Teaching Documents by JOK MICHAEL APIOTH MAYOL
This work investigates the role of mantle metasomatism in the genesis of calc-alkaline magmas, us... more This work investigates the role of mantle metasomatism in the genesis of calc-alkaline magmas, using a geochemical, petrological, and geodynamic approach. Mantle metasomatism, defined as the chemical modification of the mantle by fluids or melts derived from subducted slabs, occurs predominantly in subduction zones. Two forms are recognized: cryptic metasomatism, which alters mantle chemistry without forming new minerals, and modal metasomatism, which introduces hydrous phases such as amphibole and phlogopite.
The nature of metasomatic agents depends on pressure-temperature conditions, ranging from aqueous fluids at low temperatures to silicate melts and supercritical fluids at higher pressures. Their interaction with peridotites modifies mantle mineralogy and trace element composition, lowers the solidus, and facilitates partial melting. Resulting calc-alkaline magmas are enriched in large ion lithophile elements and light rare earth elements, with characteristic negative anomalies in high field strength elements. Isotopic ratios of Sr, Nd, and Pb further reflect slab-derived contributions.
This study highlights mantle metasomatism as a key process in arc magmatism, explaining the geochemical and isotopic signatures of calc-alkaline rocks and offering insights into the geodynamic evolution of convergent margins.
This study focuses on the optimization and valorization of low-grade phosphate horizons in the lo... more This study focuses on the optimization and valorization of low-grade phosphate horizons in the lower layer 2 Panel 5 of the Benguérir mine, located in the Ganntour basin in Morocco, a region that is home to one of the world's largest sedimentary phosphate reserves. The research addresses the challenge of valorizing phosphate layers with BPL content below the profitability threshold, focusing on the lower part of layer 2 (C2i). Fieldwork consisted of systematic geological surveys, stratigraphic logging, and targeted sampling from exploratory drilling.
Laboratory analyses included chemical assays (BPL, SiO₂, MgO, CO₂, Cd) and grain size characterization. Spatial data processing and geostatistical modeling were performed using ArcGIS and Surfer software to produce thematic maps (structural, isopach, and isoteneur) to support resource evaluation.
The results reveal that C2i phosphates are heavily diluted by siliceous and carbonate minerals, requiring enrichment processes such as washing, screening, and size separation to improve P2O5 content to marketable levels. The study demonstrates that tailored enrichment techniques can significantly improve the economic potential of low-grade layers, contributing to sustainable resource use and extending the operational life of the mine. These results provide a methodological framework for similar phosphate deposits worldwide, balancing geological constraints and industrial enrichment strategies.
Conference Presentations by JOK MICHAEL APIOTH MAYOL
This Presentation explains two complementary techniques—remote sensing and geophysics—for mineral... more This Presentation explains two complementary techniques—remote sensing and geophysics—for mineral resource exploration in the central Jebilets region, between Sidi Mansour and Oulad Dlim, north of Kitara. Remote sensing enabled the detection of major structural lineaments (N-S to NNE-SSW, and a secondary N70 set), the production of a geological facies map consistent with existing cartography, and the identification of hydrothermal mineral concentrations such as iron oxide, dolomite, and silica. The geophysical survey, based on electrical resistivity, revealed four E-W trending sections showing anomalies at depths of 20–100 m over widths of around 200 m. Integrating remote sensing with geophysical data highlighted low-resistivity zones linked to hydrothermal alteration, potentially indicating secondary minerals such as pyrite, chalcopyrite, or other sulfides. These findings provide valuable insights into hydrothermal fluid pathways and mineralization processes in the study area.
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Teaching Documents by JOK MICHAEL APIOTH MAYOL
The nature of metasomatic agents depends on pressure-temperature conditions, ranging from aqueous fluids at low temperatures to silicate melts and supercritical fluids at higher pressures. Their interaction with peridotites modifies mantle mineralogy and trace element composition, lowers the solidus, and facilitates partial melting. Resulting calc-alkaline magmas are enriched in large ion lithophile elements and light rare earth elements, with characteristic negative anomalies in high field strength elements. Isotopic ratios of Sr, Nd, and Pb further reflect slab-derived contributions.
This study highlights mantle metasomatism as a key process in arc magmatism, explaining the geochemical and isotopic signatures of calc-alkaline rocks and offering insights into the geodynamic evolution of convergent margins.
Laboratory analyses included chemical assays (BPL, SiO₂, MgO, CO₂, Cd) and grain size characterization. Spatial data processing and geostatistical modeling were performed using ArcGIS and Surfer software to produce thematic maps (structural, isopach, and isoteneur) to support resource evaluation.
The results reveal that C2i phosphates are heavily diluted by siliceous and carbonate minerals, requiring enrichment processes such as washing, screening, and size separation to improve P2O5 content to marketable levels. The study demonstrates that tailored enrichment techniques can significantly improve the economic potential of low-grade layers, contributing to sustainable resource use and extending the operational life of the mine. These results provide a methodological framework for similar phosphate deposits worldwide, balancing geological constraints and industrial enrichment strategies.
Conference Presentations by JOK MICHAEL APIOTH MAYOL