Through tectonic and sedimentary interpretation, using two-dimensional seismic lines combining with geological data and well logs, the tectonic characteristics, evolution and genetic relationship of Qujing, Yuezhou, and Luliang basins locating in the fold zone of north-eastern Yunnan Province were discussed, and the effect of tectonic reverse during the Late Oligocene and the end of Pliocene on the accumulation elements of biogenic gas was analysed. The results show that as a result of tectonic reverse of the Late Oligocene, the over-consumption of the organic matters in Caijiachong Formation by organic maturation and hydrocarbon generation or biogas generation was significantly avoided. It ensured the continuous-effective biogenic gas formation providing to the biogas accumulations since Quaternary. The tectonic reverse in the end of Pliocene made the essential elements for the process of biogas accumulation to be placed effectively in tune and space, and controlled forming of the biogas reservoir. The middle fault-dowenwarp belt and its transition region with the fault-fold belt and slope belt are the favorite prospecting areas of biogas reservoirs in the basin.%利用二维地震测线,结合地质和钻井等资料,通过开展详细的构造和沉积解释,分析滇东北褶皱带上的曲靖、越州和陆良3个残余型陆相沉积盆地的构造特征、形成演化和成因联系,特别对渐新世末和上新世末2期重要的构造反转进行较系统地综合研究,分析构造反转活动对生物气成藏条件的控制作用.研究结果表明:渐新世末的构造反转避免了蔡家冲组沉积有机质的大量消耗,促使了蔡家冲组主力烃源岩的二次产气,保障了第四纪以来生物气成藏的有机物质和气源的持续供给;上新世末的构造反转控制了生物气成藏要素的有利时空配置,控制了滇东北新生代盆地生物气藏的形成.中央断凹带及其与断褶带和斜坡带的过渡区带具有良好的生物气生成、运聚和保存条件,为生物气藏富集区带.
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