Balancing of geodetic and seismic moment rates and its implications for probabilistic seismic hazard analysis in Taiwan
Journal
Earth, Planets and Space
Journal Volume
77
Journal Issue
1
ISSN
1880-5981
Date Issued
2025-07-29
Author(s)
Abstract
An integration of geodetic data with observed seismicity which reveals how quickly a region is being deformed due to tectonic plate motions and earthquake activities, plays a pivotal role in earthquake forecast modeling. However, the elastic and inelastic components in geodetically measured total strain budget are implicit in nature, has become one of the major issues. In such scenarios, when reliable quantification of total accumulated energy related to seismic hazard appears to be the need of the hour, an empirical correlation factor is introduced in conversion of geodetic to seismic moment rates to prevent an overestimation of earthquake hazard. In this regard, the present study developed regional earthquake likelihood model for Taiwan by incorporating geodetic measurements and updated earthquake data. For this, a time-independent model is performed to compute probabilities for Mw≥6 earthquakes within 30 years in 0.1° × 0.1° cells across Taiwan using corrected-geodetic moment rates, truncated G–R law, and the stochastic Poisson process. The 30-year probability forecasts highlight regions with high seismic hazard, including the locked zone of the Longitudinal Valley fault with gradual decaying toward its southern end and in central Taiwan along the Western Foothills. The high strain rates and low earthquake occurrence rates in southwestern Taiwan emphasize a considerable amount of ongoing inelastic strain deformation in this region. In addition, the regional variation in probability distribution not only exhibits an importance of elastic layer parameters, such as seismogenic thickness and rigidity but also evidently link the heterogeneous tectonics with the orogenic process in Taiwan under the plate convergence. Essentially, this study suggests that an integration of geodetic data in probability model can offer rigorous insights for enhancing the current practice of forecasting strategies for seismic hazard analysis in Taiwan.
Subjects
Geodetic and seismic moment rates
Regional earthquake forecast model
Seismic hazard analysis
Taiwan
SDGs
Publisher
Springer Science and Business Media LLC
Type
journal article