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Integrating geochemical(surface waters, stream sediments)and biological(diatoms) approaches to assess AMD environmental impact in a pyritic mining area： Aljustrel(Alentejo, Portugal)

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Journal of Environmental Sciences 2016年第4期28卷 215-226页

作者： Ana Teresa Luís Nuno Duraes SaloméFernandes Pinheiro de Almeida Eduardo Ferreira da Silva University of Aveiro Department of GeosciencesGeoBioTec--GeobiosciencesGeotechnologies and Geoengineering Research CenterCampus de Santiago3810-193 AveiroPortugal University of Aveiro Department of BiologyGeoBioTec--GeobiosciencesGeotechnologies and Geoengineering Research CenterCampus de Santiago3810-193 AveiroPortugal Centro de Ciencias do Mar CCMARUniversidade do AlgarveCampus de Gambelas8005-139 FaroPortugal

Aljustrel mines were classified as having high environmental hazard due to their large tailings volume and high metal concentrations in waters and *** assess acid mine drainage impacted systems whose environmental conditions change quickly,the use of biological indicators with short generation time such as diatoms is *** study combined geochemical and diatom data,whose results were highlighted in 3 groups：Group 1,with low p H（1.9–5.1）and high metal/metalloid（Al,As,Cd,Co,Cu,Fe,Mn,Ni,Pb,Zn;0.65–1032 mg/L）and SO4（405–39124 mg/L）*** acidophilic species,Pinnularia aljustrelica,was perfectly adapted to the adverse conditions;in contrast,teratological forms of Eunotia exigua were found,showing that metal toxicity affected this *** low availability of metals/metalloids in sediments of this group indicates that metals/metalloids of the exchangeable fractions had been solubilized,which in fact enables metal/metalloid diatom uptake and consequently the occurrence of teratologies;Group 2,with sites of near neutral p H（5.0–6.8）and intermediate metal/metalloid（0.002–6 mg/L）and SO4（302–2179 mg/L）concentrations;this enabled the existence of typical species of uncontaminated streams（Brachysira neglectissima,Achnanthidium minutissimum）;Group 3,with samples from unimpacted sites,showing low metal/metalloid（0–0.8 mg/L）and SO4（10–315 mg/L）concentrations,high pH（7.0–8.4）and Cl contents（10–2119 mg/L）and the presence of brackish to marine species（Entomoneis paludosa）.For similar conditions of acidity,differences in diversity,abundance and teratologies of diatoms can be explained by the levels of metals/metalloids.

关键词： Surface waters stream sediments Diatoms Metals/metalloids AMD Teratologies

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Assessment of trace metals contamination in stream sediments and soils in Abuja leather mining, southwestern Nigeria

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Acta Geochimica 2018年第4期37卷 592-613页

作者： Abiola Oyebamiji Adegbola Odebunmi Hu Ruizhong Atta Rasool State Key Laboratory of Ore Deposit Geochemistry Instituteof Geochemistry Chinese Academy of SciencesGuiyang 550081 China Department of Geological Services Ogun State Ministry of Commerce and Industry Oke-Mosan Abeokuta Nigeria University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of SciencesGuiyang 550081 China Department of Science Laboratory Technology Ekiti StateUniversity Ado-Ekiti Ekiti State Nigeria

This study is aimed at determining the level of environmental degradation as well as the concentration of trace elements in soil and stream sediments in order to evaluate the environmental impact of the mining ***-five(25) soils and ten(10) stream sediment samples were collected from the study area. The physicochemical parameters were determined using appropriate instrumentation with the aid of a digital p H meter(Milwaukee meter) to measure the p H and electrical conductivity, total dissolved solids, moisture content and loss on ignition of the soil and stream sediment samples. The p H of the soil sample ranged from(6.10 to 7.19); Electrical conductivity ranged from(21.3 to 279.4 μS/cm), moisture content varied from(0.60% to 7.20%), and the LOI ranged from(2.03% to 18.62%). The results of the analysis showed that the concentrations of the trace elements in the soils and stream sediment samples were slightly higher than the background values. Plots of the trace elements in stream sediment samples show moderate, consistent decrease downstream except at points where there was mine water discharge into the main river. The pollution levels of heavy metals were examined in stream sediment and soil samples using different assessable indices, such as the enrichment factor, which showed significant-moderate enrichment for Cr, Th, Nb, Zn, Pb, Y and Zr and the geoaccumulation index, which showed practically moderate contamination with Cr, Ni and Sr based on regional background reference values. Geo-accumulation index and contamination index for soils and stream sediment revealed uncontaminated to moderate contamination. Likewise,elements with moderate contamination were Cr, Ni and *** Pearson correlation showed that there were significant positive associations among selected metals in soil and stream sediment samples.

关键词： Trace metals stream sediments Geo-accumulation index - PCA Soil Southwestern Nigeria

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Features of sampling stream sediments of large river valleys under cryolithogenesis conditions in the Balygychan-Sugoy trough,North-East of Russia

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Acta Geochimica 2024年第4期43卷 638-660页

作者： Artem S.Makshakov Raisa G.Kravtsova A.P.Vinogradov Institute of Geochemistry Siberian Branch of the Russian Academy of SciencesFavorskiy Str 1AIrkutskRussia 664033

Comprehensive research has been implemented to raise the efficiency of the geochemical survey of stream sediments(SSs)that formed under the cryolithogenesis *** authors analysed the composition,structure and specific features of the formation of exogenous anomalous geochemical fields(AGFs)identified through SSs of large river valleys of IV *** our case,these were the valleys of Maly Ken,Ken and Tap *** rivers are located in the central and southern parts of the Balygychan-Sugoy trough enclosed in the Magadan region,North-East of *** authors proposed a new technique to sample loose alluvium of SSs in the large river valleys along the *** profiles were located across the *** AGFs of Au,Ag,Pb,Zn,Sn,Bi,Mo and W were *** between elements have been *** elements are the main indicator elements of Au-Ag,Ag-Pb,Sn-Ag,Mo-W and Sn-W mineralization occurring on the sites under *** results obtained were compared with the results of geochemical surveys of *** is concluded that the AGFs recognized along the profiles reflect the composition and structure of eroded and drained ore zones,uncover completely and precisely the pattern of element distribution in loose sediments of large water *** alluvium fraction<0.25 mm seems to be most significant in a practical sense,as it concentrated numerous ore *** of this fraction in the river valleys of IV order does not cause any difficulty,for this kind of material is *** developed technique of alluvium sampling within large river valleys is efficient in searching for diverse mineralization at all stages of prognostic *** is applicable for geochemical survey of SSs performed at different scales both in the North-East of Russia,as well as other regions with similar climatic conditions,where the SSs are formed under the cryolithogenesis conditions.

关键词： stream sediments Large river valleys Geochemical fields Mineralization Indicator elements Geochemical survey

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Source, Contamination Assessment and Risk Evaluation of Heavy Metals in the stream sediments of Rivers around Olode Area SW, Nigeria

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Journal of Environmental & Earth Sciences 2023年第1期5卷 65-84页

作者： Stellamaris Isioma Okonkwo Sunday Ojochogwu Idakwo Mofolorunsho Samuel Kolawole Olufemi Faloye Anthony Azubuike Elueze Department of Geology Federal University of TechnologyOwerriOwerriImo State460114Nigeria Department of Geology and Mining Ibrahim Badamasi Babangida UniversityLapaiNiger State740005Nigeria Department of Geology Federal UniversityOye-EkitiEkiti State360001Nigeria Department of Geology University of IbadanIbadan200005Nigeria

In order to investigate the source,contamination,and risk of heavy metals such as Pb,Zn,Cu,Ni,Co,Fe,Mn,and Cr,twelve(12)stream sediments and ten(10)rock samples were collected from pegmatite mining sites at Olode and its environs inside Ibadan,Southwestern *** average values and order of abundance obtained followed the pattern:Mn(595.09)>Ba(80)>Cr(50.82)>V(45.09)>Zn(29.73)>Cu(13.82)>Co(13.82)>Sr(10.46)>Ni(9.73)>Pb(9.09)>Fe(1.59).These were greater than the background values,indicating that mining has a negative impact on the study area,as indicated by the high coefficient of variation and correlation values(>0.6)for Copper-Lead(0.929),Copper-Vanadium(0.970),Copper-Chromium(0.815),Lead-Vanadium(0.884),and *** the basis of the enrichment factor(EF),the Olode sediments show extremely high enrichment for Mn and Ba in the research *** and Ni are most likely to blame for the elevated contamination levels,according to CF *** degree of contamination(CD),pollution load index(PLI),pollution index(PI),and modified pollution index(MPI)all revealed high levels of contamination in all stream sediment samples,whereas Igeo shows that the Olode stream sediments are“practically uncontaminated to extremely contaminated by Ni,Co,and Mn”.Ni and Cu are the major regulating factors that are most likely causing the possible *** a result,these findings give important information for conducting appropriate ecological management research.

关键词： Olode Heavy metals stream sediments Risk assessment Contamination indices

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Spectroscopy Studies on stream sediments in the Terahertz Range

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Optics and Photonics Journal 2016年第8期6卷 145-149页

作者： Chen Chen Jinsong Liu Jianquan Yao Wuhan National Laboratory for Optoelectronics School of Optical and Electronic Information Huazhong University of Science and Technology Wuhan China School of Physics and Optoelectronic Engineering Yangtze University Institute of Photoelectric Technology Jingzhou China Institute of Laser and Opto-Electronics School of Precision Instrument and Optoelectronics Engineering Tianjin University Tianjin China

In order to study stream sediments in the terahertz range, we have measured six reference stream sediment samples by terahertz time-domain spectroscopy (THz-TDS). We obtained the absorption coefficients and refractive indexes. By analyzing the spectra, we got different drops in amplitude and delays in time. The absorption and refractive properties of samples changed with its components and types. In addition, we also found there was a nearly linear relationship between the absorption coefficient and the frequency. We calculated the slope value (K) of each sample by linear fitting, and find the K was corresponding to the contents of the samples. The results showed THz-TDS was an effective method to the analysis of stream sediments.

关键词： Terahertz Time-Domain Spectroscopy stream sediments Absorption Coefficient Refractive Index

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Heavy Metal Dispersion in stream sediments in River Iyiudene, Abakaliki South-Eastern Nigeria: Source, Distribution Pattern, and Contamination Assessment

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Journal of Geoscience and Environment Protection 2022年第7期10卷 48-69页

作者： Emmanuel U. Nwazue Erepamo J. Omietimi Eniye Mienye Osayamen J. Imarhiagbe Olumide A. Adeosun Paulinus N. Nnabo Department of Geology Ebonyi State University Abakaliki Nigeria Department of Geology University of Pretoria Pretoria South Africa Bayelsa state Polytechnic Aleibiri Ekeremor Nigeria Division of Earth Sciences and Geography RWTH Aachen University Aachen Germany Department of Geology University of Ibadan Ibadan Nigeria

River Iyiudene is a vital distributary resource in Abakaliki, southeastern Nigeria and conveys an abundant amount of sediments to provincial and residual ecosystems. Although the importance of the river cannot be overemphasized, the geochemistry of its stream sediments is less investigated. Twenty (20) stream sediment samples were taken at the centre of the river channels to represent the entire drainage area well and avoid collapsed bank materials. The stream sediment samples were used to determine the dispersion, contamination status and sources of heavy metal concentrations. Total elemental digestion accompanied this with the use of aqua regia, an admixture of Hydrochloric acid (HCl) and Nitric acid (HNO3) in the ratio of 3:1 using the atomic absorption spectrometer (AAS). The heavy metal concentration levels in River Iyiudene were low compared with sediments from Imo River, Gulf of California, Upper continental crust, Average shale and surface horizons, excluding Cd, which showed high concentration levels than the other reference studies. The results delineated a wide contrast in the concentration levels of the heavy metals, with the mean contents in the order Zn > Cu > Pb > Cd > Ni > As. The pollution evaluation utilizing the Effect range low (ERL), Effect range median (ERM), single pollution index, and geo-accumulation index revealed Cd contamination. This study indicates that the heavy metals were sourced from the natural geological background of the river basin and possibly from agricultural runoff and atmospheric pollutants.

关键词： Benue Trough Heavy Metals Contamination stream sediments Single Pollution Index Correlation Matrix

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Geochemical stream Sediment Survey in the Wadi Umm Rilan Area,South Eastern Desert,Egypt:A New Occurrence for Gold Mineralization

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Acta Geologica Sinica(English Edition) 2017年第3期91卷 1041-1062页

作者： Mohamed Abdallah Gad DARWISH Geology Department Faculty of ScienceAswan University

The present paper investigates the stream sediment geochemistry, behavior of gold and associated elements, delineates Au-anomalous sites and defines related sources in the Wadi Umm Rilan area. Fifty three major and trace elements were analyzed using ICP-MS and treated applying various statistical and mapping techniques. The results showed a significant difference of mean and median Au and most chemical elements in the three portions of the area, and higher values were recorded in the western portion. Furthermore, Au-anomalous sites appeared in upper and lower parts of the Wadi Umm Rilan, along the tributaries of metavolcanic unit and near granitoid contacts. This indicates the main source of Au mineralization is related to emplacement of granitoid plutons and accompanying hydrothermal solutions. There are significant indications for the presence of more than one mineralization event forming a probable single major episode of mineralization in the area, involving Au, Pb and U mineralizations. Geology, geomorphologic aspects and weathering processes could control stream sediment geochemistry, anomalies of Au and associated elements, elemental association and their dispersion patterns. Therefore, the area is fruitful and regarded as a promising target for Au exploration, using Ag, As, Sb, Cd, Cs, and TI as pathfinder elements.

关键词： geochemical survey stream sediments Au mineralization Wadi Umm Rilan area southEastern Desert Egypt

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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

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