Abstract This study presents a detailed facies analysis of an 800 m-thick stratigraphic succession in the basinal turbidites of the Macigno Sandstones Formation (MSF) recording the first foredeep in the northern Apennines (Italy). This stratigraphic succession shows an evident stacking pattern that, besides the basal part (200 m thick) dominated by fine grained and thin beds, is characterized by seven magnificently exposed sandstone lobes (from 90 to 19 m thick) separated by well-developed fine-grained interlobe deposits. Thanks to the detailed facies analysis, not only a well-defined architectural hierarchy has been identified, but a facies schemes has also been proposed, whereby cyclic recurring of three facies associations has in turn been identified. Each facies association records a well-determined evolutionary stage of lobe development, where an early depositional stage of the lobe building phase is followed by a flow impact and bypass stage recording flow decelerations and hydraulic jumps induced by the morphology created by the underlying depositional lobe. The latter phase promotes a switching and channel feeder avulsion that heralds the third phase of abandonment with the deposition of fine-grained interlobes. The facies stacking pattern and the evolutionary model of the MSF - also supported by other similar field and experimental works - are intended as a contribution to the understanding of intrinsic autogenic mechanisms at the basis of sand-rich depositional lobe development.

中文翻译：

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Macigno 砂岩组（Chattian-Aquitanian，北亚平宁山脉，意大利）浊积裂片的循环堆积模式、结构和相

摘要 本研究对马西尼奥砂岩组 (MSF) 盆地浊积岩中 800 米厚的地层序列进行了详细的相分析，记录了亚平宁山脉北部（意大利）的第一个前渊。该地层序列显示出明显的叠置格局，除以细粒薄层为主的基底部分（200 m 厚）外，其特征还包括七个出露华丽的砂岩裂片（厚 90 至 19 m），被发育良好的细粒状叶间沉积物。由于详细的相分析，不仅确定了定义明确的建筑层次结构，而且还提出了相方案，从而依次确定了三个相关联的循环重复。每个相协会记录了一个明确的叶发育进化阶段，其中，叶瓣构建阶段的早期沉积阶段之后是流动冲击和旁路阶段，记录了由底层沉积叶瓣产生的形态引起的流动减速和水跃。后一阶段促进转换和通道馈线撕脱，预示着第三阶段的废弃，细粒间叶的沉积。MSF 的相堆积模式和演化模型——也得到其他类似领域和实验工作的支持——旨在作为对富含砂沉积叶发育基础的内在自生机制的理解的贡献。