Open AccessSedimentary evolution and stratigraphy of the ~765–740 Ma Kansuki-Mwashya platform succession in the Tenke-Fungurume Mining District, Democratic Republic of the Congo
Author(s) -
Pascal Mambwe,
Franck Delpomdor,
Sébastien Lavoie,
Philippe Mukonki,
J. M. Batumike,
Philippe Muchez
Publication year - 2020
Publication title -
geologica belgica (printed)/geologica belgica (online)
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.227
H-Index - 21
eISSN - 2034-1954
pISSN - 1374-8505
DOI - 10.20341/gb.2020.022
Subject(s) - conglomerate , geology , paleontology , sedimentary rock , sedimentary depositional environment , ecological succession , glacial period , rift , tectonics , structural basin , ecology , biology
The origin of the Mwashya Conglomerate at the base of the Mwashya Subgroup in the Lufilian Belt is uncertain since it is considered as either a tectonic or as a sedimentary breccia. At Tenke Fungurume Mining District (TFMD) in the Democratic Republic of the Congo, the Mwashya Conglomerate is marked by an iron-bearing polymictic conglomerate embedded between the Kansuki and Kamoya formations. In this paper, the Kansuki-Mwashya platform succession at TFMD was investigated to shed light on the origin of this conglomerate, the depositional evolution and the tectonostratigraphic framework of the platform. Lithofacies analysis revealed that the Mwashya Conglomerate is a periglacial olistostrome, which was formed around ~765–745 Ma. A pre-Sturtian age for this conglomerate is supported by the Kamoya Formation, which is here interpreted as a post-glacial cap carbonate sequence. The Kansuki-Mwashya platform succession consists of a protected coastal lagoon adjacent to a tidal flat environment, both bordered by a barrier shoal. This paper concludes that the Kansuki-Mwashya platform succession was driven by rifting pulses, occurring gravity flows on instable slope, superimposed upon the ~750–717 Ma long-lasting Sturtian glacial period.