گرفتار در چرخه منحوس فقر

Revision in stratigraphic position of the Cephalopod Bed and the boundary between Devonian and Carboniferous and to introducing 5 Conodont zones in Hoze-Dorah (East Iran)

Conodonts of Cephalopod Bed of Shishtu Formation in its reference section in Howz-e-Dorahf south of Shotori Range, has been studied. The Cephalopod Bed, mainly consists of red oolittic limestone and shale which has a rich macrofossil fauna of cephalopoda, brachiopoda, corals and also a good fauna of conodonts. Conodont study reveals an age of Late Frasnian to Late Famennian for the Cephalopod Bed. A condont zone in the Late Frasnian (gigas) and conodont zones in Famennia/7 (Palmatolepis triangularis, rhomboidea and expansus) also have been introduced. The previous studies indicated Devonian - Carboniferous boundary in a succession of 82 meters thick, which is overlain the Cephalopod Bed (Stocklin et al. 1965 and Stepanov, 1971). In this study the succession which contains Devonian- Carboniferous boundary reduced to 10 meters. In Carboniferous conodont fauna the conodont zone of anchoralis- latus has been introduced.