利用陕甘川地区2016—2018年5期流动重力观测资料，分析了陕西宁强M_S5.3地震前半年和1年尺度的重力场变化特征。同时采用小波多尺度分解方法，对宁强M_S5.3地震震中区的布格重力异常进行1～4阶小波分解，并对1～4阶小波细节图像进行分析。研究结果表明：①宁强M_S5.3地震重力场呈现“正向变化—正向减弱—负向变化—负向减弱”演化过程，震前重力场呈现四象限分布特征，震中位于鞍部位置，符合走滑型地震特征；②布格重力异常2～3阶小波细节对宁强M_S5.3地震孕震特征有较好的反映，对应的场源深度为10～15km，与本次地震震源深度11km有较好的对应关系。

Based on the observation data of relative gravity in Shaanxi-Gansu-Sichuan region from the year 2016 to 2018, we analyzed the variation characteristics of gravity field at a time scale of 0.5~1 year before Ningqiang M_S5.3 earthquake. We also decomposed the Bouguer gravity anomaly in the epicentral area of Ningqiang M_S5.3 earthquake by 1~4 order wavelet, and analyzed the detail image of 1~4 order wavelet. The research results show that:① The gravity field of Ningqiang M_S5.3 earthquake displays the evolution process pattern of "positive variation-positive weakening-negative variation-negative weakening". Before the earthquake, the gravity field presents the characteristics of four quadrant distribution, and the epicenter is located in the saddle position, which implies the characteristics of strike slip earthquake. ② The 2nd to 3rd order wavelet details of Bouguer gravity anomaly have a good correlation on the seismogenic characteristics of Ningqiang M_S5.3 earthquake. The corresponding field source depth of the 2nd to 3rd order wavelet details is 10~15km, which has a good corresponding relationship with the focal depth of this earthquake.

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陕西省自然科学基础研究计划青年项目（2021JQ-962）、2019年度“三结合”课题（3JH-201902006）、陕西省启航与创新基金（QC201717）共同资助