INVESTIGADORES
ESCAPA Ignacio Hernan
congresos y reuniones científicas
Título:
AN EARLY PERMIAN LYCOPOD FOREST FROM PATAGONIA, ARGENTINA, AND ITS PALEOCLIMATIC IMPLICATIONS
Autor/es:
CÚNEO, RUBÉN; GALLEGO, JULIETA; ESCAPA, IGNACIO
Lugar:
Denver
Reunión:
Congreso; GSA Annual Meeting; 2013
Institución organizadora:
Geological Society of America
Resumen:
Lycopods were uncommon plants at the beginning of the Permian in
Gondwana. Reasons for that were mostly of climatic origin linked with
the glaciation event that occupied extended regions of the southern
land-masses. Western Gondwana, Patagonia in particular, seems to have
been exceptionally different in that regard, with inferred macroclimatic
conditions that allowed the growth of diverse and dense lycopod
communities. The case of the Rio Genoa Formation is perhaps one of the
most iconic examples on this respect, as one of the few in situ lycopod
forest was formerly described from this unit. We provide new information
regarding the possible structure of this plant community by means of
recent calculations of density, height, biomass, etc. As a result, the
lycopod forest of the Rio Genoa Formation occurs as a relatively dense
monotypic community (260 to 520 ind.ha-1), with individual
trees reaching diameters up to 60 cm and calculated heights from 20 to
30 m. Lycopod plant communities in the Early Permian Río Genoa Formation
grew along upper delta plain deposits, and two subtypes can be
identified, i.e. those associated with swampy environments, and those
growing on wet areas with no stagnant waters. The association of this
type of plants with other climatic sensitive groups including
tree-ferns, sphenophytes, etc., is highly contrasting with coeval
Gondwana counterparts, and suggests atypical climatic conditions in
Western Gondwana by the beginning of the Permian, when glacial
conditions were still prevailing in most parts of the supercontinent.