通过强震震例阐述了重力观测在地震预测中的作用，分析了强震震间期与同震及震后重力场变化特征、区域重力场变化及其与强震活动的关系。强震前区域重力场出现大范围的有序性变化，震源区附近产生与地震孕育发生有关的局部重力异常区，并沿区域主要发震构造断裂带出现显著的重力变化梯度带；强震一般发生在重力变化高梯度带转弯附近或重力变化四象限分布特征中心附近；重力场动态变化图像能够较清晰地反映强震孕育、发展、调整过程的重力变化信息，并基于震例提出了强震震前重力变化的“场-源-带”基本模式。最后，提出我国重力监测预报发展中仍存在的问题，并对利用重力监测资料开展地震预测预报研究进行了展望。

In this paper,we take some examples of strong earthquakes as case studies to discuss the application of gravity observation in earthquake prediction in the period of earthquake preparation,co-seismic and post-seismic stages through study of the variation characteristics of gravity field,regional gravity field and its relationship with strong earthquake activity. Before the strong earthquake,the regional gravity field shows orderly change in a large range. The local gravity anomaly area related to the earthquake preparation is generated near the source area,and a significant gravity change gradient belt appears along the main seismogenic structural fault zone in the area. The strong earthquake generally occurs near the turning of the high gradient belt of gravity field change or the four quadrant distribution characteristic center. The dynamic variation image of gravity field can clearly reflects the information of gravity change in the process of strong earthquake preparation,development and adjustment. Based on the study of earthquake cases,the basic model of “field-source-belt” of gravity change before strong earthquake is put forward. Finally,the problems in the development of gravity monitoring and prediction in China are pointed out,and the prospect of using gravity monitoring data to carry out earthquake prediction and prediction research is discussed.

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国家自然科学基金（41874092、41674018、61627824）、国家重点研发计划项目（2018YFC1503305）共同资助