scholarly journals Tellus regional stream water geochemistry: environmental and mineral exploration applications

2022 ◽  
Vol 22 (1) ◽  
pp. geochem2021-050
Author(s):  
Vincent Gallagher ◽  
Eric C. Grunsky ◽  
Mairéad M. Fitzsimons ◽  
Margaret A. Browne ◽  
Sophie Lilburn ◽  
...  
Keyword(s):  
Stream Water ◽  
Mineral Exploration ◽  
Principal Component ◽  
Water Hardness ◽  
Environmental Issues ◽  
Survey Area ◽  
Background Concentrations ◽  
Water Geochemistry ◽  
Content Type ◽  
Supplementary Material

Regional stream water geochemistry acquired as part of the Tellus programme in Ireland has been analysed to assess its potential for application to environmental assessment and mineral exploration. Interpolated geochemical maps and multivariate statistical analysis, including principal component analysis and random forest classification, demonstrate broad geogenic control of stream water chemistry, with both bedrock and subsoil contributing to the patterns observed. Surface water regulations set Environmental Quality Standard values for individual Priority Substances and Specific Pollutants that may depend on background concentrations and/or water hardness. The high resolution of Tellus stream water data and their location on low-order streams have allowed estimation of background concentrations and water hardness in the survey area, with significant implications for water monitoring programmes. Anthropogenic inputs to stream water in the survey area come mainly from agricultural sources and Tellus data suggest few catchments are unaffected. Comparison of Tellus stream water geochemistry with stream sediment and topsoil geochemistry suggest that stream water geochemistry has strong potential for use in mineral exploration, with the same base metal and gold pathfinder anomalies apparent in all three data sets. Cluster analysis indicates that base metals in stream water are associated with organic matter but statistical analysis may be employed to distinguish mineralization-related signatures.Supplementary material: Comparison of cation/anion associations using Piper plots and principal component analysis is available at https://doi.org/10.6084/m9.figshare.c.5683094Thematic collection: This article is part of the Hydrochemistry related to exploration and environmental issues collection available at: https://www.lyellcollection.org/cc/hydrochemistry-related-to-exploration-and-environmental-issues

scholarly journals Hydrogeochemistry of porphyry related solutes in ground and surface waters; an example from the Casino Cu-Au-Mo deposit, Yukon, Canada

2022 ◽  
pp. geochem2021-058
Author(s):  
J.A. Kidder ◽  
M.B. McClenaghan ◽  
M.I. Leybourne ◽  
M.W. McCurdy ◽  
P. Pelchat ◽  
...  
Keyword(s):  
Surface Waters ◽  
Stream Water ◽  
Mineral Exploration ◽  
Environmental Issues ◽  
Isotopic Data ◽  
Content Type ◽  
Hydrothermal Mineralization ◽  
Groundwater Samples ◽  
Supplementary Material ◽  
Ore Zones

The Casino Cu-Au-Mo deposit is one of the largest and highest-grade porphyries of its kind in Canada, residing in an unglaciated region of west central Yukon. A batch of 22 stream water samples and eight groundwater samples were collected proximal to the deposit for the purpose of identifying the most diagnostic trace element and isotopic pathfinders associated with the hydrothermal mineralization, as well as establishing natural hydrogeochemical baselines for the area. Water chemistry around this deposit was investigated because: (i) the deposit has not yet been disturbed by mining; (ii) the deposit was known to have metal-rich waters in local streams; and (iii) the deposit has atypically preserved ore zones. Surface and ground waters around the Casino deposit are anomalous with respect to Cd (up to 5.4 µg/L), Co (up to 64 µg/L), Cu (up to 1657 µg/L), Mo (up to 25 µg/L), As (up to 17 µg/L), Re (up to 0.7 µg/L), and Zn (up to 354 µg/L) concentrations. Sulfur and Sr isotopes are consistent with proximal waters interacting with the Casino rocks and mineralization; a sulfide-rich bedrock sample from the deposit has δ34S = -1.2 ‰ and proximal groundwaters are only slightly heavier (-0.3 to 3.1 ‰). These geochemical and isotopic results indicate interaction and dispersion of porphyry related solutes in ground and surface waters and point to suitability of hydrogeochemistry as a medium for mineral exploration for porphyry-style mineralization in the Yukon, and elsewhere in Canada.Supplementary material: The physicochemical, major, trace, and isotopic data of stream and groundwaters used in this manuscript is publicly available as an Open File Report (OF 8823) from the Geological Survey of Canada.Thematic collection: This article is part of the Hydrochemistry related to exploration and environmental issues collection available at: https://www.lyellcollection.org/cc/hydrochemistry-related-to-exploration-and-environmental-issues

Lead, zinc and arsenic contamination of pit lake waters in the Zeida abandoned mine (High Moulouya, Morocco)

2021 ◽  
pp. geochem2021-009
Author(s):  
Lamiae EL ALAOUI ◽  
Abdelilah Dekayir ◽  
Mohammed Rouai ◽  
EL Mehdi Benyassine
Keyword(s):  
Organic Matter ◽  
Iron Oxides ◽  
Environmental Issues ◽  
Abandoned Mine ◽  
Equal Proportion ◽  
Pit Lake ◽  
Content Type ◽  
Link Type ◽  
Supplementary Material ◽  
Lake Waters

In the Zeida abandoned mine, pit lake waters exhibit alkaline pH and high conductivity. The concentrations of the total dissolved lead and zinc are very low due to their adsorption on clay minerals and iron oxyhydroxides. Conversely, arsenic concentrations in two lakes (ZL1 and ZA) exceeded WHO water quality guidelines. The As content is relatively high in ZL1 lake and exists mainly as As(V). In ZA lake, As(III) occurs in low concentration compared to the total dissolved arsenic, while dimethylarsenic acid [H2AsO2(CH3)2, DMA) prevails. This means that arsenic was methylated by organic matter produced by microorganisms such as chlorella. The sequential extraction of floor sediments in two lakes shows that the bioavailable arsenic contents change between the two lakes. In ZA lake, the sediments show high concentrations of lead and arsenic compared to ZL1 sediment since it is surrounded by mining waste tailings, which are rich in such chemical elements. An arsenic leaching test of ZA sediment shows that bioavailable arsenic is distributed in equal proportion between clay/carbonates, sulfide-organic matter, and iron oxides (HFO) phases, while in ZL1, most of the arsenic is linked to hydrous iron oxides (HFO).Thematic collection: This article is part of the Hydrochemistry related to exploration and environmental issues collection available at: https://www.lyellcollection.org/cc/hydrochemistry-related-to-exploration-and-environmental-issuesSupplementary material:https://doi.org/10.6084/m9.figshare.c.5545316

Using analytic hierarchy process (AHP)-based index and geographic information system (GIS) in geochemical exploration of gold

2021 ◽  
pp. geochem2021-013
Author(s):  
Erkan Yılmazer ◽  
Murat Kavurmaci ◽  
Sercan Bozan
Keyword(s):  
Hierarchical Structure ◽  
Principal Component ◽  
Content Type ◽  
Distribution Maps ◽  
Rock Samples ◽  
High Sulfidation ◽  
The Hierarchical Structure ◽  
Supplementary Material ◽  
Comparison Of The Results ◽  
Hierarchy Process

In this study, a gold exploration index (GEI) that reduces financial expenditures and time losses during exploration studies has been developed using the Analytical Hierarchy Process (AHP) in a region where a high sulfidation epithermal Au deposit exists. The GEI can be used to predict the location of the target element by evaluating the maps obtained from related element distributions together with a GEI-based prediction map. The hierarchical structure of the index has been established based on geochemistry of the rock samples. The elements used in the design of the hierarchical structure are arsenic (As), silver (Ag), antimony (Sb), copper (Cu), manganese (Mn), lead (Pb) and zinc (Zn), which are determined by the correlation analysis and experts’ opinions. The efficiency scores of the alternatives were converted into prediction maps called GEI-based anomaly distribution maps. They were compared with the maps derived from both GIS-based overlay analysis of the rock samples and spatial gold distribution. The efficiency scores of the alternatives in these maps were categorized into three groups as "high,” "medium," and "weak" in terms of gold potential. Comparison of the results with those derived using Principal Component (PCA), Weighted Total (WS) and Weighted Product Models (WPM) methods showed that the produced index yields reliable information that can be used to determine where gold enrichment occurs, especially in high sulfidation epithermal environments.Supplementary material:https://doi.org/10.6084/m9.figshare.c.5443218

The response of calcareous nannoplankton to the latest Pliensbachian-early Toarcian environmental changes in the Camino section (Basque Cantabrian Basin, North Spain)

2021 ◽  
pp. SP514-2020-256
Author(s):  
Ángela Fraguas ◽  
Juan José Gómez ◽  
Antonio Goy ◽  
María José Comas-Rengifo
Keyword(s):  
Environmental Changes ◽  
Principal Component ◽  
Black Shales ◽  
Time Interval ◽  
Calcareous Nannofossils ◽  
Calcareous Nannofossil ◽  
Content Type ◽  
Lowermost Part ◽  
Supplementary Material ◽  
Basque Cantabrian Basin

AbstractQuantitative analysis performed on latest Pliensbachian-early Toarcian calcareous nannofossil assemblages from the Camino section (Basque Cantabrian Basin), allowed to decipher their response to the environmental changes recorded during this time interval, characterized by an extinction event. The results were introduced within a principal component analysis and compared to the stable isotope and total organic carbon curves. During the latest Pliensbachian, the Mirabile and the lowermost part of the Semicelatum Ammonite Subzones, Schizosphaerella, Bussonius prinsii, Biscutum finchii, Calcivascularis jansae and Similiscutum avitum, taxa that probably thrived in rather cold waters, dominated the calcareous nannofossil assemblages. Coinciding with the warmer and probably wetter conditions, which probably led to an increase in surface water fertility, recorded slightly below the extinction boundary, the mesotrophic taxa B. novum, L. hauffii and Calyculus spp. were dominant. Nevertheless, T. patulus and C. jansae, which became extinct just below the extinction boundary, show preferences for oligotrophic conditions. Salinities similar to those of modern oceans have been inferred around the extinction boundary, considering the coupling between the abundances of Calyculus spp. and the species richness, and the absence of black-shales. After the extinction boundary, nannofossil assemblages were dominated by the deep-dweller C. crassus and the shallow-dweller Lotharingius species, interpreted as opportunistic taxa. This work confirms that calcareous nannofossils are a useful tool for palaeoceanographic and palaeoenvironmental reconstructions, especially in terms of climatic changes.Supplementary material at https://doi.org/10.6084/m9.figshare.c.5481527

The waste rock of the Touro copper deposit in Galicia, Spain: challenges for its environmental characterization

2021 ◽  
pp. geochem2020-081
Author(s):  
Tom Meuzelaar ◽  
Pablo Núñez-Fernández ◽  
Agustín Martín-Izard ◽  
Daniel Arias-Prieto ◽  
Fernando Díaz-Riopa
Keyword(s):  
Sulfide Oxidation ◽  
Environmental Issues ◽  
Metamorphic Rocks ◽  
Acid Rock ◽  
Neutralization Potential ◽  
Content Type ◽  
Oxidation Rates ◽  
Ph Values ◽  
Link Type ◽  
Supplementary Material

Characterization of metamorphic rocks to evaluate waste material acid rock drainage potential is particularly challenging as commonly used laboratory methods can result in significant under-prediction of ARD potential. Static tests were conducted for over 300 samples from the Touro copper project and indicate that carbon-based methods frequently overestimate acid neutralization potential due to the presence of both graphite and manganese-iron carbonates. The Modified Sobek method more accurately accounts for the buffering capacity of carbonates and does not account for graphite, although aluminosilicate dissolution kinetics need to be evaluated in the context of sulfide oxidation rates. Historic sulfur assays for the project relied on methods insufficient to fully digest metamorphosed sulfides and required correction. The more aggressive Leco sulfur method provides accurate sulfur estimates and has been adopted for the project going forward.Static test metrics such as the Net Neutralization Potential or Neutralization Potential Ratio, therefore, can give misleading results when incorrect characterization methods are employed. Such metrics should be considered as screening level, used with caution, and complemented with careful field and laboratory kinetic tests. Preliminary humidity cell testing of five Touro samples suggests that terminal pH values for cells that have become acidic closely match predicted NAG pH values. The NAG pH test avoids some of the challenges associated with sulfur and carbon predictions in metamorphic rocks as it directly buffers sulfide oxidation acidity with available material neutralization potential. As such, NAG pH has been adopted as the accepted project metric for segregating acid-generating from non-acid-generating waste.Thematic collection: This article is part of the Hydrochemistry related to exploration and environmental issues collection available at: https://www.lyellcollection.org/cc/hydrochemistry-related-to-exploration-and-environmental-issuesSupplementary material:https://doi.org/10.6084/m9.figshare.c.5389948

Geochemistry of natural acid rock drainage in the Mt. Evans area, Anaconda-Pintler Range, Montana, USA

2021 ◽  
pp. geochem2021-068
Author(s):  
C. H. Gammons ◽  
M. F. Doolittle ◽  
K. A. Eastman ◽  
S. R. Poulson
Keyword(s):  
Acid Rock Drainage ◽  
Isotope Composition ◽  
Sulfide Oxidation ◽  
Environmental Issues ◽  
Acid Rock ◽  
Content Type ◽  
Link Type ◽  
Wilderness Area ◽  
Supplementary Material ◽  
Field Area

This paper investigates natural acid rock drainage in two streams draining either side of Mount Evans, Montana. Bedrock consists of pyrrhotite-bearing schist intruded by granitic dikes and plutons of late Cretaceous to Tertiary age. The headwaters of both streams are moderately acidic (pH < 5.0) and carry elevated loads of dissolved sulfate, aluminum, and other trace metals (Cd, Co, Cu, Mn, Zn) as well as rare earth elements (REE). Copious aluminum precipitates inferred to be hydrobasaluminite coat boulders of both streams as pH rises > 5, with adsorption of copper and REE. Concentrations and loads of dissolved sulfate and trace elements are anomalously high in a small tributary that is sourced by meltwater from a rock glacier. The S-isotope composition of dissolved sulfate in both watersheds is similar to that of pyrrhotite in the meta-sediments, but not molybdenite in late porphyry dikes. Calculations of sulfate flux (i.e., sulfate load divided by surface area) indicate a relatively fast rate of sulfide oxidation in the study area, possibly due to exposure of fresh bedrock in the steep and recently glaciated field area. Overall, the geochemistry of the site suggests the possible presence of a metamorphosed sedimentary-exhalative (SEDEX) deposit, a possibility that is unlikely to be tested by drilling given the proximity of the site to a federal wilderness area. Thematic collection: This article is part of the Hydrochemistry related to exploration and environmental issues collection available at: https://www.lyellcollection.org/cc/hydrochemistry-related-to-exploration-and-environmental-issuesSupplementary material:https://doi.org/10.6084/m9.figshare.c.5649850

Robust-PCA-based hierarchical plane extraction for application to geometric 3D indoor mapping

2014 ◽  
Vol 41 (2) ◽  
pp. 203-212 ◽  
Author(s):  
Suyong Yeon ◽  
ChangHyun Jun ◽  
Hyunga Choi ◽  
Jaehyeon Kang ◽  
Youngmok Yun ◽  
...  
Keyword(s):  
Principal Component ◽  
Point Clouds ◽  
Previous Method ◽  
Divide And Conquer ◽  
Sensor Data ◽  
Estimation Accuracy ◽  
Content Type ◽  
Extraction Algorithm ◽  
Plane Extraction ◽  
Scan Data

Purpose – The authors aim to propose a novel plane extraction algorithm for geometric 3D indoor mapping with range scan data. Design/methodology/approach – The proposed method utilizes a divide-and-conquer step to efficiently handle huge amounts of point clouds not in a whole group, but in forms of separate sub-groups with similar plane parameters. This method adopts robust principal component analysis to enhance estimation accuracy. Findings – Experimental results verify that the method not only shows enhanced performance in the plane extraction, but also broadens the domain of interest of the plane registration to an information-poor environment (such as simple indoor corridors), while the previous method only adequately works in an information-rich environment (such as a space with many features). Originality/value – The proposed algorithm has three advantages over the current state-of-the-art method in that it is fast, utilizes more inlier sensor data that does not become contaminated by severe sensor noise and extracts more accurate plane parameters.

Aspects of project learning in construction: a socio-technical model

2014 ◽  
Vol 14 (2) ◽  
pp. 229-244 ◽  
Author(s):  
Ali Mohammed Alashwal ◽  
Hamzah Abdul-Rahman
Keyword(s):  
Latent Variable ◽  
Construction Projects ◽  
Team Building ◽  
Principal Component ◽  
Measurement Model ◽  
Survey Method ◽  
Path Modeling ◽  
Content Type ◽  
Measurement Models ◽  
Project Learning

Purpose – The purpose of this paper is to determine the measurement constructs of learning within construction projects' milieu. The literature indicated some mechanisms of learning in projects under four aspects, namely knowledge sharing, knowledge creation, team action to learn, and learning support. The empirical study attempts to verify whether intra-project learning can be measured through these aspects. Design/methodology/approach – The study used a survey method to collect the data from 36 mega-sized building projects in Malaysia. In total, 203 questionnaires were collected from professionals working in the sites of these projects. The data were analysed using principal component analysis (PCA) to determine the constructs of intra-project learning. Partial least squares-path modeling was used then to confirm the results of PCA and determine the contribution of each construct to intra-project learning. Findings – The results affirmed two constructs of intra-project learning, named, social and technical and each consisted of four indicators of learning. Originality/value – The paper emphasized the socio-technical perspective of learning and contributed to developing a hierarchical measurement model of learning in construction project. A project manager can propose new initiatives in response to the new perspective of learning for team building and continuous development. Lastly, the paper provides a comprehensive presentation of how to estimate the hierarchical measurement models of project learning as a latent variable.

A principal component analysis of the determinants of spatial disparity between rural and urban localities of Ghana

2017 ◽  
Vol 44 (6) ◽  
pp. 715-731 ◽  
Author(s):  
Ivy Drafor
Keyword(s):  
Principal Component Analysis ◽  
Rural Areas ◽  
Urban Areas ◽  
Principal Component ◽  
Component Analysis ◽  
Spatial Inequality ◽  
Necessary Condition ◽  
Spatial Disparity ◽  
Content Type ◽  
Rural And Urban

Purpose The purpose of this paper is to analyse the spatial disparity between rural and urban areas in Ghana using the Ghana Living Standards Survey’s (GLSS) rounds 5 and 6 data to advance the assertion that an endowed rural sector is necessary to promote agricultural development in Ghana. This analysis helps us to know the factors that contribute to the depravity of the rural sectors to inform policy towards development targeting. Design/methodology/approach A multivariate principal component analysis (PCA) and hierarchical cluster analysis were applied to data from the GLSS-5 and GLSS-6 to determine the characteristics of the rural-urban divide in Ghana. Findings The findings reveal that the rural poor also spend 60.3 per cent of their income on food, while the urban dwellers spend 49 per cent, which is an indication of food production capacity. They have low access to information technology facilities, have larger household sizes and lower levels of education. Rural areas depend a lot on firewood for cooking and use solar/dry cell energies and kerosene for lighting which have implications for conserving the environment. Practical implications Developing the rural areas to strengthen agricultural growth and productivity is a necessary condition for eliminating spatial disparities and promoting overall economic development in Ghana. Addressing rural deprivation is important for conserving the environment due to its increased use of fuelwood for cooking. Absence of alternatives to the use of fuelwood weakens the efforts to reduce deforestation. Originality/value The application of PCA to show the factors that contribute to spatial inequality in Ghana using the GLSS-5 and GLSS-6 data is unique. The study provides insights into redefining the framework for national poverty reduction efforts.

The psychology quadrant: an outcome measure based on the START risk assessment

2017 ◽  
Vol 19 (1) ◽  
pp. 14-22
Author(s):  
Matthew John Gill ◽  
Samantha Brookes
Keyword(s):  
Risk Assessment ◽  
Factor Structure ◽  
Psychiatric Rehabilitation ◽  
Principal Component ◽  
Future Research ◽  
Psychological Outcome ◽  
Content Type ◽  
Health Rehabilitation ◽  
Mental Health Rehabilitation ◽  
Outcome Tool

Purpose The purpose of this paper is to develop a psychological outcome tool which reflects the relationship between clusters of items on the Short Term Assessment of Risk and Treatability (START) risk assessment and different categories of psychological progress in male inpatient psychiatric services. Design/methodology/approach A principal component analysis (PCA) was conducted on data from 135 male psychiatric rehabilitation patients’ START risk assessments. Findings PCA identified four strength psychology quadrants which were explained by a five-factor structure and four vulnerability quadrants which were explained by a four-factor structure. The development of the psychology quadrant, its usefulness in establishing a treatment pathway and areas of future research are also discussed. Originality/value Developing accessible, transparent outcome measures using evidence-based practice is highly relevant within the field of mental health rehabilitation.

Sign in / Sign up

Export Citation Format

Share Document