TAFONOMIA COMPARADA DOS CONULATAE (CNIDARIA), FORMAÇÃO PONTA GROSSA (DEVONIANO), BACIA DO PARANÁ, ESTADO DO PARANÁ

摘要: A high resolution taphonomic analysis of the Conulatae from Ponta Grossa Formation, Devonian (Pragian-Emsian), Parana Basin, State is presented. The study based on occurrences found in rocks that are lithostratigraphically coeval to Jaguariaiva Member. data gathered indicate conulariids [ Conularia quichua Ulrich Steinmann & Doderlein 1890 and Paraconularia africana (Sharpe 1856)] preserved according three distinct classes. These classes were established to: a- three-dimensional distribution fossils matrix; boccurrence isolated or clustered specimens; c- degree bioturbation; d- type deformation showed by thecae. Taphonomic class 1 includes conulariids, vertically oriented bedding. Commonly, they inflated, nonfragmented, massive laminated siltstones, sometimes with discrete ichnofossils. 2 encompasses inclined Specimens assigned this intensely bioturbated siltstones including traces fossils, such as Zoophycus . 3 represented horizontally bedding, four subclasses (I IV) complex history. Vertically (class 1) interpreted situ (autochthonous) occurrences, which mud clouds during storm events abruptly bury living organisms. Inclined 2) deeply 3-I) autochthonous parautochthonous occurrences. Horizontally inflated thecae, close association brachiopod-dominated pavements ( i.e ., Australospirifer inheringi Kayser 1900) hummockies 3-II) allochthonous records. Conversely, incomplete strongly compressed fine-grained sediments 3-III) climbing ripples 3-IV), record history, exposure at sediment/water interface, transport loss skeletal hard parts. Conulariids exhibit nonrandom stratigraphic Sequence B. In geological section Jaguariaiva, State, preferentially two well-defined intervals, located 29 32 44 48 meters top Furnas Formation. Layers 1), representing obrution deposits distal tempestites, a few centimeters below marine flooding surfaces characterize these intervals. Finally, support idea conulariid thecae not structures, but rather flexible ones thus able folding.