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Modelling of space weather effects on pipelines 总被引：1，自引：0，他引：1
Antti Pulkkinen Risto Pirjola David Boteler Ari Viljanen Igor Yegorov 《Journal of Applied Geophysics》2001,48(4)
The interaction between the solar wind and the Earth's magnetic field produces time varying currents in the ionosphere and magnetosphere. The currents cause variations of the geomagnetic field at the surface of the earth and induce an electric field which drives currents in oil and gas pipelines and other long conductors. Geomagnetically induced currents (GIC) interfere with electrical surveys of pipelines and possibly contribute to pipeline corrosion.In this paper, we introduce a general method which can be used to determine voltage and current profiles for buried pipelines, when the external geoelectric field and the geometry and electromagnetic properties of the pipeline are known. The method is based on the analogy between pipelines and transmission lines, which makes it possible to use the distributed source transmission line (DSTL) theory. The general equations derived for the current and voltage profiles are applied in special cases. A particular attention is paid to the Finnish natural gas pipeline network.This paper, related to a project about GIC in the Finnish pipeline, thus provides a tool for understanding space weather effects on pipelines. Combined with methods of calculating the geoelectric field during magnetic storms, the results are applicable to forecasting of geomagnetically induced currents and voltages on pipelines in the future. 相似文献
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The origin of background fluctuations in the natural electric field observed in the measurements on the seafloor of shallow seas and oceans, as well as in the lakes and estuaries of large rivers is considered. It is shown that the presence of these fluctuations, which have a quasi-harmonic behavior, is due to the surface waves and can be accounted for by the action of the (1) magnetohydrodynamic and/or (2) electrokinetic effects, with the predominance of the latter in the freshwater basins. The excitation models of the background fluctuations in the electric field by both the long surface waves and interacting short waves are analyzed. The estimates of the electric field of background fluctuations are obtained. 相似文献
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I. V. Yegorov 《Izvestiya Physics of the Solid Earth》2009,45(9):812-821
The algorithm for numerically solving the direct 3-D problem of calculating the electromagnetic field varying harmonically
in an arbitrary inhomogeneous 3-D media is developed on the base of the Trefftz method, which has not been used previously
in geoelectrics. The corresponding system of algebraic equations has been solved with the use of a modification of the well-known
Kaczmarz iterative method. A cyclic method of equalization is used as a procedure of preconditioning the matrix of the system. 相似文献
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Alexeev N. L. Maslov V. A. Kaminsky V. D. Semenov V. S. Bogomolov E. S. Kapitonov I. N. Gonzhurov N. A. Melnik A. Yu. Yegorov M. S. 《Doklady Earth Sciences》2019,487(2):902-907
Doklady Earth Sciences - This work presents results of isotope studies of primary igneous and sedimentary rocks of Mawson and Menzies series from the southern Prince Charles Mountains, East... 相似文献
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I. V. Yegorov 《Izvestiya Physics of the Solid Earth》2011,47(2):90-100
The Trefftz method is applied to the numerical solution of the three-dimensional (3D) forward problem for an electromagnetic field harmonically oscillating with time in a 3D environment, which ensures the possibility to solve a 3D inverse problem. Here, the known idea of simultaneous joint interpretation of the tangential components of electric and magnetic fields measured on the Earth's surface, which was suggested by A.N. Tikhonov for the development of the electromagnetic sounding method, is employed in the context of the numerical-analytical representation of the forward problem solution in accordance with the Trefftz method. Application of this method allows enables one to generalize the basic plane-stratified vertically 1D model of the medium by allowing for lateral variations in electric conductivity. 相似文献
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A. I. Tikhonov M. S. Golitsyn V. P. Tikhonov A. F. Ivanov S. P. Yegorov R. I. Gafurov N. E. Mironova A. V. Vasil’ev 《Water Resources》2007,34(2):229-234
The possibility and expediency of the use of groundwater from the Upper Permian aquifers of the right-bank area of the Volga River as an alternative to the Cheboksary aquifer are shown on the basis of multipurpose studies using uranium-isotope and microelement hydrogeochemical methods. Currently, the Cheboksary aquifer is under exploration in Quaternary deposits of the left-bank area and is meant for centralized environmentally most safe supply of drinking water to the population of the towns of Cheboksary and Novocheboksarsk. 相似文献
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A. Ádám L.L. Vanyan D.A. Varlamov I.V. Yegorov A.P. Shilovski P.P. Shilovski 《Physics of the Earth and Planetary Interiors》1982,28(3):251-260
On the basis of numerical modelling and statistical investigations of the horizontal electrical inhomogeneities (narrow fractures, change of conductance of the surface sediments) ρmin magnetotelluric (MT)-sounding curves were found to be less distorted and, therefore, they can be used for the determination of deep conducting formations in the crust and upper mantle.Carefully selected MT curves indicate the crustal conductive layer at depths of 7–13 km and the conductive asthenosphere between 50 and 80 km.The relatively shallow position of the asthenosphere corresponds to the high heat flow (q > 80 mWm?1) in the Pannonian basin according to the empirical relation derived by Ádám (1978). 相似文献
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L.V. Yegorov E.L. Chernyak N.A. Palshin T.A. Demidova P. Kaikkonen 《Physics of the Earth and Planetary Interiors》1983,33(1):56-63
The distortions of the electromagnetic-plane wave field, due to near-surface conductivity inhomogeneities, are considered. The real three-dimensional distribution of the shallow conductivity is approximated by Price's thin-sheet model. As low-frequency magnetotelluric variations are considered it is possible to neglect the self-induction in the thin sheet.The calculation of the current function has been carried out by the alternative Schwarz method. The method combines, in the iterative sense, the finite element solution in the inhomogeneous region and the analytical solution outside of it. The primary electric field is assumed to be circularly polarized. An example for the Baltic Shield shows that the telluric field is mostly very distorted. 相似文献
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