延安地区上三叠统长6期沉积特征及其演化

Sedimentary characteristics and evolution during Upper Triassic Chang 6 stage in Yan'an Area

通过对川口油田测井曲线和岩心分析,总结了延安地区上三叠统长6期沉积微相特征,建立了长6期岩性和测井曲线的响应模式。再结合分析沉积的演化过程、电性和物性特征、骨架砂体的几何形态和沉积演变,得出该地区沉积相和演化模式。认为从长64到长61期沉积环境为湖泊、三角洲前缘、三角洲平原亚相到河流相。长61、长62是主力储层,其物性最好。

According to analysis results of logging curve and cores in Chuankou oilfield, the study area＇ s rock-logging model of Chang 6 is established. Moreover, the sedimentary facies and evolution model are also established through analyzing sedimentary evolution processes, logging and physical characters, the geometry form of sandbody framework. A conclusion is got that the facies of lake, delta front and plain and river appear in turn. The intervals of Chang 61 and Chang 62 are the main oil-bearing intervals and their characters are the best among 4 oil-bearing intervals of Chang 6.