Tonalite-trondhjemite-granodiorites

TTG, Archean tonalite-trondhjemite-granodiorite PRB, Peninsula Ranges Batholith GRC, Glenelg River Complex LFB, Lachlan Fold Belt Hbl, hornblende granite Crd, cordierite grantie. 

Martin H. and Moyen J.-F. (2002) Secular changes in tonalite-trondhjemite-granodiorite compositions as markers of the progressive cooling of the Earth. Geology 30, 319-322. 

Smithies R. H. (2000) The Archean tonalite-trondhjemite-granodiorite (TTG) series is not an analogue of Cenozoic adakite. Earth Planet. Sci. Lett. 182, 115-125. 

The mafic rocks are komatiites, basalts, gab-bros and dolerites, and the felsic rocks are both tonalite-trondhjemite-granodiorites (TTG) and granodiorite-granite-monzogranites (GGM). Analyses of galena and K-feldspar provide initial Pb isotopic compositions, as they contain little or no uranium. 

Granitoid magmas in the compositional range Tonalite-Trondhjemite-Granodiorite. These are the magmas which have built the Archaean continental crust... 

The dominant rocks of the Earth s early continental crust are the felsic magmas of the tonalite-trondhjemite-granodiorite suite, or the TTG suite, as it is known (Rollinson, 2006). Compared to average crust TTGs are more felsic, more sodic and have a lower mg-number, and are clearly different from average "andesitic" crust (Table 4.2, Fig. 4.10). This implies that the magmatic flux across the Moho has changed with time (Kemp St Hawkesworth, 2003). 

The dominant rock-types of the Archaean continental crust are those granitoids of the tonalite-trondhjemite-granodiorite (TTG)... 

Jackson, M.D., Gallagher, K., Petford, N., and Cheadle, M.J., 2005. Towards a coupled physical and chemical model for tonalite-trondhjemite-granodiorite magma formation. Lithos, 79, 43-60. 

Martin, H., Smithies, R.H., Rapp, R., Moyen, J.-F., and Champion, D., 2005. An overview of adakite, tonalite-trondhjemite-granodiorite (TTG) and sanukitoid relationships and some implications for crustal evolution. Lithos, 79, 1-24. 

Fig. 3.21 The classification of plutonic igneous rocks by Streckeisen (1967, 1976) is based on the modal abundances of quartz (Q), alkali feldspar (including albite, An < 5%) (A), and plagioclase (An >5%) (P). The fields have been numbered in order to identify the rock types that correspond to them 1. quartz, 2. alkali granite, 3. granite, 4. granodiorite, 5a. quartz diorite (trondhjemite), 5b. quartz diorite (tonalite), 6. alkali syenite, 7a. quartz syenite, 7b. syenite, 8a. quartz monzonite (adamellite), 8b. monzonite, 9a. monzodiorite, 9b. monzogabbro, 10. diorite/gabbro (Adapted from Streckeisen 1967)...

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