车古20潜山主要断层垂向封闭性评价

Evaluation on Vertical Sealing Nature of Main Faults in Chegu-20Burried Hill

在车古20潜山断层发育及演化特征研究的基础上,通过断层垂向封闭机理及影响因素分析,指出断层面压力和断裂带泥质含量是影响断层垂向封闭性的主要因素.利用抗压模拟实验结果确定出泥岩塑性变形极限,利用断移地层岩性及断距建立了一套预测断裂带砂泥含量的方法.在此基础上,对车古20潜山主要断层在C-P-Es4垂向封闭性进行了评价。除断层F23、F42和F1在298测线及车古203—车古20—车古201井一线不具垂向封闭性外,其余断层在C-P-Es4皆具垂向封闭性,这是该区油气聚集与保存的重要条件.

The faults development and evolution features in Chegu-20burried hill as well as their vertical sealing mechanisms and affected factors are analyzed.The main factors controlling vertical sealing faults are the pressure exerted on fault plane and the shale content.From the modeling result of compressive experiment,the plastically deformed limitation of mudstone is presented,and the method for prediction of sandy and shale contents in fault zone is established by its lithology and fault throw.Based on these,the vertical sealing nature of Chegu-20burried hill in Carboniferous-Permian to Paleogene are evaluated.It is pointed out that the faults are all characterized by vertical sealing nature in C-P to Es4except for faults F23,F42and F1in Line-298and a-long Chegu-203-Chegu-20-Chegu-201.They show that this area possesses significant conditions for hydrocarbon accumulation and preservation.