CHARACTERIZATION AND ANALYSIS OF GRAVITY FIELD CHANGES BEFORE AND AFTER THE JANUARY 23,2024 Wushi MS7.1 EARTHQUAKE
Using the mobile gravity observation data after Wushi MS7.1 earthquake in the South Tianshan area,the gravity field changes in the South Tianshan area before and after Wushi MS7.1 earthquake were obtained,and the 1-year and multi-year scale gravity changes before and after the earthquake in the area were studied.The results show that after the Wushi earthquake,the zero iso-line of gravity change passes through the epicenter area and a high gradient zone of gravity change appears.In the area where the zero contour of gravity change appears,the material density is under-going a transition process of increasing and decreasing.The difference in material increase and de-crease leads to strong movement and energy accumulation.The gravity anomaly before strong earth-quakes may last for a long time,and there may be a small change in the gravity field.Therefore,when extracting and analyzing the gravity anomaly signal before strong earthquakes,it is necessary to consider the gravity observation data with a long time span.The mobile gravity data observed after the earthquake can better reflect the stress release characteristics of the seismogenic fault,which is helpful to analyze the development trend of aftershocks.
Southern TianshanWushi MS7.1 earthquakeBayesian methodGravity field varia-tion
万方数据
