The Late Neoproterozoic/Early Palaeozoic evolution of the West Congo Belt of NW Angola: geochronological (U-Pb and Ar-Ar) and petrostructural constraints


Delphine Bosch, Géosciences Montpellier, UMR-CNRS 5243, Université de Montpellier 2, Place Eugène Bataillon, 34095 Montpellier Cedex 05, France. Tel.: +467143267; fax: +467143603; e-mail:


Terra Nova, 24, 238–247, 2012


U-Pb zircon and Ar-Ar amphibole and biotite ages from rocks of the West Congo Belt of Angola indicate that this area underwent two main deformation events of amphibolite facies grade at c. 540 and 490 Ma, which were followed by tectonically assisted exhumation during eastward thrusting of the hinterland domain onto the foreland domain. High-grade conditions in the West Congo Belt are 20–40 Ma younger than in the Ribeira–Araçuai Belt of Brazil, its South American counterpart, or than in the westernmost Kaoko Belt of Namibia, its African correlative. In the present state of knowledge, a more appropriate counterpart to the southern part of the West Congo Belt may be restricted to the Cabo Frio Terrane in the eastern Ribeira Belt, which yields a broadly similar evolution.