延吉盆地断层侧向封闭性研究

Research on Lateral Sealing of Fault in Yanji Basin

延吉盆地勘探过程中,多数圈闭上钻井有油气显示,但见工业油气流井甚少,究其原因,盆地中圈闭大多是断块、断鼻和断背斜,断层封闭性是圈闭是否成功的关键。利用断层两盘砂泥对接概率计算模拟的方法,研究了延吉盆地大拉子组一、二段断层的侧向封闭性,认为延吉盆地大拉子组一、二段断层侧向封闭性是很复杂的,盆地边界的断层侧向封闭性较好的断层较少,只有盆地的边界断层较好,东区断层的封闭性明显好于西区。断层侧向封闭控制了天然气的聚集成藏。

During the oil and gas development of Yanji basin, most traps drilled had oil and gas show, but very few commercial oil and gas flow wells were found. Because major traps are mainly fault, blocks, fault noses and fault anticlines in basin, fault sealing is the key to control the oil or gas-bearing of traps. We utilized simulation calculation method of butted joint probability of sand and shale between fault walls, and researched the lateral sealing of faults in first and second member of Dalazi formation in Yanji basin. We think that the lateral sealing of faults in first and second member of Dalazi formation is very complex and very few iaults have good lateral sealing, and lateral sealing of the faults on the border of basin is quite good. The fault sealing in the east of basin is better than that in the west of basin. The lateral sealing of faults controls the gas accumulating and reservoir-forming.