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The basal portion of the sequences "c" (Late Eifelian to Early Emsian age), ,'D" (Eifelian age), and "E" (Late Eifelian to Late Givetian age) are constituted by shoreface sand bodies. These were deposited in response to the forced regressions displacing the shoreline towards offshore. This process allowed the emplacement of sequences boundaries that truncated the previous shelf pelitic deposits. sequence "F" is constituted by shallow outer shelf deposits, and displays a regressive tending towards the top, ln terms of 2nd order cycles, the deposits of the Furnas and Ponta Grossa formations could be grouped into the same depositional sequence. The Furnas Formation deposits constitute the lowstand systems tract. (1992) .'..."..'..""""""09 -estratþrafia genética e eõtratigrafia de parasseqüências """ """""'23 Tibågi -Telêmacó Borba e Rivadávea """"""""""" 88Fig. '14 -Seção Jaguariafva -sedimentologia e geoquímica ...""""""""""" 90 ?Givetiano. Êstratigrafìa e geoquímica "..'. " """"" """""""""" " 1O2 Fig,21 -Seção Tibagi -Telêmaco Borba -curvas de carbono " -orgånico, ínãice de hidrogênio (lH), Al2O3 e K2O """"" """" """"108 de um corte N-S, enlre os poços 2-TB-1-SP e 2 RS-1-PR """"""'121Fig.27 -Seção de correlação mostrando a distribuiçäo espacial dos atributos estratigráficos das seqüências de A a F, ao longo de um corte N-S, entre os poços 2-CB-1-SP e 2 LS-1-PR """' ""122 um corte W-E, entre os poços 2-AN-1-PR e 1 MO-2-PR """"""""123Fig. 29 -Seção de correlação mostrando a distribuiçäo espacial dos atributos estratigråficos das seqüências de A a F, ao longo de um corte S-N, eñtre os poços 2-UV-1-PR e 2 JT-1-PR """""""" ' 124Fig. 30 -Modelo generalizado para a origem de "offshore bars" em um domíñio marinho-raso """"""""" 137 Wheeler (1958Wheeler ( , 1959 apud Posamentier & Allen, 1994)' Weller (1960 apud Posamentier & Allen, 1994) e Sloss (1962Sloss ( , 1963 (1996) e Sloss (1996), entre outros, nota-se que as principais pecufiaridades da aplicação de práticas da nova Estratigrafia de Seqüências para a cobertura do cráton são largamente problemas criados por d¡ferenças de escala. Esta questão de escala inclui diversos fatores onde as diferenças entre o interior cratônico e outros posicionamentos resultam: (i) das diferenças na ordem de magnitude na taxa de variação da subsidência (centf metros yersus metros por quilômetro); (i¡) hipsometria/batimetria medida em metros e dezenas de metros antes que em centenas ou m¡lhares e metros como bacias extracratônicas e foreland; (iii) espaço de acomodação criado em metros antes que dezenas de metros por milhåo de 3l anos; e (iv) proporção de sedimento preservado perfazendo talvez 10 ou 207o antes que 50 a 100% (Sloss, 1996).No entanto, salienta-se que, embora a Estratigrafia de seqüências tenha sido desenvolvida para ser aplicada em bacias da margem continental, com uma expressäo morfológica de plataforma, talude e bacia, algumas aplicações recentes desta ferramenta na Bacia do Paraná (e.g., Lavina, 1991; Della Fâvera et al., 1992Perinotto, 1992; Della Fáver...

The taxonomy and distribution of Chitinozoa from Silurian (Llandovery) and Lower Devonian strata are reported from the Paraná Basin in southern Brazil and eastern Paraguay. The preCarboniferous sequences of the Paraná Basin in this area are present in three sub-basins viz., the Alto Garças (north) and Apucarana (south) sub-basins in Brazil, and the "East Paraguay Sub-basin" in east Paraguay. There is more similarity in the lithology between the Alto Garças and "East Paraguay" subbasins, than between the former and the Apucarana sub-basin. Llandoverian and Lochkovian to Pragian beds are present in all sub-basins. So far, no Emsian beds have been found in outcrops from the north-northwest margin of the Alto Garças Sub-basin, and no early Emsian beds in the outcrops on the northeast margin. Furthermore, Emsian beds could not be identified from the "East Paraguay Sub-basin" in the present study. The Early Devonian sequence is more complete in the Apucarana Sub-basin. It seems that the Apucarana Sub-basin endured a different evolution compared to the two other sub-basins during the Ordovician, Silurian and lower Devonian. Of the 39 chitinozoan species encountered, 24 species are left in open nomenclature, and the following five species are newly described: Ancyrochitina paranaensis, Angochitina daemoni, Sphaerochitina silurica, Spinachitina harringtoni, and Spinachitina wolfarti. A chitinozoan biozonation, with five zones and three subzones, is proposed for the investigated interval, and compared with the spore zonation. In addition we infer that the Furnas Formation could correspond to two chitinozoan zones found in Bolivia and Argentina (zones of Urochitina loboi and Angochitina aff. A. comosa), ranging in age from late Lochkovian to earliest Pragian. The zones are, from oldest to youngest: total range zone of Belonechitina postrobusta (upper Rhuddanian); total range zone of Conochitina elongata (Aeronian); concurrent range subzone of Spinachitina wolfarti n. sp. and Plectochitina sp. A (lower Aeronian); concurrent range subzone of Conochitina proboscifera and Spinachitina harringtoni n. sp. (upper Aeronian s.l.); concurrent range subzone of Conochitina proboscifera and Desmochitina cf. D. densa (lower Telychian s.l.); concurrent range zone of Salopochitina monterrosae and Conochitina proboscifera (upper Telychianlower Sheinwoodian); total range zone of Urochitina loboi (upper Lochkovian); total range zone of Angochitina aff. A. comosa (lowermost Pragian); total range zone of Ramochitina magnifica (Pragian s.l.), and total range zone of Ancyrochitina parisi (upper Emsian).

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