东风港油田沙三上浊积扇的“叠置扇”沉积特征

陆相断陷盆地浊积扇体的发育受构造运动、湖平面变化、沉积物供给、古地貌等多因素的控制.以断陷湖盆济阳坳陷车镇凹陷缓坡带东风港油田为例,在系统调研和大量实际工作的基础上,针对陆相浊积扇规模小、分布分散、呈多层薄层状、识别和预测十分困难的特征,建立断陷湖盆缓坡带浊积扇沉积的"叠置扇模式"."叠置扇模式"具体表现为"垂向叠置,扇上有扇;侧向迁移,扇外有扇".在油气勘探中,根据"叠置扇模式"的发育特征和控制要素分析,可以更好地预测有利勘探开发目标.济阳坳陷车镇凹陷东风港油田大量小型浊积扇的成功勘探开发充分证明了这一点.

Depositional mode of turbidite fans in upper sub-member of Sha-3 in Dongfenggang Oilfield

The development of turbidite fans in faulted lake basin is controlled by external factors,such as tectonic setting,lake level fluctuation,sediment supply rate and paleogeomorphology.Generally,the turbidite fans are of small scale and disperse distribution and they are composed of thin layers.So it is difficult to recognize these turbidite fans.Dongfenggang Oilfield locates in gentle slope zone of Chezhen Sag in Jiyang Depression which is in faulted lake basin,in which turbidite fans are developed.Taking the oilfield as an example,a development mode of turbidite fans in gentle slope of faulted lake basin-" superimposed fan" is put forward based on systematic investigation and a lot of practice.The superimposed fan mode is featured by " fan bodies superimposing vertically,overlaying on each other,and moving laterally,standing side by side".The study of development characters and the analysis of control factors of the superimposed fan can provide guidance for exploration activity and searching favorable exploration area,which are verified in the successful exploration and development of a lot of turbidite fans in Dongfenggang Oilfield.