Isotopic and Diagenenetic constraints of the Neoproterozoic Villa Mónica Formation, Tandilia System, Argentina.

L. GÓMEZ PERAL, D.G. POIRÉ, H. STRAUSS AND U. ZIMMERMANN

Concepción, Chile

Congreso; 10º Congreso Geológico Chileno; 2003

Universidad de Concepción, Chile

The objective of this case study in Argentine Neoproterozoic successions is twofold. On one hand we want to add stable isotope data embedded in a diagenetic study to correlate these outcrops with similar lithologies of the Neoproterozoic world-wide. located in the Province of Buenos Aires, Argentina , which is comprised by an igneous metamorphic basement and a Precambrian and Lower Palaeozoic sedimentary cover. In the Olavarría area, this Precambrian sedimentary succession is composed of the Villa Mónica, Cerro Largo and Loma Negra formations (all of these being constituents of the Sierras Bayas Group) and the Cerro Negro Formation These lithostratigraphic units were grouped (Poiré and Spalletti, 2000) into four depositional sequences: the Tofoletti (I), Malegni (II) and Villa Fortabat (III) sequences, which are Riphean in age, andLa Providencia" sequence (IV) (Riphean-Vendian). We present here the first detailed C-O isotope data for dolimites of the Villa Mónica Formation.