Episodic and short-lived granitic pulses in a post-collisional setting: evidence from precise U–Pb zircon dating through a crustal cross-section in Corsica

摘要: Abstract In western Corsica, a large granitoid batholith was emplaced during Carboniferous and Permian times. These rocks display an evolution through time from high Mg–K calc-alkaline, to then alkaline affinities. Moreover, the magmatic processes can be observed at different crustal levels. New precise Isotope Dilution Thermo-Ionisation Mass Spectrometry (ID-TIMS) U–Pb dating suggests that granite magmatism in Corsica did not simply reflect continuous thermal of thickened crust. A timing for post-collisional is documented with four distinct short-lived episodes, respectively 345, 338, 305 280 Ma, separated by periods inactivity. magma pulses variable Nd isotopic signatures related mantle–crust interactions. Granite generation emplacement strongly connected tectonic activity lithosphere. An increasing contribution depleted mantle last igneous event. This interpreted materials lower crust, which enhanced heat flow triggered partial melting previously underplated mafic rocks. marks onset new geodynamic cycle characterised extensional regime, preluding opening Alpine orogenic tract.