Exploration of sub-instability before large earthquakes with the LURR method

Using the Load/Unload Response Ratio (LURR) method to identify sub-instability before large earthquakes seems to be a critical advancement in earthquake prediction and understanding the processes leading up to seismic events. By analyzing various earthquake-related observation data and discriminating between load and unload phases at observation stations, researchers were able to detect anomalies in stress states that indicate the potential for large earthquakes. The findings from retrospective studies on past earthquakes, such as the ones in Jiashi, Xinjiang, Menyuan, Qinghai, and Luding, Sichuan, provide significant evidence that LURR anomalies exceeding 2 standard deviations of the mean were observed at observation stations near the epicenter before the mainshocks. The decreasing distance between stations detecting LURR anomalies and the epicenter as the mainshock approached suggests a correlation between these anomalies and the impending earthquake. Overall, the identification of sub-instability through the LURR method and the spatio-temporal evolution of these anomalies could provide valuable insights into the weakening processes in the source media leading up to large earthquakes. This research has the potential to contribute to improved earthquake forecasting, ultimately enhancing our ability to mitigate the impacts of seismic events.