The analysis of successive conodont assemblages from Carboniferous-Permian boundary sediments of the Aidarlash and Usolka sections revealed that the boundary approaching that in the ammonoid standard is in the transition ...
Leven E.Ja.; Boiko M.S.; Reimers A.N.; Leonova T.B.; Bogoslovskaya M.F.(2002)
One of the most complete sections of Permian deposits in the southern Urals is described. It spans the middle Asselian-Artinskian interval and yields fusulinids, ammonoids, and conodonts. The upper half of the Uskalyk ...
The evolution history of fusulinids, brachiopods, ammonoids, and conodonts shows that while advancing across the Sakmarian-Artinskian boundary, all these faunal groups suffered a crisis that was followed by a peak of their ...