The Anomalous Behaviour of Geomagnetic Variations of Short Period in Japan and Its Relation to the Subterranean Structure. The 6th report. : The results of further observations and some considerations concerning the influences of the sea on geomagnetic va

New results of the recent observations are described in regard to the anomalous distribution of short-period geomagnetic variations in Japan. The possible influence of the sea on the variations is also studied from the standpoint of the electromagnetic induction theory. It is made clear that the observed results can not be explained by the effect of the electric currents induced in the sea. An interpretation concerning a possible cause of the phenomenon is also attempted.日本における地磁気短周期変化の異常に関連して,伊豆大島に臨時観測所を設けて約2ケ月連続観測を行つた.大島においてもΔZのΔHに対する著しい相似性と,大きな比を認めた.即ち大島も油壷,柿岡を含む異常地域に属するものである.油壷,間瀬においてその後えられた観測結果を加えて,新たに統計的に調べると,その地磁気変化にそれぞれ異方性が認められる.両者とも,理論的に求められた正常分布からそれぞれの様相を以て偏倚している