Rapid report of the 8 January 2022 ​MS 6.9 Menyuan earthquake, Qinghai, China

• DOI: 10.1016/j.eqrea.2022.100113
• Publication Date: 2022-01-30T00:38:45Z
• Authors: Hongfeng Yang; Dun Wang; Rumeng Guo; Mengyu Xie; Yang Zang; Yue Wang; Qiang Yao; Chuang Cheng; Yanru An; Yingying Zhang
• Keywords: Epicenter; Mercalli intensity scale

The MS 6.9 Menyuan earthquake in Qinghai Province, west China is the largest by far 2022. occurs a tectonically active region, with background b-value of 0.87 within 100 ​km epicenter that we derived from unified catalog produced Earthquake Networks Center since late 2008. Field surveys have revealed surface ruptures extending 22 along strike, maximum ground displacement 2.1 ​m. We construct finite fault model constraints InSAR observations, which showed multiple segments during earthquake. major slip asperity confined 10 at depth, 3.5 Near real-time back-projection results coseismic radiation indicate northwest propagating rupture lasted for ∼10 ​s. Intensity estimates show up to Mercalli scale IX near ruptured area, consistent instrumental measurements and observations field surveys. Aftershock locations (up January 21, 2022) exhibit two segments, ∼20 depth. one reaches 5.3, locating eastern end aftershock zone. Although location approximate magnitude mainshock had been indicated previous studies based on paleoearthquake records seismic gap, as well estimated stressing rate faults, significant surface-breaching leads severe damage high-speed railway system, poses challenge accurately assessing hazards risks, thus demands further investigations behaviors crustal earthquakes.