Project 6183
Application of non-traditional isotopes in the petrogenesis of granitic rocks
GACR205/07/0992
Project leader: Mgr. Vojtěch Janoušek, Ph.D.
Abstract
Despite the two centuries of intense studies, the key questions regarding the source and origin of granitods persist. Application of non-traditional isotope systems, e.g. Li and B, are likely to shed a fresh light onto these long-standing controversies. The problem is that our understanding of their behaviour is still fragmentary and data scarce.The proposal invokes a series of case studies on a range of well-documented granitoid suites in Bohemian Massif and Western Carpathians. Detailed geochemical and Li–B–O–Sr–Nd work should yield constraints on Li and B isotope distribution and genesis of various granitoid rocks (I, S and A type granites, ultrapotassic rocks, leucogranites and pegmatites).
Evaluated will be the source control (enriched mantle, lower crust, metasediments) and the subsequent development of the magmas (fractional crystallization, assimilation, hybridization). Furthermore, the project should provide a badly needed Li–B reference dataset for granitic rocks. To be expected are also important constraints on geotectonic development of eastern part of the Variscan Belt.
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