Аннотация:Abstract—Before the 15 strongest earthquakes in California with magnitudes M6.5+ from 1984 to 2023, ananalysis of seismicity anomalies was conducted using two parameters: the b-value and the RTL function. Spatiotemporalanomalous areas were identified based on known precursors for these parameters. The values oftuning coefficients for the calculation algorithms and catalog filtering parameters selected for the analysis ofeach earthquake are presented. Characteristics of the anomalies were determined, including their duration,size, and distance from the center of the anomaly to the earthquake epicenter. A comparison of anomaly durationsrevealed that, for most earthquakes, RTL parameter anomalies occur earlier than b-value anomalies.This sequence of anomaly occurrence differs from the sequence found by the authors previously when analyzingstrong earthquakes in subduction zones and rift zones. A significant portion of the earthquakes studiedin California occur with a delay of several months after the completion of the bay-like anomalies of the RTLparameter, which reflect the end of the formation of a metastable region in the medium. Meanwhile, abnormallylow values of b-value persist until the moment of the earthquake.
