- © 2011 by the Seismological Society of America
The Beijing capital region (36°N–42°N, 113.5°E–120°E) is located in northern China and includes Beijing City, Tianjin City, and Hebei Province. This region of critical economic and cultural importance is threatened by large earthquakes. Historical earthquake records show that this region has been struck by many strong-to-great earthquakes (see Figure 1), with magnitudes up to M 8 (the 1679 Sanhe-Pinggu earthquake). In the 20th century, the 1976 M 7.8 Tangshan earthquake caused more than 240,000 fatalities and uncountable economic losses. Developing an earthquake early warning system (EEWS) in this region is therefore of great importance and necessity. This necessity was dramatically highlighted by the disastrous Wenchuan earthquake in 2008. After the Wenchuan earthquake, a news media report that Japanese seismologists could “predict” an earthquake several seconds before its occurrence caused a lot of discussion in China. This was actually a misunderstanding of the EEWS performance during the Iwate-Miyagi Nairiku earthquake on 14 June 2008, about one month after the Wenchuan earthquake, but the importance of EEWS in earthquake disaster mitigation has become more and more evident. Accordingly, the China Earthquake Administration (CEA) was motivated to configure a nationwide EEWS.
EEW systems have recently been developed in many countries and regions, such as Japan (Nakamura 1988, 1996, 2004; Horiuchi et al. 2005; Nakamura and Saita 2007; Hoshiba et al. 2008; Brown et al. 2009; Kamigaichi et al. 2009), southern California (Allen and Kanamori 2003; Wu et al. 2007; Böse et al. 2008; Allen, Brown et al. 2009; Böse et al. 2009; Cua et al. 2009; Köhler et al. 2009), Mexico (Espinosa-Aranda et al. 1995; Goltz and Flores 1997; Espinosa-Aranda et al. 2009; Suárez et al. 2009), Taiwan (Wu and Teng 2002; Hsiao et al. 2009 …