Toshihiko IyemoriMasahito NoseDesheng HanYufen GaoMichio HashizumeNithiwatthn ChoosakulHiroyuki ShinagawaYoshikazu TanakaMitsuru UtsugiAkinori SaitoHeather McCreadieYoko OdagiFuxi YangKyoto UniversityPolar Research Institute of ChinaChina Earthquake AdministrationMahidol UniversityJapan National Institute of Information and Communications TechnologySeismological Bureau Xinjiang Uygur Autonomous Region2018-06-212018-06-212005-10-28Geophysical Research Letters. Vol.32, No.20 (2005), 1-4009482762-s2.0-28944447374https://repository.li.mahidol.ac.th/handle/20.500.14594/16488A long period Pc5 pulsation was observed at Phimai in Thailand, shortly after the origin time of the Sumatra earthquake on December 26, 2004. The localized nature and the period of oscillations suggest that the long period magnetic pulsation was generated by dynamo action in the lower ionosphere, set up by an atmospheric pressure pulse which propagated vertically as an acoustic wave when the ocean floor suddenly moved vertically. It is speculated that a Pc3 type pulsation observed at Tong Hai in China, 10 degrees north of Phimai in latitude, was the result of magnetic field line resonance with a magnetosonic wave generated from the electric and magnetic fields of the dynamo current caused by the Earthquake. Copyright 2005 by the American Geophysical Union.Mahidol UniversityEarth and Planetary SciencesArticleSCOPUS10.1029/2005GL024083