نویسندگان
1 گروه زمین شناسی، واحد خرم آباد، دانشگاه آزاد اسلامی، خرم آباد، ایران.
2 دانشجوی دکترا رسوب‌شناسی و سنگ‌رسوبی، دانشگاه بوعلی‌سینا، همدان، ایران، کارشناس آزمایشگاه مرکزی دانشگاه لرستان، خرم‌آباد، ایران
چکیده
کلیدواژه‌ها
عنوان مقاله [English]
نویسندگان [English]
In this study, Shahbazan Formation has been studied from the perspective of diagenetic processes and paragenetic sequences. This formation extends to the middle to late Eocene age in a large area of Lorestan sedimentary basin. In this area, a 62-meter-thick surface section has been selected in 10 km northwest of Poldokhtar city. Shahbazan Formation in the study area is located on the Kashkan detrital Formation and is covered by carbonates of Asmari Formation as a continuous discontinuity. Petrographic studies have been performed on thin sections and SEM studies have been performed on 10 samples of dolomites. Petrographic studies led to the identification of several diagenetic processes such as micritization, neomorphism, cementation, compaction, dissolution and replacement, which finally determined the diagenetic model. Based on the petrographic evidence, the paragenetic sequence of the Shahbazan Formation deposits in this section has been interpreted in four marine environments, freshwater, burial and uplift, and during three stages of diagenesis, namely primary diagenesis (Eogenetic), middle diagenesis (Mesogenetic) and late diagenesis (Telogenetic) has been determined. The most important diagenetic process in the studied section is dolomitization, which is formed both primary and secondary. Primary dolomites have low amounts of Fe and high amounts of Sr and Na, while secondary dolomites have high concentrations of Fe and lower amounts of Sr than primary dolomites, indicating a diagenetic burial environment. Shallow to medium for secondary dolomites.
کلیدواژه‌ها [English]
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