A Comprehensive Crustal Coda Attenuation Map of Continental China

Abstract

Seismic coda wave attenuation (Q_C) reflects both intrinsic inelasticity and small-scale heterogeneities in the Earth's crust, offering insights into its thermal state and structural complexity. Continental China, characterized by widespread plate boundary deformation, is among the most tectonically active regions globally. Using over a decade of data from the China National Seismic Network, we apply the Multiple Station and Multiple Event Method to estimate station-side Q_C across 1–14 Hz, yielding high-resolution maps that reveal block-scale patterns aligned with tectonic boundaries. The Northeast, South, and North China blocks show consistently high Q_C values, while significantly lower values are observed in Xinjiang, Tibetan Plateau, and North–South Seismic Belt, consistent with theoretical expectations that low values are observed in active regions. Furthermore, we identify a negative correlation between Q_C and shear strain rate at higher frequencies, suggesting a fundamental link between attenuation and crustal stress heterogeneity.