Determination and Comparison of M _L, M _{S_BB}, m _B, M _Wp, M _ww, M _dt, and M (GNSS) for the 22 May 2021 M7.4 Madoi, Qianghai, China Earthquake

Abstract

The 2021 Madoi M7.4 Earthquake in Qinghai is a major earthquake that occurred in the Bajankara Block of Qinghai-Tibet Plateau in the past 30 years, which spatially filled the seismogenic gap in the eastern section of the northern boundary of the block. Here we determined the values of M _L, M _{S_BB}, m _B, M _Wp, M _WW, M _dt, and M (GNSS) by abundant regional and global seismic and geodetic observations, which is 6.61, 7.43, 7.18, 7.33, 7.43, 7.38, and 7.4, respectively. To compare the time efficiency and stability of different magnitude scales, we generated a real-time environment, to iteratively determine the magnitudes over elapsed times. Some methods such as m _B, M _SBB, M _Wp gave considerable variations of as large as 0.5 units for the determined magnitudes with elapsed time, as more data were included. Others such as M _WW and M _dt were very stable with increasing data over time. The systematic calculations of various magnitude scales in this study quantitively evaluated the stability and accuracy of those methods, shading light on the adaptability and applicability of different magnitude scales.

Keywords

the 2021 Madoi Earthquake / earthquake magnitude / magnitude scale / earthquakes

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