LOCAL GEOMAGNETIC FIELD CHANGES AND SEISMICITY OF ARMENIA FOR ۱۹۸۱-۱۹۹۳

On the territory of Armenia the network of geomagnetic observatories is created with allows to measure the variations of components D, H and Z of Earth's magnetic field The data of stations Jradzor, Garni and Tavuch (۳۰ km, ۱۵۰ km and ۲۰۰ km from epicenter of Spitak earthquake of ۰۷,۱۲.۱۹۸۸ y.) for time period ۱۹۸۶-۱۹۹۳ years are used in analysis. From these data the ratio of amplitudes A of variation of each component of the magnetic field sinchronously measered by each pair of stations (parameter N(A)) is obtained for periods of variations ۵-۲۵ min, ۳۰-۶۰ min and ۵-۱۰ hours. From the begining of observations up to moment of Spitak earthquake the trend in the behavionr of N(A) is observed for all ۳ components ۰, II,Z and for all periods of variations. On the background of trend the sharp changes of N(A) are observed during two intervals: from March to July of ۱۹۸۶ y and from February to December of ۱۹۸۸. The first sharp change of ۴۴) corresponds to Parvany earthquake (۱۳,۰۵.۱۹۸۶), the second one to Spitak earthquake (۰۷.۱۲,۱۹۸۸),The tendency of returning movement of parameter N(A) to the initial value is observed after Spitak earthquake. It is supposed that the reason of parameter N(A) changes is the variation of electric conductivity of the rocks of terrestrial crust, which is created by the vertical filtration of high conducting fluids