نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه زمین شناسی، دانشگاه شهید باهنر کرمان، کرمان، ایران
2 گروه زمین شناسی، دانشکده علوم، دانشگاه فردوسی مشهد ، مشهد، ایران
3 دانشیار گروه زمین شناسی، دانشکده علوم پایه، دانشگاه فردوسی مشهد
4 گروه زمین شناسی، دانشکده علوم، دانشگاه فردوسی مشهد، مشهد ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Abstract
In the present study, biostratigraphy and paleoecology of calcareous nannofossils from the upper parts of Neyzar Formation and the basal parts of the Kalat Formation in the east of the Kopet-Dagh basin, Tang-e-Neyzar section, are investigated. In the studied section, the lithology of these formations includes calcareous shales and gray to greenish marls. A paleosol horizon is present in the upper parts of the Neyzar Formation in the Tang-e-Neyzar section. Calcareous nannofossil studies lead to the identification of 27 genera and 56 species and two sub-species. Based on the identified genus and species, which is based on Burnett zonation UC15eTP sub-zone and the upper parts of CC22 Sissingh zonation, the age of studied section is the “early Late Campanian”. Paleoecological study of calcareous nannofossils shows the presence of relatively cool water genus like Micula decussata، Prediscosphaera spp.،Eiffellithus spp. and Arkhangelskiella cymbiformis. Meanwhile, the presence of Prediscosphaera spp.، Eiffellithus spp. and Arkhangelskiella indicate Oligotrophic waters. Due to the presence of the cool water genus and species, it is interpreted that the temperature was decreasing (cool greenhouse) during "early late Campanian” time in the studied area, similar to other parts of the world.
کلیدواژهها [English]