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TitreThe Buday'ah Formation, Sultanate of Oman: A Middle Permian to Early Triassic oceanic record of the Neotethys and the late Induan microsphere bloom
AuteurBaud, A; Richoz, S; Beauchamp, B; Cordey, F; Grasby, S; Henderson, C M; Krystyn, L; Nicora, A
SourceJournal of Asian Earth Sciences vol. 43, 2012 p. 130-144,
Séries alt.Secteur des sciences de la Terre, Contribution externe 20100414
Documentpublication en série
Mediapapier; en ligne; numérique
Sujetsbassins; développement du bassin; bassins sédimentaires; distribution de fossiles; fossiles; stratigraphie; paléontologie; Mésozoïque; Trias; Paléozoïque; Permien
Illustrationslocation maps; photographs; stratigraphic columns; block diagrams
ProgrammeBassin sédimentaire Sverdrup, GEM : La géocartographie de l'énergie et des minéraux
Résumé(disponible en anglais seulement)
The Middle Permian to Lower Triassic Buday'ah section, exposed in the Oman Mountains, is the first deepsea section to be described in the Neotethys. The oceanic sediments were deposited along the southern Tethys margin in the newly formed Hawasina Basin. It is one of the few placeswhere true Tethyan Permian radiolarites are exposed that allow the documentation of CCD evolution through time. The succession begins as oceanic crust pillow basalt with red ammonoid-rich pelagic limestone occurring both above and within inter-pillow cavities; the new occurrence of Clarkina postbitteri hongshuiensis indicates a late Capitanian age for the carbonate. The sharp change to overlying late Capitanian to Changhsingian radiolarite reflects rapid subsidence about 10 Myrs after initial continental breakup that resulted in the formation of the Neotethys Ocean. New conodonts indicate that the Permian - Triassic boundary succession occurs in the first platy lime mudstone beds above a Changhsingian siliceous to calcareous shale unit. The platy lime mudstone beds include an Upper Griesbachian bloom of calcite filled spheres (radiolarians?) that marks a potential world-wide event. New conodonts indicate an early Olenekian age for overlying grey papery limestone that are devoid of both macrofossils and trace fossils indicating that recovery from the Late Permian extinction has not yet progressed within this deep-water environment. d13Corg, isotope values have not been disturbed and they show a negative shift just below the Permian - Triassic transition and a second one at the parvus zone level above. The Buday'ah succession may represent the most distal and probably deepest Permian and Lower Triassic depositional sequence within the basin.