Streptognathodus (Conodonta) succession at the proposed Carboniferous-Permian boundary stratotype section, Aidaralash Creek, Northern Kazakhstan

Abstract

Streptognathodus Pa elements dominate conodont faunas from the proposed Carboniferous-Permian boundary stratotype at Aidaralash Creek, northern Kazakhstan. The phyletic development of this genus provides the means for subdividing the late Gzhelian to early Sakmarian prodeltaic section (Beds 9-37) into six zones. The preferred Global Stratotype Section and Point (GSSP) for the base of the Permian System is 27 m above the base of Bed 19 at the first occurrence of Streptognathodus isolatus Chernykh, Ritter, and Wardlaw, 1996. This arbitrarily chosen point in the evolutionary continuum of nodose streptognathodids is recognizable in basinal rocks elsewhere in the Ural trough (lower part of Bed 16 at Usolka) as well as the cyclic shelf succession of the American Midcontinent (Glenrock Limestone Member of the Red Eagle Limestone).Eight new species of Streptognathodus occur in the Aidaralash collections: S. bellus n. sp., S. costaeflabellus n. sp., S. flexuosus n. sp., S. glenisteri n. sp., S. longilatus n. sp., S. rectangularis n. sp., S. sigmoidalis n. sp., and S. tenuialveus n. sp. In addition, three morphotypes with limited occurrence (S. sp. A-C) are left in open nomenclature. New collections of topotype material from the nearby Tabantal River section permit clarification of S. barskovi (Kozur).

Discovery of Lower Permian Radiolarian and Conodont Faunas from the Bedded Chert of the Chanthaburi Area Along the Sra Kaeo Suture Zone, Eastern Thailand

“…Asselian to Sakmarian conodonts (S. constrictus) were discovered from the lowermost part of the study section (sample no. SKW11) which have been reported from Southern Ural and South China (Chernykh and Reshetkova, 1986;Chernykh and Ritter, 1997;Wang, 1994). This suggested that the age of the lowermost part of the study section is Asselian (lowermost Permian).…”

“…sp. Among these conodont species, S. constrictus is restricted to the Asselian to Sakmarian of the Southern Urals (Chernykh and Reshetkova, 1986;Chernykh and Ritter, 1997) and South China (Wang, 1994). S. elegantulus was reported from North Thailand by Igo (1974), and is thus Late Carboniferous in age, according to the new definition for the base of the Permian (Jin et al, 1997).…”

Late Pennsylvanian to Wuchiapingian palynostratigraphy of the Baode section in the Ordos Basin, North China

“…The fusulinid assemblages are correlated with the Sphaeroschwagerina Biozone of Asselian-Sakmarian age in South China (Jin and Shang, 2000). Among the conodonts, some specimens assigned to Streptognathodus wabaunsensis have been redetermined as Streptognathodus isolatus (Wang, 2000) which defines the Carboniferous-Permian boundary in the Global Boundary Stratotype (Chernykh and Ritter, 1997). Thus, the Clatratus Biozone is most likely to be of the Asselian-Sakmarian age.…”

The Pennsylvanian–Permian transition in the low-latitude carbonate record and the onset of major Gondwanan glaciation

“…Due to the robust biostratigraphic control (e.g., Thompson, 1954;Ross, 1988, 1995;Ritter, 1995;Chernykh and Ritter, 1997) and minimal tectonic influence (West et al, 1997;Mazzullo, 1999), the U.S. Midcontinent section is ideal for studying PPT sea level change. In many of the other areas described below (except the Russian Platform), the Pennsylvanian-Permian boundary is an easily identifiable unconformity.…”

“…3). The GSSP conodont marker, Streptognathodus isolatus, has been observed in the base of the Bennett Shale (Ritter, 1995;Chernykh and Ritter, 1997) and the Nealian fusulinid fauna (described above) occurs in the Neva Limestone (Thompson, 1954).…”