Alkaline vulcanism from Nordpatagonia, Río Negro province, Argentina.

LABUDIA, C; NTAFLOS, TH; BJERG, E A; GÜNTHER, M; DINGELDEY, CH; BJERG, E A

Salta

Congreso; XIV Congreso Geológico Argentino; 1999

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;} --> Detailed geochemical and isotopic studies were carried out on volcanic rocks along an E-W profile from Ramos Mexias to Comallo in Rio Negro Province, Patagonia, 41 °S. Rocks are of Pliocene to Quaternary age consisting of trachybasalts and tephrites/basanites that carry upper mantle and crustal xenoliths. Crustal xenoliths are more common in Queupuniyeu.