ANISOTROPY OF MAGNETIC SUSCEPTIBILITY ANALYSIS IN CORES OF TUNAS FORMATION (PERMIAN), CLAROMECÓ BASIN, BUENOS AIRES, ARGENTINA: IT RELATION WITH DEPOSITIONAL CONDITIONS

TOMEZZOLI R.N.; ARZADÚN, G; CESARETTI, N.N.; GALLO, L.C.; FEBBO B.; CALVAGNO, J.M.

Rancagua

Congreso; 6° Reunión Bienal de la Asociación Latinoamericana de Paleomagnetismo y Geomagnetismo (LATINMAG); 2019

Asociación Latinoamericana de Paleomagnetismo y Geomagnetismo

Claromecó Basin (Buenos Aires Province, Argentina) is compose by carboniferous-permian rocks that lie on a Paleozoic basement. PANG 0003 well, located in the center of the basin, contain rocks that belong to Tunas Formation. The succession is compose by sandstones, mudrocks, carbonaceous mudrocks, coals and tuffs. The aim of this work is analyze the internal structure in cores through anisotropy of magnetic susceptibility (AMS) studies and relate these parameters with depositional and post-depositional conditions. Additionally, compare the results with previous outcrop data of the Tunas Formation. Standard AMS study was carried out from the base to the top of the well. AMS parameters vary with depth. Magnetic susceptibility (Kmean) present an average of 209 x10-6 SI consistent with the presence of paramagnetic minerals. Anisotropy degree (Pj) increase with depth due to overburden. The shape parameter (T) mainly range from 0 < T < 1 indicating oblate fabric. As the cores are not oriented, Kmax axis lie distributed in the Ecuatorial plane near the horizontal while Kmin axis position are near the vertical perpendicular to the bedding plane with horizontal attitude indicating a triaxial to sedimentary fabric. These results are consistent with those obtained in the outcrops that indicate and attenuating of the efforts upwards of the sequence and toward the foreland basin located to the east. This kind of study allow to increase the knowledge about the basins as Claromecó currently considered as high exploratory risk basin.