Satellite Detects Pre-Earthquake Thermal Anomalies Associated with Past Major Earthquakes
Arun K Saraf
Department of Earth Sciences
Indian Insitute of Technology Roorkee, India
Email: [email protected]
Analyzing past earthquakes and their characteristics, perhaps a better understanding about the earthquake phenomena can be made. Pressure built-up due to tectonic activities and also associated subsurface degassing might create changes in thermal regime and if by any technique this change is detected, it can provide very important clues about future earthquake activities. Thermal satellite remote sensing which can sense the earth’s surface emissivity at regular interval introduces a new way of analyzing this phenomenon. Using NOAA-AVHRR thermal infrared time series datasets, three major past earthquakes in Bhuj (India), Boumerdes (Algeria) and Bam (Iran) were analyzed for studying the thermal changes before and after the earthquakes. The study was successful in detecting pre-earthquake thermal anomalies prior to all these earthquakes. Significant thermal anomalies with a rise in temperature of about 7-10°C in the vicinity of the epicenters have been observed. The anomalies disappeared along with the events. Further, using passive microwave SSM/I sensor datasets from DMSP satellites the occurrence of the phenomenon of pre-earthquake thermal anomalies for eight earthquakes in India, China, Turkey, Afghanistan and Pakistan were observed.