The classic models of kimberlite eruption include explosive-boring volcanism, fluidization, and hydrovolcanism briefly reviewed in (Mitchell, 1986). All the models have both positive and negative features. Source of explosion energy is one ot the most important problem discussed.
We present here new constraints to physical model of kimberlite formation based on a theory of physical vacuum. The kimberlite pipes are considered as a intrusion of vacuum domain (VD) into the lithosphere. The problems of intrusion, movement and explosion of VD in the Earth crust are solved using a model of non-homogenous physical vacuum (NPV) (Dmitriev, Dyatlov, 1996). NPV as a localized space volume, is described via a model of macroscopic electrogravidynamics (Dyatlov, 1995). The explosion model considers quasi-statical case and establishes deep-seated field interaction between VD and solid rocks, which takes into account a partial time derivative. Well known electric and magnetic field equations in quasi-static approximation, where time delay caused by electric wave propagation is equal to 0, are also used. Macroscopic electrogravidymamics deal not only with an electric waves length but also with a length of gravispin waves. Studied in this model portion of space includes VD body and its nearest neighbourhood. In quasi-static approximation (Dmitriev, Dyatlov, 1998), the problems of electric field and electric current and problems of magnetic field and electric current are divided. Besides, problems of electric gravitation and problems of magnetospinorics are also separated.
Main problems of deep-seated explosion of VD are solved using our methodologies and groups of equations in electric gravitation and magnetospinorics. General postulates of VD theory may be considered as following:
where V is VD volume, a( is electrogravitational coupling constant (a((1), (o=1.161 kg/K, ((=-a((o-1(G is density of coupled polarization electric charge, (G- air density (1293 kg/ì3). The electric field on VD surface is described by equation:
E=((([R/(3(o)], (2)
where R is a radius of VD sphere, (o=8.85(10-12F/m. E=-4,18 - -4,18(103
V/m, if R=1-1000 m, and a(=1. Thus, VD in the atmosphere has weak electric
mono-charge and insufficient electric field, which is not enough to produce
electric sparkover of air, and accompanied depolarization is practically
negligible. It explains durable existence of VD in the atmosphere.
4. VD depolarization in the lithosphere (first 10-15 km) speeds
up steeply due to changes in density and physical state of matter. According
to (1), electric mono-charge rises in factor of 3-4 comparing with its
magnitude in air, if (G=103-104 êã/ì3. VD depolarization
in the lithosphere is accounted for by electric conduction current.
The density of heat power are connected with density of conductive
current within and outside of VD as:
PT=JE=Jr2/(, (3)
where ( is specific resistance. Extracted heat power within VD is
PTi=[4(((2]/[9(5(T2](e (-2t/T)R5, (4)
extracted heat power outside of VD (in nearest neighbourhood) is
PTe=[4(((2]/[9(T2](e(-2t/T)R5, (5)
combined heat power is
PT=PTi+PTe=[2(4(((2]/[3(5(T2](e(-2t/T)R5, (6)
Energy of VD contact with electric conductive rock derived from equations (4-6) is
WT= o(( PTdt=[((2R2]/[5((o{1-a(2/(}](V, (7)
where V=4(R3/3 is a volume of VD sphere, ( has complex physical means
but its most simple explanation is a electrogravitational coupling parameter.
(>0 for positive VD, (<0 for negative VD.
Using Maxwell equations for rate of relaxation, a depolarization
in geological-geophysics media occurs in regime of explosive energy emission
WT, i.e. «contact» explosion takes place. This explosion has
energy density described as
WT=WT/V=[((2R2]/[5((o{1-a(2/(}]. (8)
From (8) the explosion energy is proportional to radius of VD sphere
and has magnitude near 106J/m3, if R=1km. During a field trip to Altay
mountains, one of the authors observed the VD sphere 8 km in diameter (Dmitriev
et al., 1992). Hence, if such a sphere would produce «contact»
explosion in shallow lithosphere, the energy emission would be expected
near 8x1015J.
5. Specifics of «contact» explosion, where an explosive
has field nature and is found within crystal structure of rocks, must be
taken into account. This is specific micro-explosive with snap-action pulse
heat production and electromagnetic radiation (characteric time is 10-8c)
. It does not shift a matter but transforms it within explosion conduit
in situ due to physical-chemical state of matter and in heat and high-power
vortixes. We emphasize self-localized nature of «contact» explosion
that produce minimal changes in neighbouring rocks. If we consider positive
and negative VD varieties, we can expect abundant diversities of «contact»
explosion actions both in kinematic features, and in physical-chemical
transformations. Another specific features of «contact» explosion
is its multistage development, which is determined by VD transportation
where movement is developed in magnetic and spin field. Explosion condition
is depended on VD depolarization intensity changes. During depolarization
main explosion force is produced by gravitation field. Explosion and its
sequences have well-defined space localization.
The mathematical model of NPV is a new direction in physics (Dmitriev,
Dyatlov, 1998). Their «contact» explosion equations have to
play an important role in geological processes. The effect of «contact»
explosion in the lithosphere can explain such phenomena as a coexistence
of high grade and low grade metamorphic rocks with sharp contact in the
Earth crust, or some surface processes.
We suppose that «contact» explosion theory may be applied
to explain the formation of kimberlite pipes. VD very sensitive to activity
of faults of ancient dikes. Reactivation of deep faults during kimberlite
intrusion from the depth cause VD intrusion from above. Thus, VD explosion
in shallow lithosphere can accompanies kimberlite eruptions and would be
important source of explosion energy, due to colossal power effect with
inexpected action. Moreover, VD can originate and exist not only in the
atmosphere and nearest space, but also in the lithosphere or in the mantle.
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Geophysics, and Mineralogy SB RAS Publ., 212p. (In Russian).
Dmitriev, A.N., and Dyatlov, V.L., 1996, A model of non-homogeneous
physical vacuum and natural self-luminous formations: IICA Transact., Novosibirsk,
v.3, p.65-76 (In Russian).
Dmitriev, A.N., and Dyatlov, V.L., 1998, Planetophysical function
of non-homogeneous physical vacuum: Inst. of Mathematics SB RAS Publ.,
, 377p. (prep., in Russian with English abstract).
Dyatlov, V.L., 1995, Linear equation of macroscopic electrogravidynamics:
NSA, MITPF, preprint 111, Moscow, 24p. (In Russian).
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Plenum Press, NW, 1986, 442p.