stripes
This complex forms an approximately circular structure about 5 km in diameter emplaced in Precambrian metamorphic rocks which are domed and surrounded by Silurian and Permo-Carboniferous sedimentary rocks. The principal rock types are pyroxenite and aegirine-nepheline syenite, which are intruded by trachyte and phonolite dykes and thin veins of apatite-magnetite sovite. The country rocks have been subjected to potassium fenitization.
MARIANO, A.N. and DRUECKER, M.D. 1985. Alkaline igneous rocks and carbonatites of Paraguay. Abstracts with Programs, Geological Society of America, 17: 166.
MARIANO, A.N., personal communication, 1985.
PALMIERI, J.H., PLUGFELDER, P.M. and CUEVAS, F.K. 1974. Contribucion a la geologia regional del area NE'A - Cerro Sarambi, Departamento de Concepcion (Paraguay). Revista Sociedad Cientifica, Paraguay, 14: 63-6.
PALMIERI, J.H., personal communication, 1981