EMMANUEL ESEYA MENGU JUNIOR - Academia.edu (original) (raw)
Papers by EMMANUEL ESEYA MENGU JUNIOR
Acta geochimica, May 10, 2023
Research Square (Research Square), Oct 6, 2022
Stream sediment geochemical survey was carried out in Boyo area, samples collected and analyzed f... more Stream sediment geochemical survey was carried out in Boyo area, samples collected and analyzed for major, trace and rare earth elements using ICP-MS method. Minerals present in concentrates include gold, zircon, muscovite. The grain size of gold varies from 0.125 to 1 mm, their shape ranges from sub-angular to angular. Gold grains are of two categories: the rst category includes those that are distal to the source, the second category comprises those that are proximal to the source. Fe 2 O 3 , Al 2 O 3 and SO 3 are dominant major elements in stream sediment, sediments are depleted in Nb and Mo. Gold (8440 to > 10000 ppb) has the highest concentration, the Au/Ag (av.: 14.16) ratio exhibits unusual value greater than the value of the upper lithosphere. Sediments ranged into low Ag (0.062 to 8.47 ppm) and high Ag (20 to 51.3 ppm) content, and all of this suggests that the Boyo gold grains result from two sources or derived by two geological processes; the sulphidation was the dominant mechanism of gold ore deposition. Ag-Au-Bi-Cu constitutes the mineralization factor and the chalcophile elements Ag, Bi and Cu serve as potential path nders for Au in the Boyo area. The presence of these elements in the same factor suggests that gold is associated with sulphide minerals. Ag-Hg-W association is related to the hydrothermal alteration of wall rock. The association Ag-Au-Bi-Cu indicates a typical primary mesothermal sulphide ± gold mineralization paragenesis. The Boyo mature sediments derived from intermediate igneous sources that were deposited in a passive margin environment.
Geochemistry: Exploration, Environment, Analysis, 2021
The petrology of Achaean biotite- and amphibole-rich metagranites, the geochemistry of Fe occurre... more The petrology of Achaean biotite- and amphibole-rich metagranites, the geochemistry of Fe occurrences and heavy mineral concentrations in stream sediments from Olounou (Ntem complex) help to constrain their inter-relationships. These metagranites display granoblastic textures outlined by microcline, biotite, amphibole and oxides. Ilmenite (60 to 80%), zircon (15 to 20%) and rutile (1 to 2%) are the mineral fractions in pan concentrates. Two types of Fe mineralization as silicified veins cross-cut the above rocks: hematite ± magnetite quartzites with primary hematite enclosing magnetite relicts contain high average Fe2O3 (69.05 wt%) and TiO2 (0.73 wt%); banded magnetite-rich quartzites with magnetite partially replaced by hematite are characterized by Fe2O3 (52.15 wt%), TiO2 (0.27 wt%), relatively high W (286 ppm) and Ni (108 ppm). Both types have Zn, Cu, Ga contents below 10 ppm, positive Eu anomalies, HREE enrichment over LREEs and low ΣREE (9.76 to 12.07). Iron and SiO2 were der...
Acta geochimica, May 10, 2023
Research Square (Research Square), Oct 6, 2022
Stream sediment geochemical survey was carried out in Boyo area, samples collected and analyzed f... more Stream sediment geochemical survey was carried out in Boyo area, samples collected and analyzed for major, trace and rare earth elements using ICP-MS method. Minerals present in concentrates include gold, zircon, muscovite. The grain size of gold varies from 0.125 to 1 mm, their shape ranges from sub-angular to angular. Gold grains are of two categories: the rst category includes those that are distal to the source, the second category comprises those that are proximal to the source. Fe 2 O 3 , Al 2 O 3 and SO 3 are dominant major elements in stream sediment, sediments are depleted in Nb and Mo. Gold (8440 to > 10000 ppb) has the highest concentration, the Au/Ag (av.: 14.16) ratio exhibits unusual value greater than the value of the upper lithosphere. Sediments ranged into low Ag (0.062 to 8.47 ppm) and high Ag (20 to 51.3 ppm) content, and all of this suggests that the Boyo gold grains result from two sources or derived by two geological processes; the sulphidation was the dominant mechanism of gold ore deposition. Ag-Au-Bi-Cu constitutes the mineralization factor and the chalcophile elements Ag, Bi and Cu serve as potential path nders for Au in the Boyo area. The presence of these elements in the same factor suggests that gold is associated with sulphide minerals. Ag-Hg-W association is related to the hydrothermal alteration of wall rock. The association Ag-Au-Bi-Cu indicates a typical primary mesothermal sulphide ± gold mineralization paragenesis. The Boyo mature sediments derived from intermediate igneous sources that were deposited in a passive margin environment.
Geochemistry: Exploration, Environment, Analysis, 2021
The petrology of Achaean biotite- and amphibole-rich metagranites, the geochemistry of Fe occurre... more The petrology of Achaean biotite- and amphibole-rich metagranites, the geochemistry of Fe occurrences and heavy mineral concentrations in stream sediments from Olounou (Ntem complex) help to constrain their inter-relationships. These metagranites display granoblastic textures outlined by microcline, biotite, amphibole and oxides. Ilmenite (60 to 80%), zircon (15 to 20%) and rutile (1 to 2%) are the mineral fractions in pan concentrates. Two types of Fe mineralization as silicified veins cross-cut the above rocks: hematite ± magnetite quartzites with primary hematite enclosing magnetite relicts contain high average Fe2O3 (69.05 wt%) and TiO2 (0.73 wt%); banded magnetite-rich quartzites with magnetite partially replaced by hematite are characterized by Fe2O3 (52.15 wt%), TiO2 (0.27 wt%), relatively high W (286 ppm) and Ni (108 ppm). Both types have Zn, Cu, Ga contents below 10 ppm, positive Eu anomalies, HREE enrichment over LREEs and low ΣREE (9.76 to 12.07). Iron and SiO2 were der...