ESTUDIO PALEOMAGNÉTICO DE VOLCANITAS PLIO-PLEISTOCENAS EN EL SECTOR SEPTENTRIONAL DEL SISTEMA DE FALLAS ANTIÑIR-COPAHUE (CORDILLERA NEUQUINA, ARGENTINA)

PÉREZ, MARTINA; MILANESE, FLORENCIA N.; GEUNA, SILVANA; FRANCESCHINIS, PABLO R.; PUIGDOMENECH, CARLA; SAGRIPANTI, LUCIA; FOLGUERA, ANDRÉS; RAPALINI, AUGUSTO E.

Río de Janeiro

Congreso; LatinMag VII Biennal Meeting; 2023

Asociación Latinoamericana de Paleomagnetismo y Geomagnetismo

A paleomagnetic study was carried out in the northern sector of the NeuquénCordillera (∼37.1°S, ∼70.8°W). The study comprised a total of 25 sampling sites,corresponding to different basaltic flows of the Cola de Zorro Formation (Pliocene -Early Pleistocene; 3.2 – 2.6 Ma). 17 correspond to the Bella Vista section with 145oriented samples, while 8 sites correspond to the Río Huaraco section with 103oriented samples.From the paleomagnetic analysis, normal polarities, likely corresponding to the GaussChron, were found in all sites. The mean paleomagnetic direction obtained for the BellaVista section is: Dec: 0°, Inc: -50°, α95: 7.6°, N=11, while for the Río Huaraco section is:Dec: 354.9°, Inc: -57°, α95: 7.5°, N=8. Both show non-significant tectonic rotations:1.7°±9.7° (Bella Vista) and -3.4°±11.3° (Río Huaraco). After combining these data withsome data from neighbouring sites from Milanese et al. (2023), a clockwise rotation of14.4°±10.3° was obtained for the area delimited by the Trohunco (north), Renileuvú(south) and Neuquén (east) rivers, south of our study localities.