tensors, as it is a vector in three dimensions (Bath, 1973; Kasahara, 1981; Richter, 1958).
The strain tensor is defined by the equation: [NOTE: In this ASCII version, CX represents the Greek symbol alpha, ^2 means squared, _u represents mu, _[ is the integration symbol, pi is the pi constant, _B is the symbol for beta.] E(i,j) = e(i,j) - (1/3)e(k,k)CX(i,j) and similarly, the stress tensor is: P(i,j) = p(i,j) - (1/3)p(k,k)CX(i,j) where the arrays e(i,j) and p(i,j) each consist of nine component vectors which define the stress and strain across any small plane area containing the point in question. The re- lease of tectonic elastic strain energy is the cause of major earthquakes. This energy can be expressed in a function and form such that: U = _[_[_[_uE^2(i,j) dV where _u is the rigidity modulus (the measurement of the resistance of an elastic solid to shearing deformation) and U is the distortional strain energy, taken through the volume (Bullen, 1963). The stress tensor is defined as: P(i,j) = 2_uE(i,j)
Now, we can also define the stress tensor in terms of the Mises function: P^2(i,j) = (CXS)^2 where S is the value P would have if the material was near the breaking point. CX is a constant that has a value between 0 and 1, and sometimes assigned a value of (sqrt(3))^-1 We can then find E in terms of S such that: E(i,j) = (CXS)/(2_u) we can substitute into our equation for U and find: 4_uU = CX^2S^2Q where Q is the volume of the strained region near breaking point. The total energy released in an earthquake can be roughly calculated by a modified Gutenberg-Richter formula: log E = 11.8 + 1.5 M - 7 - The total energy released in an earthquake of magnitude 8.9 (the greatest on record) is thus about 5 x 10^24 ergs (Bul- len, 1955; Kasahara, 1981). The strain energy, U, will be some fraction of the total energy, E, since there are other forms of energy release such as the dilational strain energy, heat and sound, etc. Thus, we can replace U by qE, where q lies between 0 and 1. Our new equation is then: z_uE = S^2Q where z = 4q (= approximately 2). Experimental results have provided estimates for _u and S: 0.4 x 10^12 dyne cm^-2 < _u < 1.5 x 10^12 dyne cm^-2 S is approximately equal to 10^9 dyne cm^-2
We can then use our equation to calculate Q. The volume of the region near breaking point prior to an earthquake is therefore about 10^19 cm^3, with a radius of about 20 to 50 km in extreme cases (Bullen, 1953, 1955). But this radius is only for the overloaded crustal region. The actual volume of rock in which significant strain exists is obviously much greater than this, but can not be known precisely.
However, reasonable estimates of the size of the total strained region can be made by comparing the distances be- tween earthquake epicentres and precursory effects, indirectly using the magnitudes and energies involved (Brown and Reilinger, 1983).
It is extremely difficult to judge the actual extent of precursory effects, since they will intui- tively vary in type, depth and strength for each earthquake. The determination of the size of the strained region will be discussed further, at a later point in this paper.
2.2 STRAIN-PRODUCED RADIATION There are many types of reported Earthquake precursors on record, including ground deformation, change in the levels and chemistry of well-water and the unusual behavior of animals (Buskirk et al., 1981; Rikitake, 1976; Wyss, 1983). A form of precursor that has received relatively little attention is that of the emission of electromagnetic radiation. Although many such reports are spurious or represent other natural or man-made causes, a significant number are well- documented, and the existence of earthquake-related EM effects must be seriously assessed.
On 31 March, 1980, anomalous EM emissions were recorded thirty minutes before a deep-focus (depth = 480 km) magnitude 7 earthquake 250 km from an observatory near Tokyo (Gokhberg et al., 1982). These emissions were widely-separated at 10 Hz and 81 kHz. Other similar emissions were re- corded for a magnitude 7.4 earthquake in Iran, 1200 km from the epicentre, at 27 kHz and 1.63 MHz. Other examples of such emissions have also been reported (Gokhberg et al., 1980; Sadovskiy et al., 1979). It has been known for some time that the strain loading of rocks and minerals produces electromagnetic emission. The strength of the emission varies with the different types of substances; the strongest emission arises from quartz and other minerals with a high crystal lattice energy, while rocks such as sandstone have a very low ability to produce emission under strain. It has been reported that there is a shift to high frequency with an increase in grain size. The actual mechanism for the production of the emission is not definitely known, although several theories have been pro- posed (Lockner et al., 1983; Mizutani et al., 1976). It has been shown that a rapid drop in the piezoelectric field when stress is released (i.e. when fracturing occurs) can produce EM emission. Experiments have shown that the peak frequency for such a piezoelectric pulse is at about 1.7 kHz, and that the energy release from the fracture of a small rock specimen with a volume of 50^3 cm is about 10^-18 J.
However, there is some doubt that piezoelectricity can produce earthquake lights because of its rapid decay and the possibility of its self-cancelling nature (Finkelstein et al., 1973; King, 1983). An alternate theory for EM emission during fracturing is that of RF (radio frequency) emission caused by a charge buildup across microcracks. During strain processes, there will be discharges between walls of the microcracks which can give not only RF emission, but also IR (infrared) and visible light as well. The energy released by these small cracks has an average spectral range of between 1 and 10^3 MHz (Perel'man and Khatiashvili, 1981). The most plausible proposed mechanism involves the propagation of an elastic wave within rock, following fracture. Demin et al., (1981) have speculated that the wave would induce the growth of microcracks, and, in the case of semiconducting and piezoelectric minerals, the cracking would produce electrical discharges. But the piezoelectric field might also create transistors within the rock, using as barriers the layers of semiconducting minerals occurring naturally in the ore. These transistors could be coupled into circuits, and an EM emission caused by the formation of mi- crocracks could be amplified, in theory, by these piezoelectric and semiconducting minerals. It is immediately obvious - 11 - that in this mechanism the frequency of the amplified EM wave would be dependent on several variables, especially the composition of the rock. This frequency could, depending on these variables, be represented at many points in the EM spectrum, including radio, infrared, visible and x-ray wavelengths. As a point of note, it has been shown that ultra- sonic pulses can also be generated by rock fractures (Demin et al., 1981).
2.3 LUMINOSITY FROM ELECTROMAGNETIC DISCHARGE As was mentioned in section 3.2, EM emission by rock fracture will probably also include visible wavelengths. The actual size of the luminosities thus produced is difficult to ascertain. While luminescence has been reported in the literature, this has only been in the form of "comet tails" and sporadic outbursts detected on photographic film in close proximity to the rock outcrop undergoing fracture. However, it has been claimed that small, luminous bodies have been detected on the film of the fracturing of a core sample in the laboratory (Brady, private communication).
{1} __________ {1} A description of the experimental conditions under which the luminosities were observed is given by Brady et al (unpub).
These bodies have the reported appearance of sparks caused by the impact of rocks upon one another, but are believed to be fracture- and not impact-related. It has been suggested that if the processes which produce EM emission during rock failure are scale invariant, then in nature, luminosities will be produced by the strain and fracture of large or bod- ies beneath the Earth's surface (Brady et al., (unpub)). These luminosities produced outside the laboratory will, it is thought, be much larger than those observed in the laboratory, perhaps reaching 1 m or more on diameter.
2.4 UFOS AS FRACTURE-RELATED LUMINOSITIES If it is indeed possible that large luminosities can be produced in nature by crustal stress, then it would seem likely that they would have been observed and reported. Many reports of seemingly inexplicable lights in the sky have been made throughout history, many given the name "UFO" by default (Jacobs, 1976). But there do exist rare, natural phenomena that appear as lights in the night sky.
These include ball lightning and earthquake lights, both of which are still not fully understood by scientists, but progress is being made in unravelling their mysteries (e.g. Charman, 1979). In general, earthquake lights are luminous hemispheres, 20 to 200 m in diameter, with a duration following an earth- quake of 10 seconds to 2 minutes. In addition, radio interference is reported to occur after the luminescence, strong- est at about 15 kHz, which is an order of magnitude from the peak emission for strain release under laboratory conditions (Derr, 1973,1977; Finkelstein and Powell, 1970).
It has been suggested that the release of stress before an earthquake could generate large electric potentials, creating fields of 10^5 V/m (Demin et al., 1981). If rocks can possess a high enough resistivity (about 10^9 ohm - m), then earthquake lights might be explainable in this manner (Gokh- berg et al., 1980). Ball lightning has been reported infrequently, but enough cases are on record that some characteristics have been determined (Barry, 1968). It is spherical, with a diameter of about 30 cm, and may have a contained energy of 10^3 to 10^7 J (with an average of about 10^5 J) and an energy density be- tween 10^2 and 10^3 J cm^-3. - 14 -
2.5 ELECTROMAGNETIC EFFECTS ON THE HUMAN SYSTEM Rather than creating a physical luminosity through the production of visible photons, an alternate method to produce a UFO in the TST is the direct effect of EM radiation upon the human brain. It has long been understood that both electric and magnetic fields affect physiological systems in various ways. Effects range from dizziness and irritation in weak fields to severe disruptive effects such as induced epilepsy in strong fields. Basically, it appears that the electrochemical responses within the body are interfered with by external fields, causing the confusion of signals received and originating from the brain. Experimental tests have shown that headaches are frequently reported by individuals ex- posed to electric fields of 15-25 kV/m for extended periods of time (Sheppard and Eisenbud, 1977).
As well, fatigue and sleepiness are also reported to be symptoms of prolonged exposure to electric fields, although other studies fail to support this, possibly due to differing experimental conditions. Medical examinations of individuals exposed to electric fields have found changes in blood composition and cardiovascular function (Persinger, 1973). Since the human body behaves as a conductor, external electric fields will be internally attenuated except in the upper-layers of the skin.
The perception of electric and magnetic fields by human beings has been a topic of interest for many years. Electric fields of 50-60 Hz, of >10 kV/m can be consciously detected by humans, probably by the erection of body hairs. Weaker fields of 100 Gauss and at frequencies between 10 and 100 Hz, an individual will observe flashes of light. The peak frequency for this effect is at about 20 Hz. Whether this has any bearing on the reporting of UFOs is not known (Sheppard and Eisenbud, 1977). __________ {2} Because of the potential danger in exposure to EM radiation, limits were recently proposed for the maximum recommended level of human irradiation (Cahill, 1983).
2.6 TEMPORAL LOBE EXPERIENCES Under extreme conditions, it has been speculated that at high voltages, individuals might experience rather severe alterations in normal brain functions (Persinger, 1983c). "Dreamy conditions" and temporary paralysis might be experienced. Other suggested sensations are out-of-the-body experiences (OOBEs), religious "awakenings" and feelings of "cosmic significance", since these emotions can be produced by stimulating the limbic structures of the brain (including the hippocampus) with electric currents. Such stimulation apparently may induce "false" memories of dreamed events, making a person "believe" he or she has experienced some- thing which has not occurred. These "artificial hallucinations" would seem "real" to the individual thus influenced. In this way, the "bizarre" aspects of UFO experiences such as seeing an alien entity, conversing with it, etc., might be explained in terms of an interference in brain functions (Persinger, 1983e). The stimulation of the temporal lobe is perhaps the most interesting of all the effects noted. This stimulation could produce disorientation and epileptic-like experiences that might include actual seizures and loss of consciousness. Upon recovery, the individual might well have amnesia regarding certain parts of his or her experience, all due to electrical interference within the brain (Persinger, 1979b). - 18 - The suggestion is that the behavior of the individuals is not unusual in any way. Rather, it is the interpretation of the experiences which is unusual, and thus, the UFO phenomenon can be reduced to a poor interpretation of the experiences of individuals who have actually been in contact with geophysical electromagnetic emissions. However, the reasons for the consistent description of such experiences in terms of UFOs are not elaborated upon in the TST.
The TST includes some consideration of the separation be- tween the observer and the geophysical luminosity. At a distance, only the optical effects would be reported. As a per- son approached the emission, it would have increasingly greater effect upon the human system, until finally, in the event an actual physical contact was made, the unfortunate individual might be electrocuted, and death would be attributed by an unsuspecting coroner to lightning or contact with power lines (Persinger, 1979b).