INGEIS   05370
INSTITUTO DE GEOCRONOLOGIA Y GEOLOGIA ISOTOPICA
Unidad Ejecutora - UE
artículos
Título:
ISOTOPIC TRACING OF THE PARANÁ RIVER, ARGENTINA
Autor/es:
PANARELLO, H.O.; DAPEÑA, C.
Revista:
INTERNATIONAL ATOMIC ENERGY AGENCY Technical Document (Tecdoc)
Editorial:
INTERNATIONAL ATOMIC ENERGY AGENCY
Referencias:
Lugar: Viena, Austria; Año: 2008
ISSN:
1011-4289
Resumen:
The Río de la Plata estuary is the collector of a vast drainage basin of about 3.1·106km2 .  There are many tributaries to the estuary but the Paraná and Uruguay rivers discharge directly more than the 99% of the average 24000 m3/s. We study the stable isotope compositions since 1997.  From 120 isotopic pairs, it could be established that 18O and 2H exhibit a cyclical pattern with maxima in November and minima in May.  Values are in correspondence with the ITCZ position.  When it is located near10º N, the rain over the basin is lower and hence the isotopic composition of both elements is less depleted.  Conversely, when the ITCZ moves southwards, the pluviosity increases leading to 18O and 2H to more negative values.  This signal is recorded with a delay of  ca 4 month in the estuary.  The derivate magnitude, deuterium excess, showed important variations, from 1 to 18 per mil, being related the higher values to positive ENSO (El Niño) and the lower to negative ENSO (La Niña).