Analysis of GPS TEC anomalies associated with Mw > 7 earthquakes in Japan


  • Asim Khan Department of Space Science, Space Education and GNSS Lab, National Centre of GIS and Space Application, Institute of Space Technology, Islamabad, Pakistan.
  • Munawar Shah Department of Space Science, Space Education and GNSS Lab, National Centre of GIS and Space Application, Institute of Space Technology, Islamabad, Pakistan | College of Surveying and Geo Informatics, Tongji University, Shanghai, China.
  • Sajjad Ali GRI, BGP, China National Petroleum Corporation (CNPC), Abu Dhabi, United Arab Emirates.



GPS stations, Ionospheric anomalies, Earthquake precursor, Depth of Earthquake, Magnitude of Earthquake, Space parameters, Ground parameters, Seismic activity


The Global Positioning System (GPS) provides insights into the Earthquakes (EQs) ionospheric anomalies. Different space-and-ground parameters are used to observe EQ precursors. This paper uses the Total Electron Content (TEC) from nearby operating GPS stations to detect perturbation in the ionosphere before and after four EQs in Japan in 2011. In addition, the TEC variations in relation to the depth and magnitude of the EQs are noticed. The analysis shows significant variations in TEC to depth and magnitude in association with each main shock. TEC value abruption starts on 8 March and continues for 6 days in March. In April, TEC abnormalities start 5 days before and after the man shock. The geomagnetic Kp index is higher than four from March 10 to 12. The anomalies in this study are clearly associated with geomagnetic storms, as the Kp index is active. Moreover, the Dst index is below the negative 50 (nT) in the seismic period of March and April. The ionosphere parameters will define the severity of seismic activity in future.


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How to Cite

Khan, A., Shah, M., & Ali, S. (2023). Analysis of GPS TEC anomalies associated with Mw > 7 earthquakes in Japan. Asian Journal of Science, Engineering and Technology (AJSET), 2(1), 69–79.



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