本文利用两种常用的NGR和MGR模型，对我国大陆地区1970年以来各地震带的震级一频度关系和震级上限进行了修定。结果表明，MGR模型能很好地描述非线性的震级．频度关系，因此该模型更适合于我国大陆地区各地震带M13．0以上地震的震级-频度关系，用MGR方法拟合确定震级上限时，样本量越高拟合的结果越准确。

In this paper, modification on magnitude frequency relation and magnitude limit determination based on NGR and MGR （commonly used models） are studied in various seismic zones in Chinese mainland since 1970. The results indicate that the MGR model can be used to describe the nonlinear frequency relations so that the magnitude frequency relations of MGR model is more suitable to magnitude frequency relation of ML 〉3.0 earthquakes of various seismic zones in Chinese mainland. The result of the fitting high sample size of the magnitude limit determination based MGR model is accurate.[著者文摘]

宁夏回族自治区攻关项目“宁夏及邻区中强以上地震震后趋势判定及强余震的预测研究”（102164170）资助