Metallogenesis of stratiform copper deposits in the Lufilian orogen, Democratic Republic Congo.

Acknowledgments I Table of contents V List of figures IX List of tables XIII Summary XV 1. Introduction 1 1.1. Sediment-hosted stratiform copper deposits 1 1.2. Stratiform copper mineralization of the Lufilian Orogen 1 1.3. Previous metallogenic models in the Central African Copperbelt 2 1.4. Problem definition 3 1.5. Scope and objectives 3 1.6. Thesis overview 4 2. Regional tectonic and geologic setting 7 2.1. Tectonic setting 7 2.2. Katanga Supergroup 9 2.3. Lufilian Orogeny 13 2.4. Evaporites and breccia 14 3. Methodology 17 3.1. Remote sensing 17 3.1.1. Satellite imagery and pre-processing 17 3.1.1.1. ASTER 17 3.1.1.2. ETM+ 17 3.1.2. Lineament analysis 18 3.2. Sampling, petrography and point counting 19 3.2.1. Lufukwe and Mwitapile 19 3.2.2. Luiswishi and Kamoto 19 3.2.3. Fluid inclusions 20 3.3. Isotope geochemistry 21 3.3.1. Stable S, C, and O isotope analysis 21 3.3.2. Rb-Sr analysis 22 4. Genesis of stratiform Cu mineralization at Lufukwe 23 4.1. Study area and mineralization 23 4.2. Results of remote sensing analysis 24 4.3. Petrography and paragenesis 35 4.4. Point counting 37 4.5. Fluid inclusions 41 4.5.1. Petrography 41 4.5.2. Microthermometry 44 4.6. Discussion 44 4.6.1. Nature of the ore-forming fluids 44 4.6.2. Controls on mineralization and timing 46 4.6.2.1. Structural controls 48 4.6.2.2. Diagenetic controls 48 4.6.2.3. Lithological controls 50 4.6.2.4. Relative timing of mineralization 51 4.6.3. Implications for exploration 52 4.7. Mineralization model 52 5. Genesis of stratiform Cu mineralization at Mwitapile and its relation to Lufukwe 57 5.1. Study area and mineralization 57 5.2. Results of remote sensing analysis 57 5.3. Petrography and paragenesis 60 5.4. Point counting 67 5.5. Fluid inclusion microthermometry 67 5.6. Discussion on the Mwitapile mineralization 71 5.6.1. Fluid evolution 71 5.6.2. Porosity and permeability controls on mineralization 73 5.6.3. Timing of mineralization 73 5.7. Discussion on the sandstone-hosted stratiform Cu mineralizations of the Lufilian Foreland 74 5.7.1. Lufukwe mineralization 74 5.7.2. Comparison between Lufukwe and Mwitapile mineralization 75 5.8. Implications for exploration 77 6. Luiswishi and Kamoto: geology, petrography and fluid evolution 79 6.1. Cu-Co mineralization 79 6.2. Petrography and paragenesis 80 6.3. Fluid inclusions 89 6.3.1. Petrography 92 6.3.2. Microthermometry 93 6.3.2.1. Type-I fluid inclusions 93 6.3.2.2. Type-II and type-III fluid inclusions 96 6.4. Discussion 99 6.4.1. Fluid inclusion microthermometry 99 6.4.2. Cu-Co ore phases 107 6.4.2.1. Hypogene Cu-Co phases 107 6.4.2.2. Supergene mineralization 107 6.4.3. Comparison with earlier microthermometric studies 108 6.4.4. Timing of mineralization 109 6.4.5. Origin of mineralizing/remobilizing fluids 111 6.4.5.1. Pressure–temperature of fluid entrapment 112 6.4.6. Hydrothermal versus syn-sedimentary origin of mineralization 112 7. Luiswishi and Kamoto: isotope geochemistry 115 7.1. Results of stable (S, C, O) and radiogenic (Rb-Sr) isotope analyses 115 7.1.1. Sulfur 115 7.1.2. Carbon and oxygen 115 7.1.3. Rb-Sr 118 7.2. Interpretation and discussion 119 7.2.1. Sources of sulfur 119 7.2.2. Carbon and oxygen isotopes 122 7.2.3. Rb-Sr isotopes 128 8. Comparison with vein-type deposits 135 8.1. Kipushi deposit 135 8.2. Dikulushi deposit 137 8.3. Main mineralization/remobilization phases in the Lufilian Orogen 138 8.3.1. Lufilian Arc 138 8.3.2. Lufilian Foreland 138 9. Conclusions, mineralization models and future perspectives 141 9.1. Conclusions and mineralization models 141 9.1.1. Lufilian Foreland 141 9.1.2. Lufilian Arc (Katanga Copperbelt) 142 9.1.3. Evolution of copper mineralization in the Lufilian Orogen 147 9.2. Future perspectives 147 9.2.1. Geochronology 148 9.2.2. Chemical analysis of fluid inclusions 148 9.2.3. Stable and radiogenic isotope geochemistry 148 9.2.4. Palaeothermometry 149 9.2.5. Remote sensing 149 Appendix A: Results of fluid inclusion microthermometry 151 References 161 Publication list of Hamdy A. El Desouky 181nrpages: 210status: publishe

Two Cu–Co sulfide phases and contrasting fluid systems in the Katanga Copperbelt, Democratic Republic of Congo

The Katanga Copperbelt is the Congolese part of the well-known Central African Copperbelt, the largest sediment-hosted stratiform Cu–Co province on Earth. Petrographic examination of borehole samples from the Kamoto and Luiswishi mines in the Katanga Copperbelt recognized two generations of hypogene Cu–Co sulfides and associated gangue minerals (dolomite and quartz). The first generation is characterized by fine-grained Cu–Co sulfides and quartz replacing dolomite. The second generation is paragenetically later and characterized by coarse-grained Cu–Co sulfides and quartz overgrown and partly replaced by dolomite. Fluid inclusion microthermometric data were collected from two different types of fluid inclusions: type-I fluid inclusions (liquid + vapor) in the quartz of the first generation and type-II fluid inclusions (liquid + vapor + halite) in the quartz of the second generation. The microthermometric analyses indicate that the fluids represented by type-I and type-II fluid inclusions had very different temperatures and salinities and were not in thermal equilibrium with the host rock. Petrographic and microthermometric data indicate the presence of at least two main hypogene Cu–Co sulfide phases in the Katanga Copperbelt. The first is an early diagenetic typical stratiform phase, which produced fine-grained sulfides that are disseminated in the host rock and frequently concentrated in nodules and lenticular layers. This phase is related to a hydrothermal fluid with a moderate temperature (115 to 220 °C, or less if reequilibration of inclusions has occurred) and salinity (11.3 to 20.9 wt.% NaCl equiv.). The second hypogene Cu–Co phase produced syn-orogenic coarse-grained sulfides, which also occur disseminated in the host rock but mainly concentrated in a distinct type of stratiform nodules and layers and in stratabound veins and tectonic breccia cement. This second phase is related to a hydrothermal fluid with high temperature (270 to 385 °C) and salinity (35 to 45.5 wt.% NaCl equiv.). A review of available microthermometric and ore geochronological data of the Copperbelt in both the Democratic Republic of Congo and Zambia supports the regional presence of the two Cu–Co phases proposed in our study. Future geochemical analyses in the Copperbelt should take into account the presence of, at least, these two Cu–Co phases, their contrasting fluid systems and the possible overprint of the first phase by the second one.status: publishe

Stable (C-O) and radiogenic (Sr) isotope geochemistry of the Luiswishi and Kamoto Cu-Co ore deposits, Katanga Copperbelt, Democratic Republic of Congo

Stable and radiogenic isotope geochemistry on carbonates allowed better understanding of the genesis of two main hypogene Cu-Co phases in the Katanga Copperbelt. δ13C and δ18O of dolomites associated with stratiform, early diagenetic, sulphides, belong to the first Cu-Co phase, provide evidence for carbonate precipitation during BSR just before mineralization. Whereas δ13C and δ18O of dolomites associated with stratiform/stratabound, syn-orogenic, sulphides belong to the second Cu-Co phase, indicate carbonate precipitation from a high temperature, host-rock buffered, fluid, possibly under the influence of TSR. Sr isotopes indicate that the mineralizing fluid of the first Cu-Co phase has leached radiogenic Sr and possibly metals by interaction with the granitic basement. However, the fluid responsible for the second Cu-Co phase is most likely a remobilizing fluid that has significantly interacted with the sediments of the Roan Group and possibly did not mobilize additional metals from the granitic basement.status: publishe

Evaluation of the Abu Kharif tungsten ore deposit, North Eastern Desert, Egypt, based on integration of field work, remote sensing and geochemistry

status: publishe

Experimental Optimization with the Emphasis on Techno-Economic Analysis of Production and Purification of High Value-Added Bioethanol from Sustainable Corn Stover

Bioethanol-derived biomass is a green sustainable source of energy that is highly recommended as an efficient alternative to the replacement of fossil fuels. However, this type of bioethanol production is always expensive with very low bioethanol concentration. Therefore, this work aims to represent a facile and green approach for bioethanol production with high concentration and purity as well as reasonable cost from corn stover (CS). The goal of this study is to characterize CS and its treated samples with maleic acid (CSM) using various characterization analyses, such as proximate and ultimate analysis, HHV, TGA, FTIR, SEM, and CHNS. The bioethanol production stages: Pretreatment, enzymatic degradation, fermentation, and finally bioethanol separation and purification via the pervaporation process, which have been investigated and optimized are associated with the economic analysis. The optimum operating condition of the pretreatment process was 2% maleic acid, 1:20 solid-to-liquid ratio at 45 psi, 120 °C, and 1 h of operation in the autoclave. This process contributes to 53 and 45% lignin and hemicellulose removal, 98% cellulose recovery, and a glucose yield of 741 mg/dL. The yeast isolate succeeded in the production of 1230 mg/dL of bioethanol. This isolated yeast strain was close to Pichia nakasei with a similarity of 98%, and its amplified 18S rRNA gene sequence was deposited in GenBank with the accession number MZ675535. Poly (MMA-co-MA) membrane was synthesized, characterized, and its efficiency for increasing the bioethanol concentration was evaluated using the integrated pervaporation technique. The techno-economic analysis is presented in detail to evaluate the process profitability, which achieves a considerable profit for the whole duration of the project without any losses as it reaches a net profit of USD 1 million in 2023, reaching USD 2.1 million in 2047 for a company with a capacity of 32 thousand tons per year. The sequential strategy offers a promising approach for efficient bioethanol production under mild and environmentally friendly conditions that enable its implication industrially

Experimental Optimization with the Emphasis on Techno-Economic Analysis of Production and Purification of High Value-Added Bioethanol from Sustainable Corn Stover

Bioethanol-derived biomass is a green sustainable source of energy that is highly recommended as an efficient alternative to the replacement of fossil fuels. However, this type of bioethanol production is always expensive with very low bioethanol concentration. Therefore, this work aims to represent a facile and green approach for bioethanol production with high concentration and purity as well as reasonable cost from corn stover (CS). The goal of this study is to characterize CS and its treated samples with maleic acid (CSM) using various characterization analyses, such as proximate and ultimate analysis, HHV, TGA, FTIR, SEM, and CHNS. The bioethanol production stages: Pretreatment, enzymatic degradation, fermentation, and finally bioethanol separation and purification via the pervaporation process, which have been investigated and optimized are associated with the economic analysis. The optimum operating condition of the pretreatment process was 2% maleic acid, 1:20 solid-to-liquid ratio at 45 psi, 120 °C, and 1 h of operation in the autoclave. This process contributes to 53 and 45% lignin and hemicellulose removal, 98% cellulose recovery, and a glucose yield of 741 mg/dL. The yeast isolate succeeded in the production of 1230 mg/dL of bioethanol. This isolated yeast strain was close to Pichia nakasei with a similarity of 98%, and its amplified 18S rRNA gene sequence was deposited in GenBank with the accession number MZ675535. Poly (MMA-co-MA) membrane was synthesized, characterized, and its efficiency for increasing the bioethanol concentration was evaluated using the integrated pervaporation technique. The techno-economic analysis is presented in detail to evaluate the process profitability, which achieves a considerable profit for the whole duration of the project without any losses as it reaches a net profit of USD 1 million in 2023, reaching USD 2.1 million in 2047 for a company with a capacity of 32 thousand tons per year. The sequential strategy offers a promising approach for efficient bioethanol production under mild and environmentally friendly conditions that enable its implication industrially