东濮-莘县凹陷兰聊断裂活动及对沉积的控制

Lanliao faulting activities and their control over sedimentation in the Dongpu-Xinxian Sag

综合地震和钻井资料,运用断层活动速率法研究兰聊断裂时空演化规律,并重点剖析同沉积期断裂活动对东濮-莘县凹陷地层厚度、空间展布及沉积体系发育的控制作用。研究表明:兰聊断裂在空间上显示出较强的分段性活动特征,东濮凹陷段(南段)活动性整体强于莘县凹陷段(北段),时间上呈现为幕式特征,具体表现为较弱—最强—较强—最弱的变化趋势;裂陷沉积期,兰聊断裂活动性强的位置对应于沉降沉积中心,地层沉降量与兰聊断裂的活动速率具有正相关性;同沉积断裂活动对盆地沉积充填背景和沉积体系类型具有明显的控制作用,构造活动强度与沉积作用相关性高的地区是隐蔽油气藏勘探有利区。该研究可为断陷湖区油气勘探提供地质依据。

By using seismic data and drilling data jointly, rules in spatial-time evolution of the Lanliao Fault have been determined through application of fault activity velocity method. At the same time, studies were performed to determine control of faulting in the same sedimentary period over formation thickness, spatial distribution and devel- opment of the sedimentary system in the Dongpu-Xinxian Sag. Research results show the Lanliao Fault displayed obvious spatial features in intensive activities in different stages. Generally speaking, intensities of activities in the Dongpu Sag Interval （the southern interval ） are stronger than those in the Xinxian Sag Interval （ the northern inter- val ）. As far as time is concerned, these activities have strong stage features represented by the trend of weak-stron- gest-relatively strong-weakest. During the rift sedimentary period, positions with intensive Lanliao faulting activi- ties distributed around the sedimentary center. At the same time, formation settlements are in positive correlation with activities of the Lanliao Fault; Faulting activities in the same sedimentary period may effectively control basin filling background and types of the sedimentary systems. In addition, areas with stronger correlation between intensi- ties of tectonic activities and sedimentation can be seen as favorable zones for exploration of concealed reservoirs. Relevant research results may provide reliable geologic evidences for oil-gas exploration in faulting lake zones.