Spatiotemporal Characteristics of Horizontal Crustal Deformation in the Sichuan–Yunnan Region Using GPS Data

Based on various velocity fields from Global Positioning System (GPS) data over nearly 20 years in the Sichuan–Yunnan region, this paper calculated strain rate field and its spatiotemporal characteristics by using an improved least squares collocation method. We evaluated extensively discussing impact of non-tectonic factors calculation. Subsequently, we described present-day features their variations. The results indicate necessity considering influence when calculating GPS data. Widespread accumulation is observed significant second invariant with average value 33.1 nanostrain/yr primarily occurs along eastern boundary faults rhomboid block, specifically Xianshuihe–Anninghe–Zemuhe–Xiaojiang fault systems. These systems also demarcate zones negative positive dilation strain. According to variations fields, northern southern segments Xianshuihe Fault, Anninghe Fault adjacent faults, Xiaojiang are undergoing intensifying Consequently, these should be paid more attention due relatively higher seismic risk region.