Age, Sr- and Nd- Isotope Systematics and Origin of Two Fluorite Lodes, Sierras Pampeanas, Argentina

GALINDO, C.; PANKHURST, R.J; CASQUET, C.; CONIGLIO, J.; BALDO, E.G; RAPELA, C.W.; SAAVEDRA, J.

INTERNATIONAL GEOLOGY REVIEW

TAYLOR & FRANCIS INC

Lugar: Londres; Año: 1997 vol. 39 p. 948 - 954

0020-6814

Fluorite mineralization at the La Nueva and Bubu mines yields Sm-Nd ages of 131 + 22 Ma and  117 Ma respectively. This the mineralization most probably is related to a late Gondwanian (Lower Cretaceous) extensional and magmatic event that affected the Sierras Pampeanas basement during the opening of the Atlantic Ocean. Hydrothermal fluids involved in the formation of the fluorite probably were of meteoric origin, their isotopic composition (Sr and Nd) resulting largely from the incongruent dissolution of feldspar in the host porphyritic granites