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Geological Exploration of Marble Deposits in Toto Area, Nasarawa State, Nigeria

Natural Resources 2016年第2期7卷 83-92页

作者： ali moumouni Nathaniel Goeter Goki Mohammed Suleiman Chaanda Université Dandicko Dankoulodo de Maradi Maradi Niger Nasarawa State University Keffi Nigeria School of Geography Earth and Environmental Sciences University of Plymouth Plymouth UK

Geological mapping as well as chemical analysis for marble deposit in the Muro-Obugu-Panda area of Toto Local Government, Nasarawa State, Nigeria, was carried out. The objectives of the study are to first map out the extent of the deposit and then evaluate its chemical characteristics. The geology of the area forms part of the Upper Proterozoic low-grade (green schist facies) schist belts of Central Nigeria, and consists of schists, banded iron, quartzite, and marble. Geological mapping revealed that the marble deposit stretches in a NE-SW direction, from Muro in the north to Kolo in the south, covering about 28 km2. This deposit consists mainly of silicified gray and white varieties of marble. The mapping also identified three (3) exploration targets A—Panda, B—Obugu, and C— Soka. Chemical analysis of eight (8) selected samples shows that CaO content varies from 3.72 to 53.12 wt%. Other impurities are Fe2O3, Al2O3, MgO and SiO2. Plot of Na2O + K2O vs. SiO2 shows a positive correlation while that of CaO and MgO exhibits a well defined negative correlation with SiO2 and this reflects the introduction of chert during the deposition of the parent limestone of the marble body. The variation plot of CaO vs. MgO shows an inverse relationship. This is reflected in the inverse relationship in the proportion of calcite to dolomite in the marble. All these results correlate with those found in the adjacent area by previous workers and this indicates the same extension of marble in these areas. The Muro marble can be used economically as raw materials for a variety of products such as fillers, glass, papers, lime, pesticide and sewage treatment, decorative construction, monuments, paint making and most of all very suitable for cement production.

关键词： Marble Muro Obugu Panda-Toto Geochemistry

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Geochemistry and Mineralogy of the Upper Cretaceous-Paleocene Marine Series, Iullemmeden Basin, Niger Republic

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Journal of Geoscience and Environment Protection 2019年第12期7卷 1-19页

作者： moumouni ali Ibrahim Wagani Mohammed S. Chaanda Département de Géologie Faculté des Sciences et Techniques Université Dan Dicko Dankoulodo Maradi Niger Republic School of Geography Earth & Environmental Sciences University of Plymouth Drake Circus UK

Major and trace elements, mineralogy as well as the total organic content of the Upper Cretaceous-Paleocene Marine Series of the Iullemmeden basin in Niger were determined in order to assess their composition, the chemistry of the paleoenvironment and the nature of the parent crystalline rocks that they evolved from. The major and trace elements were analyzed using a Bruker Tracer IV energy-dispersive hand held X-ray fluorescence spectrometer, the mineralogical analyses were done using a Bruker AXS D8 Discover, while the total organic carbon was calculated by subtraction of inorganic carbon from the total carbon, determined using a CM5014 coulometer (UIC, Joliet, IL, USA) and a LECO SC-144DR instrument. Geochemical indices calculated from major oxides such as CIA, PIA, ICV and CIW have been computed and the results show that the Marine Series are made essentially of clay minerals of the smectite group (montmorillonite), quartz and other accessory minerals like rutile and calcite. Computed ratios of some trace elements such as V/(V + Ni) and V/(V + Cr) showed that the paleoenvironment was dysoxic-oxic and the low values (<2) of the Total Organic Carbon found in the sediments are justified by those poor preservative conditions. Based on Al2O3/TiO2 ratios, the sediments were derived from intermediate to acidic igneous rocks surrounding the basin.

关键词： Geochemistry and Mineralogy

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A Review of Nigerian Metallic Minerals for Technological Development

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Natural Resources 2011年第2期2卷 87-91页

作者： Umar Saidu Bamalli ali moumouni Mohammed Suleiman Chaanda 不详

The metallic mineral resources of Nigeria have not been fully appraised due to lack of sufficient studies and technology. Previous works identified a number of minerals deposits which have remained largely unevaluated. Some known deposits were confirmed while new ones were identified and documented. The metallic minerals found in Nigeria include iron ore (with over 3 billion metric tonnes), ferro-alloy minerals (Manganese, vanadium, nickel, chromite, columbite, molybdenum, zircon, wolfram/tungsten tourmaline and tantalite), tin ore (cassiterite), lead/zinc, niobium, uranium ore and precious metal (Gold). Looking at the diversity of the mineral types and industrial importance of most of them and the need to exploit and process the minerals for technological development, there is need to build up capability to produce efficient unit operations of the required sizes by indigenous manufacturers.

关键词： Metallic Minerals Technology Nigeria

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Socio-Spatial Dynamics of Land in Southwest Niger: The Case of the Commune of Gothèye

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Open Journal of Ecology 2024年第9期14卷 673-682页

作者： Maimouna ali Salamatou Abdourahamane Abdourhimou Amadou Issoufou Idrissa Soumana Mahamane ali Dpartement de Biodiversit et Productions Vgtales Facult des Sciences Agronomiques Universit de Diffa Diffa Niger Dpartement de Productions Animales Institut National de la Recherche Agronomique du Niger Niamey Niger Dpartement de Biologie Facult des Sciences et Techniques Universit Abdou Moumouni de Niamey Niamey Niger

In south-west Niger, ecosystems are losing several hectares of their surface area every year due to internally displaced persons and refugees. The commune of Gothèye is not immune to this situation. The aim of this research is to assess the impact of displaced persons and refugees on socio-spatio-temporal dynamics of ecosystems using Landsat images. To achieve this, Landsat TM, Landsat ETM+ and OLI 8 satellite images from September and March were used (2010 to 2024). Operations on Envi 5.3, field validation output and finally mapping on ArcGIS were the steps involved. Discrimination is significant, with kappa coefficients of 0.97, 0.96, 0.86 and 0.85. The results obtained indicate a degradation of natural ecosystems, reflected in a change in landscape structure, with a marked reduction in the quantity and quality of ecosystem goods. Analysis of the evolution of land use showed that 31% of the land remained in its initial state (unchanged), 69% underwent modifications, and 11% was converted to cropland. Over these fourteen years, the study area has undergone changes in land use patterns, which have resulted in a modification of landscape structure, with a marked decline in the quantity and quality of ecosystem services.

关键词： Dynamics Ecosystem Anthropization Remote Sensing Displaced Persons

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Reversible Semi-Fragile Watermarking Technique for Integrity Control of Relational Database

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Engineering（科研） 2024年第9期16卷 309-323页

作者： ali Hamadou Abdoul Aziz Issaka Hassane Lanciné Camara Harouna Naroua Department of Mathematics Dan Dicko Dankoulodo University of Maradi Maradi Niger Social Science and Management University of Bamako Bamako Mali Department of Mathematics and Computer Science Abdou Moumouni University Niamey Niger

Reversible watermarking schemes for relational database are usually classified into two groups: robust schemes and fragile schemes. The main limitation of existing reversible fragile methods is that they cannot differentiate between legal and malicious modifications. In this paper, we introduce a novel lossless semi-fragile scheme based on prediction-error expansion for content protection of relational database. In the proposed method, all attributes in a database relation are first classified according to their sensitivity to legitimate updates. Then, the watermark is embedded by expanding the prediction error of the two least significant digits of securely selected attributes. At watermark extraction, the proposed method has the ability to fully restore the original data while detecting and localizing tampering. The applicability of our method is demonstrated theoretically and experimentally.

关键词： Semi-Fragile Watermarking Integrity Control Reversibility Prediction-Error Expansion

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Trends of Land Use and Land Cover Change in the Savannah Ecological of the Protected Area Reserve Partielle de Dosso, Niger

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Natural Resources 2024年第3期15卷 61-68页

作者： Amadou Issoufou Abdourhimou Moussa Boubacar Habou Rabiou Soumana Idrissa Mahamane ali Faculté des Sciences Agronomiques Université de Diffa Diffa Niger Institut National de la Recherche Agronomique du Niger Niamey Niger Faculté des Sciences et Techniques Université Abdou Moumouni de Niamey Niamey Niger

Information on the dynamics of savannah is important to a country's plan to overcome the problems of uncontrolled development and environmental hazards. Taking the reserve partielle de Dosso, Niger as the case study area, this paper analyzed the long-term land use land cover change from 2002 to 2022. Satellite images were processed by using Google Earth Engine (GEE). Therefore, four major land cover classes were identified based on spectral characteristics of Land sat, namely, built-up, vegetation, cropland, bare land and water. The result revealed that barren and built-up areas increased at the expense of vegetation and water. From the four major land use land cover the large area is covered by vegetation which comprises about 192963.5 hectares followed by cropland and water consisting of 32506.43 and 1596.4 hectares respectively. The built-up area gained substantial area (most) during the study period. The reduction in some of the land cover/uses underlines the dangerous trend of the pressure poised by population growth and the changing functionality. Land cover change is influenced by a variety of societal factors operating on several spatial and temporal levels. The area estimates and spatial distributions of the LULC classes produced from the current study will assist local authorities, managers, and other stakeholders in decision-making and planning regarding forest land cover and uses.

关键词： Land Use/Cover Change Detection Classification Dosso

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Spatio-Temporal Dynamics of Land Use Units in the Kadzel Sub-Catchment Basin in Diffa, Niger

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Journal of Geographic Information System 2024年第4期16卷 259-275页

作者： Karema Ary Madou Kaoulé Moussa Mamoudou Boubacar Amadou Issoufou Abdorhimou Mahamane ali Faculty of Agronomic Sciences University of Diffa Diffa Niger Faculty of Science and Technology Abdou Moumouni University of Niamey Niamey Niger

Environmental degradation linked to land occupation and use, such as climate change and anthropogenic activities, has led to the modification of the landscape units of the Kadzel sub-watershed. The objective of this study is to analyze the dynamics of land use units in the Kadzel area in Diffa between 1992 and 2022 and to propose a future scenario for sustainable environmental management. The approach used relies on remote sensing and geographic information systems to analyze the dynamics of land use units. Additionally, the Markov Cellular Automata (CA) model was used to predict future land use. The land cover maps were produced from a supervised classification by maximum likelihood based on the true and false color compositions of bands 4/3/2 (TM5), 3/2/1 (ETM+) and 7/5/4 (8 OLI). Ten occupation classes were discriminated. Between 1992 and 2022, there was a decrease in the areas of irrigated crops (4.91% and 2.88%), of shrubby tree steppes (14.31% and 9.48%), field-fallow complexes (22.23% and 10.52%), and degraded areas. Grassy steppes (25.76% and 13.32%). However, this reduction has been beneficial for wastelands, urban areas and bodies of water. Based on predictive modeling, it is predicted that by 2052, urban areas, fallow field complexes and bare soils will constitute the main types of housing units. The regressive trend in natural resources appears to continue into the future with current land use practices.

关键词： Occupation Dynamics Environmental Problems Population Growth Lake Chad and Kadzel Basin

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Hydrogeophysical and Structural Investigations Using VES: A Case Study of Dosso Region in the Southwestern Part of the Meso-Cenozoic Iullemmeden Basin (Southwestern Niger)

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Open Journal of Geology 2024年第1期14卷 50-80页

作者： Abdou ali Ibrahim Huguette C. Emvoutou Alain Zanga Konaté Moussa Serigne Faye Department of Life and Earth Sciences Ecole Normale Supérieure Université Abdou Moumouni Niamey Niger Department of Earth Sciences Faculty of Sciences University of Douala Douala Cameroon Department of Geology Faculty of Sciences and Techniques University Cheikh Anta Diop of Dakar Dakar Senegal Department of Geology Faculty of Sciences and Techniques Université Abdou Moumouni Niamey Niger

A regional study connecting geolelectrical surveys with geology and hydrogeology was carried out in the western part of the Iullemmeden basin, precisely in the Dosso region in Niger. One hundred and four (104) vertical electrical sounds have been realized, among them nineteen representative were thus be used as parametric surveys. The local resistivity values of the geological formations of Quaternary range from 100 Ω⋅m to 1000 Ω⋅m (sands and lateritic sandstones). The Oligo-Miocene formation of the Continental terminal (Ct) shows resistivity values ranging from 1 to 5 Ω⋅m (brackish groundwaters) to 1500 Ω⋅m (clay sandstones) while the Upper Cretaceous formation of the Continental “hamadien” (Ch) indicates values ranging from 20 Ω⋅m (sandy clay) to 5000 Ω⋅m (clayey sandstones). The geological formations of Paleocene have values from 2 Ω⋅m (marls) to 60 Ω⋅m (calcareous marl), while the Precambrian basement exhibits values of granite around 300 Ω⋅m to 60,000 Ω⋅m. The update of the structural settings reveals many faults in the study area which explain both the shape of the basin and the geometry of the aquifers. Tectonics is also consistent with the hydraulic characteristics of aquifers. In addition, brackish groundwaters were identified as perched aquifer groundwaters in different depths in Dosso region. They probably come from the marine brines during the regression of the Paleocene Sea.

关键词： Vertical Electrical Soundings Continental Terminal Continental “Hamadien” Brackish Groundwaters Iullemmeden Basin Dosso Region

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Application of Machine Learning Methods on Climate Data and Commercial Microwave Link Attenuations for Estimating Meteorological Visibility in Dusty Condition

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Engineering（科研） 2022年第2期14卷 85-93页

作者： Wend Yam Serge Boris Ouedraogo Sibiri Tiemounou moumouni Djibo ali Doumounia Serge Roland Sanou moumouni Sawadogo Idrissa Guira François Zougmore Laboratoire Matériaux et Environnement Université Joseph KI-ZERBO Ouagadougou Burkina Faso Institut du Génie Informatique et Télécommunications Ecole Polytechnique de Ouagadougou Ouagadougou Burkina Faso Ecole Normale Supérieure Koudougou Burkina Faso Autorité de Régulation des Communications électroniques et des Postes Ouagadougou Burkina Faso Telecel Faso SA Ouagadougou Burkina Faso

Accurately measuring meteorological visibility is an important factor in road, sea, rail, and air transportation safety, especially under visibility-reducing weather events. This paper deals with the application of Machine Learning methods to estimate meteorological visibility in dusty conditions, from the power levels of commercial microwave links and weather data including temperature, dew point, wind speed, wind direction, and atmospheric pressure. Three well-known Machine Learning methods are investigated: Decision Trees, Random Forest, and Support Vector Machines. The correlation coefficient and the mean square error, between the visibility distances estimated by Machine Learning methods and those provided by Burkina Faso weather services are computed. Except for the SVM method, all the other methods give a correlation coefficient greater than 0.90. The Random Forest method presents the best result both in terms of correlation coefficient (0.97) and means square error (0.60). For this last method, the best variables that explain the model are selected by evaluating the weight of each variable in the model. The best performance is obtained by considering the attenuation of the microwave signal and the dew point.

关键词： Meteorological Visibility Commercial Microwave Link Machine Learning Climate Parameters Dust Attenuation

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Neonatal Seizures: Epidemiological, Diagnostic Aspects and Short-Term Outcome at Issaka Gazoby Maternity Hospital of Niamey, Niger

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Open Journal of Pediatrics 2023年第5期13卷 689-696页

作者： Samaila Aboubacar Kamaye moumouni Garba moumouni Mamoudou Abdou Djafar Dan Jari Salissou Yahaya Haoua Gagara Adama ali Hamani Amina Toudou Daouda Moussa Hassane Djibo Fatimata Soumana alido Service de Pédiatrie H&#244pital National Amirou Boubacar Diallo Niamey Niger Faculté des Sciences de la Santé Université Abdou Moumouni de Niamey Niamey Niger Maternité Issaka Gazoby de Niamey Niamey Niger Service de Neurologie Medicale H&#244pital National de Niamey Niamey Niger

Introduction: Neonatal seizures are one of the most challenging situations for paediatricians. The objective of this work was to study the epidemiological and diagnostic aspects and short-term outcomes of neonatal seizures at Issaka Gazoby Maternity Hospital in Niamey. Patients and Methods: This was a prospective study from November 2020 to April 2021 in the neonatology department of Issaka Gazoby Maternity Hospital. All newborns aged 0 to 28 days hospitalized for seizures and/or having convulsions during hospitalization were included. Neonatal characteristics, diagnostic aspects, and their outcomes were studied. Data were analyzed using SPSS version 20 software. Results: Of the 3.068 newborns admitted, 69 cases of neonatal seizures were recorded (2.24%). The sex ratio was 1.22, and 94.2% of neonates were born at term. Generalized crises were found in 50.7%. The main etiologies were perinatal asphyxia (46.4%) and early-onset neonatal infection (40.6%). The death rate was 20.3%. Neonates died between one (1) and three (3) days of age in 42.9%. The main death causes were perinatal asphyxia (50%) and early-onset neonatal infection (21.4%). Conclusion: Neonatal seizures are uncommon frequent, with a semiology dominated by generalized seizures. Mortality is high. The reinforcement of preventive measures is necessary.

关键词： Seizures Neonatal Perinatal Asphyxia Niger

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