Geophysical anomalies in the Sierra del Padre and Sierra del Tala, San Luis province, Argentina: evidences of buried mafic-ultramafic rocks.

JOSÉ KOSTADINOFF,; ERNESTO BJERG,; DANIEL GREGORI,; SERGIO DELPINO,; LUIS DIMIERI; ARIEL RANIOLO,; ABERRA MOGESSIE,; GERARD HOINKES,; CHRISTOF HAUZENBERGER,; ANYA FELFERNIG,

JOURNAL OF SOUTH AMERICAN EARTH SCIENCES

Elsevier

Lugar: Oxford; Año: 2001 vol. 14 p. 271 - 276

0895-9811

This paper presents the results of a geophysical study of the southern portion of the Sierra Grande de San Luis, San Luis Province, Argentina. A 26 mGal amplitude Bouguer anomaly (Charlone anomaly), measuring 40 km long by 7 km wide, between Sierra de los Padresand Zanjitas reflects the presence of high-density rocks located at approximately 2000 m depth. Geophysical models based on more than 300 gravimetric, magnetometric, and geological field measurements and observations suggest that the mafic-ultramafic belt of Sierra Grande deSan Luis continues south of San Luis. The low magnitude of the terrestrial magnetic field anomalies indicates that these mafic-ultramafic rocks do not carry a base metal sulfides (BMS) mineralization. The Charlone gravimetric anomaly is generated by a belt of mafic-ultramaficrocks whose amplitude is comparable with that responsible for the Virorco-Las Aguilas gravimetric anomaly.