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Mining Implication in the Geochemical Exploration of Fluvial Sediments of the East Nyambaka Volcanic Zone (Adamawa-Cameroon)

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International Journal of Geosciences 2022年第5期13卷 361-381页

作者： Roland William Edima Yana augustin désiré balla ondoa Lise Carole Okomo Atouba Mefire Aminatou Fagny Armel Zacharie Ekoa Bessa Nkouandou Oumarou Faarouk Centre for Geological and Mining Research Garoua Cameroon department of Earth Sciences Faculty of Sciences University of Ngaoundere Ngaoundere Cameroon Higher Teacher Training College of Bertoua University of Ngaoundere Bertoua Cameroon department of Earth Sciences Faculty of Sciences University of Yaounde I Yaounde Cameroon

Geochemical characterization in stream sediments from Nyambaka locality was carried out on ten samples collected from the study area watershed. The distribution of trace metals in the sediments showed that some lithophiles (Be, Sc, V, Cr, Sr, Th, U), chalcophiles (Cu, Zn, Ga, As) and siderophiles (Mn, Co, Ni, Mo) have high average contents in the sediments compared to their average concentration in the upper crust. From the factorial analysis of the components, the total variance explained made it possible to represent and capture the main information on the data and to represent them in a graphical frame. Thus, using this graphical frame, the trace elements were divided into four groups opposed to each other. They show an enrichment of stream sediments in group 1 (Cr, Cu, Mn, Be, Ni, Co, Zr, Sr, Ba, Mg) and group 2 (Mo, As, Hg, V, Ag) elements more than group 3 (Ga, Sc, U) and group 4 (Au, Th). Rare earth analysis indicates a high abundance of Lanthanide (28.1 ppm to 42.4 ppm), a high concentration of light rare earth (LREE), and depletion of heavy rare earth (HREE). The variable LREE/HREE (7.24 LREE/ HREE 12.22) and (La/Yb)N (6.70 (La/Yb)N 11.72) ratios suggest an effect of heterogeneous sorting of heavy minerals with variable enrichment of dense and resistant minerals.

关键词： Stream Sediments Geochemistry Mining Exploration Volcanic Zone East Nyambaka Cameroon

diagenetic and Geochemical Study of Sediments from the Cretaceous Basin of Babouri-Figuil (North-Cameroon)

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International Journal of Geosciences 2021年第4期12卷 404-417页

作者： augustin désiré balla ondoa Alexis Nyangono Abolo Léopold Ekengele Nga Appolinaire Tograne Simon Ngos III Elvine Paternie Edjengte doumo Armel Zacharie Ekoa Bessa department of Earth Sciences Faculty of Science University of Ngaoundéré Ngaoundéré Cameroon department of Mining Oil Gas and Water Resources Faculty of Mining and Petroleum Industries University of Maroua Kaélé Cameroon department of Earth Sciences Faculty of Science University of Yaoundé I Yaoundé Cameroon

The purpose of this work is to characterize the sediments of the Babouri-Figuil Basin from a diagenetic point of view, the protolith context and weathering conditions, using major element geochemistry and mineralogy of the sedimentary rocks. Microscopic observations of diagenetic phenomena (on and around detrital grains of the basin), and the study of precipitation of the cement show that these sediments have undergone phenomena of compaction, dissolution, recrystallization and cementation. Cementation of quartz by silica is controlled by the rate of precipitation of silica, which is closely related to temperature than pressure. Thus, the sediments of the basin could be influenced by hydrothermalism during diagenesis, which would have inhibited their reservoir quality by generalized cementation phenomena. Geochemical features of the sediments show high contents in SiO2 (47.49 wt% - 90.79 wt%), Al2O3 (2.92 wt% - 23.18 wtdana;">%

关键词： diagenesis Geochemistry Cretaceous Sediments Babouri-Figuil Basin Sedimentary Basin

Mobility of Major and Trace Elements during the Bauxitization Processes in Ngaoundal Area (Adamawa Cameroon): Implication on Mining Perspectives

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Open Journal of Geology 2024年第1期14卷 81-100页

作者： André Sini Harouna Boukari ondoa augustin désiré balla djetenbe Beral Salomon Wangmené Awé Simon djakba Basga Jean Pierre Nguetnkam department of Mining Engineering School of Geology and Mining Engineering University of Ngaoundere Ngaoundere Cameroon department of Mining Engineering and Environment School of Mining Industry and Geology University of Abdou-Moumouni Niamey Niger department of Earth Sciences Faculty of Science University of Ngaoundere Ngaoundere Cameroon department of Mining Engineering Saint Jerome Polytechnic Saint Jerome Catholic University Institute of Douala Douala Cameroon Institute of Agricultural Research for development (IRAd) Garoua Cameroon

This study was focused to assess major and trace elements in bauxitic duricrusts from Ngaoundal and its surroundings in order to establish their mining interest. To this end, fieldworks, mineralogical and geochemical analyses were carried out. Four facies of duricrust were identified and characterized from the summit to the top of the slope of the Ngaoundal mountain: scoriaceous, pisolitic, nodular and massive. Mineralogical and geochemical analyses performed on 16 samples, revealed a significant concentration of Al2O3 mainly in the scoriaceous facies (over 45% in grade), moderate in Fe2O3 (averaging 23.69%) and SiO2 (averaging 21.7%). Trace elements were generally low, excluding Cr (421 ppm on average), Zr (327 ppm on average and V (213 ppm on average). In addition, the limited quantities of alkalis (Na2O, K2O) and alkaline earths metals (MgO, CaO) coupled with the very high values of Chemical Index of Alteration (CIA) and Mineralogical Index of Alteration (MIA), (more than 99%) attest to the intense weathering of the studied materials. Allitization and monosiallitization constituted the crystallochemical phenomena that have led to the development of bauxitic minerals. More than 90% of gibbsite in scoriaceous facies, 52.21% - 76.01% of kaolinite in pisolitic facies and more than 40% of hematite in nodular facies were quantified. The relationships between the constitutive components indicated their interdependency during the bauxitization phenomenon. The mineralogical and geochemical properties highlighted the mining interest of the studied duricrusts to be valorized.

关键词： duricrust Bauxitization Phenomenon Mineralogical and Geochemical Characterization Major and Trace Elements Mining Potential

diagenetic and Geochemical Study of Sediments from the Cretaceous Basin of Babouri-Figuil (North-Cameroon)

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Mobility of Major and Trace Elements during the Bauxitization Processes in Ngaoundal Area (Adamawa Cameroon): Implication on Mining Perspectives

International Journal of Geosciences（地球科学国际期刊） 2021年第4期

作者： augustin désiré balla ondoa Alexis Nyangono Abolo Léopold Ekengele Nga Appolinaire Tograne Simon Ngos III Elvine Paternie Edjengte doumo Armel Zacharie Ekoa Bessa

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The Mamfe Basin in the southern Benue trough extension between Cameroon and Nigeria:Gem origin and problem of lithostratigraphic nomenclature and marine transgression

Open Journal of Geology（地质学期刊） 2024年第1期

作者： André Sini Harouna Boukari ondoa augustin désiré balla djetenbe Beral Salomon Wangmené Awé Simon djakba Basga Jean Pierre Nguetnkam

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Acta Geochimica 2023年第3期42卷 495-516页

作者： Milan Stafford Tchouatcha Primus Tamfuh Azinwi Christel Sobdjou Kemteu augustin desire balla ondoa Leopold darlus Ngantchu Basil Azeh Anong Courage Gabvourta department of Earth Sciences Faculty of ScienceUniversity of DschangP.O.Box 67DschangCameroon department of Soil Science Faculty of Agronomy and Agricultural SciencesUniversity of DschangP.O.Box 222DschangCameroon department of Mining and Mineral Engineering National Higher Polytechnic InstituteUniversity of BamendaP.O.Box 39BambiliCameroon department of Earth Sciences Faculty of ScienceUniversity of YaoundeIP.O.Box 812Yaounde´Cameroon department of Earth Sciences Faculty of ScienceUniversity of NgaoundereP.O.Box 454NgaoundereCameroun

The Mamfe Basin has been the subject of many studies,but some debates persist,especially concerning the stratigraphic nomenclature,corundum origin,and marine *** aims of this work are(1)to propose a new lithostratigraphic nomenclature of the Mamfe Basin formation based on new field observations,(2)to determine the source rock distribution and the origin of gem deposits and(3)to correlate the Cameroon section of the Mamfe Basin with the Nigerian *** main results show that the name Manyu River Group is more appropriate as the Manyu River crosses all the facies in the Mamfe sedimentary Basin belonging to the Manyu *** to the facies analysis,the age of deposition,the mineralogic and geochemical data such as the V ***2O3andΣREE ***_(2)O_(3),TiO_(2)MgO,Na_(2)O,P_(2)O_(5),and CaO diagrams,this Group is composed of at least five Formations,including four Cretaceous Formations,from bottom to top:the Etoko Formation(alluvial and fluvial channel to fluvio-lacustrine deposits),the Nfaitok Formation(lagoonal deposits),the Bachuo Ntai Formation(fluvial braided channels or fluvio-deltaic environment)and the Eyumojock/NsanaragatiFormation(fluvio-lacustrine deposits)and the new Cenozoic Formation named Bakebe Formation(fluvio-lacustrine deposits).The gem minerals such as corundum,rutile,or tourmaline in the Cretaceous deposits of the Mamfe Basin are mainly detrital as indicated by the presence of worn shapes and fragments of these *** presence of sapphire in the AlboCenomanian deposits indicates a Precambrian age of the felsic source rock,likely the plutonic rocks such as granite or pegmatite as indicated by the abundance of tourmaline and high LREE/HREE ratios(14.81–34.29)and slightly negative and positive Eu anomalies(0.85–1.15).This marine incursion in the Mamfe Basin was probably from West Nigeria,according to the geographic location of the Mamfe Basin and the general palaeogeographic evolution of the Benue Trough.

关键词： Lithostratigraphy Marine transgression Heavy minerals Sapphires Mamfe Basin Benue Trough

Lithostructural controls in douala-Buea Region landscape (SW Cameroon margin):Insights from morphometric analysis

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Journal of Mountain Science 2021年第1期18卷 68-87页

作者： Christian balla ATEBA Sébastien OWONA Moussa NSANGOU NGAPNA Véronique MANGA TSIMI dieudonnéMINYEM Joseph MVONdO ondoa department of Earth Sciences Faculty of Sciencethe University of DoualaDouala 24157Cameroon department of Earth Sciences Faculty of Sciencethe University of Yaounde IYaounde 812Cameroon department of Mines and Quarries Faculty of Mining and Petroleum Industriesthe University of MarouaMaroua 814Cameroon

The douala-Buea Region(dBR;4°-5°N,9°-10°30’E),a portion of the southern Cameroon passive margin,developed on the Proterozoic granito-gneissic basement and the Cretaceous to Recent volcanosedimentary cover,was explored in order to evaluate the lithology and tectonics controls on its landscape usingthequalitativeandquantitative geomorphological analyses based on 30 m resolution digital Elevation Models(dEM)and field *** area displays an uneven and complex landscape differentiated into four morphological units:douala,Nkondjock,Kumba and Buea *** douala Unit corresponds to the Coastal Plain and is extended on the douala-Kribi/*** Nkondjock Unit represents a middle plateau developed on a Proterozoic granito-gneissic *** Kumba Unit matches with the southernmost volcanic Western Cameroon High *** Buea Unit corresponds to the Mount Cameroon *** relief analysis through mountain-front sinuosity(Smf,1.19–1.43)and relative relief ratio(Rr,0.10–2.31)vary from one unit to *** drainage network analysis including drainage patterns,stepped longitudinalriverprofiles,theassociated morphometric indexes,notably the concavity index(IC,0.56–0.88),deviation(d,267–2912 m),basin asymmetry factor(A_(F),6.37–42.12),hypsometric integral(HI,0.10–0.29),valley floor width to valley height ratio(V_(f),0.36–2.75),elongation ratio(R_(e),0.30–0.50),watershed slope(S,6.88–88.88)and stream length gradient index(SL,0–3332)vary from one basin to another *** results also show the heterogeneous and uneven dBR landscape controlled by its lithology and active *** drainage system reveals concave to concavo-convex longitudinal river profile shapes with knick points,asymmetric basins,and fault reactivations,and highlights the tectonics activity that used to occur through the time and their control on the ***,they document the lithostructural controls on the dBR landscape evolution,extendable in the whole

关键词： Morphometric indices Lithological control Structural control Morphological units douala-Buea Region SW Cameroon margin

Geochemical characterization of the metasedimentary rocks of the Yaounde Group within the southernmost North Equatorial tectonic belt:insights into geodynamic evolution

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Acta Geochimica 2023年第6期42卷 1017-1034页

作者： Simon Pierre Mbola Ndzana Moise Christian balla Ateba Germain Marie Monespérance Mboudou Moussa Nsangou Ngapna Jean Paul Sep Nlongang Solange Ipan Moise Bessong Jean Bosco Olinga Joseph Mvondo ondoa Sébastien Owona Paul Bilong department of Earth Sciences Faculty of ScienceUniversity of YaoundéIP.O.Box:812Yaounde´Cameroon Institute for Geological and Mining Research P.O.Box:4110NlongkakYaounde´Cameroon department of Earth Sciences Faculty of ScienceUniversity of DoualaP.O.Box:24157DoualaCameroon department of Geology Faculty of ScienceThe University of BueaP.O.Box:67BueaCameroon

The Proterozoic metasedimentary rocks of the Yaounde Group on the northern edge of the Congo Shield in Central Africa were investigated to understand their provenance and depositional ***,geochemistry,and field evidence helped to subdivide the metasediments into paragneiss,mica schist,chlorite schist,and quartzite which were derived from greywacke,shale,quartz arenite,litharenite *** are immature with some mature samples,moderately weathered and reworked Neo-and Post-Archean *** earth element signatures(Chondrite Eu/Eu^(*)≤1),enrichment of light rare earth elements over the heavy ones,and the La/Sc ratio(>0.7)are compatible with those of the intermediate and felsic sources from the upper continental *** metasediments were deposited in the continental arc setting and have evolved during Proterozoic times according to the Wilson cycle to form the West Gondwana including NE Brazil.

关键词： West Gondwana North Equatorial orogenic belt Yaounde Group Neoproterozoic basin Geochemistry of metasedimentary rocks Geodynamic evolution

Geochemical Characterization and Mineralogy of Babouri-Figuil Oil Shale,North-Cameroon

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Journal of Surface Engineered Materials and Advanced Technology 2014年第6期4卷 359-368页

作者： Alexis Jacob Nyangono Abolo Simon Ngos III augustin desire balla ondoa Bruno Garcia Maria Fernanda-Sarmiento Olive Cecile Mbesse Guy Martin Abolo daniel Mackaire Eloung Nna augustin Ephraim Nkengfack Emmanuel Ndjeng Jialin Qian Faculty of Sciences University of Yaounde IYaoundeCameroon Faculty of Sciences University of MarouaMarouaCameroon Faculty of Sciences University of NgaoundereNgaoundereCameroon Geosciences division Institut Francais du PetroleEnergies Nouvelles(IFPEN)Rueil-MalmaisonFrance Faculty of Sciences University of DoualaDoualaCameroon National Hydrocarbons Corporation YaoundeCameroon department of Chemistry China University of PetroleumBeijingChina

Organic geochemistry methods such as high temperature combustion, Rock-Eval pyrolysis and gas analysis were used to analyze oil shale from Babouri-Figuil Basin. Results show that the average content of organic matter is 36.25 %wt, while that of mineral matter is 63.75 %wt. The total organic carbon (TOC) is between 15.93 %wt and 26.82 %wt. The HI vs. Tmax diagram indicates an immature Type I kerogen. The average value of the oil potential (S2b) is 149.95 mg HC/g rock. The gases obtained by retort process are H2, CO2, CO and CnH2n, CnH2n+2. Finally, it emerges that, the organic matter of Babouri-Figuil shales was immature or has just reached the beginning of the oil window. The mineralogical study of Babouri-Figuil oil shale has been carried out by means of XRd (X-Ray diffractometry) and XRF (X-Ray Fluorescence spectrometry). The results show that mineral matrix contains silica, carbonates, sulphates, oxides and clay minerals. Besides, compounds contain metals and metalloids like Fe, In, Ca. The main oxides are SiO2 (majority), CaO, Fe2O3, Al2O3, SO3, and K2O.

关键词： Oil Shale Babouri-Figuil Organic Matter Mineral Matter Rock-Eval Pyrolysis X-Ray diffractometry X-Ray Fluorescence Spectrometry