زیست‌چینه‌نگاری نانوفسیل‌های آهکی در بخش بالایی سازند گورپی- بخش ابتدایی سازند ‏پابده (شیل ارغوانی) در یال شمال‌ خاوری تاقدیس کوه گورپی ‏

In this study the upper part of gurpi formation and the lower part of pabdeh formation have been investigated with regard to the calcareous ‎nannofossils. the thinkness of the studied section is about 127 meter and it consists of marls, gray-green shales and purple shales. 50 genus and ‎‎101 species of calcareous nannofossils have been recognised in the studied section. according to the index genus and species in the studied ‎interval, calcareous nannofossil biozones cc25-cc26 have been recognized at the cretaceous sediments and np1-np5 and ntp1-ntp9 biozones ‎have been determined at the paleocene sediments that np1-np4 and ntp1-ntp7a biozones are reported for the first time from the upper part of ‎gurpi formation at the studied section. with regard to these biozones, the age of the upper part of gurpi formation in the studied section is late ‎maastrichtian- late danian (late early paleocene) and the age of pabdeh formation is started from early late paleocene. according to the ‎nannofossil data, the k/pg boundary is continuous and is located at the upper part of gurpi formation. the k/pg boundary is marked by a ‎decrease in abundance of cretaceous species, increase in the abundance of thoracosphaera operculata and the appearance of the new-paleocene ‎taxa. in the danian sediments the cretaceous species are present along with paleocene species continuously and with a good preservation that can ‎be considered as surviving species that may have passed the boundary and are present at the danian sediments.‎