【摘要】 根据UTCSR发布的GRACE卫星资料,计算了汶川及其周边地区的卫星时变重力场,并利用小波多尺度分析方法对卫星重力场进行分解,得到了反映不同深度的重力场细节和逼近。通过研究各个细节和逼近成分的重力场变化,结合区域构造运动的特点,对GRACE观测的时变重力场及汶川地震的动力机制进行了初步解释和讨论。结果表明,4阶细节和4阶逼近较好地揭示了汶川地区构造形变和深部物质流动引起的重力变化,而且这种震前重力变化特征满足地震孕育发生的条件。更多还原

【Abstract】 The time variable gravity in Wenchuan and its surrounding areas was calculated by using the GRACE data published by UTCSR.Then the multi-scale wavelet analysis was used to decompose the satellite gravity field,therefore,details and approximations reflecting different depth of geological bodies were obtained.By studying changes in the gravity field of every detail and approximation component,combining with the features of regional tectonic movement,a preliminary explanation and discussion on the features of time variable gravity as well as the dynamic mechanism of Wenchuan earthquake was presented.The results show that the change in gravity which caused by the tectonic deformation and deep mass transfer in Wenchuan area is revealed effectively by the fourth-order detail and approximation.Moreover,the features of changes in gravity before earthquake meet the conditions of earthquake preparation and occurrence.更多还原