China (CHN)

Authors:

M. Gao, G. Chen, F. Xie, X. Xu, X. Li, Y. Yu, S. Li, B. Zhou, H. Pan, Y. Lu, F. Zhao, J. Wu

Summary

The Global Hazard Mosaic coverage of China is based on the 2015 seismic hazard model of China (GB18306-2015), developed by the Institute of Geophysics of the China Earthquake Administration (CEA). The model has been translated from its original format into the OpenQuake (OQ) engine within a collaboration between the CEA, the Swiss Seismological Service, the Swiss Federal Institute of Technology, and GEM.

Information about the OQ model versions and input files can be found on the Results and Dissemination page.

Interactive Viewer

The viewer below depicts the seismic sources and hazard results in terms of PGA for a return period of 475 years. Click on the menu in the upper right corner to select the layer.

viewer_legend

Tectonic overview

China sits at the western edge of Eurasia, and faulting and tectonics in China are determined by the interaction of Eurasia with the neighboring India and the plates and microplates of the western Pacific and Indochina areas. The most active regions are in the west, where the Indo-Asian collision causes faulting in the Tibetan plateau and Tien Shan ranges; this belt of deformation continues through Mongolia. Though the Tibetan plateau is very sparsely populated and the attenuation of seismic waves is great, the eastern margins of this deformation zone abut the densely populated Sichuan Basin and adjacent areas; seismic activity here is among the most deadly on earth. Slow faulting extends from eastern Tibet to the northeast into the Gulf of Bohai near Beijing, and possibly north to the border with Russia along the Tanlu Fault Zone. In the southeast, strike-slip faults radiate from Eastern Tibet through Yunnan, and rapid contractional deformation related to the collision of the Philippine Sea plate with China cuts through Taiwan.

Basic Datasets

The datasets used for developing the hazard model are described in the references below.

Hazard Model

Seismic Source Characterisation

The seismic source characterisation (SSC) consists entirely of zones of distributed seismicity. The SSM is characterised by three levels of delineation. The largest zones divide the entire region into 29 seismic belts. These are subdivided into 77 smaller zones used to model background seismicity. The smallest level of zonation consists 1199 zones encompasing active faults. Using this approach, background seismicity as well as seismicity associated with active tectonic faults are modeled with distributed seismicity.

The OQ implementation uses the Area Source typology to model zones of distributed seismicity. The OQ sources are depicted in the interactive viewer.

Epistemic Uncertainties

Epistemic uncertainties of the SSM are not considered.

Ground Motion Characterisation

The table below shows the ground motion characterisation (GMC), which is comprised of a set of ground motion prediction equations (GMPEs). The GMM for China distinguishes between four main tectonic regions: Active Shallow Crust, Stable Shallow Crust, Eastern, and Tibetan.

Active Shallow Crust Weight
YuEtAl2013Ms 1.0
Stable Shallow Crust Weight
YuEtAl2013MsStable 1.0
Eastern Weight
YuEtAl2013MsEastern 1.0
Tibetan Weight
YuEtAl2013MsTibet 1.0

Results

Hazard curves were computed with the OQ engine for peak ground acceleration (PGA) and spectral acceleration (SA) at 0.2s, 0.5s, 1.0s, and 2s. The computation was performed on a grid of 119147 sites (spaced at approximately 10 km) with reference soil conditions with shear wave velocity in the upper 30 meters (Vs30) of 760-800 m/s.

The hazard map for PGA corresponding to a 10% probability of exceedance in 50 years (475 year return period), can be seen using the interactive viewer. For a more comprehensive set of hazard and risk results, please see the GEM Visualization Tools.

References

K. Chen, M. Gao, "Discussion on Relationship between Anti-great earthquake and the Ground Motion with a Low Probability of Exceedance", Technology for earthquake disaster prevention, 2013,8(1), DOI:10.11899/zzfy20130104.

General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, China National Standardization Management Committee. 2015. China seismic zoning map (in Chinese). GB 18306-2015.

H. Pan et al., "The Earthquake Activity Model and Seismicity Parameters in the New Seismic Hazard Map of China", Technology for earthquake disaster prevention, 2013,8(1), DOI:10.11899/zzfy20130102

F. Xie et al., "Large Earthquake Recurrent Intervals along Active Faults in Mainland China",Technology for earthquake disaster prevention, 2013,8(1), DOI:10.11899/zzfy20130101

Y. Yu et al., "Development of Ground Motion Attenuation Relations for the New Seismic Hazard Map of China", Technology for earthquake disaster prevention, 2013,8(1), DOI:10.11899/zzfy20130103

B. Zhou et al., "The Technical Highlights in Identifying the Potential Seismic Sources for the Update of National Seismic Zoning Map of China", Technology for earthquake disaster prevention, 2013,8(2), DOI:10.11899/zzfy20130201