Abstract The Yola Sub-basin represents the lower portion of the bifurcated Upper Benue Trough, whose origin has been linked to the opening of the Atlantic Ocean in the Mesozoic. The sub-basin fill consists predominantly of siliciclastic and carbonate deposits, the ages of which have remained controversial until now. This work employs field observations integrated with palynostratigraphy to refine the stratigraphy of these Upper Cretaceous deposits. We delineate five palynozones, spanning the upper Albian–Cenomanian, middle Cenomanian, upper Cenomanian, Turonian and Coniacian–Santonian. This palynology indicates that rocks previously thought to be Turonian are in fact Cenomanian. Further, the species Florentinia berran, Florentinia khaldunii, and Subtilisphaera senegalensis are all low latitude dinocysts that previously have only been reported from the Tethyan realm. Their presence here, together with the sedimentology, implies that there was an influx of Tethyan waters into the epeiric sea of the Benue Trough in the Cenomanian. The collective sedimentary and palynological evidence indicates that the Cenomanian transgression was well established in the Yola Sub-basin, and more broadly in the Upper Benue Trough, connecting Tethys with the Gulf of Guinea.

中文翻译：

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贝努埃海槽是否在塞诺曼阶将几内亚湾与特提斯洋连接起来？约拉盆地孢粉地层学的新证据

摘要 Yola 盆地代表分叉的上贝努埃海槽的下部，其起源与中生代大西洋的开放有关。次盆地充填主要由硅质碎屑和碳酸盐沉积物组成，其年代至今仍有争议。这项工作采用野外观测与孢粉地层学相结合来完善这些上白垩统矿床的地层学。我们描绘了五个 palynozones，跨越上阿尔比 - 森诺曼阶、中森诺曼阶、上森诺曼阶、图伦阶和科尼亚克阶 - 桑托阶。这种孢粉学表明以前被认为是土伦阶的岩石实际上是森诺曼阶的。此外，Florentinia berran、Florentinia khaldunii、Subtilisphaera senegalensis 和 Subtilisphaera senegalensis 都是以前仅在特提斯王国报道过的低纬度双胞藻。它们在这里的存在，连同沉积学，意味着特提斯的海水涌入了森诺曼阶的贝努埃海槽的表皮海。综合沉积和孢粉学证据表明，Cenomanian 海侵在 Yola 次盆地，更广泛地在上贝努埃海槽中建立，连接特提斯和几内亚湾。