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Somerville I.D.,University College Dublin | Rodriguez S.,Institute Geociencias CSIC | Said I.,Institute Geociencias CSIC | Cozar P.,Complutense University of Madrid
Geologica Belgica | Year: 2012

Analysis of Mississippian coral assemblages from the Khenifra region of Central Morocco has demonstrated the presence of a rich and diverse coral fauna. Rugose coral assemblages from the Tabainout mud-mound complex comprise abundant colonial and solitary taxa, particularly in the basal bedded limestones, as well as the upper bedded flank and coquina capping beds. The massive core facies with stromatactoid cavities in contrast has rare solitary corals. The overlying shales, marls and limestone bands which buried the mud-mound are dominated by small non-dissepimented solitary rugosans. The age of the Tabainout mound based on foraminifers is established as upper Viséan (late Asbian-late Brigantian). The coral assemblage strengthens correlations with the Adarouch area in the northern part of the Azrou-Khenifra Basin where similar mud mounds occur. These assemblages also show similarity with coeval coral faunas from the Jerada mud-mounds (buildups) of NE Morocco and together represent part of the same palaeobiogeographic province (Western European Coral Province). Source

Cozar P.,Institute Geociencias CSIC | Somerville I.D.,University College Dublin
Geological Journal | Year: 2015

A detailed study of foraminiferal assemblages recorded in limestones from northern England in the Stainmore Trough and Alston Block permits their assignment to different European substages than in previous studies. Comparisons with foraminiferal assemblages, mostly from Russia, allow the biozonations to be correlated with the Viséan, Serpukhovian and Bashkirian international stages, as well as with the Russian (and Ukrainian) substages for the Serpukhovian (Tarussian, Steshevian, Protvian and Zapaltyubian). The Scar Limestone and Five Yard Limestone Members are assigned to the Tarussian and, thus, represent the lowermost part of the formal Serpukhovian Stage. This new correlation coincides closely with the first occurrence of the conodont Lochriea ziegleri from levels equivalent to the Single Post Limestone that could potentially form the revised base for the Serpukhovian. The Three Yard Limestone Member is correlated with the base of the Steshevian substage which also includes the Four Fathom Limestone Member, Great Limestone Member and Little Limestone. The base of the Protvian is considered to lie within the Crag Limestone, whereas the Rookhope Shell Band contains foraminiferal assemblages more typical of the Zapaltyubian in the Ukraine and Chernyshevkian in the Urals. Assemblages of the Upper Fell Top Limestone and Grindstone/Botany Limestones contain foraminiferal species that have been used for the recognition of the Bashkirian elsewhere. There is no other fossil group which allows the calibration of those foraminiferal assemblages, because ammonoids are virtually absent in the shallow-water cyclothemic successions and conodonts have not been studied in detail in this region. The Mid-Carboniferous boundary and the Voznessenian substage might be reasonably located below the Upper Fell Top Limestone. © 2015 John Wiley & Sons, Ltd. Source

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