نوع مقاله : علمی -پژوهشی
نویسنده
دانشگاه بین المللی امام خمینی (ره)، قزوین
چکیده
در این تحقیق، زیست چینه نگاری سازند پابده در شمال ایلام مورد مطالعه قرار گرفته است. مطالعه نانو فسیلهای آهکی منجر به تشخیص 77 گونه و 29 جنس گردید. مطابق با اولین حضور گونههای شاخص و گسترش تجمعات فسیلی، بایوزونهای Heliolithus kleinpellii Zone (NP6), Discoaster mohleri Zone (NP7), Heliolithus riedelii Zone (NP8), Discoaster multiradiatus Zone (NP9), Tribrachiatus contortus Zone (NP10), Discoaster binodosus Zone (NP11), Tribrachiatus orthostylus Zone (NP12), Discoaster lodoensis Zone (NP13), Discoaster sublodoensis Zone (NP14), Nannotetrina fulgens Zone (NP15), Discoaster tani nodifer Zone (NP16), Discoaster saipanensis Zone (NP17), Chiasmolithus oamaruensis Zone (NP18), Isthmolithus recurvus Zone (NP19), Sphenolithus pseudoradians Zone (NP20), Ericsonia subdisticha Zone (NP21), Helicosphaera reticulata Zone (NP22), Sphenolithus predistentus Zone (NP23), Sphenolithus distentus Zone (NP24) که با زون بندی مارتینی (1971) و بیوزونهای (CP5- CP19) از زون بندی آکادا و بوکری (1980) مطابقت دارد در برش رنو شناسایی شد. در نتیجه این مطالعه و بر اساس زونهای مشخص شده سن سازند پابده در شمال ایلام از پالئوسن پسین (Thanetian) تا الیگوسن میانی پیشنهاد میشود. AbstractIn this research, biostratigraphy of the Pabdeh Formation in North Ilam was studied. The study of calcareous nannofossil led to the recognition of 77 species and 29 genera. According to the first occurrence of index species and distribution fossil assemblages, zones (Heliolithus kleinpellii Zone, Discoaster mohleri Zone, Heliolithus riedelii Zone, Discoaster multiradiatus Zone, Tribrachiatus contortus Zone, Discoaster binodosus Zone, Tribrachiatus orthostylus Zone, Discoaster lodoensis Zone, Discoaster sublodoensis Zone, Nannotetrina fulgens Zone, Discoaster tani nodifer Zone, Discoaster saipanensis Zone, Chiasmolithus oamaruensis Zone, Isthmolithus recurvus Zone, Sphenolithus pseudoradians Zone, Ericsonia subdisticha Zone, Helicosphaera reticulata Zone, Sphenolithus predistentus Zone, Sphenolithus distentus Zone) of Martini (1971) equivalent to bio zones (CP5- CP19) of Okada and Bukry (1980) at Reno section were identified. As a result of this study and based on the obtained bio zones, age of the Pabdeh Formation in North of Ilam, is Late Paleocene (Thanetian) to Middle Oligocene. Keywords: Oligocene, Ilam, Pabdeh, Paleocene, Calcareous nannofossil.
کلیدواژهها
عنوان مقاله [English]
ش
چکیده [English]
In this research, biostratigraphy of the Pabdeh Formation in North Ilam was studied. The study of calcareous nannofossil led to recognition of 77 species and 28 genera. According to the first occurrence of index species and distribution fossil assemblages, zones (Heliolithus kleinpellii Zone, Discoaster mohleri Zone, Heliolithus riedelii Zone, Discoaster multiradiatus Zone, Tribrachiatus contortus Zone, Discoaster binodosus Zone, Tribrachiatus orthostylus Zone, Discoaster lodoensis Zone, Discoaster sublodoensis Zone, Nannotetrina fulgens Zone, Discoaster tani nodifer Zone, Discoaster saipanensis Zone, Chiasmolithus oamaruensis Zone, Isthmolithus recurvus Zone, Sphenolithus pseudoradians Zone, Ericsonia subdisticha Zone, Helicosphaera reticulata Zone, Sphenolithus predistentus Zone, Sphenolithus distentus Zone) of Martini (1971) equivalent to bio zones (CP5- CP19) of Okada and Bukry (1980) at Reno section were identified. As a result of this study and based on the obtained bio zones, age of the Pabdeh Formation in North of Ilam, is Late Paleocene (Thanetian) to Early Oligocene (Rupelian).
کلیدواژهها [English]
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Ilam- Oligocene-Pabdeh-Paleocene- calcareous nannofossil