stripes
Alkaline rocks appear to be widespread in the 'Precordillera' (approximately between 39°-33°30'S and 68-69°W) but detailed distributions and descriptions are not available. Phonolite, with aegirine-augite and interstitial nepheline, sodic trachyte, bostonite, tephrite, teschenite, pegmatitic syenite with aegirine and nordmarkite have been described, but appear to be particularly concentrated in the Paramillo de Uspallata.
QUARTINO, B. J. & LLAMBIAS, E. 1964. Synopsis on rocks with alkaline affinities in the Argentine Republic. International Geological Congress, Report of the 22nd Session, India, 16 1-12.
STIEGLITZ, O. 1914. Contribucion a la petrografia de la Precordillera y del Pie de Palo. Boletin, Serie B (Geologia), Direccion General de Minas, Geologia e Hidrologia, 10‚ 1-97