The latest Carboniferous-Early Permian Dorud Group of the eastern Alborz (Iran): biostratigraphy and taxonomy of smaller foraminifers

2012 ◽  
Vol 48 (4) ◽  
pp. 385-402 ◽  
Author(s):  
Zohreh Alipour ◽  
Seyyed Mahmood Hosseini-Nezhad ◽  
Daniel Vachard ◽  
Koorosh Rashidi
Keyword(s):  
Early Permian ◽  
Smaller Foraminifers

Biostratigraphy and evolution of Late Carboniferous and Early Permian smaller foraminifers from the Barents Sea (offshore Arctic Norway)

1997 ◽  
Vol 71 (5) ◽  
pp. 758-779 ◽  
Author(s):  
John R. Groves ◽  
Gregory P. Wahlman
Keyword(s):  
Barents Sea ◽  
Early Carboniferous ◽  
High Arctic ◽  
Wall Layer ◽  
Late Carboniferous ◽  
Early Permian ◽  
Smaller Foraminifers ◽  
Phylogenetic Reconstructions ◽  
Iterative Evolution ◽  
Nearly Continuous

Nearly continuous cores from a 500-meter interval of upper Moscovian through post-Artinskian carbonate strata on the Finnmark Platform have yielded rich assemblages of fusulinaceans and smaller foraminifers. The fusulinaceans provide an independent time framework for evaluating stratigraphic occurrences of associated smaller foraminifers. Information derived from this study has been integrated with that from previous investigations to produce a smaller foraminiferal biostratigraphic model for the High Arctic. Kasimovian strata are characterized by occurrences of Nodosinelloides spp., Protonodosaria spp. and Hemigordius schlumbergeri. Overlying lower Gzhelian beds are identified by the appearances of Raphconilia modificata and Amphoratheca iniqua. Tezaquina clivuli and Cribrogenerina gigas first occur in upper Gzhelian strata, and Asselian rocks contain appearances of Geinitzina postcarbonica and Pachyphloia spp. Phylogenetic reconstructions suggest that the Late Carboniferous-Early Permian pseudovidalinids (Archaediscacea) derived from the Pseudoammidiscidae, as did the older group of predominantly Early Carboniferous archaediscaceans. The repeated development of similar morphologies within the two groups of archaediscaceans includes examples of both convergence and iterative evolution. The Protonodosariidae and Syzraniidae most likely evolved from an earlandiid ancestor. The syzraniids gave rise to the Geinitzinidae, which in turn gave rise to the Pachyphloiidae. As in the archaediscaceans, evolution within and among the Earlandiidae, Protonodosariidae, Syzraniidae, Geinitzinidae and Pachyphloiidae includes multiple examples of repeated patterns. Two key phenotypic developments seemingly led to bursts of diversification in different groups throughout late Paleozoic foraminiferal evolution. The acquisition of an outer hyaline or pseudofibrous wall layer was a morphologic breakthrough followed by taxonomic radiation in both groups of archaediscaceans and in the Earlandia-Syzrania lineage. The second major event was the shift from an undivided tubular morphology to uniserial morphology in both the Earlandiidae-Protonodosariidae and Syzraniidae-Geinitzinidae lines. Nodosinelloides pinardae is proposed as a new name for Nodosaria grandis Lipina, 1949 (preoccupied).

A SEED PROFILE FROM THE EARLY PERMIAN RED BEDS OF TEXAS

2018 ◽  
Author(s):  
Cait Conley ◽  
◽  
Rebecca A. Koll ◽  
William DiMichele
Keyword(s):  
Early Permian ◽  
Red Beds
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