Tournaisian and Visean ammonoid stratigraphy in North Africa

Ammonoids from the Dalle des Iridet of the Mouydir and Ahnet (Central Sahara) and the Formation d'Hassi Sguilma of the Saoura Valley (Late Tournaisian-Early Viséan; Algeria)

“…Stratigraphic scheme of the Early Carboniferous (Mississippian) chronostratigraphy and ammonoid zonation with correlation to the North African ammonoid assemblages (after Korn et al 2004Korn et al , 2007. The position of the fauna from the Iridet Formation and the Hassi Sguilma Formation is highlighted.…”

“…Composition of the ammonoid faunas from the three regions differ to some degree, but resemble each other in the presence of typically latest Tournaisian and earliest Vis an taxa, i.e. the North African Ammonellipsites-Merocanites Assemblage (Korn et al 2007; Fig. 2).…”

Goniatites Zone (middle Mississippian) ammonoids of the Antler Foreland Basin (Nevada, Utah)

“…The Tafilalt, particularly the area around the Gara el Itima, has produced a succession of which four assemblages correlate closely with those observed in North America. The lowest is characterized by Goniatites lazarus, Maxigoniatites saourensis, Maxigoniatites tafilaltensis; Entogonites saharensis, Bollandoceras ergchebbiense, Beyrichoceras elabiodiense, Calygirtyoceras darkaouense, and Prolecanites sp., referred to the local Entogonites-Maxigoniatites Assemblage Zone (Korn et al 2007). In Morocco, the association of Calygirtyoceras darkaouense, which has a widely evolute, almost cadyconic juvenile conch, with Entogonites saharensis closely parallels the Utah association of Calygirtyoceras confusionense with Entogonites borealis.…”

“…-Reports of late Viséan ammonoids from Algeria and Morocco have been made for many years (Delépine 1941), however, only recently has the succession been documented in enough detail that relatively detailed comparisons can be made with Europe and North America (Korn et al 1999(Korn et al , 2005(Korn et al , 2007Klug et al 2006 and references within). The Tafilalt, particularly the area around the Gara el Itima, has produced a succession of which four assemblages correlate closely with those observed in North America.…”

“…Brüning 1923;Schmidt 1925;Nicolaus 1963;Korn 1988Korn , 1990Korn , 1997a, the Ardennes (e.g. de Koninck 1880, Delépine 1940, the South Portuguese Zone (Korn 1997b, Korn & Horn 1997, the Moroccan Meseta (Delé-pine 1941, Korn & Ebbighausen 2008), South Variscan basins such as the Cantabrian Mountains (Kullmann 1961), the Anti-Atlas of Morocco (Korn et al 2005(Korn et al , 2007Klug et al 2006), the South Urals (Bogoslovskaya 1966, Ruzhencev 1966, Novaya Zemlya (Kusina 1987, Kusina & Yatskov 1999, Xinjiang (Liang & Wang 1991), Alaska , and the United States Midcontinent (e.g. Girty 1909Girty , 1911Gordon 1962Gordon , 1965Drahovzal 1972;Drahovzal & Quinn 1972;Saunders et al 1977).…”