Bulk geochemistry,Rb-Sr,Sm-Nd,and stable O-H isotope systematics of the Metzimevin high-grade iron ore deposit,Mbalam iron ore district,southern Cameroon

Bulk geochemistry,Sr,Nd,and O-H isotope systematics are reported for the first time on banded iron formation(BIF)-hosted high-grade iron ore at the northwestern segment of Congo Craton(CC).Located in Mbalam iron ore district,Southern Cameroon,Metzimevin iron ore deposit is a hematite-magnetite BIF system,dominated by SiO_(2)+Fe_(2)O_(3)(97.1 to 99.84 wt%),with low concentrations of clastic elements e.g.,Al_(2)O_(3),TiO_(2),and HFSE,depicting a nearly pure chemical precipitate.The REE+Y signature of the iron deposit displays strong positive Eu anomaly,strong negative Ce anomaly,and chondritic to superchondritic Y/Ho ratios,suggestive of formation by mixed seawater-high temperature hydrothermal fluids in oxidising environment.The^(87)Sr/^(86)Sr ratios of the BIF are higher than the maximum^(87)Sr/^(86)Sr evolution curves for all Archean reservoirs(bulk silicate earth,Archean crust and Archean seawater),indicating involvement of continentally-derived components during BIF formation and alteration.TheƐ_(Nd)(t)(+2.26 to+3.77)and Nd model age indicate that chemical constituents for the BIF were derived from undifferentiated crustal source,between 3.002 and 2.88 Ga.The variable and diverse O and H isotope data(−1.9‰to 17.3‰and−57‰to 136‰respectively)indicate that the Metzimevin iron ore formed initially from magmatic plumes and later enriched by magmatic-metamorphic-modified meteoric fluids.Mass balance calculations indicate mineralisation by combined leaching and precipitation,with an average iron enrichment factor of>2.67 and SiO_(2)depletion factor of>0.99.This is associated with an overall volume reduction of 28.27%,reflecting net leaching and volume collapse of the BIF protholith.

Land Use and Land Cover Dynamics in the Eseka Alluvial Gold Mining District, Centre Region, Cameroon

Local populations in Cameroon thrive on forest resources and the flow of ecosystem services they provide are pivotal in sustaining national economy, improving people’s lives, safeguarding biodiversity, and mitigating the impacts of environmental changes. The exploitation of these resources invariably leads to deforestation and forest degradation. This study was designed to evaluate land use land cover change (LULCC) in the Eseka alluvial gold mining district with the aid of Landsat images. In the investigation of forest cover change, four Landsat satellite images for (1990, 2002, 2015 and 2022) were used. Ground-truthing also helped to identify the activities carried out by the local population and to determine agents, drivers and pressures of land use and land cover change. Four main land cover classes namely: forest, agricultural land, settlement/mining camps and water bodies were selected. Between 1990 and 2022, the proportion of forest decreased from 98% to 34% while those of agricultural land and settlement/mining camps increased from 2% to 60% and 0.54% to 6% respectively. Analysis showed ongoing deforestation with forest cover loss of ~98,263 ha in 32 years giving a cover change percentage of 63.94%. Kappa coefficient for the study period ranged from 0.92 to 0.99. Forest cover loss could be attributed to farming activities, wood extraction and alluvial gold mining activities. Economic motives notably the need to increase household income from a frequent demand for farm and wood products in neighbouring towns and the quest for gold were the main drivers of these activities. Hence, this study assesses the impact of human activities from the mining sector on the forest ecosystem in a bid to inform mitigation policies.

Business Clothing For Females: Suitability For Effective Workplace Job Performance in Nigeria

The study investigated business clothing for females that are suitable for effective workplace job performance in Nigeria.It identified fabric characteristics of females’business clothing already used;fabric characteristics needed and deign style preference suitable for females’business clothing for workplace job performance.The study was guided by four research questions and two hypotheses.Population was 4,806 female civil servants in Delta state,Nigeria.Multi-stage sampling technique was utilized to select 136 females.Structured questionnaire was employed to collect data and descriptive statistics and t-test were used for data analysis.Finding showed that cotton,nylon,lacra fabrics,light and medium fabric weight,blue,black,gray,colors,cool texture,rough,smooth surface plain,stripe and flowered design among others were fabric characteristics of business clothing are being used in workplace.But prefer and need cotton,nylon,lacra,light weight,black,blue,gray,brown colours,cool,plain,surface fabrics.Net,organza,heavy weight,white,yellow,toweling fabrics were not preferred.Findings further showed that straight gown,waist flared and gathered gowns,skirt,blouse and suit/jacket,straight,shirt,long sleeves,garment with or without collar,below knee length,peter and convertible collars,among others were highly preferred design styles of clothes.In conclusion,office workers determine what they wear to perform workplace daily jobs promotes self-confidence,comfort,professional worth and productivity.It was recommended that female employees should not downplay appropriate work attires for comfort and organizational productivity to satisfy fashion trends.

An Assessment and Geostatistics of Land-Use and Selected Physico-Chemical Properties of Soils in the Mount Cameroon Area

This work investigated the land-use/land-cover and some physico-chemical properties of the soils of Mt Cameroon and presented same in maps. ArcGIS Pro mapping software, Landsat images, Global Positioning Systems (GPS) coordinates collected from the field combined with updated shape files from competent services were used to produce the location and land-use/land-cover maps. Sixteen topsoil samples (0 - 20 cm) were collected, 4 from each land use/cover category: farmland, forest, plantation and settlement, and analysed for soil pH, cation exchange capacity (CEC), bulk density, moisture content and soil texture, in the laboratory using standard analytical procedures. This data was used to produce spatial distribution maps using ordinary kriging, in ArcGIS Pro. The main terrestrial land use/cover categories comprised of the forest (mangrove, lowland, montane and sub-montane), agroforestry, plantations, grassland, settlement, cropland, shrubby savannah, and bare lava. Bulk density showed the highest values in settlement areas and least values under forest land-use categories. Soil moisture content exhibited a reverse trend compared to that of soil bulk density. Forest soils were the sandiest while soils in plantation agricultural land were the most clayey. The soils were slightly acidic to neutral with soils from agricultural land being more acidic (pH(water) = 5.43). It is discernible from the results that the conversion from forest to other land use/cover classes enhances soil degradation and that soil physico-chemical properties adequately serve as indicators of soil quality in the Mt Cameroon area.

Displaying Water Table Levels, Flow Direction for Predicting Construction Techniques Using Geographic Information: Case Study of Kumba (South West, Cameroon)

The rapid economic growth of the town present the matter of water issue as a problem to human life human life, construction life, agriculture, etc. This study is to predict techniques of foundation construction through the displaying of the water table at the flow direction in the town of Kumba and GIS. It is characterized by a significant research question which is the level of fall and rise in groundwater levels within the town of Kumba and this influence on choice of types of foundation in construction. This study is directed to decision makers, and technicians of the construction field to develop policies facilitating the supervision when building construction foundation by informing about water level depth and its flow direction in the town. To achieve this, depths of static water levels were measured in over 200 randomly selected hand-dug wells in Kumba, after their geolocation and data were collected during the dry season (November and March 2017) and during the rainy season (between April and October 2017). Data were analyzed and treated using Microsoft Excel and GIS software us as Golden Surfer, Global Mapper, and ArcGIS. The results show variations of water level and those areas that may threaten foundation construction. Quarter as Kumba Station, Mile 1, Bulletin Street (Fongong Quarter), and parts of Fiango show that water table is to deep water and proper for the shallow foundation but very hard for water supply through borehole. Groundwater flow direction was revealed to be towards the south and southeastern parts of Kumba. The significant of the study is to propose to the technician the direct application on the field of chosen types of foundations according to the quarter and proposed groundwater supply possibilities.

Nexus between financial innovation and economic growth in South Asia: evidence from ARDL and nonlinear ARDL approaches

This study examined the relationship between financial innovation and economic growth in Bangladesh,India,Pakistan,and Sri Lanka for the period Q11975 to Q42016.The autoregressive distributed lag(ARDL)bounds test was used to gauge long-run relationships,and the nonlinear ARDL(NARDL)test was used to explore asymmetry between financial innovation and economic growth in the sample of Asian countries.The findings from the bounds tests revealed long-run cointegration between financial innovation and economic growth in the sample countries.Furthermore,NARDL confirmed that positive changes in financial innovation linked positively with economic growth and vice versa in the long run.In the short run,however,the study found mixed behaviors in the case of positive and negative changes in financial innovation.To investigate directional causality,the Granger causality test under an error correction model was employed.The Granger causality results supported the feedback hypothesis in both the long run and short run.Thus,financial innovation boosts economic growth in the long run by stimulating financial service expansion,financial efficiency,capital accumulation,and efficient financial intermediation,which are essential for sustainable economic growth.

New detrital zircon U-Pb ages from BIF-related metasediments in the Ntem Complex (Congo craton) of southern Cameroon, West Africa

Banded Iron Formations (BIFs) were formed by contemporaneous events of active sediments supply and the venting of a hydrothermal fluid source at the Mid-Ocean-Ridge. BIFs within the Ntem Complex at the northern edge of the Congo Craton are intercalated with metasandstones and siltstones. SHRIMP U-Pb analysis on detrital zircons obtained from these metasediments gave variable ages from over 3000 Ma to 1000 Ma with the maximum age of deposition clustered around 1200 Ma and the peak of deposition at 1800 Ma. This age range suggested that the sub-basin was opened sometime in the Archean and remained active up till the Neoproterozoic. Zircons with Archean ages have a provenance linked to the charnockitic suite and the high-K granites within the Ntem Complex. The Paleoproterozoic ages are attributed to clastic inputs from the neigbouring Nyong Series west of the Ntem Complex. Also the peak of deposition in the Proterozoic could probably be explained by the globally recognized intense crust-forming processes in the Early Proterozoic time. The provenance of the younger Neoproterozoic ages is tied to various lithologies within the northern mobile belts of the Adamawa-Yade massifs and correlates with Neoproterozoic sedimentation ages in the Yaoundé, Lom and Poli series. The Neoproterozoic ages obtained are comparable to those obtained from metasediments of the Amazonian Craton and provide evidence of Pre-Gondwana assemblage of the Congo and the S?o Francisco Cratons.

Textures and Rare Earth Elements Composition of Banded Iron Formations (BIF) at Njweng Prospect, Mbalam Iron Ore District, Southern Cameroon

The REE signature of banded iron formations (BIF) and martite-goethite mineralization of the Njweng ridge (South Cameroon) are used here to decipher the nature of the ocean during the period of BIF precipitation. The textures of typical BIF categories are also presented as the only sedimentary feature. Two types of BIF facies are present at Njweng: the oxide and silicate facies. These facies show two stages of phase transformations. The first is the transformation of the original magnetite mineral into martite by oxidation resulting in trellis texture;the second is a simultaneous transformation by hydration into goethite and dehydration into martite. The samples typically show LREE depleted patterns relative to HREE, a characteristic similar to that of modern seawater. Also the strong positive Eu anomalies from the samples indicate the involvement of hydrothermal plumes of volcanic origin such as at mid ocean ridges (MOR). Yttrium (Y) has a strong positive anomaly pointing to the transportation of REEs as aqueous complexes within these ancient seas. The BIF samples have no positive Ce anomalies, suggesting that the oceans at that time were more reducing with no Ce fractionation than in present day oceans. The martite-goethite mineralization rather shows a positive Ce anomaly that derived from the enrichment in REE during the weathering of REE-bearing minerals. These results are integrated into existing literature on REE in BIFs worldwide and provide new insights into these heretofore unstudied BIFs of the northern edge of the Congo Craton.

Application of Electrical Resistivity and Chargeability Data on a GIS Platform in Delineating Auriferous Structures in a Deeply Weathered Lateritic Terrain, Eastern Cameroon

Exploration for primary gold in tropical settings is often problematic because of deep weathering and the development of a thick soil cover. In this paper we present the results of both chargeability and resistivity surveys carried out over the Belikombone hill gold prospect (14?00' - 14?25'E, 5?25' - 6?00'N) in the Betare Oya area (eastern Cameroon), where previous soil sampling had identified gold anomalies. The geophysical data were obtained using Syscal Junior 48 resistivity meter and the Schlumberger configuration array for both the vertical electrical soundings (VES) and horizontal profiling. These data were further built into a GIS framework and the continuity of favourable gold-bearing structures at depth modeled using WINSEV, RED2INV and SURFER extensions softwares. IP (Induced Polarization)-chargeability and resistivity data combined, have identified irregular anomalous zones trending NE-SW. This trend is consistent with the attitude of most auriferous quartz veins exposed in artisanal pits and parallel to the regional shear zone system and foliations. The high resistivity anomalies correspond to quartz veins while the relatively high IP anomalies correspond to low sulphide ± gold concentrations in the quartz veins. Modeling IP-chargeability and resistivity data prepared as contours and 3D maps, culminated to the development of an inferred, irregular and discontinuous mineralized body at depths of up to 95 m. The size and shape of this mineralized body can only later be tested by drilling to ascertain the resource.

Financial innovation and economic growth in Bangladesh

Background:This study provides evidence for the financial innovation in the financial system that resulted in the economic growth of Bangladesh from 1980-2016.Methods:To capture the influence of financial innovation on economic growth,we estimated the long-run cointegration by applying Autoregressive Distributed Lag(ARDL)bound testing and Granger causality-based Error Correction Model(ECM)to capture the directional association.Results:The Test of Cointegration satisfied the existence of a long-run association between economic growth and the financial innovation proxies,which were the Domestic Credit to the Private Sector(DCB)as a percentage of the Gross Domestic Product and the Broad-to-Narrow Money(M2/M1)as a percentage of the Gross Domestic Product.Our results showed that in the long run,credit circulation to the private sector and monetary management play important roles in economic growth.We also found that the coefficients of the financial innovation proxy variables were positive and statistically significant both in the short run and long run.We also ran Granger causality tests to investigate the directional effect.This study confirmed the feedback causality between the economic growth and 2 proxies of financial innovation in the short and long run.The gross capital formation and trade openness contribute significantly to explaining the economic growth in Bangladesh.Conclusion:The government of Bangladesh should encourage financial innovation in the financial system,especially at financial institutions,so that access to financial services can easily provide for equitable development.The government should also encourage financial innovation in the capital market,which will assist in raising longterm capital for investment and expedite overall economic growth.

Cashless payment and economic growth

Background:This study examines the effect of adopting cashless payment in five European Union(EU)countries,namely,Austria,Belgium,France,Germany,and Portugal,for the period of 2000-2012.Methods:The within and between effect of adopting cheque payment,telegraphic transfer,card payment and electronic money on these EU’s economy are examined by applying the Pedroni residual cointergration and Panel Vector Error Correction Model(VECM).Results:There is short run causality running from cheque payment to telegraphic transfer and card payment,as well as causality running telegraphic transfer to card payment.In the long run,there is significant effect of adopting cashless payment on the economy of the five EU countries.Conclusions:The adoption of one type of cashless payment will affect another type of cashless payment in the short run.The impact of adopting cashless payment on economic growth can only be significantly observed in the long run.Hence,any policy that promotes cashless payment will not affect the economy immediately.

Chronic hepatitis B-associated liver disease in the context of human immunodeficiency virus co-infection and underlying metabolic syndrome

Globally,a shift in the epidemiology of chronic liver disease has been observed.This has been mainly driven by a marked decline in the prevalence of chronic hepatitis B virus infection(CHB),with the greatest burden restricted to the Western Pacific and sub-Saharan African regions.Amidst this is a growing burden of metabolic syndrome(MetS)worldwide.A disproportionate co-burden of human immunodeficiency virus(HIV)infection is also reported in sub-Saharan Africa,which poses a further risk of liver-related morbidity and mortality in the region.We reviewed the existing evidence base to improve current understanding of the effect of underlying MetS on the development and progression of chronic liver disease during CHB and HIV co-infection.While the mechanistic association between CHB and MetS remains poorly resolved,the evidence suggests that MetS may have an additive effect on the liver damage caused by CHB.Among HIV infected individuals,MetS-associated liver disease is emerging as an important cause of non-AIDS related morbidity and mortality despite antiretroviral therapy(ART).It is plausible that underlying MetS may lead to adverse outcomes among those with concomitant CHB and HIV co-infection.However,this remains to be explored through rigorous longitudinal studies,especially in sub-Saharan Africa.Ultimately,there is a need for a comprehensive package of care that integrates ART programs with routine screening for MetS and promotion of lifestyle modification to ensure an improved quality of life among CHB and HIV coinfected individuals.

Regional Geochemical Stream Sediment Survey for Gold Exploration in the Upper Lom Basin, Eastern Cameroon

Stream sediments are widely employed in reconnaissance exploration for gold especially in areas where outcrops are scarce and the overburden thick such as in the eastern Cameroon goldfields. In this study, 337 stream sediment samples were collected from the Lom river drainage basin. The study aims at identifying the main geological processes affecting the geochemical data from the sediments by considering the multi-elements relationships and spatial features of single elements. The samples were collected in duplicate. One set was panned, gold grains picked and weighed while the second set was wet sieved and the ≤100 microns size fraction retained. This fraction was eventually analyzed for gold by fire assay and a suite of elements by inductively coupled plasma mass spectrometry (ICP-MS). Single element maps were constructed using ArcGIS and the relationship between elements measured using Pearson correlation and principal component analysis (PCA). Gold concentrations in the samples are erratic, most below the detection limit and attain a high of 450 ppm. Five factors are derived from the PCA including single element factors for As and Au reflecting bedrock-hosted mineralization. The Cu-Zn-Y-Nb-Pb factor suggests sulphide mineralization perhaps related to felsic intrusions while the Sr-Ba-La-Ce-Zr factor is linked to lithologic control. These results demonstrate the usefulness of multi-element analysis and data interpretation using GIS tools in the exploration efforts for gold worldwide.

Gold grade variation and stream sediment geochemistry of the Vaimba-Lidi drainage system, northern Cameroon (West Africa)

Stream sediment geochemistry remains a versatile tool in exploration especially in regions where knowledge of the primary mineralization is lacking and the exploration activities are still at reconnaissance stage. In this study, we investigate the concentrations of gold and associated elements in stream sediment samples from the Vaimba-Lidi drainage system in northern Cameroon;a relatively remote area where alluvial gold is worked locally, and exploration activities are at early stage. The main river and its principal first and second order tributaries were sampled, panned for gold grain recovery and the 100 μm size fraction analyzed for Au by fire assay with Ni finish. A suite of other elements were analyzed for by inductively coupled plasma mass spectrometry (ICP-MS). Gold grades estimated by the panning and weighing technique rarely exceed1 g/t while the Au concentrations from chemical analysis range from 3.0 to 354.0 ppm. The spatial distribution of gold and all the other elements are presented as point symbol maps and the data analyzed using multivariate statistics. From the principal component analysis (PCA), the As-Mo-W-Ag as well as the Au-Zn factors point to the presence of primary hydrothermal gold-sulphide mineralization in the area and this can be further investigated. These results highlight the importance of multielement analysis and multivariate statistical interpretation of sediment geochemical data in inferring the nature of the underlying primary mineralization in any region.

Petrochemical Characterization of Two Distinct Types of Dolerites from Bafoussam Area, West Cameroon

Two petrochemical types of doleritic dykes have been distinguished in Bafoussam area: 1) the olivine-bearing dolerites which are the most representative are dark green, showing characteristics of alkaline basalts and, 2) the calcite-bearing dolerites are grayish green, showing characteristics of tholeiitic basalts. The studied dolerites are less differentiated (1 FeOt/MgO 2);they present the evolution of a subalkaline magma following a calc-alkaline series (alkaline dolerites) and the tholeiitic series (tholeitiic dolerite). The chondrite normalized multielement spider diagrams of all the dolerites show a pronounced depletion in Ba, Th, and enrichment in Rb. Their geotectonic context is inferred to be intraplate and the contrast between the two types is probably due to a diverse source: crustal source for calcite-bearing dolerites and mantle source for olivine-bearing dolerites.

Water resources development in Turkey

The Southeastern Anatolia Projec(tGAP),one of the most important projects for developing remarkable natural resources of the world,is accepted as a change for getting benefit from rich water and agricultural resources of the Southeastern Anatolia Region.The GAP Project has been considered as a regional development projects through years,but the dimensions of sustainability,protection of environment and participatory have been attached to the master of the project in recent years.When the GAP Project is completed,the Upper Mesopotomia, the centers of many civilisation,will re-again its importance as it had in the ancient times,and will be alive a center of civilisation.Moreover,when the problem of water shortage and water supplies in the world for the future is kept in mind,the importance of Southeastern Anatolia′s water supplies will be doubled.For this reason,the GAP Project,developed by depending on water and natural resources of the region,will have an important place in the world.The aim of this study is to introduce the region with rich natural resources and the GAP Project.For this reason,firstly,the natural potential of the region will be introduced.Second,the GAP Project will be presented in details.In the third stage,the projects being processed for protecting the natural sources and environment will be analyzed.In the last stage,strategies and policies to develop and to protect the natural resources of the region in short,mid,and long terms will be proposed.

How parents' education and working status affect the nutrition and immunization status of preschool children in India

Objective:The aim of the paper is to see how educational and working status of the parents affect the nutritional and immunization status of preschool children in India.Methods:We have used data of more than 24 000 preschool children spread over different states in India.The data were collected by National Family Health Survey(NFHS-2) in 1998-99.For assessing the nutritional status,only the Z-scores of weight-forheight (WHZ) have been computed and for immunization status,it has been seen whether BCG,DPT3,Polio3 and measles have been administered.Children who fall below -2SD(-3SD) from median are considered to be moderately(severely) malnourished.Results:According to the NFHS-2 data,70%of children are vaccinated by BCG,50%receive the full course of DPT,54%get all the three dozes of polio and only 42%are protected from measles by vaccination in India.The percentages of moderately and severely wasted children in India are 12.1 and 2.8,respectively.There is a marked regional variation of these percentages.Bivariate and multivariate analysis clearly points to the need of educational status of mothers rather than fathers for proper nutritional and immunization status of preschool children.Parents’occupation and working status also have some effect,but not so pronounced as parents’education.Conclusion:The Indian preschool children need particular attention for high risk of wasting and low immunization.The prevalence of malnutrition can be arrested more by improving the mother’s education level rather than their fathers and by raising the standard of living of their house-holds.

The Potential of Quartzitic Veins in SW Cameroon for High-Purity Quartz

High-purity quartz (HPQ), the prime source of silica, is increasingly considered a strategic mineral in the world market because it is the raw material for special applications in high-tech industries owing to its unique physical and chemical properties. The expected growth in demand for HPQ implies that more sources have to be found. This is the primary motivation for this study which targets the Supe area, SW Region of Cameroon. The structural occurrences of quartz veins were mapped and samples collected. The chemical nature and textural features of these samples were subsequently analyzed by X-ray tomography, scanning electron microscopy (SEM), and electron microprobe analysis (EMPA). Three deformation events, D1 - D3 are recorded. D1 is marked by the development of the strong S1 foliation defined by the gneissic layering and schistosity. D2 is a NE-SW ductile to brittle sinistral shear that controlled the formation of tension gashes that served as subsequent pathways for quartz-rich hydrothermal fluids to circulate and eventually precipitate quartz. The presence of rutile, tourmaline, and mica inclusions in the Supe veins affects the purity of the quartz. However, quartz can be treated to improve its quality. Taking into consideration the nine determinant trace elements used to classify HPQ, three (Li, P, and B) are below detection limits, Al concentrations are within the HPQ, quartz market standard, and average natural abundance;Ti values are high above all three standards in all except one sample, while Na, Ca, K, and Fe values fluctuate, thus classifying one of the samples as high purity quartz and the others as low purity quartz. These veins define tension gashes which usually occur in an echelon arrangement covering a large surface area, suggesting that more of such veins probably exist in the Supe area. Consequently, the quality and potential quantity of HPQ veins in this area suggest a high potential for HPQ exploration in the region.

Petrochemistry of Two Magnetite Bearing Systems in the Precambrian Belt of Southern Cameroon

In the past decades, several iron ore occurrences have been discovered in the Precambrian Belt of southern Cameroon, with focus on their economic potential, and little attention on the deposit type. However, few studies have been geared towards understanding the different deposit types within this region. This paper seeks to provide new insight on the different styles of iron ore mineralisation of two potential, yet least studied iron ore deposits in this region in addition to enhancing exploration efforts within the different prospects. Petrology and geochemistry of rock samples from the Binga and Djadom iron prospects in southern Cameroon are investigated. The structural disposition of the prospects was mapped and cores described, sampled and subsequently analysed to enhance the understanding of the alteration mineralogy, ore mineralogy and textural features of the iron-bearing lithologies. Polished thin sections were studied by standard microscopy while the bulk rock geochemistry was determined by X-ray fluorescence (XRF) for major and trace elements. At Binga, the main rock types are magnetite gneisses, amphibolites, quartz-biotite gneisses, and mafic intrusions, while the main rocks encountered at Djadom are magnetite gneisses, amphibolitic BIFs, quartz-biotite gneisses, amphibolites and fault rocks. At both prospects, the target lithology for iron ore is the magnetite gneiss. The magnetite gneisses at the Binga prospect are weakly to moderately foliated, but strongly foliated at Djadom, and both contain fractures that are healed by irregular magnetite. Magnetite is anhedral to euhedral in outline and it is closely associated with amphibole, garnet and pyroxene. Iron content of the magnetite gneisses ranges from 17.44 - 33.40 wt% (at Binga) and 27.73 - 43.39 wt% (at Djadom) and the ore enrichment process involved progressive loss of silica and aluminium. Trace element concentrations show high contents of Ba, Zn, Cu and V but lower abundances of Sr and Zr, as well as low values for Ti in both prospects. At the Binga iron ore prospect, TiO2 and Al2O3 display a linear co-variation with Zr, while in the Djadom prospect, TiO2, Al2O3 and MgO display a negative co-variation with Zr. The origin of the former could be linked to a magmatic fluid-related process, while the genesis of the later is tied to both skarn formation and hydrothermal enrichment.

Characterization of Alluvial Gold Bearing Sediments of Betare Oya District-East Cameroon, Implication for Gold Exploration and Recovery

Field studies (location Au pits, sampling of different layers of sedimentary sequences filling the pits, panning of sediments), litho-stratigraphic investigations, grain size analysis and outlining of depositional conditions revealed a characteristic fining upward sequence in all the sections of 08 Au-pits within the Betare Oya basin. A typical profile is 2.5 to 4.5 m thick and is composed of a 30 to 50 cm organic topsoil layer, underlain by a 1.5 m thick reddish brownish gold free saprolite, which is underlain by 1.5 m sandy section. From litho-stratigraphic investigations and grain size analysis results a quartz dominated gravelly 1.4 m thick layer consisting in boulders (275 mm), cobbles (2-−0.0148x2 + 1.2187x + 2.0344, R2 = 0.6929 (sandy layer);2) y = 0.0617x2 + 1.0849x + 0.8097, R2 = 0.8694 (gravelly layer);and y > R2 is satisfied in both cases. This implies that Au recovery from these layers could be effective through gravity separation using sieves mounted on classifiers of 7 cm (sandy layer) and 10 cm (gravelly layer) diameter.