Image of seismological anomaly before the February 18, 2020 Changqing M4.1 magnitude earthquake

Abstract

An earthquake of magnitude M4.1 occurred in Changqing County, Shandong Province (36.46°N, 116.65°E) on February 18, 2020. In this paper, we found from the image analysis of seismic activity and wave velocity ratio calculation before this earthquake that the magnitude M4.1 (No special markings on the magnitude of the earthquake: M for magnitude 5 (including magnitude 5) and above, M L for below magnitude 5) in the 1-year scale before the Changqing M4.1 earthquake, inland Shandong and In the Bohai Sea, there is an orderly distribution of magnitude 2 earthquakes, multiple small earthquake sequences, a concentration with active of magnitude 3 earthquakes, the Changdao “earthquake window” “open” several times, and an abnormally low value of wave velocity ratio etc. Phenomena.