【摘要】 雷口坡组是四川盆地重要的含气层系。根据露头、岩心、分析化验、录井、测井、地震等资料的综合分析认为,受古地质背景和海平面升降旋回的控制,四川盆地在中三叠世雷口坡期是一个水体浅、盐度大、范围广阔的障壁型碳酸盐岩台地,由于受周边古隆起和盆内水下古隆起障壁作用的限制,台地内外海水交流不畅,台地内水动力条件偏弱、生物不繁盛、干旱气候为主是其基本特征。雷口坡组在平面上表现为自西向东台地边缘—潟湖边缘坪(台内滩)—潟湖—潟湖边缘坪(台内滩)—潟湖—混积潮坪的沉积相展布特征,纵向上表现为蒸发岩、白云岩与石灰岩互层的演化特征。绘制了盆地雷口坡期岩相发育演化图。预测盆地西部龙门山白云石化台缘滩、中部泸州—开江水下古隆起及其周边的古地貌高处台内滩和潟湖边缘白云岩坪是有利的储集岩相分布区。更多还原

【Abstract】 Middle Triassic Leikoupo Formation is one of the important gas-bearing strata in Sichuan Basin.On the basis of comprehensive analysis of outcrops,drilled cores,laboratory,well logging and seismic data,it is shown that under control of palaeogeologic setting and eustatic fluctuations,Sichuan Basin was a water-shallow,high salty and wide barriored carbonate platform confined by palaeo-uplifts during Middle Triassic Leikoupo age.The platform was characterized basically by developing intrabasinal barriers,weak hydrodynamism,poor creature and arid climate.Leikoupo Formation beheaves an evolutional distribution of platform edge microfacies,lagoon microfacies,lagoon edge microfacies(platform interior shallow microfacies),lagoon microfacies,lagoon edge microfacies(platform interior shallow microfacies) to transitional microfacies successively from west to east in lateral and the evaporate rock,dolostone interbedded with limestone in longitudinal in the barriered platform.Some Middle Triassic Leikoupo lithofacies development and evolution maps are drawn.It is predicted that the favorable lithofacies for reservoirs develop in the peripheral regions of the barriors including the Longmen Shan Uplift in the west of the basin,and the Luzhou and Kaijiang Uplifts in the south and east of the basin.更多还原