Granulite belt

Hoemes S, Van Reenen DC (1992) The oxygen isotopic composition of granuUtes and retrogressed granulites from the Limpopo Belt as a monitor of fluid-rock interaction. Precambrian Res 55 353-364... 

Downes H., Dupuy C., and Leyreloup A. F. (1990) Crustal evolution of the Hercynian belt of western Europe evidence from lower-crustal granulitic xenoliths (French Massif-Central). Chem. Geol. 83(3-4), 209-231. 

LePichon X., Henry P., and Goffe B. (1997) Uplift of Tibet from eclogites to granulites-implications for the Andean Plateau and the Variscan belt. Tectonophysics 273(1-2), 57-76. 

Granulite facies calcite from the Hida metamorphic belt, Japan, exhibits one of the best-documented isotope profiles that is at least in part due to diffusional exchange (Wada, 1988 Arita and Wada, 1990 Graham et al., 1998). The marbles are modally dominated by extremely... 

Zambezi belt Mudzi Suite Felsic granulite Zim-12 36... 

Kamber, B. S., Biino, G. G., Wubrans, J. R., Davies, G. R. Villa, I. M. 1996. Archaean granulites of the Limpopo belt, Zimbabwe one slow exhumation or two rapid events Tectonics, 15,1414-1430. 

In contrast, deep crustal rocks found in metamorphic belts, granulites, are much more varied in composition and include both felsic and mafic varieties (Rollinson St Blenkinsop, 1995). This is consistent with a recent study in the North China Craton which showed that there the lower crust can be divided into two layers - an upper lower crust with velocities between 6.7 and 6.8 km/sec and a lowermost crust, with velocities between 7.0 and... 

Here we explore the idea that the discrepancy between the average composition of the continental crust, which is andesitic, and the modern flux from the mantle to the continental crust, which is basaltic, can be explained in terms of a change in the composition of the crust-mantle flux over time. The hypothesis adopted here is that Archaean crust had a TI G composition, formed from a TTG melt, and was not fractionated into lower basaltic and upper felsic components. Modern crust on the other hand has a basaltic bulk composition but has been modified to andesitic through the fractionation and the removal of a mafic lower crustal component (Rudnick Taylor, 1987). Evidence for the absence of a mafic lower crust in the Archaean comes from Archaean lower crust preserved as granulite terrains, such as the Lewisian (Rollinson Tarney, 2005), the Limpopo Belt (Berger Rollinson, 1997), and the lower crust of the Kaapvaal Craton... 

Arita and Wada (1990) studied the effects of contact metamorphism overprinted on granulite facies marbles of the Hida belt and found that the cores of graphite and calcite retained granulite facies fractionations, but that profound gradients in composition and disequilibrium existed from core to rim within single crystals. 

Cesare, B., Satish-Kumar, M., Cruciani, G, Pocker, S., Nodali, L. (2008) Mineral chemistry of Ti-rich biotite from pegmatite and metapelitic granulites of the Kerala Khondalite Belt (southeast India) petrology and further insight into titanium substitutions. Am. Mineral, 93, 327-388. 

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