Seismic Activity and Gravity Anomaly Characteristics of Yutian in Xinjiang and Surrounding Regions
Xu Weimin
Chen Shi
Shi Lei
Abstract：The latest model of the gravitational field was used in the analysis of the gravity anomaly characteristics in the Yutian seismic zone and surrounding regions.The layered crustal structure model (Crust1.0)has been applied to obtain the deep tectonic structure around the seismic zone.This epicenter occurred in the steep variations of the crustal thickness.Contrast to the Ms 7.3 earthquake in 2008 in this region,although these two epicenter were located in different 3-D spaces,they are closely related to the changes in the deep crustal structures.Besides,based on the statistical analysis of the relationship between the seismicity of historical earthquakes (Ms ≥5.0)and three different gravity anomalies,we found that the free-air gravity anomalies in the seismic zone are in an obvious linear cor-relation to the topography,while the Bouguer anomaly and isostatic anomaly are distinctly different with the topography.In addition, the total gorizontal gradient (HGM)of the anomalies were calculated and the analytical signal (ASL)was plotted,which suggest that the gradient values are more distinctly correlated.The results show that a significant statistical characteristic exists between the activi-ties of the strong earthquakes (Ms ≥7.0)and the gravity anomalies,which may be related to the mass uneven distribution of the deep structure which caused the gravity anomaly.
Keywords：Yutian earthquakeSeismic activitygravity anomalycrust modelstatistical characteristicsearthquake
Publication Date：2014-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：11( 1831-1841 )