Anomalous Signal Analysis of Satellite Based Thermal Infrared and Ground Based Radon Data Recorded Prior to Major Earthquakes in Pakistan

English Abstract:

This study is based on the record of Thermal Infrared (TIR) satellite data regarding anomalous behavior of energy emitted from Earth’s surface prior to occurrence of four major earthquakes in Pakistan, Kashmir Mw7.6 on October 08, 2005, Ziarat Mw6.4 on October 28, 2008, Dalbandin Mw7.2 on January 18, 2011 and Haripur Mw5.2 on October 11, 2010. The data from Moderate Resolution Imaging Spectro-radiometer (MODIS) onboard Aqua and TERRA satellites, pre- and post- earthquake cloud-free pertaining to thermal infrared region were analyzed. For each earthquake event, a five-year dataset prior to the event was also analyzed to find the average surface temperature field of the corresponding area as a background field. The maximum, minimum and average radiance and the corresponding temperature values were computed as references. Anomalies start to appear about a month to several days before the occurrence of major earthquake with covering area of thousands square km. Our analysis showed that the variation of surface temperature value was 1 to 8º C. The average temperature manifests decrease trend just 1–2 days before the earthquake and attains its normal behavior after the occurrence of earthquake. The maximum energy was shifted towards the epicenters during that period. The location of the epicenter was found within the anomaly area. Radon was monitored in the air above the earth at ground based network since 2010. For Haripur earthquake event, Radon data spanning from 1 to 16 October 2010 recorded at the nearest three radon stations installed at Nurpur, Shahdra and Murree, were also analyzed. The radon anomaly was observed on two stations with the increase from 2-3 Pci/l to 6-7Pci/l, 1-2 days prior to the occurrence of the event. The third station, Murree, did not record any anomaly during this period.