Ionospheric precursors of strong earthquakes observed using six GNSS stations data during continuous five years(2011-2015)

作     者：H.E.Eshkuvatov B.J.Ahmedov Y.A.Tillayev M.Arslan Tariq M.Ali Shah Libo Liu H.E.Eshkuvatov;B.J.Ahmedov;Y.A.Tillayev;M.Arslan Tariq;M.Ali Shah;Libo Liu

作者机构：Ulugh Beg Astronomical InstituteAstronomy St.33Tashkent 100052Uzbekistan National University of UzbekistanUniversity St.4Tashkent 100174Uzbekistan Institute of Fundamental and Applied ResearchNational Research University TIIAMEKori Niyoziy 39Tashkent 100000Uzbekistan Centre for Earthquake StudiesNational Centre for PhysicsIslamabadPakistan Key Laboratory of Earth and Planetary PhysicsInstitute of Geology and GeophysicsChinese Academy of SciencesBeijingChina College of Earth and Planetary SciencesUniversity of Chinese Academy of SciencesBeijing 100049China Heilongjiang Mohe Observatory of GeophysicsInstitute of Geology and GeophysicsChinese Academy of SciencesBeijingChina 

出 版 物：《Geodesy and Geodynamics》 (大地测量与地球动力学（英文版）)

年 卷 期：2023年第14卷第1期

页      面：65-79页

核心收录：

学科分类：070801[理学-固体地球物理学] 07[理学] 0708[理学-地球物理学] 

基　　金：supported by the National Natural Science Foundation of China (42030202)。 

主　　题：GNSS TEC Earthquakes Ionospheric precursors 

摘      要：This study reports the morphological characteristics of anomalous variations in Global Navigation Satellite System Total Electron Content(GNSS-TEC) prior to the strong local earthquakes(EQ) that occurred during the period of 2011-2015.We have analyzed 20 earthquakes of magnitude M 5.6.A statistical technique is implemented on the data of six GNSS stations located in Tashkent,Kitab,and Maidanak in Uzbekistan,and Islamabad,Multan,Quetta in Pakistan.The results show continuous anomalous variations in TEC during 24 h befo re the occupancy of local earthquakes.It is shown that the precursors before the occurrence of strong earthquakes,in particular of magnitude 5.7,7.7,7.5,7.8 and 7.3 are detected near Eastern Uzbekistan(26 May 2013),Southwestern Pakistan(24 September 2013),Hindukush region of Afghanistan(26 October 2015),and Central Nepal(25 April 2015) and(12 May 2015),respectively.The ionospheric anomalies appearing before the strong earthquakes at six GNSS stations are registered in 14cases(70%) out of 20 selected EQs.It is depicted that anomalies referred to as ionospheric precursors appeared about 1-7 days prior to the occurrence of strong earthquakes.