RT Journal Article
T1 Pre-Mesoproterozoic crustal framework and Mesoproterozoic evolution of the SW Angolan Shield: structural, geochemical, and isotopic insights from the Kunene Complex and surrounding basement
A1 Merino Martínez, Enrique
A1 Ferreira, Ezequiel
A1 Valverde Vaquero, Pablo
A1 Rodrigues, José Feliciano
A1 Escuder Viruete, J.
A1 García Lobón, J.L.
A1 Beranoaguirre, A.
A1 Feria, María del Carmen
A1 Fuenlabrada Pérez, José Manuel
A1 Galindo Francisco, María Del Carmen
AB The southwestern Angolan Shield hosts the Earth’s largest Mesoproterozoic massif-type anorthosite complex (up to 53,500 km2), the Kunene Complex (KC). This complex is the result of a long-lived (∼200 Ma) episodic emplacement of coalescent magmatic pulses. The recent acquisition of multidisciplinary data during the PLANAGEO project has significantly enhanced our understanding of the Precambrian crustal framework from the southwestern Angolan Shield. Combined multi-isotope, structural and geophysical data reveals distinctive crustal zones in the southwestern Angolan Shield that clearly influenced KC’s emplacement within a back-arc setting. The spatio-temporal arrangement of KC pulses suggests westwards magma migration within a complex contractional regime involving large strike-slip systems. A long-lasting and extensive accretionary orogen was responsible for the tectono-thermal activity recorded during most of the Mesoproterozoic. Crustal thinning and partial melting of isotopically heterogeneous lower-crustal sources through mantle upwelling promoted the episodic felsic magmatism contemporaneous with the KC. Crustal contamination processes are evident in gabbro-anorthosites, indicating mantle metasomatism and interaction with wall-rocks and granite melts during ascent, upwelled by lateral-driven forces. Deposition of extensive metasedimentary sequences (<1.26 Ga) covering the KC, along with 1.23–1.07 Ga sublithospheric and mantle-derived magmatism, indicate a shift from a compressional to an extensional regime during late-Mesoproterozoic times. Regional correlations with other Mesoproterozoic units in African and Brazilian counterparts suggest a shared geological evolution, despite potential differences in tectonic setting. These findings supports a refined geological model for the Mesoproterozoic evolution of the southwestern part of the Congo Craton.
PB Elsevier
SN 0301-9268
YR 2025
FD 2025-12
LK https://hdl.handle.net/20.500.14352/131221
UL https://hdl.handle.net/20.500.14352/131221
LA eng
NO Merino-Martínez, E., Ferreira, E., Valverde-Vaquero, P., Rodrigues, J. F., Escuder-Viruete, J., García-Lobón, J. L., Beranoaguirre, A., Feria, M. D. C., Rey-Moral, C., Silva, P. B., González-Cuadra, P., Sousa, J. C., Potti, J., Máximo, J., Gutiérrez-Medina, M., Gumiel, J. C., Galán, G., Mochales, T., Manuel, J., … Galindo, C. (2025). Pre-Mesoproterozoic crustal framework and Mesoproterozoic evolution of the SW Angolan Shield: Structural, geochemical, and isotopic insights from the Kunene Complex and surrounding basement. Precambrian Research, 431, 107937. https://doi.org/10.1016/j.precamres.2025.107937
NO Government of the Republic of Angola
NO IGME-CSIC
DS Docta Complutense
RD 19 mar 2026