As a part of our palynological investigations of the Upper Cretaceous deposits from the Rif Chain, the present study of the dinoflagellate cyst assemblage distribution and palynofacies was carried out in the Bou Lila section, located northeast of the city of Ksar El-Kébir (External Rif, northwestern Morocco). The study focused on the age refinement and interpretation of paleoenvironmental conditions within the basin during the sediment deposition. The analyzed samples are rich in palynomorphs, formed essentially of diverse and well-preserved dinoflagellate cysts, which are associated with phytoclasts and rare microforaminiferal test linings, spores, pollen grains and algae.

The Bou Lila section is assigned to the late Campanian, based on dinoflagellate cyst taxa, whose first appearance datums (FADs) or last appearance datums (LADs) are markers of the late Campanian. These taxa include Areoligera coronata, Areoligera senonensis, Cerodiniuum diebelii, Chatangiella? robusta, Cribroperidinium wilsonii subsp. wilsonii, Impagidinium rigidaseptatum, Odontochtina operculata, Odontochitina costata, Palynodinium grallator, Raetiaedinium belgicum, Rigaudella appenninica, Trichodinium castanea subsp. castanea, Trigonopyxidia ginella, Trithyrodinium evittii, Trithyrodinum suspectum, Xenascus ceratioides and Xenascus wetzelii. The high diversity of the dinoflagellate cyst taxa made it possible to correlate the Bou Lila section with biostratigraphically well-calibrated upper Campanian sequences from several Tethyan and also Boreal sites, including the type Campanian area and the GSSP for the base of the Maastrichtian in southwestern France and the type Maastrichtian area in Limburg.

The fluctuations in the relative abundances of the selected dinoflagellate cyst groups and other quantitative palynological parameters allow a recognition of three paleoecological zones. They indicate a gradual passage from an inner neritic setting, with high productivity conditions in the most basal part of the section, to a stable outer neritic setting in the upper part of the section.

The palynofacies analyses are in general agreement with the dinoflagellate cyst results, indicating a passage from a proximal depositional environment in the lowermost part of the section to a distal depositional environment in the uppermost part of the section. The dinoflagellate cyst assemblage indicates a subtropical to temperate setting, with the presence of the northern high-latitude cold-water species Palynodinium grallator, suggesting a short cooling episode or also conditions of water stratification during the late Campanian.

作为我们对来自Rif链的上白垩统沉积物的孢粉学研究的一部分，对鞭毛虫囊肿分布和孢粉的本研究是在位于KsarEl-Kébir市（外部Rif）东北的Bou Lila地区进行的。 ，摩洛哥西北部）。该研究的重点是年龄的细化和沉积物沉积过程中盆地内古环境条件的解释。被分析的样品富含类腺形态，基本上由多样且保存完好的二鞭毛囊肿形成，与破骨细胞和稀有的有孔虫试验衬里，孢子，花粉粒和藻类有关。

根据地鞭毛囊肿类群，将Bou Lila部分分配给了Campanian晚期，其第一个外观数据（FAD）或最后一个外观数据（LAD）是Campanian晚期的标记。这些分类群包括：槟榔（Areoligera coronata），槟榔（Areoligera senonensis），黄柏（Cerodiniuum diebelii），查坦吉拉（Chatangiella）。罗布斯塔咖啡，Cribroperidinium天师亚种。天师，Impagidinium rigidaseptatum，Odontochtina operculata，Odontochitina肋脉，Palynodinium grallator，Raetiaedinium belgicum，Rigaudella appenninica，毛癣菌亚种。板栗，Trigonopyxidia ginella，Trithyrodinium evittii，Trithyrodinum suspectum，Xenascus ceratioides和Xenascus wetzelii。鞭毛藻类囊类群的高度多样性使将Bou Lila剖面与来自几个特提斯人和北方地区的生物地层学高度校正的上坎帕尼亚层序相关联成为可能，其中包括坎帕尼亚型地区和法国西南部马斯特里赫特山脉底部的GSSP以及林堡的Maastrichtian类型。

选定的鞭毛藻囊肿组的相对丰度的波动和其他定量的孢粉学参数允许识别三个古生态区。它们表示从该部分最底部的高内部生产环境到内部稳定的环境逐渐过渡到该部分的上部稳定的外部环境。

孢粉分析与鞭毛藻囊肿的结果基本一致，表明从该部分最下部的近端沉积环境到该部分最上部的远端沉积环境。鞭毛藻的囊肿组合表明是亚热带到温带的环境，北部有高纬度冷水物种Palynodinium grallator的存在，这表明在寒武纪后期出现了短暂的降温或水层化的情况。