渤海湾盆地新生代晚期断层活动与新近系油气富集关系

根据渤海湾盆地新近系油气分布特点及成藏地质背景，对新近纪-第四纪的断层活动性与油气富集特征及其相互关系进行探讨。研究表明，新生代断层晚期活动影响各成油组合油气宏观分布，控制新近系油气富集类型及富集区带。断层差异活动对油气富集的影响可用差异系数（FDC）表征，断层在主生排烃早中期活动较强、晚期活动较弱对油气聚集最为有利。综合考虑断层活动速率及差异系数，将断层控油级别分为Ⅰ，Ⅱ和Ⅲ类，Ⅰ和Ⅱ类断层分布多的区带新近系油气较为富集，其活动速率及差异系数相对较大，Ⅲ类断层分布多的区带新近系油气富集程度差，其活动速率及差异系数相对较小。断层差异活动影响油气富集，控油级别决定油气富集程度。

Late Cenozoic Faulting activities and their influence upon hydrocarbon accumulations in the Neogene in Bohai Bay Basin

Neogene-Quaternay faulting activities and their influence upon hydrocarbon accumulations in Bohai Bay Basin were analyzed based on hydrocarbon distribution characteristics and geological settings.It shows that the late faulting activity influenced the macroscopic distribution of the hydrocarbon accumulation assemblage and controlled the Neogene oil and gas enriched types and enriched belts of different depressions.Effect of faults different activity on hydrocarbon accumulation can be characterizedby fault activity difference coefficient(FDC).When the early and mid-generation and expulsion of hydrocarbon, the fault activity is strong and when late generation and expulsion of hydrocarbon the fault activity is weak, that is most favorable for hydrocarbon accumulation.Based on fault activity rate and FDC, we categorized the faults into Ⅰ, Ⅱ and Ⅲ kinds in terms of their controlling ability on oil and gas accumulation.The first two types with faster fault activity rate and larger FDCs, were distributed in places where oil and gas are highly enriched in the Neogene and the last type with slower fault activity rate and small FDC was in places where oil and gas enrichment is poor in the Neogene.Based on the understanding, we propose that differences in faulting activities controlled oil and gas accumulations and the types of faults determined the level of oil and gas enrichment.