{"title":"用磁力计反问题求解地核磁场源的详细模型","authors":"V. Kochnev","doi":"10.2113/rgg20224493","DOIUrl":null,"url":null,"abstract":"\n —Magnetic field sources are sometimes approximated by magnetic dipoles or current loops. The usefulness of such approximations is not obvious at the initial stage of the study of objects. Investigating them in detail requires volumetric magnetic field sources. In this paper, they are represented by magnetized prisms. Such a model is valid due to the equivalence of current and magnetized objects. As there should be no real magnetization in the core, this property of a virtual prism to generate a magnetic field strength is referred to as virtual or effective magnetization (EM), which is determined for each prism by solving the inverse problem via the adaptive method. Initial data for solving the inverse problem are the Z vector components of the main magnetic field of the IGRF-2005 model in the geocentric coordinate system. Based on the effective magnetization and known formulas, the bulk current distribution, the bulk current density, and the magnetic moments of prisms of a two-layer core model are obtained. Their sum coincides with the magnetic moment of the virtual central dipole of the core, but, as many scientists assumed, the central dipole is not actually distinguished. At the same time, four significant inhomogeneities are identified in the core, which create the Canadian, Siberian-Asian, Australian, and negative South Atlantic global anomalies on the Earth’s surface. Based on the analysis of the results obtained, assumptions are made that the current generating the magnetic field is the motion of a positively weakly charged liquid of the core. Liquid motion is created by the rotation of the Earth and the decelerating gravitational forces of the Moon and the Sun. Arguments are given to support these assumptions. The results are illustrated in figures.","PeriodicalId":49587,"journal":{"name":"Russian Geology and Geophysics","volume":" ","pages":""},"PeriodicalIF":1.2000,"publicationDate":"2023-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"A Detailed Model of Magnetic Field Sources of the Earth’s Core Obtained by Solving the Inverse Problem of Magnetometry\",\"authors\":\"V. Kochnev\",\"doi\":\"10.2113/rgg20224493\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"\\n —Magnetic field sources are sometimes approximated by magnetic dipoles or current loops. The usefulness of such approximations is not obvious at the initial stage of the study of objects. Investigating them in detail requires volumetric magnetic field sources. In this paper, they are represented by magnetized prisms. Such a model is valid due to the equivalence of current and magnetized objects. As there should be no real magnetization in the core, this property of a virtual prism to generate a magnetic field strength is referred to as virtual or effective magnetization (EM), which is determined for each prism by solving the inverse problem via the adaptive method. Initial data for solving the inverse problem are the Z vector components of the main magnetic field of the IGRF-2005 model in the geocentric coordinate system. Based on the effective magnetization and known formulas, the bulk current distribution, the bulk current density, and the magnetic moments of prisms of a two-layer core model are obtained. Their sum coincides with the magnetic moment of the virtual central dipole of the core, but, as many scientists assumed, the central dipole is not actually distinguished. At the same time, four significant inhomogeneities are identified in the core, which create the Canadian, Siberian-Asian, Australian, and negative South Atlantic global anomalies on the Earth’s surface. Based on the analysis of the results obtained, assumptions are made that the current generating the magnetic field is the motion of a positively weakly charged liquid of the core. Liquid motion is created by the rotation of the Earth and the decelerating gravitational forces of the Moon and the Sun. Arguments are given to support these assumptions. The results are illustrated in figures.\",\"PeriodicalId\":49587,\"journal\":{\"name\":\"Russian Geology and Geophysics\",\"volume\":\" \",\"pages\":\"\"},\"PeriodicalIF\":1.2000,\"publicationDate\":\"2023-02-25\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Russian Geology and Geophysics\",\"FirstCategoryId\":\"89\",\"ListUrlMain\":\"https://doi.org/10.2113/rgg20224493\",\"RegionNum\":4,\"RegionCategory\":\"地球科学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"GEOSCIENCES, MULTIDISCIPLINARY\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Russian Geology and Geophysics","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.2113/rgg20224493","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"GEOSCIENCES, MULTIDISCIPLINARY","Score":null,"Total":0}
A Detailed Model of Magnetic Field Sources of the Earth’s Core Obtained by Solving the Inverse Problem of Magnetometry
—Magnetic field sources are sometimes approximated by magnetic dipoles or current loops. The usefulness of such approximations is not obvious at the initial stage of the study of objects. Investigating them in detail requires volumetric magnetic field sources. In this paper, they are represented by magnetized prisms. Such a model is valid due to the equivalence of current and magnetized objects. As there should be no real magnetization in the core, this property of a virtual prism to generate a magnetic field strength is referred to as virtual or effective magnetization (EM), which is determined for each prism by solving the inverse problem via the adaptive method. Initial data for solving the inverse problem are the Z vector components of the main magnetic field of the IGRF-2005 model in the geocentric coordinate system. Based on the effective magnetization and known formulas, the bulk current distribution, the bulk current density, and the magnetic moments of prisms of a two-layer core model are obtained. Their sum coincides with the magnetic moment of the virtual central dipole of the core, but, as many scientists assumed, the central dipole is not actually distinguished. At the same time, four significant inhomogeneities are identified in the core, which create the Canadian, Siberian-Asian, Australian, and negative South Atlantic global anomalies on the Earth’s surface. Based on the analysis of the results obtained, assumptions are made that the current generating the magnetic field is the motion of a positively weakly charged liquid of the core. Liquid motion is created by the rotation of the Earth and the decelerating gravitational forces of the Moon and the Sun. Arguments are given to support these assumptions. The results are illustrated in figures.
期刊介绍:
The journal publishes original reports of theoretical and methodological nature in the fields of geology, geophysics, and geochemistry, which contain data on composition and structure of the Earth''s crust and mantle, describes processes of formation and general regularities of commercial mineral occurrences, investigations on development and application of geological-geophysical methods for their revealing. As to works of regional nature, accelerated publication are available for original papers on a variety of problems of comparative geology taking into account specific character of Siberia, adjacent Asian countries and water areas. The journal will also publish reviews, critical articles, chronicle of the most important scientific events, and advertisements.