Between Lagos and Albufeira, the Algarve coast of southern Portugal is marked by outcrops of the lower Miocene Lagos-Portimão Formation (LPF) consisting of yellow sandstone and coarse skeletal-rhodolithic limestone. This contribution focuses on the rhodoliths, their paleoecology, taphonomy, and biological composition, in the Lagos Biocalcarenite, the lower member of the LPF. Special attention is paid to the unusual occurrence of numerous rhodoliths nucleated around articulated bivalve shells, as well as to the nature of their biological interactions and taphonomic features. The calcareous algae of the rhodoliths (Phymatolithon calcareum and Spongites sp.) are commonly interlayered with thin bands of bryozoans and serpulids. Thick beds of non-nucleated spheroidal rhodoliths first appear at approximately 5–6 m above the base of the LPF as a result of a storm event that shifted rhodoliths in a shoreward direction. The bioeroded surface at the top of the Cretaceous Porto de Mós Formation, at the base of the overlying LPF succession, is a wave-cut platform representing the Miocene transgressive surface.

中文翻译：

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下中新世双壳类和大类生物组合的古环境和埋藏学：Lagos Biocalcarenite（Lagos-Portimão Formation，葡萄牙南部）

在拉各斯和阿尔布费拉之间，葡萄牙南部的阿尔加维海岸以下中新世拉各斯-波尔蒂芒组 (LPF) 的露头为标志，该组由黄色砂岩和粗骨架红石灰岩组成。这一贡献侧重于 LPF 下部成员拉各斯生物钙质岩中的红石、它们的古生态学、埋藏学和生物组成。特别注意在铰接式双壳贝壳周围成核的大量红石的不寻常发生，以及它们的生物相互作用和埋藏学特征的性质。红石藻（Phymatolithon calcareum 和 Spongites sp.）的钙质藻类通常夹杂着苔藓虫和蛇虫的薄带。由于风暴事件使红石向岸边移动，因此厚厚的无核球状红石层首先出现在 LPF 底部上方约 5-6 m 处。位于上覆 LPF 层序底部的白垩纪 Porto de Mós 组顶部的生物侵蚀表面是一个代表中新世海侵表面的波浪切割平台。