Seismic Activity Patterns in Subduction Zones of the Philippine Sea Plate.

The Philippine Sea Plate plays a critical role in understanding lithospheric strength and seismic hazards due to its complex tectonic interactions and significant seismic activity. Studying this region provides valuable insights into the variations in effective elastic thickness (Te) and their implications for the geodynamics of subduction zones.
Data for this research was obtained from several key sources, including tectonic boundaries data, heat flow measurements, seismic activity records, and effective elastic thickness (Te) values. The Fan wavelet Bouguer coherence spectral technique was employed to analyze the Te variations across the study area. Heat flow data was sourced from the "Compilation of Heat Flow Data in Southeast Asia and Its Marginal Seas," seismic activity records were gathered from the USGS report "Seismicity of the Earth 1900-2012 Philippine Sea Plate and Vicinity," and Te data was derived from the study "Lateral variations of effective elastic thickness of the subducting Philippine Sea plate along the Nankai trough."
These findings highlight the significant variations in Te across the Philippine Sea Plate, with higher values in the northern and southern regions indicating a strong lithosphere, while lower values in the central region suggest a weaker lithosphere. The correlation between lower Te values and increased seismic activity underscores the importance of lithospheric strength in assessing seismic hazards. By incorporating Te and geothermal data into probabilistic models, this research enhances the accuracy of earthquake risk assessments and provides valuable insights into the dynamics of subduction zones. Future research should focus on high-resolution seismic and geothermal measurements to further refine our understanding of lithospheric dynamics in this region.