نویسندگان
1 گروه آموزشی زمین شناسی، دانشکده علوم، دانشگاه بیرجند، شهر بیرجند
2 دانشگاه بیرجند
چکیده
کلیدواژهها
عنوان مقاله [English]
نویسندگان [English]
The studied section is located in the 113Km east of Birjand (25Km Asadiyeh City) and east of Pating Village. The mentioned sequence, aged Late Cretaceous, is totally 246m in thickness and mostly consists of thick and medium bedded limestones along rock units. The lower boundary has been limited by basal red conglomerate and the upper boundary has been covered by red-colored sandstone unit. In This research, based on both field and laboratory studies, the main components of carbonate rocks include both skeletal and non-skeletal grains and totally 7 carbonate microfacies have been determined which have been deposited within 3 facies belts including tidal flat, Semi-restricted lagoon and shoal. According to the obtained evidences from the microfacies analysis, the suggested depositional model for the Pating section is a homoclinal ramps type carbonate platform. All of the microfacies are mainly deposited in the inner part of the ramp slope. The obtained geochemical data from carbonate samples analysis indicate a calcitic original mineralogy and dominance of a closed diagenetic system for the studied sequence. Also, according to the geochemical data, a temperate climatic condition could be considered for the formation environment of this sequence which is confirmed by the Late Cretaceous Palaeogeographic global map. The studied limestone samples have been widely affected by different diagenetic processes that the most important of which are micritization, cementation, mechanical and chemical compaction, dissolution, neomorphism, replacement, fracturing and vein-filling cements that have been formed in a variety of marine, meteoric, shallow burial and uplift diagenetic environments.
کلیدواژهها [English]
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