Review of the Earthquake Prediction Process and Basis for the 2022 Menyuan MS6.9 Earthquake, Qinghai Province, China

On January 8, 2022, an M_S6.9 earthquake occurred in Menyuan County, Qinghai Province, China. The epicenter was located in the tectonic transition zone between the Lenglongling fault and the Tuolaishan fault on the northeastern Qinghai-Tibet Plateau. Starting from July 2021, based on the increased seismic activity of magnitude 5 or above in the central and northern regions of the Qinghai-Tibet Plateau, as well as a significant increase in the number of short-term geophysical observation anomalies compared to the level before the 2021 Maduo M_S7.4 earthquake, Qinghai Province, it is determined that the evaluation of earthquake trend in this area is between M_S6-7. In November 2022, according to the "Technical Specification for Determining Annual National Critical Earthquake Risk Areas", based on the annual urgency determination results of long-term major earthquake risk sources, anomalous variation of gravity, seismic activity anomalies of a small earthquake, geophysical observation anomalies such as quasi synchronous changes of ground fluid, and comprehensive probability prediction results, it was comprehensively determined that there is a probability of an earthquake with M_S6.0 or so occurring in the central and western sections of the Qilian Mountains seismic belt in 2022. In December 2022, there were new short-term ground fluid anomalies such as the water temperature at Delingha station and the escaped gas radon from groundwater at Xining station in the northeastern Qinghai-Tibet Plateau. Based on the short-term and imminent earthquake tracking technical solutions and analysis strategies in the Gansu-Qinghai region, the comprehensive earthquake prediction result was that there is a probability of an earthquake with M_S6.0 or so occurring in the central and western sections of the Qilian Mountains seismic belt in January 2021.