| Summary: | This work considers with the origin, age and geological environment of the concealed continental crust of Vestfjella, western Dronning Maud Land, Antarctica (WDML). In the Jurassic, the bedrock of Vestfjella experienced the latest major period of extension and rifting. The WDML Jurassic crust has been correlated with the Karoo Large Igneous Province of Africa, and with the Archean and Proterozoic domains, where exposed, of the Archean Kaapvaal Craton and Mesoproterozoic Natal Belt of Africa. The lamproite-hosted xenoliths investigated in this study show metamorphic (including metasomatic) modification from their primary geochemical composition. In the classification of the examined samples, the mineral mode proved to be superior to geochemical classification in protolith identification. The zircon populations of arc affinity metatonalite, quartz metadiorite and metagranite xenoliths record a thermal event at 1150–590 Ma. However, the evolution of the WDML Proterozoic crust began earlier, in the Mesoproterozoic, with arc magmatism at ca. 1450–1300 Ma. The accretion of arc terrains and development of the continental Namaqua–Natal–Maud belt by the Grenvillean-Kibaran orogeny was followed by the break-up of the Rodinia Supercontinent. Granite crystallization at ca. 1100–1090 Ma and at 1050–990 Ma records crustal anatexis, cooling and Neoproterozoic mylonitic deformation. The Proterozoic zircon ages are similar to the crustal domains in the Natal Belt of southern Africa, the Maud Belt of central Dronning Maud Land and remote Mesoproterozoic basement exposed in the West Falkland Islands and Haag nunataks, West Antarctica. The initial εNd (1450) of +7.1 for a pargasite-rich garnet-free metagabbro and the initial εNd (180) of -8.5 for a garnet-bearing metagabbro resemble the isotopic signature of enriched lithospheric mantle and old enriched crust. The present-day Nd isotope composition of these xenoliths conforms to the array of the Triassic Karoo igneous province gabbroic rocks and granulite xenoliths (Proterozoic or ...
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