Pub Date : 2019-08-02DOI: 10.1080/25726838.2019.1637656
Joel Cebastien Shouop Guembou, Maurice Moyo Ndontchueng, Jilbert Eric Mekongtso Nguelem, G. Chéné, O. Motapon, Styve Arnol Kayo, D. Strivay
ABSTRACT This study aimed to determine the concentration of natural radionuclides, the chemical composition, and the geological provenance of sand samples from seven large quarries within the Douala Basin and surrounding locations within the Littoral Region of Cameroon along the Gulf of Guinea. The analyses were undertaken on a total of 24 samples, using both gamma- and X-ray spectrometry techniques. Gamma spectrometric results indicated that the samples from the study area contained amounts of natural radioactivity that are less than the globally agreed safe limits. X-ray fluorescence spectrometry yielded quantitative major, minor, and trace element concentrations that were used in tectonic discrimination diagrams, indicating that these sediments were deposited in a passive margin environment. These concentration and natural radionuclide radioactivity level data provide a reference database for this region of Cameroon as well as for the wider Gulf of Guinea. GRAPHICAL ABSTRACT
{"title":"Determination of the natural radioactivity, elemental composition and geological provenance of sands from Douala in the littoral region of Cameroon using X-ray and γ-ray spectrometry","authors":"Joel Cebastien Shouop Guembou, Maurice Moyo Ndontchueng, Jilbert Eric Mekongtso Nguelem, G. Chéné, O. Motapon, Styve Arnol Kayo, D. Strivay","doi":"10.1080/25726838.2019.1637656","DOIUrl":"https://doi.org/10.1080/25726838.2019.1637656","url":null,"abstract":"ABSTRACT This study aimed to determine the concentration of natural radionuclides, the chemical composition, and the geological provenance of sand samples from seven large quarries within the Douala Basin and surrounding locations within the Littoral Region of Cameroon along the Gulf of Guinea. The analyses were undertaken on a total of 24 samples, using both gamma- and X-ray spectrometry techniques. Gamma spectrometric results indicated that the samples from the study area contained amounts of natural radioactivity that are less than the globally agreed safe limits. X-ray fluorescence spectrometry yielded quantitative major, minor, and trace element concentrations that were used in tectonic discrimination diagrams, indicating that these sediments were deposited in a passive margin environment. These concentration and natural radionuclide radioactivity level data provide a reference database for this region of Cameroon as well as for the wider Gulf of Guinea. GRAPHICAL ABSTRACT","PeriodicalId":43298,"journal":{"name":"Applied Earth Science-Transactions of the Institutions of Mining and Metallurgy","volume":"128 1","pages":"167 - 180"},"PeriodicalIF":1.0,"publicationDate":"2019-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/25726838.2019.1637656","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47492317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-07-03DOI: 10.1080/25726838.2019.1600826
{"title":"Correction","authors":"","doi":"10.1080/25726838.2019.1600826","DOIUrl":"https://doi.org/10.1080/25726838.2019.1600826","url":null,"abstract":"","PeriodicalId":43298,"journal":{"name":"Applied Earth Science-Transactions of the Institutions of Mining and Metallurgy","volume":"128 1","pages":"134 - 134"},"PeriodicalIF":1.0,"publicationDate":"2019-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/25726838.2019.1600826","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42813089","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-07-03DOI: 10.1080/25726838.2019.1634897
M. Abzalov, R. Djenchuraeva, Ye. Alpiyev, S. Abzalov
ABSTRACT The Bozymchak Cu-Au skarn deposit is located in the Chatkal – Kurama region, approximately 130 km east from the Almalyk Cu-Au porphyry mine camp. The current paper provides the results from geochemical study and shows that geochemical characteristics of the Bozymchak area granitoids, including the rare-earth elements, are essentially similar to high-K calc-alkaline series magmatism of the Almalyk area. Systematic sampling of the Bozymchak granitoids has revealed the zoned distribution of several elements relative to the Cu-Au skarn. Most markedly, this is expressed by P2O5, MgO, Fe2O3 and V, whose contents decrease in the granitoids located closest to the skarns. The zoned distribution of base metals Cu, Zn, Pb, Mo, and also As, is less distinct, however, in general, their content decreases away from the skarns. This revealed geochemical zoning appears to represent a hydrothermal halo of Cu-Au bearing skarns and can potentially be used for guiding exploration in the region.
{"title":"The geology of the Bozymchak Cu-Au skarn deposit, Tien Shan belt, Central Asia: emphasis on the geochemical characteristics of the granitoids","authors":"M. Abzalov, R. Djenchuraeva, Ye. Alpiyev, S. Abzalov","doi":"10.1080/25726838.2019.1634897","DOIUrl":"https://doi.org/10.1080/25726838.2019.1634897","url":null,"abstract":"ABSTRACT The Bozymchak Cu-Au skarn deposit is located in the Chatkal – Kurama region, approximately 130 km east from the Almalyk Cu-Au porphyry mine camp. The current paper provides the results from geochemical study and shows that geochemical characteristics of the Bozymchak area granitoids, including the rare-earth elements, are essentially similar to high-K calc-alkaline series magmatism of the Almalyk area. Systematic sampling of the Bozymchak granitoids has revealed the zoned distribution of several elements relative to the Cu-Au skarn. Most markedly, this is expressed by P2O5, MgO, Fe2O3 and V, whose contents decrease in the granitoids located closest to the skarns. The zoned distribution of base metals Cu, Zn, Pb, Mo, and also As, is less distinct, however, in general, their content decreases away from the skarns. This revealed geochemical zoning appears to represent a hydrothermal halo of Cu-Au bearing skarns and can potentially be used for guiding exploration in the region.","PeriodicalId":43298,"journal":{"name":"Applied Earth Science-Transactions of the Institutions of Mining and Metallurgy","volume":"25 S63","pages":"106 - 123"},"PeriodicalIF":1.0,"publicationDate":"2019-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/25726838.2019.1634897","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41255939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-07-03DOI: 10.1080/25726838.2019.1650422
S. Jowitt
Welcome to issue three of volume 128 of Applied Earth Science. This issue showcases some of the breadth of research published in Applied Earth Science and starts with a paper by Johannesson et al. (2019), who focus on a somewhat atypical use for basalt, the most common rock on Earth’s surface. The use of basalt as a building stone and aggregate is well known, but it can also be cast for use in industrial applications that make use of the natural characteristics of the stone. However, Johannesson et al. (2019) examine another potential use of basalt from Iceland in the form of material that can be used to generate continuous basalt fibres, a substance that has better physicomechanical properties than fibreglass but (given the right feedstock) is cheaper to produce than carbon fibre. Their research indicates that although no single Icelandic basalt sampled during their study is ideally suited for use as a basalt fibre feedstock, the addition of small amounts of CaO to some of their samples significantly improves the potential of these basalts, suggesting that Iceland may be capable of providing basalt that can be used in this manufacturing process. The second paper in this volume outlines a potential addition to the mine planning toolbox by examining an unmanned aerial vehicle (UAV; sometimes known as drones) approach to lithological classification within an open pit phosphate mine in Brazil (Beretta et al. 2019). The authors assessed the viability of surface feature detection using visible light-based data and machine learning-based algorithms to generate a complete geological model for the mine. This model was then compared to a geological model obtained using traditional methods. The comparison indicated the usefulness of the UAV-based approach, which is not just quicker and potentially cheaper but is also safer than manual face mapping as operators do not need to be within the mine to acquire data. This is still an area that requires further research but this study outlines the potential use of this approach in moving towards more automated geological mapping systems. Parnell et al. (2019) change the focus of the issue towards more traditional economic geology-type research and present the results of the analysis of gases trapped within sulphide minerals in a number of areas of Palaeozoic gold mineralisation in Britain and Ireland. These data indicate that mineralisation hosted by Carboniferous cover units contains less non-aqueous gas than mineralisation hosted by greenschist units. In addition, combining the gas data presented in the study with the results of fluid inclusion microthermometry suggests that organic species may have a role in the genesis of orogenic gold mineralisation in addition to suggesting a potential role for trapped gas analysis in mineral exploration. The next paper in the issue provides an overview of the use of a mineral norm calculation in resource estimation, focusing on theMississippi Valley-type (MVT) sulphide and
欢迎来到《应用地球科学》128卷的第三期。本期杂志展示了《应用地球科学》杂志上发表的一些研究的广度,并从Johannesson等人(2019年)的一篇论文开始,他们专注于玄武岩的一种非典型用途,玄武岩是地球表面最常见的岩石。玄武岩作为建筑石材和骨料的使用是众所周知的,但它也可以铸造用于工业应用,利用石材的自然特性。然而,Johannesson等人(2019)研究了冰岛玄武岩的另一种潜在用途,即可用于生产连续玄武岩纤维的材料,这种物质比玻璃纤维具有更好的物理力学性能,但(如果原料合适)生产成本比碳纤维低。他们的研究表明,尽管在他们的研究中,没有一个冰岛玄武岩样本是理想的,适合用作玄武岩纤维原料,但在一些样本中添加少量的CaO显著提高了这些玄武岩的潜力,这表明冰岛可能有能力提供可以用于这种制造过程的玄武岩。本卷中的第二篇论文概述了通过检查无人驾驶飞行器(UAV;有时被称为无人机)在巴西的一个露天磷矿中进行岩性分类的方法(Beretta et al. 2019)。作者使用基于可见光的数据和基于机器学习的算法评估了地表特征检测的可行性,从而为矿山生成完整的地质模型。然后将该模型与使用传统方法获得的地质模型进行了比较。对比表明了基于无人机的方法的实用性,它不仅更快,可能更便宜,而且比手动人脸映射更安全,因为操作人员不需要在矿井内获取数据。这仍然是一个需要进一步研究的领域,但这项研究概述了这种方法在迈向更自动化的地质测绘系统方面的潜在用途。Parnell等人(2019)将问题的焦点转向更传统的经济地质类型研究,并介绍了英国和爱尔兰一些古生代金矿化地区硫化物矿物中捕获气体的分析结果。这些数据表明,石炭系盖层单元承载的矿化比绿片岩单元承载的矿化含有更少的非水气体。此外,结合流体包裹体显微测温结果表明,有机物种可能在造山带金矿化的成因中起作用,并提示了圈闭气体分析在矿产勘探中的潜在作用。本期的下一篇论文概述了在资源估算中使用矿物规范计算的情况,重点介绍了秘鲁佛罗里达峡谷矿床的密西西比河谷型(MVT)硫化物和非硫化物Zn-Pb矿化(de Oliveira et al. 2019)。de Oliveira和Saldanha(2019)采用的方法使用Zn、Pb和S的浓度来计算块模型中闪锌矿、方铅矿和非硫化物矿物的丰度,从而可以详细检查矿床中硫化物和非硫化物矿化之间的几何和空间关系。考虑到硫化物和非硫化物矿石类型需要不同的加工类型,理解这些关系是关键,不仅是为了进一步了解形成该矿床的成矿系统,也是为了矿山规划和矿物加工。作者概述的简单算法易于使用,并提供了一种在涉及混合矿石类型的矿物资源评价中可使用的方法;这里的应用是mvt型矿化,但这种方法也可以用于其他矿化系统,包含不同的矿石类型(如氧化物和硫化物矿石)。这期的倒数第二篇论文概述了中亚天山带的一个铜金夕卡岩矿床的地质情况。在此,Abzalov等(2019)提出了新的矿床地球化学数据,并认为与Bozymchak铜金矽卡岩矿床相关的花岗岩类在地球化学上与距离研究区约130 km的Almalyk铜金斑岩矿床相关的高钾钙碱岩浆作用相似。该区花岗岩类也具有地球化学分带性,表明该分带可作为该类矽卡岩矿化勘探的矢量。最后,但并非最不重要的是,本期是Gaboury(2019)的一篇论文,他概述了造山带金系统中的关键参数。这些矿床占全球原生金产量的很大比例,形成于太古宙和显生宙之间,地壳深度通常为40 ~ 40 km。Gaboury
{"title":"Editorial","authors":"S. Jowitt","doi":"10.1080/25726838.2019.1650422","DOIUrl":"https://doi.org/10.1080/25726838.2019.1650422","url":null,"abstract":"Welcome to issue three of volume 128 of Applied Earth Science. This issue showcases some of the breadth of research published in Applied Earth Science and starts with a paper by Johannesson et al. (2019), who focus on a somewhat atypical use for basalt, the most common rock on Earth’s surface. The use of basalt as a building stone and aggregate is well known, but it can also be cast for use in industrial applications that make use of the natural characteristics of the stone. However, Johannesson et al. (2019) examine another potential use of basalt from Iceland in the form of material that can be used to generate continuous basalt fibres, a substance that has better physicomechanical properties than fibreglass but (given the right feedstock) is cheaper to produce than carbon fibre. Their research indicates that although no single Icelandic basalt sampled during their study is ideally suited for use as a basalt fibre feedstock, the addition of small amounts of CaO to some of their samples significantly improves the potential of these basalts, suggesting that Iceland may be capable of providing basalt that can be used in this manufacturing process. The second paper in this volume outlines a potential addition to the mine planning toolbox by examining an unmanned aerial vehicle (UAV; sometimes known as drones) approach to lithological classification within an open pit phosphate mine in Brazil (Beretta et al. 2019). The authors assessed the viability of surface feature detection using visible light-based data and machine learning-based algorithms to generate a complete geological model for the mine. This model was then compared to a geological model obtained using traditional methods. The comparison indicated the usefulness of the UAV-based approach, which is not just quicker and potentially cheaper but is also safer than manual face mapping as operators do not need to be within the mine to acquire data. This is still an area that requires further research but this study outlines the potential use of this approach in moving towards more automated geological mapping systems. Parnell et al. (2019) change the focus of the issue towards more traditional economic geology-type research and present the results of the analysis of gases trapped within sulphide minerals in a number of areas of Palaeozoic gold mineralisation in Britain and Ireland. These data indicate that mineralisation hosted by Carboniferous cover units contains less non-aqueous gas than mineralisation hosted by greenschist units. In addition, combining the gas data presented in the study with the results of fluid inclusion microthermometry suggests that organic species may have a role in the genesis of orogenic gold mineralisation in addition to suggesting a potential role for trapped gas analysis in mineral exploration. The next paper in the issue provides an overview of the use of a mineral norm calculation in resource estimation, focusing on theMississippi Valley-type (MVT) sulphide and ","PeriodicalId":43298,"journal":{"name":"Applied Earth Science-Transactions of the Institutions of Mining and Metallurgy","volume":"128 1","pages":"71 - 72"},"PeriodicalIF":1.0,"publicationDate":"2019-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/25726838.2019.1650422","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45270776","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-05-23DOI: 10.1080/25726838.2019.1619057
S. D. de Oliveira, A. A. Saldanha
ABSTRACT Both Zn–Pb hypogene sulphide and Zn supergene non-sulphide mineralisation types occur in the Mississippi Valley-type deposit of Florida Canyon, located in northern Peru. The geometry and spatial relationship between the two ore types are very complex to interpret, when it comes to mineral resource evaluation. An algorithm using the Zn, Pb and S contents is proposed for the calculation of sphalerite, galena and non-sulphide norms in the block model after its conventional ordinary kriging estimation. Model validation was performed by comparing the results of the calculations with available SEM/EDS-MLA data. The results show good correlation between the calculated and the quantitative values, thus accrediting the proposed methodology. The algorithm is simple and fast to use and can be applied to mineral resource evaluation of Zn–Pb MVT deposits associated with non-sulphide mineralisation.
{"title":"Application of mineral norm calculation in the resource evaluation of the sulphide and non-sulphide Zn-Pb mineralisation of the Florida Canyon MVT deposit, Peru","authors":"S. D. de Oliveira, A. A. Saldanha","doi":"10.1080/25726838.2019.1619057","DOIUrl":"https://doi.org/10.1080/25726838.2019.1619057","url":null,"abstract":"ABSTRACT Both Zn–Pb hypogene sulphide and Zn supergene non-sulphide mineralisation types occur in the Mississippi Valley-type deposit of Florida Canyon, located in northern Peru. The geometry and spatial relationship between the two ore types are very complex to interpret, when it comes to mineral resource evaluation. An algorithm using the Zn, Pb and S contents is proposed for the calculation of sphalerite, galena and non-sulphide norms in the block model after its conventional ordinary kriging estimation. Model validation was performed by comparing the results of the calculations with available SEM/EDS-MLA data. The results show good correlation between the calculated and the quantitative values, thus accrediting the proposed methodology. The algorithm is simple and fast to use and can be applied to mineral resource evaluation of Zn–Pb MVT deposits associated with non-sulphide mineralisation.","PeriodicalId":43298,"journal":{"name":"Applied Earth Science-Transactions of the Institutions of Mining and Metallurgy","volume":"128 1","pages":"105 - 96"},"PeriodicalIF":1.0,"publicationDate":"2019-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/25726838.2019.1619057","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46901098","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-05-05DOI: 10.1080/25726838.2019.1611089
Yemane Gebru, A. A. Elueze, K. Amare, Franck Wilfried Nguimatsia Dongmo
ABSTRACT The ferricrete deposit in Adi Kokeb district was investigated using field observations, petrographic studies and chemical analysis of samples for their geochemistry and mode of origin. Field observations confirmed the presence of kaolinites, thin iron bands and relict quartz veins. Petrographic studies of the samples revealed that quartz, sericite, muscovite, orthoclase feldspar and iron oxides/hydroxides are the dominant minerals. Geochemical determination of major, minor and trace elements of seventeen (17) samples were done using X-ray fluorescence (XRF). The results show a general increasing trend in Fe2O3 (16.75–57.9 wt.%) and Al2O3 (11.35–16.44 wt.%) values and decreasing trends in SiO2 (57.05–22.01 wt.%) values from the Meta-sandstone to the ferricrete. The alkali and alkaline earth elements, notably K2O (0.142 wt.%), Na2O (<0.005 wt.%), CaO (0.075 wt.%) and MgO (0.098 wt.%), are highly depleted, confirming that iron precipitation with subsequent oxidation is major process in ferricrete formation. Similarly, the minor elements such as MnO (0.17 wt.%), TiO2 (0.56 wt.%) and P2O5 (0.154 wt.%) are highly depleted, implying their weak substitution for major elements in the ferricrete. The average value of trace elements such as Ba (669 ppm), Zr (348 ppm), Sr (215 ppm), Cu (125 ppm), Zn (55 ppm) and Pb (9.5 ppm) show a relative enrichment of the ferricrete compared to ferruginous sandstone and meta-sandstone. The relatively high concentrations of Zr, Ba and Sr in the ferricrete are attributed to their presence in detrital material during weathering (Zr) and their adsorption on neo-formed kaolinite (Ba and Sr). Integration of field, petrographic and geochemical results suggest that the origin of this deposit is associated with weathering processes. Therefore, the deposit is likely to be a ferricrete.
{"title":"Compositional characteristics and genetic affinity of the ferricrete deposit in Adi Kokeb district, northwestern Tigray, Ethiopia","authors":"Yemane Gebru, A. A. Elueze, K. Amare, Franck Wilfried Nguimatsia Dongmo","doi":"10.1080/25726838.2019.1611089","DOIUrl":"https://doi.org/10.1080/25726838.2019.1611089","url":null,"abstract":"ABSTRACT The ferricrete deposit in Adi Kokeb district was investigated using field observations, petrographic studies and chemical analysis of samples for their geochemistry and mode of origin. Field observations confirmed the presence of kaolinites, thin iron bands and relict quartz veins. Petrographic studies of the samples revealed that quartz, sericite, muscovite, orthoclase feldspar and iron oxides/hydroxides are the dominant minerals. Geochemical determination of major, minor and trace elements of seventeen (17) samples were done using X-ray fluorescence (XRF). The results show a general increasing trend in Fe2O3 (16.75–57.9 wt.%) and Al2O3 (11.35–16.44 wt.%) values and decreasing trends in SiO2 (57.05–22.01 wt.%) values from the Meta-sandstone to the ferricrete. The alkali and alkaline earth elements, notably K2O (0.142 wt.%), Na2O (<0.005 wt.%), CaO (0.075 wt.%) and MgO (0.098 wt.%), are highly depleted, confirming that iron precipitation with subsequent oxidation is major process in ferricrete formation. Similarly, the minor elements such as MnO (0.17 wt.%), TiO2 (0.56 wt.%) and P2O5 (0.154 wt.%) are highly depleted, implying their weak substitution for major elements in the ferricrete. The average value of trace elements such as Ba (669 ppm), Zr (348 ppm), Sr (215 ppm), Cu (125 ppm), Zn (55 ppm) and Pb (9.5 ppm) show a relative enrichment of the ferricrete compared to ferruginous sandstone and meta-sandstone. The relatively high concentrations of Zr, Ba and Sr in the ferricrete are attributed to their presence in detrital material during weathering (Zr) and their adsorption on neo-formed kaolinite (Ba and Sr). Integration of field, petrographic and geochemical results suggest that the origin of this deposit is associated with weathering processes. Therefore, the deposit is likely to be a ferricrete.","PeriodicalId":43298,"journal":{"name":"Applied Earth Science-Transactions of the Institutions of Mining and Metallurgy","volume":"128 1","pages":"146 - 157"},"PeriodicalIF":1.0,"publicationDate":"2019-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/25726838.2019.1611089","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43604815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-04-03DOI: 10.1080/25726838.2019.1601359
R. Crossley, M. Yudovskaya, J. Van Schelatema, M. McCreesh, J. Kinnaird
The boundary between the Upper Zone andMain Zone of the Bushveld Complex is considered to be marked by the first appearance of cumulus magnetite (Eales and Cawthorn 1996). Magnetite associated with the Upper Zone in the northern limb is titanium and vanadium rich (Ashwal et al. 2005). The Main Zone contains a low modal abundance of magnetite that differs from Upper Zone magnetite, with an intercumulus texture and lower concentrations of titanium and vanadium (Ashwal et al. 2005). Whether the Cu–Ni–platinum group element (PGE)–Au mineralisation of the Aurora project and the T Zone of the Waterberg project in the far northern limb is hosted in the Main Zone or Upper Zone remains uncertain. Furthermore, the relationship between the Aurora andWaterberg mineralisation is not fully understood. However, a possible link between the Aurora mineralisation to the south of the Hout River Shear Zone (HRSZ), and the T Zone mineralisation of the Waterberg project to the north of the HRSZ has been inferred previously (McDonald et al. 2017). Alternatively, a separate magmatic basin may have been present north of the HRSZ (Huthmann et al. 2017; Kinnaird et al. 2017; Huthmann et al. 2018). On the basis of mineral chemistry, the mineralisation at La Pucella of the Aurora project has been attributed to the Upper Main Zone of the Bushveld Complex (McDonald et al. 2017). However, the presence of cumulus magnetite in a La Pucella gabbroic unit is not consistent with Main Zone mineralisation (McDonald et al. 2017). To investigate whether the mineralisation of the Aurora project relates to the Upper Zone or Main Zone, we analysed magnetite grains in mineralised leucocratic rocks from Harriet’s Wish, Kransplaats and La Pucella sections of the Aurora project. Aurora magnetite compositions are compared to those from the mineralised T Zone of the Waterberg project. Magnetite grains were characterised in terms of cumulus or intercumulus textures, where the latter could reflect Main Zone magnetite (Ashwal et al. 2005). We compare the results to those previously reported for the Upper Zone and Main Zone magnetite from the Bellevue core (Ashwal et al. 2005). The analysed cumulus magnetite grains are enriched in vanadium, a characteristic of Upper Zone magnetite. However, these magnetites have relatively low concentrations of titanium, and high concentrations of Fe compared to Upper Zone magnetites from the Bellevue core (Ashwal et al. 2005). The relatively Ti-poor and Fe composition is attributed to the exsolution of ilmenite lamellae from former titanomagnetite/ulvöspinel, a feature observed previously in the Upper Zone (von Gruenewaldt et al. 1985). Therefore, the magnetite chemistry is most consistent with the Upper Zone. No significant differences in magnetite chemistry between the Aurora and Waterberg deposits were identified, supporting a possible connection of the two deposits.
Bushveld杂岩的上部带和主带之间的边界被认为是首次出现积云磁铁矿的标志(Eales和Cawthorn,1996年)。与北翼上部带相关的磁铁矿富含钛和钒(Ashwal等人,2005)。主带磁铁矿的模式丰度较低,与上带磁铁矿不同,具有结核间结构,钛和钒的浓度较低(Ashwal等人,2005)。Aurora项目的Cu–Ni–铂族元素(PGE)–Au矿化带和远北翼Waterberg项目的T区是否位于主带或上带仍不确定。此外,Aurora和Waterberg矿化之间的关系尚不完全清楚。然而,Hout河剪切带(HRSZ)以南的Aurora矿化与HRSZ以北的Waterberg项目的T区矿化之间可能存在联系(McDonald等人,2017)。或者,HRSZ北部可能存在一个单独的岩浆盆地(Huthmann等人,2017;Kinnaird等人,2017年;Huthmann et al.2018)。根据矿物化学,Aurora项目La Pucella的矿化作用被归因于Bushveld杂岩的上部主带(McDonald等人,2017)。然而,La Pucella辉长岩单元中积云磁铁矿的存在与主带矿化不一致(McDonald等人,2017)。为了调查Aurora项目的矿化是否与上带或主带有关,我们分析了Aurora工程Harriet’s Wish、Kransplaats和La Pucella段的矿化隐色岩中的磁铁矿颗粒。Aurora磁铁矿的成分与Waterberg项目矿化T区的成分进行了比较。磁铁矿颗粒的特征是积云或积云间纹理,后者可以反映主带磁铁矿(Ashwal等人,2005)。我们将结果与之前报道的贝尔维尤岩芯中上部区域和主区域磁铁矿的结果进行了比较(Ashwal等人,2005)。分析的积云磁铁矿颗粒富含钒,这是上带磁铁矿的特征。然而,与贝尔维尤岩芯的上区磁铁矿相比,这些磁铁矿的钛浓度相对较低,Fe浓度较高(Ashwal等人,2005)。相对贫钛和贫铁的成分归因于前钛磁铁矿/ulvö尖晶石中钛铁矿片层的出溶,这是以前在上部区域观察到的特征(von Gruenewaldt等人,1985)。因此,磁铁矿的化学性质与上部区域最为一致。Aurora矿床和Waterberg矿床之间的磁铁矿化学成分没有发现显著差异,这支持了这两个矿床之间的可能联系。
{"title":"Magnetite chemistry of the Far Northern Limb of the Bushveld Complex","authors":"R. Crossley, M. Yudovskaya, J. Van Schelatema, M. McCreesh, J. Kinnaird","doi":"10.1080/25726838.2019.1601359","DOIUrl":"https://doi.org/10.1080/25726838.2019.1601359","url":null,"abstract":"The boundary between the Upper Zone andMain Zone of the Bushveld Complex is considered to be marked by the first appearance of cumulus magnetite (Eales and Cawthorn 1996). Magnetite associated with the Upper Zone in the northern limb is titanium and vanadium rich (Ashwal et al. 2005). The Main Zone contains a low modal abundance of magnetite that differs from Upper Zone magnetite, with an intercumulus texture and lower concentrations of titanium and vanadium (Ashwal et al. 2005). Whether the Cu–Ni–platinum group element (PGE)–Au mineralisation of the Aurora project and the T Zone of the Waterberg project in the far northern limb is hosted in the Main Zone or Upper Zone remains uncertain. Furthermore, the relationship between the Aurora andWaterberg mineralisation is not fully understood. However, a possible link between the Aurora mineralisation to the south of the Hout River Shear Zone (HRSZ), and the T Zone mineralisation of the Waterberg project to the north of the HRSZ has been inferred previously (McDonald et al. 2017). Alternatively, a separate magmatic basin may have been present north of the HRSZ (Huthmann et al. 2017; Kinnaird et al. 2017; Huthmann et al. 2018). On the basis of mineral chemistry, the mineralisation at La Pucella of the Aurora project has been attributed to the Upper Main Zone of the Bushveld Complex (McDonald et al. 2017). However, the presence of cumulus magnetite in a La Pucella gabbroic unit is not consistent with Main Zone mineralisation (McDonald et al. 2017). To investigate whether the mineralisation of the Aurora project relates to the Upper Zone or Main Zone, we analysed magnetite grains in mineralised leucocratic rocks from Harriet’s Wish, Kransplaats and La Pucella sections of the Aurora project. Aurora magnetite compositions are compared to those from the mineralised T Zone of the Waterberg project. Magnetite grains were characterised in terms of cumulus or intercumulus textures, where the latter could reflect Main Zone magnetite (Ashwal et al. 2005). We compare the results to those previously reported for the Upper Zone and Main Zone magnetite from the Bellevue core (Ashwal et al. 2005). The analysed cumulus magnetite grains are enriched in vanadium, a characteristic of Upper Zone magnetite. However, these magnetites have relatively low concentrations of titanium, and high concentrations of Fe compared to Upper Zone magnetites from the Bellevue core (Ashwal et al. 2005). The relatively Ti-poor and Fe composition is attributed to the exsolution of ilmenite lamellae from former titanomagnetite/ulvöspinel, a feature observed previously in the Upper Zone (von Gruenewaldt et al. 1985). Therefore, the magnetite chemistry is most consistent with the Upper Zone. No significant differences in magnetite chemistry between the Aurora and Waterberg deposits were identified, supporting a possible connection of the two deposits.","PeriodicalId":43298,"journal":{"name":"Applied Earth Science-Transactions of the Institutions of Mining and Metallurgy","volume":"128 1","pages":"43 - 43"},"PeriodicalIF":1.0,"publicationDate":"2019-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/25726838.2019.1601359","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48663074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-04-03DOI: 10.1080/25726838.2019.1607200
F. Craig, H. Claridge, R. Shail, C. Yeomans, G. Rollinson, B. Colgan
{"title":"The characterisation of Cornish crosscourses","authors":"F. Craig, H. Claridge, R. Shail, C. Yeomans, G. Rollinson, B. Colgan","doi":"10.1080/25726838.2019.1607200","DOIUrl":"https://doi.org/10.1080/25726838.2019.1607200","url":null,"abstract":"","PeriodicalId":43298,"journal":{"name":"Applied Earth Science-Transactions of the Institutions of Mining and Metallurgy","volume":"128 1","pages":"67 - 68"},"PeriodicalIF":1.0,"publicationDate":"2019-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/25726838.2019.1607200","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49551155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-04-03DOI: 10.1080/25726838.2019.1604059
S. Jowitt
{"title":"Editorial","authors":"S. Jowitt","doi":"10.1080/25726838.2019.1604059","DOIUrl":"https://doi.org/10.1080/25726838.2019.1604059","url":null,"abstract":"","PeriodicalId":43298,"journal":{"name":"Applied Earth Science-Transactions of the Institutions of Mining and Metallurgy","volume":"128 1","pages":"37 - 37"},"PeriodicalIF":1.0,"publicationDate":"2019-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/25726838.2019.1604059","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45330381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-04-03DOI: 10.1080/25726838.2019.1599203
D. Blanks, D. Holwell, S. Barnes, A. Boyce
among many others. A potentially significant one for the assurance of ethical and responsible mineral sourcing is the Initiative for Responsible Mining Assurance, currently being rolled out. But the viability and effectiveness of such schemes is often contested and depends on their having demonstrable value to and engagement frommultiple actors across complex interacting supply chains and value chains, including mining companies, manufacturers, investors, retailers, and end-point consumers. Public attention and changes in attitude to corporate ethics and governance can gather pace very rapidly, as demonstrated in recent years in the U.K. by consumer backlashes towards corporations perceived not to be paying a fair amount of tax. It may very quickly become valuable to miners, manufacturers and retailers alike, all concerned to ‘do the right thing’ as well as to anticipate their customers’ ethical concerns, for there to be a credible, transparent and easily comprehensible publicfacing ‘kitemark’ for responsibly sourced minerals and products manufactured using such minerals, akin to the Fairtrade or Forestry Stewardship Council schemes. But defining what such a kitemark should denote and implementing its uptake are likely to be highly challenging. Building on its November 2017 meeting on ‘Mining for the Future’, held in conjunction with the IUGS RFG initiative, the Geological Society convened two workshops in London (May 2018) and Vancouver (June 2018), bringing together actors from across the value chain plus researchers from the U.K. and internationally, to explore how they would assess the value and viability of responsible sourcing schemes; what characteristics would be required for these to be taken up across the chain; and how they can be made transparent and meaningful to end-point consumers. This presentation will report the conclusions of the workshops and will outline a PhD research project now under way to explore these challenges.
{"title":"Unravelling the dynamic emplacement of the carbonate-rich Munali Ni–Cu–PGE breccia deposit, Zambia","authors":"D. Blanks, D. Holwell, S. Barnes, A. Boyce","doi":"10.1080/25726838.2019.1599203","DOIUrl":"https://doi.org/10.1080/25726838.2019.1599203","url":null,"abstract":"among many others. A potentially significant one for the assurance of ethical and responsible mineral sourcing is the Initiative for Responsible Mining Assurance, currently being rolled out. But the viability and effectiveness of such schemes is often contested and depends on their having demonstrable value to and engagement frommultiple actors across complex interacting supply chains and value chains, including mining companies, manufacturers, investors, retailers, and end-point consumers. Public attention and changes in attitude to corporate ethics and governance can gather pace very rapidly, as demonstrated in recent years in the U.K. by consumer backlashes towards corporations perceived not to be paying a fair amount of tax. It may very quickly become valuable to miners, manufacturers and retailers alike, all concerned to ‘do the right thing’ as well as to anticipate their customers’ ethical concerns, for there to be a credible, transparent and easily comprehensible publicfacing ‘kitemark’ for responsibly sourced minerals and products manufactured using such minerals, akin to the Fairtrade or Forestry Stewardship Council schemes. But defining what such a kitemark should denote and implementing its uptake are likely to be highly challenging. Building on its November 2017 meeting on ‘Mining for the Future’, held in conjunction with the IUGS RFG initiative, the Geological Society convened two workshops in London (May 2018) and Vancouver (June 2018), bringing together actors from across the value chain plus researchers from the U.K. and internationally, to explore how they would assess the value and viability of responsible sourcing schemes; what characteristics would be required for these to be taken up across the chain; and how they can be made transparent and meaningful to end-point consumers. This presentation will report the conclusions of the workshops and will outline a PhD research project now under way to explore these challenges.","PeriodicalId":43298,"journal":{"name":"Applied Earth Science-Transactions of the Institutions of Mining and Metallurgy","volume":"128 1","pages":"39 - 40"},"PeriodicalIF":1.0,"publicationDate":"2019-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1080/25726838.2019.1599203","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41590368","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}