Journal of

GEOsciences

  (Formerly Journal of the Czech Geological Society)

Original Paper

Bernard Bonin

Death of super-continents and birth of oceans heralded by discrete A-type granite igneous events: the case of the Variscan-Alpine Europe

Journal of Geosciences, volume 53 (2008), issue 3-4, 237 - 252

DOI: http://doi.org/10.3190/jgeosci.036

Granitoids occupy large areas of the Variscan-Alpine Europe. The specific group of A-type granites identifies post-collisional (post-orogenic) and anorogenic geodynamic settings. Post-orogenic igneous provinces are emplaced during the very last episodes of supercontinent amalgamation. Anorogenic igneous provinces accompany continental break-up and predate the development of new oceanic basins. Though not voluminous compared with the other granite types, A-type granites substantiate critical periods of the life of supercontinents.
Their ages of emplacement in the Variscan-Alpine Europe span the entire Cambrian-Triassic time interval. They are not random, however, and correspond to discrete episodes. Two major age groupings, both with a c. 60 My duration, are distinguished. The Early Cambrian-Early Ordovician period corresponds to Pannotia amalgamation, followed by its break-up and the development of the Rheic-Proto-Tethys Ocean. The Late Carboniferous-Early Triassic period corresponds to Rheic closure and Pangaea amalgamation, followed by its break-up and the development of the Neo-Tethys Ocean. Devonian-Early Carboniferous A-type igneous episodes, scarce in Europe but widespread in Central Asia, accompanied the development of the Palaeo-Tethys Ocean.