Petrology and Geochemical Characteristic of Granitoids From Guéra Massif in the Central Part of Chad: An Example of Mixing Magmas

Diontar Mbaihoudou, Kwékam Maurice, Fozing Eric Martial, Kagou Dongmo Armand and Tcheumenak Kouémo Jules

Earth Science Research, 2020, vol. 9, issue 2, 66

Abstract: The granitoids of Guéra Massif are composed of biotite-granite, amphibole-biotite granite and gabbro-diorite and commonly contain micro granular mafic enclaves which vary from monzogabbro to syenite composition. They are metaluminous, high-K calc-alkaline to shoshonitic series. Gabbro-diorite rocks are magnesian while amphibole-biotite granites are magnesian to ferroan, and biotite granites are ferroan. They are enriched in LREEs relative to HREE and display negative anomalies in Nb, Ta and Ti. Fields relationships, petrology and geochemistry indicate that mixing and mingling processes could be more relevant for the genesis of granitoids associated to fractional crystallization. Thus, the presence of mafic enclaves of gabbro-diorite composition in the granites, the resumption of alkaline feldspar xenocrystals in the gabbro-diorites, as well as the linear correlation between the granites and the gabbro-diorites and the intermediate position of the mafic enclaves between the two formations, enable us to propose magmatic mixing as the major process that presided over the evolution of the Guéra granitoids. The delamination of the continental lithosphere during the post-collisional phase of the Pan-African orogeny would have caused the partial melting of the subduction-modofied mantle and lower continental crust and thus produced the magmas of the Guéra granitoids.

Date: 2020
References: View complete reference list from CitEc
Citations:

Downloads: (external link)
http://www.ccsenet.org/journal/index.php/esr/article/download/0/0/43200/45244 (application/pdf)
http://www.ccsenet.org/journal/index.php/esr/article/view/0/43200 (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:ibn:esrjnl:v:9:y:2020:i:2:p:66

Access Statistics for this article

More articles in Earth Science Research from Canadian Center of Science and Education Contact information at EDIRC.
Bibliographic data for series maintained by Canadian Center of Science and Education ().