Thermal anomaly detection for 2013 Lushan earthquake

Abstract

For some strong earthquakes, thermal anomaly occurs before the event, however not definitely. In this study, time series of MODIS Land Surface Temperature (LST) products have been processed and analyzed to locate possible anomalous variations prior to the Lushan (20 April 2013) earthquakes. In order to exclude the seasonal or annual effects from the LST variations, also to avoid the rainy and cloudy weather in this area, the 10-day mean LST data are derived using daily MODIS LST products from 2001 to 2012. The 10-day mean LST data from January to May of 2013 were differenced using the above background. RX anomaly detection algorithm was then used to detect the anomalies. It is found that most anomalies are around the Longmenshan fault zone, indicating that LST change detection is effective in this area for precursor study.