IGEBA   23946
INSTITUTO DE GEOCIENCIAS BASICAS, APLICADAS Y AMBIENTALES DE BUENOS AIRES
Unidad Ejecutora - UE
artículos
Título:
Late Pennsylvanian aridification on the southwestern margin of Gondwana (Paganzo Basin, NW Argentina): A regional expression of a global climate perturbation
Autor/es:
GULBRANSON, E.; MONTAÑEZ, I.; TABOR, N; LIMARINO, C.
Revista:
PALAEOGEOGRAPHY PALAEOCLIMATOLOGY PALAEOECOLOGY
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Lugar: Amsterdam; Año: 2015 vol. 417 p. 220 - 235
ISSN:
0031-0182
Resumen:
Paleosols of the PaganzoGroup preserve a shift fromthe cool climate of the glaciated high-latitudes of Gondwanato a long-termaridification punctuated by shorter-term fluctuations inmoisture regime in the late Carboniferous.A quantitative reconstruction of paleoclimate inferred from the major element chemistry of paleosol horizonsand the stable isotope geochemistry of soil-formed minerals and organic matter indicates that the climate variedsubstantially during deglaciation along the southwestern margin of Gondwana in the Middle Pennsylvanianincluding two geologically abrupt shifts to notably drier conditions. This dynamic climate terminates in a drysubhumid moisture regime characterized by steppe/dry scrub floral provinces. Quantitative estimates of netprimary production during the post-glacial interval inferred from paleosol major element geochemistry areconsistentwith a mesic soil temperature regime, in agreementwith paleotemperatures inferred frompedogenicgoethite δD and δ18O. Contemporaneous aridification iswell expressed in paleotropical continental records withMiddle to Late Pennsylvanian aridification coincident with an abrupt evolutionary change in many marine andterrestrial species. The synchrony of aridification between the high and low paleo-latitudes and concomitantmajor restructuring of some ecosystems suggests that a paleoclimate change of global nature occurred duringthe Moscovian and Kasimovian.