措勤盆地油气系统研究

Petroleum Systems in Cuoqin Basin

研究措勤盆地的烃源岩、储集层、盖层和圈闭的特征 ,剖析各油气系统的发展演化历史 ,对该盆地的油气远景进行预测 .本区下白垩统川巴组的泥质岩 ,多巴组和郎山组的碳酸盐岩是有效烃源岩 ;川巴组的砂岩 ,多巴组的砂岩和碳酸盐岩以及郎山组的碳酸盐岩是主要的储集层 ;川巴组的泥质岩为局部盖层 ,多巴组和郎山组的碳酸盐岩是区域盖层 .燕山晚期运动为本区的油气聚集提供了有效的圈闭 .本区共划分了 7个油气系统 .根据盆地模拟结果综合分析表明 :措勤盆地最有利的油气区是洞错 -阿苏地区 ,该区的 K1ch- K1ch(!)油气系统是最有利的系统 ;其次是马窖 -门当日阿次地区 ,该区以 K1ch- K1ch(?)油气系统最有利 ;

The characteristics of the hydrocarbon source rocks, reservoir rocks; cap rocks and traps in Cuoqin Basin are studied by the theory of petroleum system. The historical evolution of the petroleum systems is analyzed. The hydrocarbon potential of the basin is predicted. It is shown that, among lower Cretaceous intervals in this area, the mudstone in Chuanba formation, the carbonate in Duoba formation and Langshan formation are effective source rocks; the sandstone in Chuanba formation, the sandstone and carbonate in Duoba formation and the carbonate in Langshan formation are main reservoirs; the mudstone in Chuanba formation is local seal, and the carbonate in Duoba formation and Langshan formation are regional seals. The effective traps for petroleum accumulation were developed mainly in late Yanshan orogeny. Seven petroleum systems are identified in Cuoqin Basin. According to the simulation and analysis results of the basin, it is held that the most favorable area in the basin is Dongcuo-Asu area, and in the area the most favorable system is K 1ch-K 1ch(!) system; the secondary favorable area is Majiao-Mendangrici area, and the K 1ch-K 1ch(?) system is best in the area; Sekacuo-Mamicuo area has rather poor hydrocarbon potential.