Abstract Integrated methods have been applied for the high resolution sequence stratigraphic analysis of a mixed petroliferous carbonate-siliciclastic succession of the Asmari Formation (Oligocene-Miocene) in the Zagros Basin. Detailed sedimentological (core description) and petrographical (one thousand one hundred fifty thin sections) analysis led to identification of more than 38 carbonate and siliciclastic facies (basin wide) that have been deposited in four types of depositional environments, including inner ramp, mid ramp, outer ramp and basin, in homoclinal ramp type carbonate platform. An integrated multidisciplinary approach including core descriptions, petrography, biostratigraphy, gamma-ray spectrometry (e.g., uranium (U), thorium (Th) and Potassium (K)), oxygen and carbon isotopes (Chemo-stratigraphy) and trace element analysis have been used for stratigraphic interpretations of this succession. Based on petrography, biostratigraphy, lateral and vertical facies changes, and GR log, 6 third-order cycles distinguished, whose boundaries correspond to distinct δ13C and δ18O negative peaks. Trace elements (Fe and Mn) contents along with oxygen and carbon isotopes variations are compared with distribution of sedimentary facies and depositional sequences to investigate and correlate stratigraphic boundaries, which are determined by sequence stratigraphy (GR log and facies analysis) and stable isotope stratigraphy (Chemo-stratigraphic) in shallow marine carbonate platform of the Asmari. Negative isotope and elemental peaks coinciding with the sequence boundaries while the positive isotope and elemental peaks are correlated with maximum flooding surfaces. Changes in the frequency of uranium (U), thorium (Th), and Potassium (K) has been used to investigate the stratal surface and sequence boundaries as well as oxidation and reduction states. Fourth-order sequences that formed during the formation of the third-order sequence could be distinguished and separated by uranium log.

中文翻译：

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稳定同位素、微量元素和能谱伽马射线测井在解析碳酸盐岩-硅碎屑岩混合储层高频地层序列中的应用

摘要 综合方法已应用于扎格罗斯盆地阿斯马里组（渐新世-中新世）混合含油气碳酸盐岩-硅质碎屑岩层序的高分辨率层序地层分析。详细的沉积学（岩心描述）和岩相学（一千一百五十个薄片）分析导致识别出超过 38 个碳酸盐和硅质碎屑相（盆地范围内）沉积在四种类型的沉积环境中，包括内斜坡、中斜坡，外斜坡和盆地，在同斜斜坡型碳酸盐台地。一种综合的多学科方法，包括核心描述、岩石学、生物地层学、伽马射线光谱学（例如，铀 (U)、钍 (Th) 和钾 (K)），氧和碳同位素（化学地层学）和微量元素分析已被用于这一层序的地层学解释。根据岩石学、生物地层学、横向和垂直相变化以及GR测井，区分出6个三级旋回，其边界对应于不同的δ13C和δ18O负峰。将微量元素（Fe 和 Mn）含量以及氧和碳同位素变化与沉积相和沉积序列的分布进行比较，以调查和关联地层边界，这些边界由层序地层学（GR 测井和相分析）和稳定同位素地层学（化学地层）在阿斯马里浅海碳酸盐台地。负同位素和元素峰与层序边界重合，而正同位素和元素峰与最大洪水面相关。铀 (U)、钍 (Th) 和钾 (K) 频率的变化已被用于研究地层表面和层序边界以及氧化和还原状态。在三阶层序形成过程中形成的四阶层序可以通过铀测井来区分和分离。