Cromo espinelos de Las Águilas, provincia de San Luis, como indicadores tectónicos.

FERRACUTTI, G; BJERG, E A; MOGESSIE, A

Rio Cuarto

Congreso; VII Congreso de Mineralogia y Metalogenia; 2004

The hills of La Huerta and Valle Fertil, wich belong to the Western Pampean Ranges in the Province of San Juan, NW Argentina, mainly consist of metagabboic to metadioritic rocks that intruded the Proterozoic basement in the Early Middle Ordovician (Famat <!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} @page Section1 {size:21.0cm 842.0pt; margin:70.9pt 3.0cm 70.9pt 3.0cm; mso-header-margin:35.45pt; mso-footer-margin:35.45pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> The mafic-ultramafic rocks of the Las Aguilas deposit occur 30 kin. NE of San Luis city, Central Argentina. Two groups of spinels were identified. Both have homogeneous chromian-alumina cores, with one of them generally displaying cores with higher AII(Cr+AI) and chromian-aluminian chromite rims, associated to orthopyroxenites, while the other group occur in dunites with ferritchromites and chromian-magnetite rims. Based on spinel chemical features and comparison with spinels from ophiolites, the Las Aguilas deposit is considered to belong to the worldwide well defined group of mafic-ultramafic layered continental intrusives.