CICYTTP   12500
CENTRO DE INVESTIGACION CIENTIFICA Y DE TRANSFERENCIA TECNOLOGICA A LA PRODUCCION
Unidad Ejecutora - UE
artículos
Título:
Palynology and paleoenvironment of the Asselian-?Artinskian Copacabana Formation at Apillapampa near Cochabamba, Bolivia
Autor/es:
DI PASQUO, M.M.; GRADER, G.
Revista:
PALYNOLOGY
Editorial:
AMER ASSOC STRATIGRAPHIC PALYNOLOGISTS FOUNDATION
Referencias:
Lugar: Londres; Año: 2012 vol. 36 p. 264 - 276
ISSN:
0191-6122
Resumen:
New stratigraphic and palynologic study of the lower and Coal members of the Copacabana Formation was carried out at Apillapampa, central Bolivia. Twelve samples yielded 94 species fairly well preserved of which 28 are spores (20 trilete and 8 monolete) and, 58 are pollen grains (18 monosaccate, 8 bisaccate non-striate, and 31 striate and one colpate). Algal remains (4 species), acritarchs (2 species), and scolecodonts (2 species) are also present. One new species, Dictyotriletes cousmineri di Pasquo is here defined and 52 species are recorded here for the first time in this country. A lower assemblage yielded Vittatina and other taxa (e.g., Pakhapites ovatus, Marsupipollenites striatus), which are characteristic of the Asselian-early Artinskian Vittatina costabilis Zone Souza and Marques Toigo (Paraná Basin, Brazil). The upper assemblage is defined by the appearance of several species of Lueckisporites together with other species of Vittatina, Lunatisporites, Pakhapites, Hamiapollenites, Corisaccites, Mabuitasaccites, Striomonosaccites, Striatoabieites, Striatopodocarpites, Weylandites. Abundant monolete (e.g., Polypodiisporites mutabilis, Thymospora rugulosa) and trilete spores (Lundbladispora braziliensis, Lycospora pusilla, Convolutispora uruguaiensis) with subordinate pollen grains (e.g., Pteruchipollenites, Alisporites) are present in the Coal Member. Those species suggest correlation to the middle Artinskian-Wuachiapingian L. virkkiae Zone of the Paraná Basin. Predominantly varied gymnospermous compositions occur in the lower member whereas notably pteridophytes, sphenophylls and lycopods are dominant in the overlying Coal Member. These groups of plants characterized the terrestrial landscape along seaway margins under a paleotemperate climate during the Early Cisuralian and confirm the widespread distribution of the Glossopteris Flora during the Permian in Gondwanaland. Preliminary radiometric data from interbedded tuffs suggest an Asselian??Sakmarian age for the marine Copacabana Formation and a Sakmarian???Artinskian age for the overlying Coal Member. These new data and palynology results will significantly contribute to Permian correlation in central South America.