Earthquake Information:

11. What is the effectiveness of the "Strong Ground Motion Seismic Network"?

The geological conditions in Taiwan are enormously complicated, and the vibration characteristics are also very different in each region. Therefore it is inappropriate to engage in earthquake-resistant construction design by taking select local earthquake frequency spectra and widely utilizing this limited data in other areas with different geological conditions. For instance, Taipei basin is located in a lacustrine deposit basin, piled up with thick and solidifying layers of weak, loose soil. These geological conditions make the basin conducive to produce a magnifying effect during certain seismic waves. On May 20, 1986, an earthquake occurred near Hualien, with a magnitude of 6.2. In the same year, on November 15, there was another earthquake which occurred in the same area with a magnitude of 6.8. Although these epicenters were near Hualien, the major areas of disaster occurred in Taipei. It is therefore very important to understand that different geological conditions can result in different geological-seismic effects. Even within the Taipei basin, different locations also experience great differences in ground movement.

The information collected by the Strong Ground Motion Seismic Network can provide a standard for the review on current earthquake-resistant construction engineering. Hopefully the modified construction design will conform to economic and safety requirements for the future. As a result, the Central Weather Bureau has made a great effort to establish the Strong Ground Motion Seismic Network beginning in 1992. The purpose of this network is to collect long-term data on strong ground motion observed in each metropolitan area in Taiwan.

10. What is the definition of "the observation of strong ground motion"?  12. What is "the theory of plate tectonics"?