Based on their facies characteristics and stratal geometries, the carbonate deposits of the Middle Eocene outcropping in the Tamerza area (Western Gafsa Basin) led to the recognition of nine facies that were deposited in shallow marine environment summarized in a carbonate ramp model: homoclinal ramp under an arid climate. The depiction of facies features and the sequential analysis help to determine the depositional environments and establish the linkage between facies evolution, eustasy, climate and tectonics. The vertical evolution of facies shows a regressive trend that records a transition from infratidal to supratidal environments. The stacking pattern revealed several kinds of meter-scale, shallowing-upward cycles. Each cycle starts with relatively open-marine deposits, which are overlain by shallower and more restricted facies (tidal flat progradation). The varied facies, which are described within the Kef Eddour Formation, compose seven depositional sequences, mainly made of carbonates, marls and phosphates. Fauna associations and sedimentary structures imply a shallow subtidal to intertidal, moderately to high-energy platform. Seven sequences are interpreted as depositional sequences showing retrogradational (lowstand systems tract), aggradational (transgressive systems tract) and progradational (highstand systems tract) packages of facies associations. The seven depositional sequences which show a hierarchical organization of many cycles, as described above, suggested that eustatic sea-level oscillations caused by cyclic perturbations of the Earth’s orbit played a fundamental role in determining the formation of hierarchical cyclic rhythmicity.

中文翻译：

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浅海（碳酸盐岩）台地沉积和层序地层演化的控制因素：以加夫萨盆地中始新世沉积为例

根据它们的相特征和地层几何形状，Tamerza 地区（西加夫萨盆地）中始新世露头的碳酸盐沉积物导致识别出沉积在浅海环境中的九种相，总结为碳酸盐斜坡模型：干旱气候。对相特征的描述和序贯分析有助于确定沉积环境，并建立相演化、大气、气候和构造之间的联系。相的垂直演化显示出一种倒退的趋势，记录了从潮下环境到潮上环境的转变。堆积模式揭示了几种米级、变浅-向上的循环。每个周期都从相对开放的海洋矿床开始，它们被更浅和更受限制的相（潮滩前积）所覆盖。在 Kef Eddour 组中描述的各种不同的相组成了七个沉积层序，主要由碳酸盐、泥灰岩和磷酸盐组成。动物群系和沉积结构意味着浅层潮下至潮间带，中等至高能平台。七个层序被解释为沉积层序，显示相组合的逆积（低位系统域）、积积（海进系统域）和进积（高位系统域）包。如上所述，七个沉积序列显示了许多循环的层次结构，