Magnitude Estimation Based on Integrated Amplitude and Frequency Content of the InitialPWave in Earthquake Early Warning Applied to Tehran, Iran (original) (raw)

2017, Bulletin of the Seismological Society of America

To optimize magnitude estimation for the earthquake early warning system around the Tehran region, different amplitude-and frequency-based parameters, that is, predominant period (τ max p), characteristic period (τ c), log-average period (τ log), and peak displacement (P d) were analyzed in this article. All parameters were calculated directly from seismic records, with an epicentral distance less than 150 km, and within the initial 3 s of the P waves. The analysis of earthquakes in the 2:4 < M L < 4:9 magnitude range verified that the result of τ max p showed a consistent trend as compared with the global observations, and provided a robust estimate of magnitude for the dataset used in this research. In comparison with worldwide observations, the calculated P d and τ c were underestimated, and there was no scaling relationship with the τ log parameter. When combined with the global observations from Japan, Taiwan, and Italy, the results of P d and τ c for the Tehran region produced optimized results.