The Aptian evaporitic transitional sequence (sag phase) of the Brazilian marginal basins records the first connection between the Central and South Atlantic oceans in the equatorial area. During this phase, lacustrine carbonate reservoirs and giant salt deposits developed in the southern basins of Santos and Campos, forming world-class petroleum reservoirs. The sag succession is also well-preserved in the interior rift basins of north-eastern Brazil, where upper Aptian strata are represented by a continuous section. This contribution presents an interpretation of the evolution of a third-order depositional sequence comprising lacustrine limestones, marine siliciclastic facies and evaporite deposits of the intracontinental Araripe Basin. The Lowstand Systems Tract is characterized by fluvial deposits filling accommodation generated during the syn-rift phase. The overlying deposits comprise marine facies with preservation of dinoflagellates and marine ichnotaxa, evidencing marine deposition in bayhead delta settings. The transgressive surface is represented by limestones, including the Konservat–Lagerstätte laminites, onlapping the basement rocks. Above, tide-dominated bay deposits with distinct subtidal, intertidal and supratidal portions are recorded. The Maximum Flooding Surface is a dark shale below foreshore to shoreface facies, marking the beginning of the Highstand Systems Tract, culminating with deposition of evaporites (gypsum and anhydrite). The stratigraphic architecture and palaeocurrents measured in different facies associations suggest that marine waters reached the basin from the south. The data unequivocally records late Aptian marine ingressions of an incipient South Atlantic Ocean over the interior basins of north-eastern Brazil, while lacustrine conditions were still prevailing in the Pre-Salt sag units of the Santos and Campos basins.

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不断演化的陆上海中的混合硅质碎屑-碳酸盐沉积：巴西东北部内陆盆地边缘海洋环境的 Aptian 记录

巴西边缘盆地的 Aptian 蒸发过渡序列（凹陷相）记录了赤道地区中大西洋和南大西洋之间的第一次连接。这一阶段在南部桑托斯盆地和坎波斯盆地发育了湖相碳酸盐岩储层和巨型盐矿，形成了世界一流的油气藏。巴西东北部内部裂谷盆地的凹陷序列也保存完好，上阿普蒂安地层以连续剖面为代表。这一贡献解释了三阶沉积序列的演化，包括陆内阿拉里佩盆地的湖相灰岩、海相硅质碎屑相和蒸发岩沉积物。Lowstand Systems Tract 的特点是在同裂谷阶段产生的河流沉积物填充住所。上覆沉积物包括海相，保留了甲藻和海鱼纲，证明了湾头三角洲环境中的海相沉积。海侵表面以石灰岩为代表，包括Konservat-Lagerstätte层压板，覆盖基底岩石。上面记录了潮下、潮间和潮上部分以潮汐为主的海湾沉积物。最大洪泛面是前滨至滨面相下方的深色页岩，标志着高位系统域的开始，最终沉积有蒸发岩（石膏和硬石膏）。在不同相组合中测量的地层结构和古洋流表明海水从南部到达盆地。数据明确地记录了早期南大西洋在巴西东北部内陆盆地的阿普蒂安晚期海侵，而桑托斯和坎波斯盆地的盐下凹陷单元仍然存在湖泊条件。