Earthquake potential in the peripheral zones of the Ordos Block based on contemporary GPS strain rates and seismicity

• Published in: Tectonophysics Vol. 824; p. 229224
• Main Authors: Zhu, Shoubiao, Chen, Jie, Shi, Yaolin
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 05.02.2022; Elsevier BV
• Subjects: Deformation; Earthquake potential; Earthquake prediction; Earthquakes; Environmental risk; Geological hazards; Geology; GPS data; Graben; High strain rate; Ordos Block; Seismic activity; Seismic hazard; Seismicity; Strain rates; Vectors; GPS data; Seismic hazard; Earthquake potential; Ordos Block; Strain rates; Seismicity
• ISSN: 0040-1951; 1879-3266
• DOI: 10.1016/j.tecto.2022.229224

Historically, devastating major earthquakes have occurred frequently in the peripheral zones of the Ordos Block. Thus, identifying possible locations of future catastrophic earthquakes in these regions is urgent both in the scientific community and in the public. For this purpose, we at first compute strain rates by means of GPS vectors and b-value from seismicity, then obtain geodetic earthquake potential. The calculation results show that high strain rates are mainly distributed in the peripheral zones of the Ordos Block with very small deformation in the interior of the Block, in good agreement with geology and seismicity. Based on seismic potential, considering historical and modern seismicity, and neotectonic structures together, we conclude that the west end of the Weihe Graben, southwest corner of the Ordos, is the most likely earthquake-prone area in future. Secondary risk regions for future strong earthquakes are located on the intersection between the Haiyuan fault and Liupanshan fault in the eastern Tibet, in the Yinchuan Graben and southwest of Hohhot around the Ordos Block. Therefore, this work may be significant for predicting earthquake risk and assessment of seismic hazard. •Strain rates are calculated using updated GPS data.•Earthquake potential is obtained based on strain rates and seismicity.•High-risk area is the west end of the Weihe Graben, southwest corner of the Ordos.