The geotectonic position of the Madurai Block (south India) within Gondwana, reconstructed from zircon and monazite dating and PT pseudosections

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The project concentrates on the timing of and the geodynamic processes operating during the formation of the Supercontinent Gondwana. The formation and break-up of this supercontinent is somehow related to fundamental changes of the climate, the evolution and the diversification of life on Earth and likely also in the style of plate-tectonic processes in the latest Precambrian. The Southern Granulite Terrane (SGT) of South India is a key area for studying the configuration of Gondwana, as it is situated in a central position within this supercontinent. However, correlations with formerly adjoining crustal fragments of Gondwana are controversial as the geodynamic evolution of the SGT is poorly understood. In particular, the location of Neoproterozoic suture zones is a matter of discussion, as subduction-related former oceanic crust has not yet been recognized. A possible correlation of the SGT with other fragments of Gondwana (Madagascar, Sri Lanka, Antarctica) demands the knowledge of protolith formation ages and of the timing and significance of metamorphic events in the individual crustal domains. This project will elucidate the formation and tectono-metamorphic evolution of the Madurai Block, the largest but least understood crustal domain of the SGT, as well as of the Palghat- Cauvery shearzone system, a presumed Neoproterozoic suture.