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The Upper Campanian - lower Maastrichtian cephalopod fauna of Botellos, Nuevo León: a key to understand faunal turnover across the Campanian-Maastrichtian boundary in NE Mexico

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Ifrim C. , Lara de la Cerda J. E. , Peña Ponce V. H. , Stinnesbeck W.

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tom Vol. 67, no. 1

145--162

EN

A new cephalopod collection from the Campanian-Maastrichtian boundary interval of NE Mexico, consisting of 1076 individuals assigned to 29 species and 22 genera is presented. This collection is a mix of ammonoids, one coleoid and one nautilid, which originate from at least three ammonoid biozones: The upper Campanian Exiteloceras jenneyi and Nostoceras (Nostoceras) hyatti zones, and the lower Maastrichtian Pachydiscus (Pachydiscus) neubergicus Zone. The age of the collection is thus middle late Campanian to late early Maastrichtian, and it closes a stratigraphic gap between faunas described formerly from this region. The specimens are nuclei collected from the desert pavement. The abundance of specimens allows for a comparison to other Campanian-Maastrichtian ammonoid records from Mexico, North America and Europe.

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Tectono-sedimentologic and lithostratigraphic control in Aures Region: Case study Djebel Metlili, Batna, Algeria

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Touahri A. , Sahraoui S. , Benmansour S. , Hadjkouider M.

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tom no. 2

111--124

EN

This research delves into the geological features of the western section of the Aures Basin, with a primary focus on Djebel Metlili. The geological characteristics span Mesozoic and Tertiary deposits, ranging from the Triassic to the Quaternary epochs. Notably, the higher Cretaceous period stands out for its substantial carbonate-rich sequence. The research relied on geological maps, field observations, core samples, and laboratory analyses, including lithostratigraphic examinations (cross-section) and thin section. Structural features show that is formed by large regular folds of ENE-WSW or E-W direction. Anticlines and synclines are often affected by transverse accidents at the axes of the folds. In its northern part is located immediately south of the Belezma-Batna mountains. Structural analysis highlights significant tectonic disturbances, oriented in a northwest-southeast direction. A detailed lithostratigraphic examination reveals marly formations interspersed with limestone-rich layers containing Inoceramus. The southern part of Dj. Metlili, particularly the Santonian-Campanian series, unveils three distinct meso-transgressive sequences, linked to sea-level fluctuations associated with sedimentary basin subsidence. The studied area exhibits three distinct facies: one characterized by gray phosphate limestone with crisscrossed stratifications and agitated bioclastic sand, another featuring a mollusk-rich bioclastic limestone indicating a turbulent intertidal environment, and a third presenting a clay limestone bank with fine to medium grains and lumachels rich in oysters and gastropods. The associated grainstone texture in the microfacies suggests an internal platform environment marked by dissolution, bioturbation, and ferruginization. This comprehensive exploration provides valuable insights into the geological history of the region, significantly contributing to our understanding of its evolution over time.

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Paleoekologia i paleośrodowisko późnego kampanu na podstawie wybranych profili z doliny środkowej Wisły

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Zatoń M.

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tom Vol. 51, nr 8

678-684

PL

Trzy odsłonięcia górnego kampanu, należące do trzech kolejnych poziomów amonitowych (Neancyloceras phaleratum, Bostrychoceras polyplocum i Didymoceras donezianum) w dolinie środkowej Wisły, zostały zbadane pod kątem paleośrodowiskowym. Bogata makrofauna ze wszystkich szczebli troficznych, świadczy o spokojnym środowisku, odpowiadającemu dzisiejszej strefie pogranicza wewnętrznego i zewnętrznego szelfu, o normalnym zasoleniu, dobrze natlenionych wodach przydennych i podłożu o zróżnicowanej konsystencji, stwarzającego różnorodnej faunie odmienne nisze ekologiczne.

EN

The paleoecology of macrofauna from three Upper Campanian outcrops in the Middle Vistula valley, belonging to three successive ammonite zones (Neancyloceras phaleratum, Bostrychoceras polyplocum and Didymoceras donezianum), have been investigated on paleoenvironmental ground. The rich macrofauna of all trophic levels indicates the calm epicratonic basin, corresponding to the inner to outer shelf environment, of normal salinity waters, good bottom-water oxygenation and with substrate of varied consistency, providing different niches for diverse fauna.

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Revision of Hamites wernickei Wollemann, 1902 (Cephalopoda, Ancyloceratina) from the classic Lüneburg section (Upper Cretaceous, northern Germany)

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Niebuhr B. , Jagt J. W. M.

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tom Vol. 66, no. 4

627--644

EN

A re-examination of heteromorph ammonites of late Campanian age from the Zeltberg section at Lüneburg has demonstrated that the type series of Hamites wernickei in fact comprises two different species that are here assigned to the nostoceratid Nostoceras Hyatt, 1894 and the polyptychoceratid Oxybeloceras Hyatt, 1900. Nostoceras (Didymoceras) wernickei (Wollemann, 1902) comb. nov., to which three of the four specimens that were described and illustrated by Wollemann (1902) belong, has irregularities of ribbing and tuberculation and changes its direction of growth at the transition from the helicoidal whorls to the hook, which is a typical feature of members of the subfamily Nostoceratinae. Torsion of body chambers is not developed in hairpin-shaped ammonite species, which means that the species name wernickei is no longer available for such polyptychoceratine diplomoceratids. Consequently, the fourth specimen figured and assigned to Hamites wernickei by Wollemann (1902) is here transferred to Oxybeloceras and considered conspecific to material from the Hannover area (Lehrte West Syncline) as O. aff. crassum (Whitfield, 1877). In addition to the "Heteroceras-Schicht des Mucronaten-Senons" of Lüneburg (bipunctatum /roemeri Zone, upper upper Campanian), the geographic range of N. (D.) wernickei probably includes Upper Austria, Tunisia and the Donbass region, while O. aff. crassum is known from the Hannover area (northern Germany), southern France, northern Spain and Upper Austria.