摘要
本文对泾阳MS4.8级地震前后陕西关中地区流动重力观测资料和有关断裂垂直形变资料进行了分析研究。结果表明:①波速比高值区很可能存在地下深部地幔物质的入侵,由此引发地震和重力场的显著下降;②用震源机制解和GPS所作的运动矢量图可以较好地解释泾阳地震前后重力场时空演化特征及有关断裂活动——其变化是北西向剪切应力带作用的结果。
The mobile gravity data and fault vertical deformation data before and after the Jingyang Ms4.8 earthquake in Guanzhong region of Shaanxi province are systematically analyzed. According to the results we have the following understanding. First, the high zone of VP/VS ratio may reflect deep mantle material invasion which may conduce the earthquake and result in obvious gravity field decrease. Second, the characteristics of gravity field spatio-temporal variation and fault activity before and after the earthquake due to the effect of NW shear stress field can be explained by the focal mechanism solution and vector diagram of ground movement obtained by GPS measurement.
出处
《灾害学》
CSCD
2006年第1期73-77,共5页
Journal of Catastrophology
基金
陕西省地震局科研课题基金(2005-01)
关键词
关中地区
泾阳地震
重力变化
断裂活动
Guanzhong region
Jingyang earthquake
gravity variation
fault activity
