A section of the Lower Cretaceous Taft Formation of Central Iran, belonging to the Yazd Block yields new data about the microfacies, orbitolinid biostratigraphy, and palaeogeographic setting of this poorly known lithostratigraphic unit. The studied section is characterized throughout by the common occurrence of corals, stromatoporoids and small benthic foraminifera (lenticulinids, Neotrocholina) that indicate deposition in an open marine external carbonate platform environment. The orbitolinid assemblage is characterized by Montseciella? arabica (Henson) in the basal part of the section followed by Rectodictyoconus giganteus Schroeder (up to the top), in association with Paleodictyoconus actinostoma Arnaud-Vanneau & Schroeder, Dictyoconus? pachymarginalis Schroeder, and Palorbitolina ultima Cherchi & Schroeder. The observed ranges of some taxa reveal slight modifications of widely used and, therefore, “standard” orbitolinid biozonations. Like any other group of larger benthic foraminifera, orbitolinids display a facies sensitivity (e.g., inner vs. outer platform) that may lead to different local or regional biozonations evidencing the need for plausibility check of the data when transferred to other regions. Moreover, the orbitolinid assemblages observed from different sections of the Taft Formation give evidence for its diachronous base (late Barremian or early Aptian) becoming younger towards presumably exposed land areas.

属于亚兹德地块的伊朗中部下白垩统塔夫脱地层的一部分提供了有关这一鲜为人知的岩石地层单元的微相、轨道生物地层和古地理环境的新数据。研究部分的特点是普遍存在珊瑚、层孔虫和小型底栖有孔虫（豆状毛虫、Neotrocholina），这表明沉积物位于开放的海洋外部碳酸盐台地环境中。 Orbitolinid 组合的特征是Montseciella？阿拉比卡（汉森）在该部分的基部，然后是RECtodictyoconus giganteus Schroeder（到顶部），与Paleodictyoconus actinostoma Arnaud-Vanneau 和 Schroeder、Dictyoconus？pachymarginalis Schroeder 和Palorbitolina ultima Cherchi & Schroeder。一些类群的观察范围揭示了广泛使用的“标准”轨道生物区带的轻微修改。与任何其他较大的底栖有孔虫类群一样，轨道动物表现出相敏感性（例如，内部平台与外部平台），这可能导致不同的局部或区域生物区带，这证明在转移到其他区域时需要对数据进行合理性检查。此外，从塔夫脱地层不同部分观察到的轨道类组合提供了其历时基底（巴列姆晚期或阿普第早期）向可能暴露的陆地区域变得更年轻的证据。