DOI: 10.1016/j.palaeo.2014.04.020
论文题名: Marine vertebrate faunas from the Maastrichtian phosphates of Bengue´rir (Ganntour Basin, Morocco): Biostratigraphy, palaeobiogeography and palaeoecology
作者: Cappetta H. ; Bardet N. ; Pereda Suberbiola X. ; Adnet S. ; Akkrim D. ; Amalik M. ; Benabdallah A.
刊名: Palaeogeography, Palaeoclimatology, Palaeoecology
ISSN: 0031-0182
出版年: 2014
卷: 409 起始页码: 217
结束页码: 238
语种: 英语
英文关键词: Actinopterygians
; Biodiversity
; Maastrichtian
; Morocco
; Reptiles
; Selachians
英文摘要: The Maastrichtian of Bengue´rir (eastern part of the Ganntour Basin, Morocco) consists of about 20. m of phosphates displaying an alternance of soft phosphate levels, marly horizons and hard phosphatic limestones. Isolated teeth of selachians, actinopterygians and marine reptiles are extremely numerous in these phosphatic deposits and have been used for biostratigraphical, palaeodiversity and palaeoecological purposes. Detailed field work allowed to establish an exhaustive list of the Bengue´rir marine vertebrate faunas with their biostratigraphical distribution through five main fossiliferous levels (L6 to L2) spanning all the Maastrichtian. Their importance for biochronological purposes and correlations with other Maastrichtian phosphate deposits worldwide appears noteworthy. The selachians are currently represented by 60 species belonging to 32 genera and 7 orders. Among them, the genus Squalicorax is one of the most interesting concerning high-resolution biostratigraphy and correlations with other phosphate basins because of important rates of change noted between the 5 species recovered from base (e.g. occurrence of S. africanus) to top (e.g. strong representation of S. pristodontus) of the Maastrichtian. The marine reptiles include mainly mosasaurids but also scarcer plesiosaurs, chelonians and crocodyliforms, representing at least 14 taxa. The mosasaurid squamates are the most abundant and diversified with at least 8 species ranging all along the succession. The actinopterygians include mainly teleosts but also pycnodonts, also common in all levels and representing at least 7 taxa. Selachians and reptiles show the same trends, in terms of species richness per level, even if the reptiles are less informative due to a less diversified assemblage. For sharks, L6 and L2 show a high percentage of genera and species occurring only in the layer concerned. The evolution of diversity in actinopterygian fishes is less clear because of their low diversity. The use of dissimilarity indices and agglomerative method underscores two distinct associations: a lower one including the levels L6 and L5, and an upper one comprising the levels L4 to L2. These two associations allow to separate a lower and an upper Maastrichtian level and are important for correlations all around the southern and eastern margins of the Tethys. Another clear faunal turnover occurs between L3 and L2, because of a high appearance rate in L2 (at least in sharks) suggesting an increase in prey abundance, as testified by the rapid increase of marine predator density. Indeed, and through L6 to L2, a possible signal of an environmental damage affecting the predator community can be noted by faunal turnovers, even if no significant change in prey association was clearly detected.From a palaeobiogeographical point of view, the faunal associations of Bengue´rir appear typical of the southern and eastern margins of the Tethys, with several typical species not occurring in the northern Tethys. © 2014. Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/69289
Appears in Collections: 过去全球变化的重建
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作者单位: UMR 5554 du CNRS, Institut des Sciences de l'Evolution, Universite´ Montpellier II Sciences et Techniques du Languedoc, Case courrier 064, place Euge`ne Bataillon, Montpellier cedex 5, France; Sorbonne Universite´s, CR2P, CNRS-MNHN-UPMC, De´partement Histoire de la Terre, Muse´um National d'Histoire Naturelle, CP 38, 8 rue Buffon, Paris, France; Universidad del Pai´s Vasco/Euskal Herriko Unibertsitatea, Facultad de Ciencia y Tecnologi´a, Departamento de Estratigrafi´a y Paleontologi´a, Apartado 644, Bilbao, Spain; Office Che´rifien des Phosphates, Centre Minier de Bengue´rir, Bengue´rir, Morocco; Ministe`re de l'Energie, des Mines, De l'Eau et de l'Environnement, Direction de la Ge´ologie, Rabat, Morocco
Recommended Citation:
Cappetta H.,Bardet N.,Pereda Suberbiola X.,et al. Marine vertebrate faunas from the Maastrichtian phosphates of Bengue´rir (Ganntour Basin, Morocco): Biostratigraphy, palaeobiogeography and palaeoecology[J]. Palaeogeography, Palaeoclimatology, Palaeoecology,2014-01-01,409