Satellite thermal IR and atmospheric radon anomalies associated with the Haripur earthquake (Oct 2010; Mw 5.2), Pakistan

The recent scientific progress in the context of earthquake forecasting reveals some key physical processes related to seismic activity. The lithosphere-atmosphere-ionosphere coupling model provides a comprehensive mechanism to understand the underlying key physical processes. In this study, a precursory analysis was conducted for the shallow, moderate-magnitude Haripur earthquake (Oct 2010; Mw 5.2) bounded by two major water reservoirs, highlighting its significance. This precursory analysis was performed using the land surface temperature (LST) extracted from satellite (MODIS) thermal infrared data and atmospheric radon concentration recorded at Islamabad and Murree stations using radon monitors. A significant change in LST (4-8 °C) was observed in the epicentral region 6 days prior to this event. In addition, a comparison was made between daily and five-year-averaged LST that further supports our results. The radon concentration also showed anomalous behavior 3-4 days prior to this particular event with crucial meteorological indicators in the safe limit. This abnormal behavior of both precursors prior to this event proposes a possible correlation with the local seismic activity. Moreover, the higher amplitude of radon anomaly at the nearest station (Islamabad) is also validating its local cause. The results presented in this study are very encouraging and stimulate the idea of earthquake forecasting using multi-precursory approach.