Lithostratigraphic and Biostratigraphic studies of Neyzar Formation in Jalil- Abad section (northwest of Mashhad, Iran)

Abstract

Kopet_ Dagh mountains with NW- SE trend is located in north and northeast of Iran. One of the most formations of Kopet- Dagh basin is Neyzar Formation with Upper Cretaceous age. Studied section located in southern flank of Kalat-e-Naderi syncline, 141 km northwest of Mashhad and adjacent of Kalat-e-Naderi city. <br><br>The thickness of Neyzar Formation 555.5 meter was measured. Based on morphological and petrographic characteristics divided to 8 units.<br><br>The lower contact of Neyzar Formation with Abtalkh Formation is conformable and the upper contact this formation with Kalat Formation is Disconformable (as a paleosol). At the first time, on the base of Micropaleontological studies, 33 species belonging to 26 genera of Planktonic and Benthonic foraminifer have been reported. <br><br>Based on fossils identified especially, Siderolites calcitrapoides, Abathomphalus mayaroensis, Orbitoides apiculata, Orbitoides media, Maaastrichtian especially Late Maastrichtian age for Neyzar Formation have been determined. According to recognized facies, the Neyzar Formation in a Carbonate platform (Ramp type with Bar Islands) has been deposited