Palaeo-proxies recording primary signature of C-O isotope data from the Valanginian Mulichinco Formation, Neuquén Basin, Argentina: first results

GOMEZ PERAL, L.E.; SCHWARZ, E.; SIAL, A.N.; SPALLETTI, L.A.

Medellin

Simposio; VIII South American Symposium on Isotope Geology (SSAGI); 2012

A Valanginian δ13C positive excursion has been widely recognized in European basins, but its identification in South American coeval strata has not been equally reported. In the Neuquén Basin (Argentina), a shallow-marine Valanginian succession is mostly composed of interbedded siliciclastic and carbonate deposits (the Mulichinco Formation). This contribution firstly presents petrographic studies and geochemical results in two phases of the carbonate beds (oyster and micrite). Subsequently, we present preliminary C-O isotope curves for the unit (~ 300 m thick).