Permo-Triassic Conodonts from Gaduk section, Northeastern Tehran

Abstract:
      The Permo-Triassic sequences are well developed in Gaduk section that is located in North-eastern Tehran. The Permian sediments are derived into 10 rock units. Doroud Formation (Sakmarian- Artinskian?) with thickness of 136.1m rests disconformably on Mobarak's limestone (Visean). Routeh Fm. (Murghabian) rests conformably on Doroud Fm. with the thickness of 412.2 m and is divided into 5 units. It is overlain by 20 m. of bauxite and laterite and then 22.20 m. of volcanic rocks. The Triassic sediments in the form of Elika Formation rests no conformably on Permian sediments with the thickness of 135.4 m, 3 Conodont zones from Permian and 1 conodont zone form Triassic sediments have been distinguished in Gaduk
   section. These zones correspond to international standard conodont zonation (Sweet, 1988)
   1) Neostreptognathus peqoupensis zone Lower Permian
   2) Neostreptognathus ruzhencevi zone (Idahoensis zone)
   3) Sweetognathus whitei zone
   4) Pachycladina zone Triassic
   ? The Amber to Gray Amber color of these Conodonts have shown the CAI=4 which means in the hydrocarbons the end of the Gas production.