Paleomagnetic studies of igneous rocks of the Avachinsky volcano are carried out and preliminary results of determining the angular elements of the geomagnetic field are obtained. The direction of the geomagnetic field was determined for the most stable part of the natural remanent magnetization of 53 samples from 7 sites: 18 samples from 3 sites (sampling point N 53° 12’, E 158° 48’) from the lava flow of the historical eruption of 1827 and 35 samples from 4 sites (sampling point N 53° 16’, E 158° 49’) from the lava flow which age exceeds 3500 years. Using the first group of samples (N = 3), the position of the virtual geomagnetic pole was obtained with the coordinates Plat = 66º ± 4º, Plong = 266º ± 5º, which, within the error, coincides with the position of the north magnetic pole, registered in 1831. For the second group of samples (N = 4), the coordinates of the virtual geomagnetic pole are Plat = 83º ± 3º, Plong = 254º ± 21º. Based on a comparison of the obtained coordinates of the virtual geomagnetic pole and paleointensity with the paleosecular variations of the magnitude and direction of the Earth’s dipole magnetic moment over the past 9000 years, it is concluded that the second investigated flow refers to the lava eruption that occurred about 5000-5500 years ago.
91.25.Le Time variations in geomagnetism
$^1$MSU, Faculty of Physics, department of physics of the Earth
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