To study the Gurpi Formation deposits in Fars area, 230 thin-sections which belong to Well No. 43 have been studied. The Gurpi Formation is 155 m in thickness. Lithology of the Gurpi Formation is mainly composed of thin to medium limestone, argillaceous limestone and shale. Lower boundary of the Gurpi Formation with the Ilam Formation is continuous and its upper boundary with the Pabdeh Formation is disconformity. In biostratigraphy analysis, 14 species belonging to 31 genera of planktonic and benthic foraminifers were identified, and 6 biozones were recognized based on planktonic foraminifera as follow: (1) Globotruncanita elevata Partial range Zone, (2) Globotruncana ventricosa Interval Zone, (3) Radotruncana calcarata Total range Zone, (4) Globotruncanella havanensis Partial range Zone, (5) Globotruncana aegyptiaca Interval range Zone, (6) Gansserina gansseri Interval range Zone. Based on the fossil contents and the identified biozones, the relative age of the Gurpi Formation is Early Campanian–Maastrichtian. Petrographic studies of the Gurpi Formation led to recognition of six facies including five carbonate facies and one shale facies. All facies of the Gurpi Formation belong to the open marine environment, which are deposited in a shelf model. Based on facies analysis and sea level curves, three depositional sequences along with four sequence boundaries due to discontinuities and relative levels of sea level falling were identified. The sequence boundaries at the lower boundary and in the middle part of the Gurpi Formation are type II sequence boundary (SB2). Only the upper boundary of depositional sequence 3 (the boundary between the Gurpi and Pabdeh formations) due to exposure and presence of erosion effects is revealed as a type I sequence boundary (SB1).

中文翻译：

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扎格罗斯盆地（伊朗西南部）法尔斯带 Gurpi 组的沉积环境、层序地层和生物地层

为研究 Fars 地区的 Gurpi 组矿床，研究了 43 号井的 230 个薄片。Gurpi 组的厚度为 155 m。Gurpi组岩性主要由薄至中灰岩、泥质灰岩和页岩组成。Gurpi 组与 Ilam 组的下界是连续的，与 Pabdeh 组的上界是不整合的。在生物地层分析中，共识别出浮游和底栖有孔虫31属14种，根据浮游有孔虫识别出的6个生物区如下：（1）Globotruncanita elevata Partial range Zone，（2）Globotruncana ventricosa Interval Zone，（3） Radotruncana calcarata 总范围区，(4) Globotruncanella havanensis 部分范围区，(5) Globotruncana aegyptiaca 间隔范围区，(6) Gansserina gansseri 区间范围带。根据化石含量和确定的生物带，Gurpi 组的相对年龄为早坎帕阶-马斯特里赫特阶。对 Gurpi 组的岩石学研究导致识别了 6 个相，包括 5 个碳酸盐岩相和 1 个页岩相。Gurpi组的所有相都属于开放海洋环境，沉积在陆架模型中。根据相分析和海平面曲线，确定了由于海平面下降的不连续性和相对水平而导致的三个沉积层序以及四个层序边界。古尔皮组下、中段层序边界为Ⅱ型层序边界（SB2）。