Lower Jurassic radiolarians from the Mt. Camicia – Gran Sasso (Central Apennines, Italy)

• Autorzy: Bertinelli, A. , Marcucci, M.
• Konferencja: International Congress on the Jurassic System (7 ; 06-18.09.2006 ; Kraków, Poland)
• Języki publikacji: EN

Abstrakty

EN

Mt. Camicia area belongs to the Gran Sasso Range (Central Apennines, Italy). Well-preserved Middle and Late Hettangian radiolarians have been discovered S-E of Mt. Camicia, in limestone beds that contain also Hetangian ammonites (Bertinelli et al. 2004). These beds are part of a carbonate succession, Late Triassic to Early Liassic in age, which crops out in the eastern part of the Gran Sasso Range. This succession includes euxinic deposits (bituminous dolostones) and other deposits with pelagic characteristics (mudstones and calcarenites). All these deposits developed in a shelf basin bounded by a carbonate platform in which, in the same time interval, were originated the well-known formations of Dolomia Principale and Calcare Massiccio. We describe here the radiolarian assemblages collected together with ammonites in three levels in the ammonite bearing beds, belonging to a section on the eastern side of the “Vallone di Vradda” at Mt. Camicia. The ammonites in the lowest level indicate a Middle Hettangian age, those from the two upper levels indicate Late Hettangian. In this paper we define six new radiolarian species [(?)Anaticapitula parvireticulata, (?)Bipedis venturii, Farcus leonseveroi, Parahsuum vraddense, Squinabolella multispinata, (?)Trexus sphaericus], and describe twenty-seven other species, which we do not establish formally. In the Western Tethys successions the Hettangian radiolarians are rare and have been found together with ammonites only in the Mt. Camicia section (Bertinelli et al. 2004). The ammonite-radiolarian association from the Mt. Camicia area permits to correlate radiolarians with ammonite zonation.

Słowa kluczowe

EN

radiolarians; ammonites; Hettangian; Gran Sasso; Italy

• Czasopismo: Volumina Jurassica
• Rocznik: 2006
• Tom: Vol. 4, no. 1
• Strony: 146-147
• Opis fizyczny: Bibliogr. 1 poz.

Twórcy

autor

Bertinelli, A.

autor

Marcucci, M.

• Dipartimento di Scienze della Terra, Piazza dell'Universita 1, 06123 Perugia, Italy,

Bibliografia

• 1.Bertinelli A., Nannarone C., Passeri L. and Venturi F. 2004. Hettangian ammonites and radiolarians in the Mt. Camicia succession (Gran Sasso, Central Apennines). Rivista Italiana di Paleontologia e Stratigrafia, 110, 1: 87-95.