Secular variations of the geomagnetic field on litosphere plates of the Earth

P. V. Sumaruk, T. P. Sumaruk


The dependence of the value and sign of the geomagnetic secular variations (SV) refined of 3- and 11-year components on the position of observatories at different tectonic plates is investigated. The observatories of the long row observations were used for the studies. It is shown, that SV contain the components from internal and external sources. The values of the components change from plate to plate and even on the same plate. The secular variations have greater amplitudes in the regions with the intensive tectonic processes. Ten regions, having peculiar character of the SV, are distinguished. Secular variation may be of opposite phases in different tectonic plates, but extremes of their curves of hourly changes and the change of SV sign in most cases coincide with maximums and minimums of solar and geomagnetic activities. The assumption is made that internal and external sources of SV of the geomagnetic field are mutually connected. External sources play an important role in generation of SV. The maximal amplitudes of SV during all observational period were observed in two regions: the first region — the eastern part of the North-American plate, Caribbean plate and the northern part of the South-American plate, the second region — the western part of the Indian ocean. The value of SV component from the external sources depends on the geomagnetic latitudes of the observation places. Its amplitude increases with the increase of latitude of the observatories. The maximal values of SV components from external sources are observed at the magnetic and geomagnetic poles. The influence of the external sources on SV value is observed at the observatories placed under equatorial ionospheric electrojet. The main peculiarity of the nowadays geomagnetic field secular variations is decreasing the field intensity in the most regions of the Earth. In the second half of the twentieth century the regular small increasing of the field is observed only in the European part of Eurasian plate.


geomagnetic field; secular variation; external sources; lithospheric plates


Bondar T. N., Golovkov V. P., Yakovleva S. V., 2006. The geomagnetic field in the XX century. Geomagnetizm i aeronomiya 46(3), 409—412 (in Russian).

Vitinskiy Yu. I., 1973. Cyclicity and solar activity prediction. Moscow: Nauka, 183 p. (in Russian).

Demina I. M., Koroleva T. Yu., Farafonova Yu. G., 2008à. Anomalies in the secular variations in the main geomagnetic field in the context of the hierarchic dipole model. Geomagnetizm i aeronomiya 48(6), 849—858 (in Russian).

Demina I. M., Nikitina L. V., Farafonova Yu. G., 2008b. Secular variation in the main geomagnetic field within the scope of the dynamic model of field sources. Geomagnetizm i aeronomiya 48(4), 567—575 (in Russian).

Demina I. M., Farafonova Yu. G., 2004. Dipole model of the main geomagnetic field in the XX century. Geomagnetizm i aeronomiya 44(4), 565—570 (in Russian).

Zharkov V. N., 1963. The internal building of the Earth. Moscow: Nauka, 416 p. (in Russian).

Kalinin Yu. D., 1984. Secular geomagnetic variation. Novosibirsk: Nauka, 160 p. (in Russian).

Kasyanenko L. G., Demina I. M., Sos-Ukhrinovskiy A., 2002. Presentation of the main field of the Earth by the system of optimal on orientation and positions dypoles. Geomagnetizm i aeronomiya 42(6), 838—844 (in Russian).

Orlov V. P., Ivchenko M. I., Bazarzhapov A. D., Kolomiytseva G. I., 1968. Secular changes of the geo-magnetic field for 1960—1965. Moscow: IZMIRAN, 68 p. (in Russian).

Orlyuk M., Marchenko A., Romenets A., 2016. Earth’s seismicity and secular changes of its magnetic field. Visnyk Kyyivskoho natsionalnoho universytetu. Heolohiya (4), 50—54 (in Ukrainian).

Ruzmaykin A. A., Sokolov D. D., Shukurov A. M., 1989. On the nature of the main geomagnetic field secular variations. Geomagnetizm i aeronomiya 29(6), 1001—1006 (in Russian).

Sumaruk T. P., Sumaruk P. V., 2009. Quasi two year variations of the Earth’s magnetic field. Dopovidi NAN Ukrayiny (1), 114—116 (in Ukrainian).

Sumaruk Yu. P., Sumaruk T. P., 2013. About the contribution of external sources in the age variation of the geomagnetic field. Dopovidi NAN Ukrayiny (12), 107—113 (in Ukrainian).

Tyapkin K. F., 1974. The new rotation hypothesis of the tectonic structures formation in the Earth’s crust. Geologicheskiy zhurnal (4), 3—16 (in Russian).

Tyapkin K. F., 1996. The new rotation model of the Earth’s magnetic field. Geologicheskiy zhurnal (4), 3—16 (in Russian).

Shevnin A. D., Levitin A. E., Gromova L. I., Dremukhina L. A., Kaynara L. N., 2009. Solar cyclic variation in magnetic elements of Moscow observatory. Geomagnetizm i aeronomiya 49(3), 315—320 (in Russian).

Data catalogue. WDC, Kyoto, 2005. 183 p.

Finlay C. C., Olsen N., Kotriaros S., Gillet N., Toffner-Clausen L., 2016. Recent geomagnetic secular variation from Swarm and ground observatories as estimated in the CHAOS-6 geomagnetic field model. Earth Planets Space 68(112). doi: 10. 1186/s40623-016-0486-1.

Golovkov V. P., Bondar T. N., Burdelnaya I. A., Yakovleva S. U., 1997. Using satellite magnetic survey for Spatial — temporal modeling of the geomagnetic secular variation. J. Geomag. Geoelectr. 49, 207—227.

Langel R. A., Estes R. H., 1985. The near-earth mag-netic field at 1980 determined from MAGSAT data. J. Geophys. Res. 90, 2495—2509.

Olsen N., 2002. A model of the geomagnetic field and its secular variations for epoch 2000 estimated from Orsted data. Geophys. J. Int. 149, 454—462.

Sumaruk Yu., 2000. Sources of secular variations of the Earth’s magnetic field. Contrib. Geophys. Geod. 30(2), P. 158.

Verbanac G., Luhr H., Rother M., Korte M., Mandea M., 2007. Contributions of the external field to the observatory annual means and a proposal for their corrections. Earth Planets Space 59, 251—257.



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