Author(s)

Ndèye Penda Dione¹, Moustapha Diagne¹, Mouhamadou Bachir Diouf¹, Mamadou Fall¹, Pierre Giresse²

¹Department of Geology, Faculty of Science and Technology, University Cheikh Anta Diop of Dakar, Dakar, Senegal.
²CEFREM Université de Perpignan UPVD, Perpignan, France.

The Tobène deposit forms, with those of NdomorDiop and KeurMor Fall, the large phosphate deposit of Ta?ba. The Tobène site has been the subject of lithostratigraphic, biostratigraphic, mineralogical, petrographic and geochemical studies. The lithostratigraphic and biostratigraphic studies dated the series from Lutetian to Bartonian composed of five lithological units, which are assembled by [1] in three formations. The mineralogical study shows three groups of minerals associated with the different phosphatic facies identified in the various sectors of Tobène: 1) characteristic minerals of sedimentological conditions; 2) minerals of diagenetic origin; 3) minerals of alteration. The petrographic study allowed an inventory of the constituting visible grains of the microfacies as well as the different phases of diagenetic and post-diagenetic transformations that may have affected them. It thus appears that the phosphatic ore of Tobène has undergone an extensive diagenesis (compaction, dissolution-recrystallization, epigenesis) to which a relatively intense ferruginization has been added.

Tobène, Phosphate, Petrography, Mineralogy, Alteration

Penda Dione, N. , Diagne, M. , Bachir Diouf, M. , Fall, M. and Giresse, P. (2018) Petrography and Mineralogy of the Eocene Phosphate Deposit of Tobène (Taïba, Senegal). Journal of Geoscience and Environment Protection, 6, 193-209. doi: 10.4236/gep.2018.65016.