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

LUCÍA E. GÓMEZ PERAL, ERNESTO SHWARZ, ALCIDES N. SIAL & LUIS A. SPALLETTI

Medellin

Congreso; VIII Simposio Sudamericano de Geología Isotópica; 2012

Universidad Nacional de Colombia

A Valanginian d13C positive excursion has been globally recognized, but its identification in South American coeval strata has not been extensively 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 diagenetic characterization of carbonate beds and geochemical results in two of their main phases (oyster and micrite). Subsequently, we present preliminary C-O isotope curves for the unit (~ 300 m thick).