the kopet-dagh basin extended in the north and north east of iran and consists of marine strata from middle jurassic to paleogene time. abtalkh formation is one of the thickest lithostratigraphic units of cretaceous in the kopet-dagh basin and is composed of light gray, green to bluish marl and silty marl. the abtalkh formation conformably overlies the marls and chalky limestones of the abderaz...

Rare calcareous nannofossils from the Cape Roberts Project drillhole CRP-2A indicate that this area was episodically invaded by marginal oceanic surface waters during the late and late early Oligocene. These depauperate assemblages lack most of the biostratigraphic index fossils for the Oligocene, but do provide two datums that aid in constraining the age of the section: the last appearance dat...

Ocean Drilling Program holes 744A and 748B represent key sections for calibration of Southern Ocean Eocene^ Oligocene biostratigraphic zonations. Sites 744 and 748 were above the carbonate compensation depth throughout this time interval and contain good planktonic foraminiferal, calcareous nannofossil, and diatom biostratigraphic records. In particular, the Southern Ocean diatom biostratigraph...

A succession of Late Campanian- Early Maastrichtian is analyzed from Gurpi Formation with regard to the calcareous nannofossils. Correlation Matrix was applied for the first time to the entire nannofossil assemblage to reconstruct environmental conditions. A detailed quantitative calcareous nannofossil analyses is performed on samples in order to further investigate the climate events, and inte...

Volcanic ash was recovered from lower Aptian to Albian deposits from DSDP Sites 463, 465, and 466; pelagic clay of the upper Pleistocene to Upper Cretaceous was recovered mainly from Site 464, with minor amounts at Sites 465 and 466 (Figs. 1 and 2). We present X-ray-mineralogy data on pelagic clay and altered volcanic ash recovered from the four Leg 62 sites (Table 1; Fig. 1). In addition, two ...

This study presents calcareous nannofossils biostratigraphy of the Campanian‒Danian interval at the Gurpi Formation in the southwest of Ilam Province, in the Zagros Basin. The studied sequence of the Gurpi Formation mainly consists of marly shale and limestones. The thickness of Gurpi Formation was measured as approximately 230 m. Forty-five species belonging to twenty-eight genera were recorde...

Well preserved nannofossil assemblages in upper Albian and lower Cenomanian hemipelagic sections from Ocean Drilling Program (ODP) Leg 171B preserve a record of the early history and adaptive radiation of the genus Eiffellithus. Seven distinct taxa are recognized and differentiated, with one previously named taxon (E. monechiae) emended and four new species described: E. praestigium, E. vonsali...

this study presents the nannostratigraphy and nannofossil events in the lower boundary of kalat formation in the east and west of the kopeh- dagh basin. the kalat formation comprises of coarse grained detritus limestone with subordinate sandstone intercalations. in the current study, six sections have been chosen in the east and west of the basin which are as follow: dobaradar section, kalat se...