Pan-African shear zones in the Kaoko Belt (Namibia) and links across Southwestern Gondwana: Neoproterozoic evolution and Phanerozoic reactivation

• Grant number: 19/06838-2
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Effective date (Start): June 01, 2019
• Effective date (End): May 31, 2023
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Mario da Costa Campos Neto
• Grantee: Mathias Hueck
• Host Institution: Instituto de Geociências (IGC). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 15/03737-0 - The Rio de La Plata Craton and the Western Gondwana Assembly, AP.TEM

Abstract

This project aims to contribute to the understanding of the tectonic and geodynamic evolution of southwestern Gondwana, from its amalgamation in the Neoproterozoic to its break-up in the Cretaceous. For this, the research will focus on the long-term tectonic activity of the network of shear zones of the Kaoko Belt in northwestern Namibia. The deformation history of these structures during the Pan-African orogenic cycle will be reconstructed using a multi-method geochronological investigation including U-Th-Pb analyses in zircon and monazite, and K-Ar and Ar/Ar geochronology in amphibole, muscovite, biotite and illite fine fractions. The geochronological research will be grounded on detailed structural observations in the field and in microscale, aiming to compare the evolution history of these Shear Zones with the main regional events of the orogeny. The resulting evolution will then be compared with that of equivalent tectonic features in southern Africa and South America, leading to the construction of a tectonic model of the amalgamation of southwestern Gondwana. In addition, this project aims to evaluate the impact of the reactivation of these structures on the regional exhumation during the Phanerozoic, particularly during the period of ca. 400 Myr between the Neoproterozoic orogeny and the Cretaceous continental break-up. In order to do so, different thermochronological methods in the temperature range of 300-100 °C will be combined, focusing both on the direct dating of brittle activity in fault zones (K-Ar in illite fine fractions in fault gouges) and in the reconstruction of the thermal histories of adjacent blocks (Ar/Ar in K-feldspar and (U-Th)/He in zircon, titanite, rutile and apatite). By combining both approaches, the impact of fault activity in exhumation and surface processes will be robustly evaluated. The resulting long-term tectonothermal history of the shear zones and their influence in the regional exhumation will be contextualized and compared with adjacent units in Africa and its South American counterparts, enabling the establishment of correlations across southwestern Gondwana.

Scientific publications

(10)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

HELLER, BEATRIX M.; HUECK, MATHIAS; PASSARELLI, CLAUDIA R.; BASEI, MIGUEL A. S.. Zircon U-Pb geochronology and Hf isotopes of the Luis Alves Terrane: Archean to Paleoproterozoic evolution and Neoproterozoic overprint. Journal of South American Earth Sciences, v. 106, MAR 2021. (19/06838-2, 15/03737-0)

LINO, LUCAS MARTINS; QUIROZ-VALLE, FRANCY ROXANA; VLACH, SILVIO ROBERTO FARIAS; BASEI, MIGUEL ANGELO STIPP; VILALVA, FREDERICO CASTRO JOBIM; HUECK, MATHIAS; MARTINS, JOSE VINICIUS. Deciphering the parent-daughter relationship between Ediacaran high-silica ignimbrites and their complementary silicic cumulates: Insights from zircon trace element composition. CHEMICAL GEOLOGY, v. 635, p. 20-pg., 2023-09-30. (19/17343-4, 15/03737-0, 19/06838-2)

HUECK, MATHIAS; ORIOLO, SEBASTIAN; OYHANTCABAL, PEDRO; HELLER, BEATRIX M. M.; WEMMER, KLAUS; SIEGESMUND, SIEGFRIED; BASEI, MIGUEL A. S.. Archean to early Neoproterozoic crustal growth of the southern South American Platform and its wide-reaching "African" origins. Precambrian Research, v. 369, p. 24-pg., 2022-01-08. (15/03737-0, 19/06838-2)

QUIROZ-VALLE, FRANCY ROXANA; LINO, LUCAS MARTINS; CITRONI, SERGIO BRANDOLISE; BASEI, MIGUEL ANGELO STIPP; HUECK, MATHIAS; VLACH, SILVIO ROBERTO FARIAS; BECKER-KERBER, BRUNO; PRADO, GUSTAVO MARCONDES EVANGELISTA MARTINS. Paleovolcanology, geochemistry, and zircon U-Pb-Hf isotopes of the volcano-sedimentary sequences from the Ediacaran Campo Alegre-Corupa Basin, southern Brazil: Linking volcanism and tectonics during Western Gondwana consolidation. GONDWANA RESEARCH, v. 115, p. 27-pg., 2022-12-20. (15/03737-0, 19/06838-2, 20/11320-0)

GAUTHERON, CECILE; HUECK, MATHIAS; TERNOIS, SEBASTIEN; HELLER, BEATRIX; SCHWARTZ, STEPHANE; SARDA, PHILIPPE; TASSAN-GOT, LAURENT. Investigating the Shallow to Mid-Depth (> 100-300 degrees C) Continental Crust Evolution with (U-Th)/He Thermochronology: A Review. MINERALS, v. 12, n. 5, p. 24-pg., 2022-05-01. (19/06838-2)

LINO, LUCAS MARTINS; QUIROZ-VALLE, FRANCY ROXANA; BASEI, MIGUEL ANGELO STIPP; VLACH, SILVIO ROBERTO FARIAS; HUECK, MATHIAS; WILLBOLD, MATTHIAS; CITRONI, SERGIO BRANDOLISE; LEMOS-SANTOS, DANIEL DO VALLE. Petrogenesis and tectonic significance of two bimodal volcanic stages from the Ediacaran Campo Alegre-Corup ' a Basin (Brazil): Record of metacratonization during the consolidation of Western Gondwana. Precambrian Research, v. 385, p. 24-pg., 2022-12-30. (19/06838-2, 15/03737-0)

HUECK, MATHIAS; WEMMER, KLAUS; KSIENZYK, ANNA K.; KUEHN, REBECCA; VOGEL, NADIA. Potential, premises, and pitfalls of interpreting illite argon dates - A case study from the German Variscides. EARTH-SCIENCE REVIEWS, v. 232, p. 18-pg., 2022-09-01. (19/06838-2)

LARA, HERNAN SILVA; SIEGESMUND, S.; ORIOLO, S.; HUECK, M.; WEMMER, K.; BASEI, M. A. S.; OYHANTCABAL, P.. Reassessing the polyphase Neoproterozoic evolution of the Punta del Este Terrane, Dom Feliciano Belt, Uruguay. INTERNATIONAL JOURNAL OF EARTH SCIENCES, v. 111, n. 7, p. 34-pg., 2022-08-15. (15/03737-0, 19/06838-2)

ORIOLO, SEBASTIAN; SCHULZ, BERNHARD; HUECK, MATHIAS; OYHANTCABAL, PEDRO; HEIDELBACH, FLORIAN; SOSA, GRACIELA; VAN DEN KERKHOF, ALFONS; WEMMER, KLAUS; FOSSEN, HAAKON; DRUGUET, ELENA; et al. The petrologic and petrochronologic record of progressive vs polyphase deformation: Opening the analytical toolbox. EARTH-SCIENCE REVIEWS, v. 234, p. 26-pg., 2022-11-09. (19/06838-2)

LINO, LUCAS MARTINS; QUIROZ-VALLE, FRANCY ROXANA; LOURO, VINICIUS; BASEI, MIGUEL ANGELO STIPP; VLACH, SILVIO ROBERTO FARIAS; HUECK, MATHIAS; MUNOZ, PATRICIO RODRIGO MONTECINOS; CITRONI, SERGIO BRANDOLISE. Structural architecture and the episodic evolution of the ediacaran Campo Alegre Basin (southern Brazil): Implications for the development of a synorogenic foreland rift and a post-collisional caldera-volcano. Journal of South American Earth Sciences, v. 107, APR 2021. (19/06838-2, 15/03737-0)