Electromagnetic induction in non-uniform conductors, and the determination of the conductivity of the earth from terrestrial magnetic variations
Electromagnetic induction in non-uniform conductors, and the determination of the conductivity of the earth from terrestrial magnetic variations
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DOI：
10.1098/rsta.1939.0001
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发表时间：
1939-01-01
影响因子：
--
通讯作者：
Price, AT
中科院分区：
文献类型：
--
作者：
Lahiri, BN;Price, AT
从观测到的地球磁场变化中获得地球内部电导率分布的一些知识的可能性，首先由舒斯特（1889）在发展他的每日磁场变化理论时考虑。他将这些变化分为外部和内部起源的部分，然后应用兰姆（1883）的均匀球体中的电磁感应理论，以表明“内部”部分可以归因于“外部”部分在地球中感应的电流。Chapman（1919）对日变化场作了更全面的分析，并表明这与地球具有一个电导率k = 3.6 × 10 -13 e.m.u.的地核是一致的，被一个大约250公里的不导电外壳包围着。厚然而，Chapman和Whitehead（1922）发现，相对高导电的海洋可能对内部场有明显的影响，因此在k的估计中引入了一些不确定性。
The possibility of obtaining some knowledge of the distribution of electrical conductivity within the earth, from the observed variations of the earth’s magnetic field, was first considered by Schuster (1889), in developing his theory of the daily magnetic variations. He separated these variations into parts of external and internal origin, and then applied the theory of electromagnetic induction in a uniform sphere, due to Lamb (1883), to show that the “internal” part could be attributed to electric currents induced in the earth by the “external” part. Chapman (1919) made a more complete analysis of the diurnal variation field, and showed that it was consistent with the earth having a core of conductivity k = 3.6 x l 0-13 e.m.u., surrounded by a non-conducting shell of about 250 km. thickness. Chapman and Whitehead (1922) found, however, that the relatively highly conducting oceans probably have an appreciable effect on the internal field, and thus introduce some uncertainty in the estimate ofk.