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Made available in DSpace on 2018-12-11T16:48:46Z (GMT). No. of bitstreams: 0 Previous issue date: 2017-11-01 This paper shows the importance of the sponge spicules as complement of sedimentary facies analysis in order to reconstruct the hydrach stages involved in island formation in the Upper Paraná River, Brazil. River in the study reach is anabranching with islands of different sizes covered by typical alluvial forest. We noted that the sponge spicules communities vary according to the changes in the environments involved in the island formation processes. The sponges were identified by their microscleres and gemoscleres in optical microscope as Metania spinata, Oncosclera navicella, Oncosclera jewelli, and possibly the genus Corvoheteromeyenia sp. (Ezcurra de Drago, 1979). By correlating the information coming from the sponges and sedimentary facies, it was possible to identify five phases of the island construction and their respective hydrach stages: 1) bar-island channel (Eupotamic stage), 2) blind channel (Parapotamic stage), 3) lake, 4) swamp (both Paleopotamic stage), and 5) forested island (Terrestrial stage). Using 14C dating and rate of sedimentation, we observed that the development of these five phases took ∼900–1000 years. The data also supported the idea that the forest begin to be formed 134–160 years ago. We concluded that sponge is a strong tool on paleoenvironmetal reconstruction when used with another indicators (in this case the facies analysis) and can be applied other fluvial studies as river management especially for long-term impacted systems (by dams) as those of the Paraná River Basin. Universidade Estadual de Maringá/ Pós-graduação Em Ecologia de Ambientes Aquáticos Continentais UEM, Av. Colombo, 5790 Universidade Estadual Paulista/Pós-graduação Em Geociências e Meio Ambiente UNESP, Av. 24 A, 1515 Universidade Do Oeste Do Paraná/Pós-graduação Em Geografia UNIOESTE, R. Pernambuco, 1777 Universidade Estadual Do Paraná/Laboratório de Estudos Paleoambientais da Fecilcam/Lepafe, Av. Comendador Norberto Marcondes, 733 Universidade Estadual Paulista/Pós-graduação Em Geociências e Meio Ambiente UNESP, Av. 24 A, 1515

Sequence stratigraphy, lithostratigraphy and biostratigraphy of the Late Carboniferous/Permian succession of the eastern border of the Parana Basin are organized in the form of a detailed chart in order to provide a useful and updated synthesis of that stratigraphic interval. The traditional lithostratigraphic subdivision is shown together with a third-order stratigraphic framework and a complete biostratigraphic scheme based upon palynomorphs, plants and invertebrate macrofossils. Based on the regional occurrence of features that indicate base level fall and formation of a sequence boundary (e.g., marine to fluvial facies shift, pebbly lags, bonebeds) seven LPTS’s (=Late Paleozoic Third-Order Sequences) were recognized and are shown in the stratigraphic chart, enclosed as an color-printed appendix at the end of the paper. The text includes a brief characterization of the main facies and depositional systems of the lithostratigraphic units, a description of the fossil content of each lithostratigraphic unit, and a characterization in terms of sequence stratigraphy, with a brief description of eight third order sequence boundaries as depicted in the stratigraphic chart, including recent advances on radiometric dating.