Records of the conodont
Icriodus woschmidti allowed these beds to be dated more precisely as the Lochkovian (Early Devonian) (Zhivkovich & Chekhovich 1985).
fauna suggest that the PT boundary coincides with the disconformity at the Chhidru-Mianwali formations but the palynological assemblages from the upper-most Chhidru Formation have affinities with Permian as well as Griesbachian (basal Early Triassic).
The miospores belong to the Emphanisporites annulatus--Camarozonotriletes sextantii Assemblage Zone (Richardson and McGregor 1986), which corresponds approximately to the Polygnathus dehiscens to Polygnathus serotinus conodont
zones of early Emsian to early late Emsian age (Blieck and Cloutier 2000).
faunas are dominated by Idiognathodus and Adetognathus.
There were several metres of thin to medium-bedded Claraia vermicular limestone inter-bedded with coloured shale above the key bed; this belonged to the Early Triassic, based on a study of conodont
Preliminary report on conodont
and Sm-Nd isotope data from Upper Ordovician Red River strata (Herald and Yeoman formations) in the Williston Basin, Berkley et al Midale 12-2-7-11W2, southeastern Saskatchewan.
To date, this record has been exploited successfully but solely for its biostratigraphic significance; the evolutionary significance of lineages, reconstructed through biostratigraphy, has not been realised because the tooth function of conodont
elements has been determined only very recently.
Other chapters offer a detailed analysis of the marine platform-deltaic system of Argentina's San Rafael Block and the upper Devonian miospore and conodont
zone correlation in western Europe.
Although unconformities separate these carbonate units (the Walberg Unconformity separates the Columbus Limestone from the underlying Salina undifferentiated and the australis conodont
zone is unrecorded in Central Ohio [Sparling 1983, 1985] between the Columbus Limestone and the overlying Delaware Limestone), the Silurian and Devonian carbonates act as a single hydrologic unit, confined below by Ordovician shale-rich units.
In terms of North Atlantic conodont
succession the stage seems to correspond to the uppermost part of the Pygodus anserinus Zone, the Prioniodus variabilis (most part of the stage) and to the lowermost Prioniodus gerdae subzones of the Amorphognathus tvaerensis Zone (Mannil 1986)".
from the condensed interval represent several standard Chesterian conodont
zones and, by comparison with conodonts
from the rest of the section, sugge st a tentative correlation of the Bangor to no more than the Haney Limestone through the lower part of the Menard Formation in the standard North American Illinois Basin section.
Less than half of the 42 samples collected for conodont
studies were productive, and only 163 elements were obtained.