Anomalous variation in GPS TEC prior to the 11 April 2012 Sumatra earthquake

作者：Zhu, Fuying^*; Zhou, Yiyan; Wu, Yun

来源：Astrophysics and Space Science, 2013, 345(2): 231-237.

DOI：10.1007/s10509-013-1389-2

• Anomalous variation
• GPS TEC
• Precursors of earthquakes

On 11 April 2012, a strong earthquake of magnitude Ms8.6 occurred near the west coast of Northern Sumatra, Indonesia. In this paper, we investigated the morphological characteristics of anomalous variations in Global Positioning System Total Electron Content (GPS TEC) prior to the earthquake by the method of the statistical analysis. It was found the TEC anomaly was firstly decreased, then, it became more enhanced, finally, it decreased, the peak of anomaly enhancement arose from 13:00-17:00 LT on April 5 lasted for similar to 4 hours and the anomalous ionospheric regions extended to similar to 40 degrees in longitude and similar to 20 degrees in latitude, its location did not coincide with the vertical projection of the epicenter, but lies at the north and south of the geomagnetic equator, meanwhile, corresponding ionospheric anomalies are also observed in the magneto conjugate region. Potential causes of these results are discussed,eliminating the ionospheric anomalies that may be caused by solar activities and magnetic storms, it can be concluded that the observed obvious anomalous variation in GPS TEC on April 5 were possibly related to the earthquake.

• 出版日期2013-6
• 单位中国地震局; 中国地震局地震研究所