| Through a brief review of the principles and methodology in determining potential earthquake source in China, as well as discussions on some related essential problems, it is concluded out that studies of the characteristics of seismogenic structure play an important role in delineation of potential earthquake source and in determination of its parameters of seismic activity. More attention should be paid to deeper and further studies on the characteristics of seismogenic structure itself and its application in the future.Formulation of the time limit of identifying active fault and seismogenic structures must be based both on the scientific and engineering safety considerations. Since the time limit is still an unsolved issue, detailed studies on this issue was performed in this paper based on discuss on the widely tectonic events in China continent since late Quaternary. It is pointed out at the first time in this paper that the so-called "Longjie" tectonic event, which occurred in the late stage of Late Pleistocene, exist not only in southwestern China, but also in overall China continent. This tectonic deformation in overall China continent entered a new stage after this event, and the general tectonic properties and active level have changed little since then. Moreover, the occurrence time of this event remains a little different in different regions, in which the major event occurred in about 30,000 years B.P. in western, northeastern and north China, but about 45,000 to 50,000 years B.P. in southern coastal China. In seismic hazard assessment for general engineering sites, it is applicable to take the time limit mentioned above as the time base for identifying active faults and related seismogenic structures. However, for particularly important engineering sites, such as those of nuclear powers and large hydropowes, it is necessary to take 100,000 to 150,000 years B.P. as the time base in safety consideration.The recurrence behavior of the large earthquakes on seismogenic structure in the intraplate of China continent is very complicated. On the base of study of quasi-periodical characteristic behavior, time predictable behavior, and cascade behavior of the earthquake recurrence along active faults, a comprehensive method is proposed to apply above recurrence models in the current seismic risk analysis framework in China. The results of this study are somewhat different from that of applying the parameters of the potential earthquake sources for newly published Seismic Motion Map of China. For example, under the consideration of quasi-periodical characteristic model, the PGA(peak ground acceleration) value with 10% probability of exceedance in 50 years of this study is about 8% to 70% in difference to that of newly published Seismic Motion Map of China. Under the consideration of low frequency factor, the PGA value is about 8% to 9% lower. Under the consideration of time predictable model, the PGA value difference can vary about 20%. Under the consideration of cascade model, the distribution of PGA value changes in certain degree, and the difference of the PGA value varies largely. The amount of above varieties is closelyrelated with the characteristics of earthquake recurrence on active fault. Therefore, it is critical to take earthquake recurrence behavior of seismogenic fault into consideration in seismic risk analysis..A statistical analysis was performed to study earthquake distribution along 54 active faults (segments) in China. It is found that the probability density of earthquake distribution along the seismogenic faults can be stated asp(x) = 1.0125exp(-3.226x2)This model is suitable for the potential earthquake source with single seismogenic structure, and can be utilized to correct the probability density of maximum earthquake occurrence. The utilization of inhomogeneous model has certain effect on seismic risk analysis, especially for the potential earthquake source with a high magnitude and high reoccurrence rate. Taking Tangyin potential earthquake source as an example, with 10%...
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