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The genesis of Indo-Sinian granitic plutons with peraluminous and potassium-rich affinities from Hunan Province, China has been investigated by numerical modeling using the numerical code FLAC. On the basis of the regional geological evolution in South China, we employed a realistic numerical model in an attempt to unravel the influences of basaltic underplating and tectonic crustal thickening on the crustal anatexis. Heat production derived from basaltic underplating (e.g. ca. 220 Ma gabbro xenoliths) can result in dehydration melting of fluid-bearing minerals in crustal rocks such as gneisses and metapelites, but its effect is limited in a relatively short time span (5?15 Ma) and on a small scale. Accordingly, it is very difficult for basaltic underplating to generate the large-scale Indo-Sinian granitic bathliths unless voluminous mafic magmas had been underplated at the lower/middle crust during this period. Alternatively, crustal thickening induced by tectonic compression can also lead to geotherma
The genesis of Indo-Sinian granitic plutons with peraluminous and potassium-rich affinities from Hunan Province, China has been investigated by numerical modeling using the numerical code FLAC. On the basis of the regional geological evolution in South China, we employed a realistic numerical model in an attempt to unravel the influences of basaltic underplating and tectonic crustal thickening on the crustal anatexis. Heat production derived from basaltic underplating (eg ca. 220 Ma gabbro xenoliths) can result in dehydration melting of fluid-bearing minerals in crustal rocks such as gneisses and metapelites, but its effect is limited in a relatively short time span (5-15 Ma) and on a small scale. had been underplated at the lower / middle crust during this period. Alternatively, crustal thickening induced by tectonic compression can also lead to geotherma