Geochemistry and geochronology of calc-alkaline and tholeiitic dykes swarms from the tandilia system, Argentina - Pinese, José Paulo Peccinini; Teixeira, Wilson; Girardi, Vicente Antonio Vitorio; Echeveste, H; Ribot, A; Fernandez, R.; Iacumin, M; Piccirillo, Enzo Michele; Renne, Paul (South American Symposium on Isotope Geology, 1999)