The Dariyan Formation (of Aptian age) is an important reservoir rock of Cretaceous strata in southwest Iran (the Zagros Zone and the Persian Gulf). Since in carbonate rocks, diagenetic processes directly and primary mineralogy of sediments indirectly affect reservoir characteristics, it is necessary to evaluate these two important parameters in the Dariyan sediments. The most important diagenetic processes were bioturbation, compaction, cementation, and fracturing which have affected the studied sediments. These processes occurred in marine and burial diagenetic environments. Based on the geochemical analysis, these processes have taken place in a closed diagenetic system which led to the preservation of primary characteristics. The deep deposition environment of the sediments and the prevalence of impermeable mud-supported facies are the most important reasons for not affecting meteoric diagenesis. Evaluation of the original mineralogy through petrographic and geochemical information showed that the low-Mg calcite is the most probable option for these sediments. The preserved bioclastic structures and radial fabrics in ooids, presence of skeletal grains with low-Mg calcite mineralogy, and lack of neomorphic features in the lime-mud matrix are the main petrographic evidence for primary LMC mineralogy of these carbonate sediments. Stable isotope and elemental data of the sediments compared with different types of recent and ancient carbonates confirm the proximity of the original mineralogy of the samples to Cretaceous marine limestone with low-Mg calcite mineralogy. This mineralogy is less able for processes such as dolomitization and dissolution than high-Mg calcite and aragonite, respectively. The studied sediments have inherited these characteristics from the paleoenvironmental condition of the Cretaceous Calcite Seas.

Dariyan组（Aptian时代）是伊朗西南部（Zagros区和波斯湾）白垩纪地层的重要储集岩。由于在碳酸盐岩中，成岩过程直接和沉积物的原生矿物学间接影响储层特征，因此有必要对 Dariyan 沉积物中的这两个重要参数进行评估。影响研究沉积物的最重要的成岩过程是生物扰动、压实、胶结和压裂。这些过程发生在海洋和埋藏成岩环境中。根据地球化学分析，这些过程发生在一个封闭的成岩系统中，导致原始特征的保存。沉积物的深层沉积环境和不透水的泥质支撑相盛行是不影响大气成岩作用的最重要原因。通过岩石学和地球化学信息对原始矿物学的评估表明，低镁方解石是这些沉积物最可能的选择。鲕粒中保存的生物碎屑结构和放射状结构、具有低镁方解石矿物学的骨骼颗粒的存在以及石灰泥基质中缺乏新形态特征是这些碳酸盐沉积物的主要 LMC 矿物学的主要岩石学证据。与不同类型的近期和古代碳酸盐相比，沉积物的稳定同位素和元素数据证实了样品的原始矿物学与具有低镁方解石矿物学的白垩纪海相石灰岩接近。与高镁方解石和文石相比，这种矿物学对白云石化和溶解等过程的能力分别较低。所研究的沉积物从白垩纪方解石海的古环境条件中继承了这些特征。