S. M. Hamidzadeh; A. Babazadeh; B. Asgari – Pirbaluti; A. Solgi
Abstract
The Asmari Formation was measured and sampeled in Ghar-e Agha Seyyed at Farsan area in order to determine sedimentary environment based on facies analysis. In the study area, the Asmari Formation has a thickness of 183 m and conformably underlained the Pabdeh Formation. Based on microfacies studies, ...
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The Asmari Formation was measured and sampeled in Ghar-e Agha Seyyed at Farsan area in order to determine sedimentary environment based on facies analysis. In the study area, the Asmari Formation has a thickness of 183 m and conformably underlained the Pabdeh Formation. Based on microfacies studies, 8 microfacies were recognized such as:1) Porcelanouse foraminifera – bioclastic – red algal wackestone / packstone, 2) Rotalia grainstone, 3) Bioclastic –red algal grainstone, 4) Red algal – coral boundstone, 5) Red algal wackestone (Floatstone), 6) Red algal –large hyaline foraminifera – intraclast packstone, 7) Red algal – bioclastic - large hyaline foraminifera wackestone / packstone, 8) Large hyaline foraminifera packstone. These microfacies represent three facies belts including Inner ramp, Middle ramp and Outer ramp. On the other hand, based on the presence of benthic foraminifera, the age of the Asmari Formation is related to Oligocene (Rupelian – Chatian).
S.A Babazadeh; M Rahmati
Abstract
Carbonate sedimentary rocks equivalent to Asmari Formation containing thick and thin bedded and massive limestones with a thickness of 160m studied in Posht-Darband, Hamadan. The base of the sedimentary sequence begun with a transgressive conglomeratic horizon. This horizon is composed of rock ...
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Carbonate sedimentary rocks equivalent to Asmari Formation containing thick and thin bedded and massive limestones with a thickness of 160m studied in Posht-Darband, Hamadan. The base of the sedimentary sequence begun with a transgressive conglomeratic horizon. This horizon is composed of rock fragments such as cherts, schists and fossiliferouslimestones which are derived from adjacent old rock units. The lower contact of conglomerate horizon overlains the metamorphic rocks and the upper contact is covered by alluvium. Based on the study of thin sections from Asmari Formation, two main facies belts containing inner and middle ramps are recognized. The inner ramp composes restricted lagoon, rotalid shoal, protected lagoon and patch reef whiles the middle ramp contains proximal, middle and distal parts respectively. Based on microscopic studies, eight microfacies are presented which are consist of; 1-Large perforate foraminifera-bioclastwackestone, 2-Perforate foraminifera-red algal-bioclastpackstone/grainstone, 3-Coralgal-bioclast packstone/grainstone, 4-Coral-redalgal packstone/grainstone, 5-Imperforate foraminifera-pelloid-bioclastpackstone, 6-Rotalia grainstone, 7-Perforate-imperforate foraminifera packstone/grainstone and 8-Miliolid-bioclast-intraclast packstone. They are deposited in seven sedimentary environments. According to microfacies, this formation is distributed from tidal flat to middle ramp. The Chatian (Late Oligocene) age is attributed to these carbonate rocks based on benthic foraminifera recorded.
S.A Babazadeh; M Ghavidel-Syooki; H Ghasabi
Abstract
The Asmari Formation is well-exposed at Kuh-e-Mish, locating at Gorg-Darreh area (The Zagros fold-thrust belt). In this area, the true thickness of Asmari Formation is 480m. This formation was studied for its microfacies analysis in Gorg-Darreh area (kuh-e-Mish). In this study, seven microfacies was ...
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The Asmari Formation is well-exposed at Kuh-e-Mish, locating at Gorg-Darreh area (The Zagros fold-thrust belt). In this area, the true thickness of Asmari Formation is 480m. This formation was studied for its microfacies analysis in Gorg-Darreh area (kuh-e-Mish). In this study, seven microfacies was recognized within this formation. These microfacies belong to the tidal flat, restricted lagoon, protected lagoon, patch reef, foreslope, basin sub-environments. A carbonate ramp is suggested for depositional environments of the Asmari Formation. Likewise, distributions of foraminifers of this formation were studied in order to determine the age relationships of the Asmari Formation. In this study, 45 species belonging to 41 genera were identified. In general, three assemblage biozones were recognized in this formation, consisting of Lepidocyclina – Operculina - Ditrupa Assemblage Zone, Peneroplis evolutus - Austrotrillina howchini Assemblage Zone and Borelis melo curdica – Meandropsina iranica Assemblage Zone. Therefore, based on these assemblage biozones, the Asmari Formation is assigned to late Oligocene (Chattian) – early Miocene (Aquitanian- Burdigalian).
S Azadbakht; M.R Majidifard; S.A Babazadeh
Abstract
In this study, the Surgah formation is identified and introduced for the first time in the east of Khoram-Abad. This formation in the east of Khoram-Abad consists of up to 260 meters light grey, thin to thick –bedded limestone with intercalation of shaly-limestone and a Turonian to Santonian age. ...
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In this study, the Surgah formation is identified and introduced for the first time in the east of Khoram-Abad. This formation in the east of Khoram-Abad consists of up to 260 meters light grey, thin to thick –bedded limestone with intercalation of shaly-limestone and a Turonian to Santonian age. In this section, the Surgah formation has continuous and conformable contacts with the lower Sarvak formation and the upper Ilam formation. In this study, 13 genera, 33 species and 3 biozones of the planktonic foraminifera have been recognized: Biozon I, Helvetoglobotruncanahelvetica-Clavihedbergella –Hedbergella Assemblage Zone indicating Turonian age, Biozon II, Marginotruncana sigali- Marginotruncana schneegansi Assemblage Zone indicating Coniacian age, and Biozone III, Globotruncana ventircosa -Dicarinella concavata Assemblage Zone showing Santonian age.
