1,2 , M. Humayun 1 , H. Downes 3 , S. Singletary 4 , J. A. Van Orman 5 and S. B. Jacobsen 2 1 National High Magnetic Field Laboratory and Department of Geological Sciences, [email protected]; 2 Department of Earth and Planetary Sciences, Harvard University; 3 School of Earth Sciences, Birkbeck University of London; 4 Department of Natural Sciences, Fayetteville State University; 5 Departm...

Halliday, A.N., Davidson, J.P., Hildreth, W. and Holden, P., 1991. Modelling the petrogenesis o1 high Rh/Sr silicic magmas. In: A. Peccerillo (Guest-Editor), Geochemistry of Granitoid Rocks. Chem. Geol., 92: 107-114. Rhyolites can be highly evolved with Sr contents as low as 0.1 ppm and Rb/Sr > 2,0(t0. In contrast, granite batholiths are commonly comprised of rocks with Rb/Sr < l 0 and only rar...

The Precambrian Dullstroom Formation of South Africa, which is predominantly composed of basaltic andesites interbedded with subordinate sedimentary and felsic volcanic strata, represents the ®rst phase of an extended period of magmatism that was responsible for the Bushveld Magmatic Province, including the extrusive Rooiberg Group and the intrusive Bushveld Complex. New geochemical and isotopi...