CONODONTS OF THE LOWERMOST TRIASSIC OF SPITI, AND NEW ZONATION BASED ON NEOGONDOLELLA SUCCESSIONS ...

• Main Authors: J. ORCHARD, MICHAEL, KRYSTYN, LEOPOLD
• Format: Article in Journal/Newspaper
• Language: English
• Published: Università degli Studi di Milano 1998
• Subjects: Arctic
• Online Access: https://dx.doi.org/10.13130/2039-4942/5339; http://riviste.unimi.it/index.php/RIPS/article/view/5339

Conodonts from the lowermost Triassic Otoceras woodwardi beds and adjacent strata of Spiti are described and compared with Permian-Triassic (P-T) boundary bed faunas from elsewhere. A new pelagic zonation based on Neogondolella is introduced: the interval characterized by N. carinata-N. taylorae is subdivided into three parts based on successive first appearances of N. meishanensis, N. krystyni Orchard n. sp. and N. discreta Orchard and Krystyn n. sp., the nominal species of three successive zones. The development of these Griesbachian species involves a progressive morphological change in the configuration of the axial part (blade-carina-cusp) of the pectiniform elements. The pelagic conodont zonation is intercalibrated with the parallel zonation based on species of Hindeodus and Isarcicella, and with ammonoid faunas from Spiti, other Himalayan localities, and the Arctic. The meishanensis Zone embraces the parvus Zone and part of the overlying staeschei Zone. Strata containing O. woodwardi in Spiti carry ... : Rivista italiana di Paleontologia e Stratigrafia, Vol 104, No 3 ...