Physics/2 Physics of a firm body

D.f. TH н. Urusova B.I., асп. Mamchueva F.M., Umarova M. H.

Karachaevo - Circassian state university, Russia

The physical nature of return magnetisation of mountain ores

The purpose of the given work is research of the physical nature of return magnetisation of mountain ores (gabbroid), rivers Maryhi taken from a left bank, Zelenchuksky area, Karachaevo - Circassian republic, number of a borehole 8/1021 and age .

The character, therefore natural magnetisation has a magnetic field dipole corresponds to a direction of a vector of the geomagnetic field, existing during formation mountain ores.

In mountain ore (gabbroid) it is possible to explain occurrence of return magnetisation two hypotheses: 1) the magnetisation self-reference; 2) inversion of a geomagnetic field. From the first hypothesis follows, that return magnetisation communication is connected physics - chemical the processes caused by magnetisation of mountain ore (gabbroid) against a direction of a geomagnetic field. And from a hypothesis of inversion of a geomagnetic field follows, that a principal cause of occurrence of return magnetisation is existence in time of formation of mountain ore (gabbroid) the magnetic field of the Earth which had a direction return existing. That assumes numerous inversions of a magnetic field of the Earth. However, this statement it is insolvent, in view of the magnetisation self-reference.

On Neel [1], thermoresidual magnetisation of saturation - , can change the direction at temperature passage through critical points.

Knowing the mechanism of processes of the self-reference of magnetisation that is: the mechanism operating in homogeneous magnetic systems and mechanisms characteristic for diverse magnetic systems and according to theory Нееля follows, that in the first group the basic role is played by negative exchange interaction of knots А-В sublattice whereas interactions А-А and В-В can be both positive, and negative.

Then, a resultant spontaneous magnetisation is a difference of magnetisations caused by two sublattices A and B:

(1)

Where - at heats and at low temperatures where there is a self-reference.

Change cationing distributions in sublattices A and B in the course of cooling of magnetic mountain ore (gabbroid) at heats and after its cooling can be the reason of distinctions in temperature dependences .

In two-and multiphase magnetic systems self-reference mechanisms sublattice can be divided on magnetostatics and exchange between phases through their border.

Calculations have shown, that at small distances between grains A and B is observed magnetostatics the mechanism. For this purpose, a necessary condition is non-simultaneous magnetisation of grains of different phases of mountain ore (gabbroid).

Exchange interaction in diphasic system is possible only at cristallography continuity of phases, presence of the general oxygen layers. Thus the self-reference can occur, if , and, the greatest effect is observed, when a phase A - weak ferromagnetic, and a phase B - ferromagnetic.

The literature:

1. Neel L. Some theoretical aspects of rock magnetism.//adv.phys.1955.V.4. №14.P.191-243.