Lithostratigraphy and Characterisation of Paleocene Limestones for Optimal Exploitation (Senegal, West Africa): Comparative Study of the Bandia and Popenguine Quarries

Limestones of different facies in the Senegal basin are most commonly used as aggregates, regardless of their petrographic properties. These differences may influence their behaviour. The aim of this paper is to study the stratigraphy and characterise the limestones of the Bandia and Popenguine quarries. Sampling and geochemical and geotechnical characterisation were carried out on these limestones. The results show the presence of several very different facies in the Paleocene formation. The geochemical study shows that the Bandia limestones (Bd2) have the highest CaCO3 percentages (98.54%) and the highest SiO2 percentages were recorded in the Popenguine limestones (Pop2). The study also gives MDE values of 22.38 and LA of 22, which are acceptable for use in road construction. It is important to carry out a complete study in order to select the right materials for optimal use.

Mineralogical Characterization of Heavy Mineral Concentrates from Senegalese Great Cost by Using Qemscan and SEM

The heavy mineral sands of Senegal are exploited to extract titanium oxides and zircon. Mining is carried out first by means of a floating dredge and concentration plant which produces a heavy mineral concentrate (HMC) containing on average 78% titanium oxides, 11% zircon and a set of silicate and alumino-silicate minerals. This heavy mineral concentrate is then treated by gravity, magnetic and electrostatic separation to produce titanium oxide concentrates (ilmenite, leucoxene, rutile) and three varieties of zircon concentrates (Premium zircon, standard zircon and medium grade zircon standard). In this study, we describe the various mineral concentrates in terms of mineralogical assemblages, and textural variability within grains, using Qemscan and Scanning Electron Microscopy. The titanium oxide concentrates are differentiated by their TiO2 content and vary from ilmenite to rutile. The zircon concentrates are characterized by the presence of impurities in the zircons, which consist in numerous inclusions of titanium oxides and silicate minerals. The mineralogical characteristics determined by scanning electron microscopy and by Qemscan showed great variability within the grains themselves. Heavy minerals contain many mineral inclusions and show strong chemical zoning.

Monazite Recovery by Magnetic and Gravity Separation of Medium Grade Zircon Concentrate from Senegalese Heavy Mineral Sands Deposit

Gravity, magnetic and electrostatic separation methods allowed to obtain different titanium oxide concentrates (ilmenite, leucoxene, rutile) and different varieties of zircon concentrates (premium zircon, standard zircon, medium grade zircon standard) from Senegal’s heavy mineral sands. During mining separation, monazite, which is a paramagnetic mineral, was found in a non-negligible concentration of 0.57 wt% on average in the medium grade zircon standard which also contains 37.96 wt% zircon and 44.46 wt% titanium oxides. Magnetic and gravity separation tests were carried out on the Medium grade zircon standard (MGZS) to produce a monazite concentrate at Eramet Ideas laboratory. Magnetic separation at 1.5 teslas intensity resulted in the recovery of 94.8% of the monazite from the MGZS. Gravity separation also recovered 76.6% of the monazite from the MGZS. The combination of these two treatment methods can thus produce three concentrates from MGZS (a monazite concentrate, a zircon concentrate, and a titanium oxide concentrate).

Stratigraphy of the MSGBC Basin in the Western Part of Thies by Pixelation and Website Simulation (Senegal, West Africa)

During this research work we developed another approach to digital mapping using the pixelation technic. This unprecedented digital mapping of the basin MSGBC in Senegal required the compilation of numerous geological data consisting of seismic lines and oil and hydraulic log reports. These spatial reference data include geological information from the surface to the top of the Campanian. The mapped terrains are composed of the Post-Paleocene Complex (PPC), the Paleocene, the Maastrichtian, and the Campanian. The nearest neighbor method has been used to establish the spatial distribution of the different geological formations. Histograms of values were used to determine the confidence intervals of the mapping. They were used to locate areas of low relative error and to apply the 3D digital mapping technique. For instance, Diender Guedj has been mapped at 1:25,000. The result of this mapping is extracted and processed using the DBMS (MySQL) software. The latter allowed both to determine Paleocene gab and update data. And then the database is processed. The programming languages PHP and Javascript have been used to simulate a website.