The marine upper Palaeozoic in Patagonia (Tepuel–Genoa Basin, Chubut Province, Argentina): 85 years of work and future prospects

PAGANI MARÍA A; TABOADA, ARTURO CÉSAR

PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY

ELSEVIER SCIENCE BV

Lugar: Amsterdan; Año: 2010 p. 130 - 151

0031-0182

Argentina is a special place to study Late Palaeozoic life and environmental change because of the excellentexposures of Late Palaeozoic sedimentary sequences. In particular, Patagonia has an almost continuous LatePalaeozoic succession containingwell-preserved faunal assemblages characterized by both strong endemismanddistinctive palaeobiogeographic links to Australia and northeast Asia. In this contribution an overview of thecurrent knowledge of the invertebrate faunas of Patagonia and their biostratigraphic and palaeobiogeographicsignificance are presented, alongwith comments on the future prospects of research in the light of newfindings.The Late Palaeozoic outcrops in central-western Patagonia belong to the Tepuel–Genoa Basin (Chubut province,Argentina), then located in southwestern Gondwana during the Late Palaezoic. In this basin the succession isN6000m thick, and constitutes a continuous and complete succession from the Lower Carboniferous to lowerPermian. As such, it has the potential to serve as an important reference section for regional and intercontinentalcorrelations. The marine Late Palaeozoic of Patagonia has yielded abundant and well-preserved representativesof most invertebrate groups: brachiopods, bivalves, gastropods, cephalopods, hyolithids, pelmatozoans,ostracods and cnidarians. Recently, studies of the Patagonian faunas have resulted in different opinions onthe ages of the faunas. Biostratigraphic correlation is complex due to strong faunal provincialism. For this reason,there are several hypotheses concerning the biostratigraphic zonation in the basin. Since 1920, when studies ofLate Palaeozoic strata in Patagonia were first carried out, numerous papers on stratigraphic, palaeogeographicand taxonomic subjects have been published, but our knowledge of Carboniferous–Permian fossils from theTepuel–Genoa Basin is still incomplete. At present, we are attempting to integrate and calibrate the differentfaunal associations with a view to achieving a unified biostratigraphic biozonation scheme and hence a muchimproved understanding of the palaeobiogeographic relationship of Patagonian faunas with those from westernArgentina and other continents. Currently, detailed stratigraphic and palaeontological research is being done inthe type section of the Tepuel–Genoa Basin. The aim of our studies is to integrate all partial sequences exposedthroughout the basin and to propose a biostratigraphic chart based on key invertebrate taxa. Once this goal isachieved, a global correlation can be conducted, especially with other sections in Gondwana and the Arctic.