Journal articles: 'Pathfinder elements'

1

Korshunova, Vera, and Marina Charykova. "Mobile Forms of Gold and Pathfinder Elements in Surface Sediments at the Novye Peski Gold Deposit and in the Piilola Prospecting Area (Karelia Region)." Minerals 9, no. 1 (January 11, 2019): 34. http://dx.doi.org/10.3390/min9010034.

Full text

Abstract:

The success of prospecting for gold deposit in overburdened areas based on the using of secondary dispersion haloes mostly depends on the chosen method of geochemical survey (sampling horizon, sample preparation for analysis, etc.). At the same time, the geochemistry of gold in the supergene zone is insufficiently studied, especially it’s migration and concentration in association with other elements in surface sediments due to weathering of gold-bearing ore. The main aim of the study presented in this paper is the determination of mobile forms of gold and pathfinder elements (As, Cu, Ni, Ag, Zn, Pb, Se, Sb, Mo, Bi, and Te) in podzol soil and moraine in the areas of Karelia region with known gold mineralization. As a result of conducted experiments it was determined that the main mobile forms of gold are water-soluble and bound to organic matter, while pathfinder elements bound preferably to Fe and Mn(hydr)oxides and to organic matter. As gold and some pathfinders bind with organic matter, this form was considered in more detail, and the elements’ interaction with humic and fulvic acids was investigated. In addition, it was determined that the studied elements are quite “mobile” because the percentage of the mobile form in their total content was mostly more than 50%. The main features of the elements’ migration and concentration were identified in surface sediments of the study areas.

APA, Harvard, Vancouver, ISO, and other styles

2

Fuge, R., M. J. Andrews, and C. C. Johnson. "Chlorine and iodine, potential pathfinder elements in exploration geochemistry." Applied Geochemistry 1, no. 1 (January 1986): 111–16. http://dx.doi.org/10.1016/0883-2927(86)90042-9.

Full text

APA, Harvard, Vancouver, ISO, and other styles

3

Godfray, Godson. "Geochemical evaluation of the in situ regolith at Madengi Hill, Dodoma, Tanzania: implications for bedrock mapping and delineating gold mineralization targets." Geochemistry: Exploration, Environment, Analysis 22, no. 1 (November 24, 2021): geochem2021–074. http://dx.doi.org/10.1144/geochem2021-074.

Full text

Abstract:

Successful gold exploration projects depend on a piece of clear information on the association between gold, trace elements and mineralization controlling factors. The use of soil geochemistry has been an important tool in pinpointing exploration targets during the early stage of exploration. This study aimed to establish the gold distribution, the elemental association between gold and its pathfinder elements such as Cu, Zn, Ag, Ni, Co, Mn, Fe, Cd, V, Cr, Ti, Sc, In and Se, and identify lithologies contributing to the overlying residual soils. From cluster analysis, a high similarity level of 53.93% has been shown with Ag, Cd and Se at a distance level of 0.92. Au and Se have a similarity level of 65.87% and a distance level of 0.68; hence, is proposed to be the most promising pathfinder element. Principal component analysis (PCA), factor analysis (FA) and the Pearson's correlation matrix of transformed data of V, Cu, Ni, Fe, Mn, Cr and Co, and a stronger correlation between Pb and U, Th, Na, K, Sn, Y, Ta and Be shows that source gold mineralization might be associated with both hornblende gneisses interlayered with quartzite, tonalite and tonalitic orthogneiss. From the contour map and gridded map of Au and its pathfinder elements, it has been noted that their anomalies and generated targets are localized in the northern part of the area. The targets trend ESE–WNW, nearly parallel to the shear zones as a controlling factor of Au mineralization emplacement.Supplementary material: Concentration data for each of the 44 elements analysed are available at https://doi.org/10.6084/m9.figshare.c.5721965

APA, Harvard, Vancouver, ISO, and other styles

4

Williams, Kevin W., and Kurt M. Joseph. "Developing Data Link User-Interface Designs Using Pilot Conceptual Networks." Proceedings of the Human Factors and Ergonomics Society Annual Meeting 42, no. 1 (October 1998): 77–79. http://dx.doi.org/10.1177/154193129804200118.

Full text

Abstract:

One hundred and forty-eight pilots were asked to categorize a list of flight-related data elements that could be sent via data link from an FAA automated flight service station to an aircraft or vice versa. The categorization was used to construct a matrix of proximity values for each of the data-element pairs so that a conceptual network of the elements could be constructed using the Pathfinder algorithm developed by Schvaneveldt, Durso, and Dearholt (1985). Additionally, pilots were asked to judge each data element according to how useful the element was for the functions of communication, navigation, and surveillance within the general aviation (GA) flight environment. Elements scoring high on each of these flight-related functions were then subjected to a Pathfinder analysis. The conceptual networks that were created as a result of these analyses are discussed in relation to the development of data link user interfaces for the GA cockpit.

APA, Harvard, Vancouver, ISO, and other styles

5

Korshunova, V. A., E. D. Lodygin, M. V. Charykova, and S. N. Chukov. "Interaction of soil humic acids with gold ions and pathfinder elements." IOP Conference Series: Earth and Environmental Science 862, no. 1 (October 1, 2021): 012022. http://dx.doi.org/10.1088/1755-1315/862/1/012022.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

Grozdev, Valentin, Rossitsa Vassileva, and Irena Peytcheva. "The rare earth elements in zircons as pathfinder of geological events." Review of the Bulgarian Geological Society 83, no. 3 (December 2022): 93–96. http://dx.doi.org/10.52215/rev.bgs.2022.83.3.93.

Full text

Abstract:

The usual main purpose of the zircon investigation is to determine the precise age of particular rocks, applying the U-Pb isotope method. In this study we attempt to reveal the vast potential of zircons in understanding the magmatic and modification processes, as well as the structure of the deeper Earth’s interior, using the analysis of the zircon population of the major volcanic variety in the Ruen tectono-magmatic zone, Kyustendil area, SW Bulgaria. The ascending magmas crosscut different rock types and units along their path to the Earth’s surface. Using the zircon crystal analysis, we may make consideration about the age and chemical characteristics of these units. The trace and rare earth element (REE) content of the zircons brings insights for the rock formation time and discloses characteristics of the deeper parts of the Earth’s crust.

APA, Harvard, Vancouver, ISO, and other styles

7

Joyce, Nicholas, Daniel Layton-Matthews, Kurt Kyser, Matthew Leybourne, Kevin Ansdell, Tom Kotzer, David Quirt, and Gerard Zaluski. "Alteration mineralogy and pathfinder element inventory in the footprint of the McArthur River unconformity-related uranium deposit, Canada." Canadian Mineralogist 59, no. 5 (September 1, 2021): 985–1019. http://dx.doi.org/10.3749/canmin.2000067.

Full text

Abstract:

ABSTRACT Pathfinder elements associated with the exploration footprint of the McArthur River unconformity-related U deposit include U, radiogenic Pb, V, Ni, Co, Cu, Mo, As, Zn, and rare earth elements. In this study, the mineralogical and paragenetic context for their occurrence was established by integrating in situ mineral chemistry and laser ablation mass spectrometry chemical mapping of interstitial assemblages, detrital grains, and cements with whole-rock analyses of drill core samples from the diagenetically altered background and the hydrothermally altered sandstone host rocks. Diagenetically altered background sandstones contain a matrix assemblage of illite and dickite, with trace to minor aluminum-phosphate-sulfate (APS) minerals, apatite, and Fe-Ti oxide minerals. Aluminum-phosphate-sulfate minerals account for the majority of the Sr and light rare earth element concentrations, whereas early diagenetic apatite, monazite, and apatite inclusions in detrital quartz and detrital zircon contribute significant U and heavy rare earth elements to samples analyzed with an aggressive leach (partial digestion) such as aqua regia. Hydrothermally altered sandstone host rocks also contain variable assemblages of Al-Mg chlorite (sudoite), alkali-deficient tourmaline, APS minerals, kaolinite, illite, Fe-oxide, and sulfide minerals. Late pre-mineralization chlorite accounts for a significant portion of the observed Ni concentrations, whereas Co, Cu, Mo, and Zn occur predominantly in cryptic sub-micron sulfide and sulfarsenide inclusions within clay mineral aggregates and in association with Fe-Ti oxides. Elevated concentrations of U were observed in cryptic micro-inclusions associated with sulfides in quartz overgrowths, with Fe-Ti oxide micro-inclusions in kaolinite, and in post-mineralization Fe-oxide veins. The distribution of pathfinder elements throughout the deposit footprint appears to be less related to the primary dispersion of alteration minerals from the hydrothermal system than to the secondary dispersion of elements post-mineralization. Their occurrence throughout pre-, syn-, and post-mineralization assemblages further demonstrates the limitations to defining geochemical footprints from pathfinder element concentrations expressed in lithogeochemical data sets without structural, lithological, and mineralogical context.

APA, Harvard, Vancouver, ISO, and other styles

8

Balaram, V., and S. S. Sawant. "Indicator Minerals, Pathfinder Elements, and Portable Analytical Instruments in Mineral Exploration Studies." Minerals 12, no. 4 (March 23, 2022): 394. http://dx.doi.org/10.3390/min12040394.

Full text

Abstract:

Until recently, the classic approach to mineral exploration studies was to bring the field samples/drill cores collected during field studies to the laboratory, followed by laborious analysis procedures to generate the analytical data. This is very expensive, time-consuming, and difficult for exploring vast areas. However, rapid technological advances in field-portable analytical instruments, such as portable visible and near-infrared spectrophotometers, gamma-ray spectrometer, pXRF, pXRD, pLIBS, and µRaman spectrometer, have changed this scenario completely and increased their on-site applications in mineral exploration studies. LED fluorimeter is a potential portable tool in the hydrogeochemical prospecting studies of uranium. These instruments are currently providing direct, rapid, on-site, real-time, non-destructive, cost-effective identification, and determination of target elements, indicator minerals and pathfinder elements in rock, ore, soil, sediment, and water samples. These portable analytical instruments are currently helping to obtain accurate chemical and mineralogical information directly in the field with minimal or no sample preparation and providing decision-making support during fieldwork, as well as during drilling operations in several successful mineral exploration programs. In this article, the developments in these portable devices, and their contributions in the platinum group elements (PGE), rare earth elements (REE), gold, base metals, and lithium exploration studies both on land and on the ocean bed, have been summarized with examples.

APA, Harvard, Vancouver, ISO, and other styles

9

Osei, K. P., M. Affam, C. Kusi-Manu, and D. T. Kwapong. "Multivariate Statistical Evaluation of Geochemical Data from Quartz Vein-Associated Gold Mineralisation at the Badukrom Prospect within the Tarkwaian Base." Ghana Mining Journal 21, no. 1 (June 30, 2021): 22–30. http://dx.doi.org/10.4314/gm.v21i1.3.

Full text

Abstract:

The Kawere conglomerate at the base of the Tarkwaian Group in the Iduapriem Mine appears to show good prospect for hydrothermal gold mineralisation evidenced by major structures mapped from magnetic and Airborne Electromagnetic (AEM) geophysical data. Detailed geological mapping and sampling at Badukrom target which lies within the Kawere rocks confirm the presence of multiple structures as well as quartz veins indicative of potential hydrothermal gold mineralisation. Follow up soil sampling conducted within the area revealed a strong anomalous trend from the southern portion. Two diamond drilled (DD) holes pushed to delineate the extent of the anomalous zones returned narrow veins of significant gold intersections. Twenty-five (25) samples of the Badukrom hydrothermal Au mineralisation intersects were sent for analysis to ascertain the optimum pathfinder element suite for the hydrothermal targets within the Iduapriem concession. A total of fifty-nine elements were analysed via ICP-MS and ICP-OES. Multivariate statistical evaluation was carried out on the results to understand the geochemical associations of Au and the other elements to aid future exploration programmes planned for the hydrothermal targets. Multivariate analysis of the geochemical data using Pearson product-moment of correlation suggests a stronger positive correlation of gold with Iron, Antimony, Sulphur, Chromium, Vanadium respectively. However, the Spearman Rank correlation data indicates that, the optimum pathfinder elements for hydrothermal Au are: As, Sb and Te. Keywords: Tarkwaian Base, Statistical Evaluation, Hydrothermal Mineralisation, Geochemical Data

APA, Harvard, Vancouver, ISO, and other styles

10

Carocci, Eleonora, Christian Marignac, Michel Cathelineau, Laurent Truche, Andreï Lecomte, and Filipe Pinto. "Rutile from Panasqueira (Central Portugal): An Excellent Pathfinder for Wolframite Deposition." Minerals 9, no. 1 (December 24, 2018): 9. http://dx.doi.org/10.3390/min9010009.

Full text

Abstract:

Abundant W-rich rutile in the tourmalinized wall-rocks from the Panasqueira W-deposit appears to be a marker of the onset of the main wolframite depositing event. Rutile displays spectacular zoning, both sector (SZ) and oscillatory (OZ). An extensive set of compositional data obtained on crystals, beforehand studied using back-scattered electron images and X-ray maps, was used to address (i) the effects of SZ on differential trapping of minor elements, and (ii) the significance of the OZ in deciphering fluid sources and fluid circulation dynamics. Particular attention was paid to Sn, W (Nb, Ta) concentrations in rutile as pathfinders of the W deposition. Concerning the sector zoning, W is more incorporated than (Nb, Ta) onto more efficient faces, whereas Sn contents are nearly not impacted. The net effect of the sector zoning is thus a progressive increase of the relative weight of Sn from pyramid to prism faces, in combination with a less significant increase in the relative weight of Nb + Ta. The oscillatory zoning concerns most minor elements: W, Nb (Ta), Fe, V, Cr and Sn. In the frequent doublets, the clear bands are in general enriched in W relatively to the dark ones, whereas the inverse is true for Nb and Ta. The doublets may be viewed as the result of the successive influx of (i) a W-rich, Nb + Ta poor fluid, abruptly replaced by (or mixed to) (ii) a Nb + Ta-rich and W-poor fluid. The Nb + Ta-rich fluid could be in turn related to a rare-metal granite layer observed atop of the Panasqueira granite.

APA, Harvard, Vancouver, ISO, and other styles

11

Korshunova, V. A., E. D. Lodygin, M. V. Charykova, and S. N. Chukov. "Sorption interaction of gold and its pathfinder elements with humic acids of peat-podzolic soils." Theoretical and Applied Ecology, no. 3 (2020): 66–71. http://dx.doi.org/10.25750/1995-4301-2020-3-066-071.

Full text

APA, Harvard, Vancouver, ISO, and other styles

12

Whiting, M., and B. Humphreys. "Source-Finding for the Australian Square Kilometre Array Pathfinder." Publications of the Astronomical Society of Australia 29, no. 3 (2012): 371–81. http://dx.doi.org/10.1071/as12028.

Full text

Abstract:

AbstractThe Australian Square Kilometre Array Pathfinder (ASKAP) presents a number of challenges in the area of source finding and cataloguing. The data rates and image sizes are very large, and require automated processing in a high-performance computing environment. This requires development of new tools, that are able to operate in such an environment and can reliably handle large datasets. These tools must also be able to accommodate the different types of observations ASKAP will make: continuum imaging, spectral-line imaging, transient imaging. The ASKAP project has developed a source-finder known as selavy, built upon the duchamp source-finder. selavy incorporates a number of new features, which we describe here.Since distributed processing of large images and cubes will be essential, we describe the algorithms used to distribute the data, find an appropriate threshold and search to that threshold and form the final source catalogue. We describe the algorithm used to define a varying threshold that responds to the local, rather than global, noise conditions, and provide examples of its use. And we discuss the approach used to apply two-dimensional fits to detected sources, enabling more accurate parameterisation. These new features are compared for timing performance, where we show that their impact on the pipeline processing will be small, providing room for enhanced algorithms.We also discuss the development process for ASKAP source finding software. By the time of ASKAP operations, the ASKAP science community, through the Survey Science Projects, will have contributed important elements of the source finding pipeline, and the mechanisms in which this will be done are presented.

APA, Harvard, Vancouver, ISO, and other styles

13

A.M. Chekushkin, L.V. Filippenko, A.A. Lomov, Liu Dong, Shi Sheng-Cai, and V.P. Koshelets. "Optimization of fabrication processes for Nb, NbN, NbTiN films and high-quality tunnel junctions for terahertz receiving circuits." Technical Physics 92, no. 13 (2022): 2136. http://dx.doi.org/10.21883/tp.2022.13.52234.135-21.

Full text

Abstract:

This paper describes the optimization of the existing technology for the fabrication of superconducting films and high-quality tunnel junctions on a magnetron sputtering facility. To expand the frequency range to 1.1 THz and to obtain the limiting parameters of superconducting elements, the regimes of production of Nb, NbN, NbTiN films were optimized. These films are used to fabricate superconductor-insulator-superconductor Nb/Al--AlN/NbN tunnel junctions. Al and NbTiN films are required to create receiving elements at frequencies above 700 GHz (the cutoff frequency for niobium); such structures are being developed for the radio astronomy array receiver located in the Atacama Pathfinder Experiment telescope. Keywords: superconductivity, tunnel junctions, magnetron sputtering, thin films.

APA, Harvard, Vancouver, ISO, and other styles

14

Nyade, Praise K., Derek H. C. Wilton, Henry P. Longerich, Gary M. Thompson, and Paul McNeill. "Use of surficial geochemical methods to locate areas of buried uranium mineralization in the Jacque’s Lake area of the Central Mineral Belt, Labrador, Canada." Canadian Journal of Earth Sciences 50, no. 11 (November 2013): 1134–46. http://dx.doi.org/10.1139/cjes-2013-0032.

Full text

Abstract:

Surficial geochemical methods were applied to delineate zones of anomalous uranium and related element concentrations in areas overlain by an extensive blanket of glacial sediments and dense vegetation cover in the Jacque’s Lake area of the Central Mineral Belt, Labrador, Canada. The study involved sampling and analyses of vegetation including black spruce twigs and bark, Labrador tea shoots, and humus. Ash derived from the vegetation samples was analyzed using inductively coupled plasma – mass spectrometry (ICP–MS) following ignition at 450 °C, and humus was analyzed with delayed neutron counting (DNC) for a suite of 35 elements. B-horizon soil was analyzed using aqua regia digestion to investigate potential chemical signatures of bedrock mineralization at the surface. Uranium concentration in humus varied from 0.05 to 885 ppm. Zones exhibiting anomalous U responses were associated with areas proximal to anoxic peat and sphagnum bogs where mobile U species were sequestered. Uranium and pathfinder element (e.g., Pb, V, Sr, and Mo) concentrations were low in the <250 μm fraction of B-horizon soils. The soil geochemistry delineated bedrock U mineralization in areas with <15 cm of overburden and U concentration varied from 50 to 405 ppm. Biogeochemical signatures of the bedrock mineralization in black spruce twigs produced greater anomaly to background contrasts for U and pathfinder elements (e.g., Be, Ag, Pb, Ca, and Sb) and correlated more precisely with the detected radiometric U/Th anomaly than did those of soil and humus. Principal component analysis of spruce twig data discriminated three major components, including plant nutrients, ore-related elements, and a mobile species. Uranium concentration varied from below detection limit to 23 ppm U in black spruce bark and from below detection limit in ∼40% of samples to 18 ppm in Labrador tea stem.

APA, Harvard, Vancouver, ISO, and other styles

15

Nude, Prosper Mackenzie, John Mahfouz Asigri, Sandow Mark Yidana, Emmanuel Arhin, Gordon Foli, and Jacob Mawuko Kutu. "Identifying Pathfinder Elements for Gold in Multi-Element Soil Geochemical Data from the Wa-Lawra Belt, Northwest Ghana: A Multivariate Statistical Approach." International Journal of Geosciences 03, no. 01 (2012): 62–70. http://dx.doi.org/10.4236/ijg.2012.31008.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Graham, Garth E., Karen D. Kelley, John F. Slack, and Alan E. Koenig. "Trace elements in Zn–Pb–Ag deposits and related stream sediments, Brooks Range Alaska, with implications for Tl as a pathfinder element." Geochemistry: Exploration, Environment, Analysis 9, no. 1 (February 2009): 19–37. http://dx.doi.org/10.1144/1467-7873/08-177.

Full text

APA, Harvard, Vancouver, ISO, and other styles

17

Lindagato, Philemon, Yongjun Li, Gaoxue Yang, Fenghao Duan, and Zuopeng Wang. "Application of geostatistical analyst methods in discovering concealed gold and pathfinder elements as geochemical anomalies related to ore mineralisation." Geologos 24, no. 2 (August 1, 2018): 95–109. http://dx.doi.org/10.2478/logos-2018-0010.

Full text

Abstract:

Abstract The study area in the West Junggar Basin is known to be rich in hydrothermal gold deposits and occurrences, even though there has been minimum exploration in the area. It is here hypothesised that this area could host more gold deposits if mineral exploration methods were to be reinforced. This research is aimed at identifying geochemical anomalies of Au, and determining possible factors and conditions which facilitate the formation of anomalies by referring to As and Hg as gold pathfinders. Geostatistical analyst techniques have been applied to 9,852 stream sediments and bedrock data collected on a total surface of 1,280 km2 of West Junggar, Xinjiang (northwest China). The kriging interpolation and quantile-quantile plot methods, combined with statistical methods, successfully identified both Au and its pathfinders’ anomalies. In the present study, median was considered as background values (10.2 ppm for As, 9.13 ppb for Hg and 2.5 ppb for Au), whereas the 95th percentile were threshold values (28.03 ppm for As, 16.71 ppb for Hg and 8.2 ppb for Au) and values greater than thresholds are geochemical anomalies. Moreover, the high concentrations of these three discovered elements are caused primarily by hydrothermal ore mineralisation and are found to be controlled mainly by the Hatu and Sartohay faults of a northeast-southwesterly direction as well as their related secondary faults of variable orientation, which facilitate the easy flow of hydrothermal fluids towards the surface resulting in the formation of geochemical anomalies. Most of anomalies concentration of Au are found near the mining sites, which indicates that the formation of new Au anomalies is influenced by current or previous mining sites through geological or weathering processes. In addition, the low concentration of gold and its pathfinders found far from active gold mine or faults indicates that those anomalies are formed due to primary dispersion of hosting rock.

APA, Harvard, Vancouver, ISO, and other styles

18

Shirazy, Adel, Mansour Ziaii, Ardeshir Hezarkhani, and Timofey Timkin. "Geostatistical and Remote Sensing Studies to Identify High Metallogenic Potential Regions in the Kivi Area of Iran." Minerals 10, no. 10 (September 30, 2020): 869. http://dx.doi.org/10.3390/min10100869.

Full text

Abstract:

The Kivi area in the East Azerbaijan Province of Iran is one of the country’s highest-potential regions for metal element exploration. The primary goal herein was to process the data obtained from geochemical, geostatistical, and remote sensing tools (in the form of stream sediment samples and satellite images) to identify metallic mineralization anomalies in the region. After correcting the raw stream sediment geochemical data, single-variable statistical processing was performed, and Ti and Zn were identified as the elements with the highest degree of contrast. The relationship among these elements was further investigated using correlation and hierarchical clustering analyses. Principal component analysis was then applied to determine the principal components related to these elements, which were subsequently plotted on a regional geological map. Elements related to Ti and Zn were identified using threshold limits of anomalous samples determined via linear discriminant analysis. Lithological units and alteration patterns were detected through remote sensing investigations on Landsat-8 images. Stream sediment geochemical and remote sensing survey results identified anomalous areas of Ti and Zn in the eastern part of the study region. Our results indicate that Ti and Zn are good pathfinder elements for further exploratory investigation in this area.

APA, Harvard, Vancouver, ISO, and other styles

19

Mikšová, Dominika, Christopher Rieser, Peter Filzmoser, Simon Mose Thaarup, and Jeremie Melleton. "A Method to Identify Geochemical Mineralization on Linear Transects." Austrian Journal of Statistics 49, no. 4 (April 13, 2020): 89–98. http://dx.doi.org/10.17713/ajs.v49i4.1133.

Full text

Abstract:

Mineral exploration in biogeochemistry is related to the detection of anomalies in soil, which is driven by many factors and thus a complex problem. Mikšová, Rieser, and Filzmoser (2019b) have introduced a method for the identification of spatial patterns with increased element concentrations in samples along a linear sampling transect. This procedure is based on fitting Generalized Additive Models (GAMs) to the concentration data, and computing a curvature measure from the pairwise log-ratios of these fits. The higher the curvature, the more likely one or both elements of the pair indicate local mineralization. This method is applied on two geochemical data sets which have been collected specifically for the purpose of mineral exploration. The aim is to test the technique for its ability to identify pathfinder elements to detect mineralized zones, and to verify whether the method can indicate which sampling material is best suited for this purpose.

APA, Harvard, Vancouver, ISO, and other styles

20

Suliman Mostafa, Younis. "Litho chemical Prospecting for Gold Mineralization In Duweishat Mine Area-Northern Sudan." FES Journal of Engineering Sciences 3, no. 1 (November 6, 2008): 15. http://dx.doi.org/10.52981/fjes.v3i1.81.

Full text

Abstract:

The studied locality lies in North state of arid to semi-arid climate, where physical-mechanical weathering and denudation processes dominate. The lithostratgraphic sequence in geochronological order (from bottom to top) as high-grade gneisses, low-grade metasedments, serpentinized altrabasic (ophiolite complex) rocks, and younger granitoidal intrusions. Results which were obtained for Au and accompanying elements (Ag, Co, Cu, Pb, and Zn) were subjected to statistical analysis to reveral parameters such as (background value (Cb), coefficient of correlation, coefficient of variation, geochemical factors, productivities, and coefficient of dispersion). Sampling of residual soil was found to be effective in prospecting to reveal anomalous contents of chemical elements in the study area. Statistical methods interpretation of data proved to be effective and complement each other. The coefficients of correlation of Au with the accompanying elements in chip composite samples show values more reliable values for prospecting than those of the soil samples. Gold dispersion in the study area shows erratic behavior. The other mobile elements are dispersed around the mineralized quartz veins. The morphology of secondary dispersion halos of ore elements reflects more or less the morphology of the hidden ore bodies Coefficients of correlation when they are reliable can be used to define pathfinder to prospect for difficult gold. Geochemical factor can indicate horizon of mineralization and level of weathering.

APA, Harvard, Vancouver, ISO, and other styles

21

Korshunova, Vera A., Aleksandr V. Sergeev, and Marina V. Charykova. "Mobile forms of gold and pathfinder elements in secondary dispersion halo of Novye Pesky gold ore occurrence (South Karelia)." Vestnik of Saint Petersburg University. Earth Sciences 62, no. 1 (2017): 45–62. http://dx.doi.org/10.21638/11701/spbu07.2017.104.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Anand, R. R., R. M. Hough, C. Phang, and M. D. Norman. "The formation of ferruginous pisoliths and the mobility of gold and pathfinder elements in the Yilgarn Craton, Western Australia." Geochimica et Cosmochimica Acta 70, no. 18 (August 2006): A15. http://dx.doi.org/10.1016/j.gca.2006.06.044.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Scott, K. M. "The mineralogical distribution of pathfinder elements in gossans derived from dolomitic shale-hosted Pb-Zn deposits, northwest Queensland, Australia." Chemical Geology 64, no. 3-4 (October 1987): 295–306. http://dx.doi.org/10.1016/0009-2541(87)90009-x.

Full text

APA, Harvard, Vancouver, ISO, and other styles

24

Gazley, Michael F., Adam P. Martin, Rose E. Turnbull, Grace Frontin-Rollet, and Delia T. Strong. "Regional patterns in standardised and transformed pathfinder elements in soil related to orogenic-style mineralisation in southern New Zealand." Journal of Geochemical Exploration 217 (October 2020): 106593. http://dx.doi.org/10.1016/j.gexplo.2020.106593.

Full text

APA, Harvard, Vancouver, ISO, and other styles

25

Hung, Khuong The, Pham Nhu Sang, Nguyen Phuong, Vu Thai Linh, and Bui Viet Sang. "Statistical evaluation of the geochemical data for prospecting polymetallic mineralization in the Suoi Thau – Sang Than region, Northeast Vietnam." Geology, Geophysics and Environment 46, no. 4 (December 30, 2020): 285–99. http://dx.doi.org/10.7494/geol.2020.46.4.285.

Full text

Abstract:

In Northeast Vietnam, Suoi Thau-Sang Than is considered as a high potential area of polymetallic deposits. 1,720 geochemical samples were used to investigate polymetallic mineralization; thereby polymetallic ore occurrences in this study region were discovered and the statistical and multivariate analysis helps to define geochemical anomalies in some northeastern regions, namely Suoi Thau, Sang Than, and Ban Kep. The statistical method and cluster analysis of geochemical data indicate that the Cu, Pb, and Zn elements are good indicators, and most of them comply with the lognormal or gamma distribution. Based on the third-order threshold, the geochemical anomalies of the content of the Cu, Pb, and Zn elements reflect the concentration of copper forming ore bodies in the mineralized zone, and clearly show the concentration in three distinct zones. The trend surface analysis which was employed to determine spatial variations and relationships among these good indicator elements and anomalous areas revealed relative changes in the content of the indicator elements, and they can be considered as regular. Moreover, the goodness of fit obtained trend functions of Pb and Zn, and Cu elements is a third-degree trend surface model. These results indicate that the models can be useful in studying geochemical anomalies and analyzing the tendency of the concentration of indicator elements in the Suoi Thau-Sang Than region. Additionally, it is suggested that the statistical analysis shows a remarkable potential to use the bottom river sediments in the region to investigate polymetallic mineralization. Moreover, geochemical data can help to evaluate geochemical anomalies of the pathfinder elements and potential mineral mapping of the Suoi Thau-Sang Than region in Northeast Vietnam.

APA, Harvard, Vancouver, ISO, and other styles

26

Anand, R. R., R. M. Hough, W. Salama, M. F. Aspandiar, C. R. M. Butt, I. González-Álvarez, and V. Metelka. "Gold and pathfinder elements in ferricrete gold deposits of the Yilgarn Craton of Western Australia: A review with new concepts." Ore Geology Reviews 104 (January 2019): 294–355. http://dx.doi.org/10.1016/j.oregeorev.2018.11.003.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Kadel-Harder, Irene M., Paul G. Spry, Audrey L. McCombs, and Haozhe Zhang. "Identifying pathfinder elements for gold in bulk-rock geochemical data from the Cripple Creek Au–Te deposit: a statistical approach." Geochemistry: Exploration, Environment, Analysis 21, no. 1 (October 26, 2020): geochem2020–048. http://dx.doi.org/10.1144/geochem2020-048.

Full text

Abstract:

The Cripple Creek alkaline igneous rock-related, low-sulfidation epithermal gold telluride deposit, Colorado, is hosted in the 10 km wide Oligocene alkaline volcanic Cripple Creek diatreme in Proterozoic rocks. Gold occurs as native gold, Au-tellurides, and in the structure of arsenian pyrite, in potassically altered high-grade veins, and as disseminations in the host rocks.Correlation coefficients, principal component analysis, hierarchical cluster analysis and random forests were used to analyse major and trace element compositions of 995 rock samples primarily from low-grade gold mineralization in drill core from three currently operating pits (Wild Horse Extension, Globe Hill and Schist Island) in the northwestern part of the Cripple Creek diatreme. These methods suggest that Ag, As, Bi, Te and W are the best pathfinders to gold mineralization in low-grade disseminated ore. Although Mo correlates with gold in other studies and is spatially related to gold veins, molybdenite post-dated the formation of gold and is likely related to a late-stage porphyry overprint. These elements, in conjunction with mineralogical studies, indicate that tellurides, fluorite, quartz, carbonates, roscoelite, tennantite-tetrahedrite, pyrite, sphalerite, muscovite, monazite, bastnäsite and hübnerite serve as exploration guides to ore.

APA, Harvard, Vancouver, ISO, and other styles

28

Arhin, Emmanuel, Samson Boadi, and Millicent Captain Esoah. "Identifying pathfinder elements from termite mound samples for gold exploration in regolith complex terrain of the Lawra belt, NW Ghana." Journal of African Earth Sciences 109 (September 2015): 143–53. http://dx.doi.org/10.1016/j.jafrearsci.2015.05.022.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Harmon, Russell, Christopher Lawley, Jordan Watts, Cassady Harraden, Andrew Somers, and Richard Hark. "Laser-Induced Breakdown Spectroscopy—An Emerging Analytical Tool for Mineral Exploration." Minerals 9, no. 12 (November 20, 2019): 718. http://dx.doi.org/10.3390/min9120718.

Full text

Abstract:

The mineral exploration industry requires new methods and tools to address the challenges of declining mineral reserves and increasing discovery costs. Laser-induced breakdown spectroscopy (LIBS) represents an emerging geochemical tool for mineral exploration that can provide rapid, in situ, compositional analysis and high-resolution imaging in both laboratory and field and settings. We demonstrate through a review of previously published research and our new results how LIBS can be applied to qualitative element detection for geochemical fingerprinting, sample classification, and discrimination, as well as quantitative geochemical analysis, rock characterization by grain size analysis, and in situ geochemical imaging. LIBS can detect elements with low atomic number (i.e., light elements), some of which are important pathfinder elements for mineral exploration and/or are classified as critical commodities for emerging green technologies. LIBS data can be acquired in situ, facilitating the interpretation of geochemical data in a mineralogical context, which is important for unraveling the complex geological history of most ore systems. LIBS technology is available as a handheld analyzer, thus providing a field capability to acquire low-cost geochemical analyses in real time. As a consequence, LIBS has wide potential to be utilized in mineral exploration, prospect evaluation, and deposit exploitation quality control. LIBS is ideally suited for field exploration programs that would benefit from rapid chemical analysis under ambient environmental conditions.

APA, Harvard, Vancouver, ISO, and other styles

30

Rudakov, Kirill I., Andrey V. Khudchenko, Lyudmila V. Filippenko, Maxim E. Paramonov, Ronald Hesper, Daniele Aragão Ronsó da Costa Lima, Andrey M. Baryshev, and Valery P. Koshelets. "THz Range Low-Noise SIS Receivers for Space and Ground-Based Radio Astronomy." Applied Sciences 11, no. 21 (October 28, 2021): 10087. http://dx.doi.org/10.3390/app112110087.

Full text

Abstract:

We report on research in the field of low-noise receiving systems in the sub-terahertz (THz) range, carried out in recent years, aimed at developing receivers with quantum sensitivity for implementation in space and ground-based radio telescopes. Superconductor-Insulator-Superconductor (SIS) mixers based on high-quality tunnel junctions are the key elements of the most sensitive sub-THz heterodyne receivers. Motivations and physical background for technology improvement and optimization, as well as fabrication details, are described. This article presents the results of the SIS receiver developments for the 211–275 GHz and 790–950 GHz frequency ranges with a noise temperature in the double sideband (DSB) mode of approximTELY 20 K and 200 K, respectively. These designs and achievements are implemented in the development of the receiving systems for the Russian Space Agency mission “Millimetron”, and for the ground-based APEX (Atacama Pathfinder EXperiment) telescope.

APA, Harvard, Vancouver, ISO, and other styles

31

Anderson, Craig, George Heald, Shane O’Sullivan, John Bunton, Ettore Carretti, Aaron Chippendale, Jordan Collier, et al. "The Extraordinary Linear Polarisation Structure of the Southern Centaurus A Lobe Revealed by ASKAP." Galaxies 6, no. 4 (November 29, 2018): 127. http://dx.doi.org/10.3390/galaxies6040127.

Full text

Abstract:

We present observations of linear polarisation in the southern radio lobe of Centaurus A, conducted during commissioning of the Australian Square Kilometre Array Pathfinder (ASKAP) telescope. We used 16 antennas to observe a 30 square degree region in a single 12-h pointing over a 240 MHz band centred on 913 MHz. Our observations achieve an angular resolution of 26 × 33 arcseconds (480 parsecs), a maximum recoverable angular scale of 30 arcminutes, and a full-band sensitivity of 85 μ Jy beam − 1 . The resulting maps of polarisation and Faraday rotation are amongst the most detailed ever made for radio lobes, with order 10 5 resolution elements covering the source. We describe several as-yet unreported observational features of the lobe, including its detailed peak Faraday depth structure, and intricate networks of depolarised filaments. These results demonstrate the exciting capabilities of ASKAP for widefield radio polarimetry.

APA, Harvard, Vancouver, ISO, and other styles

32

McClenaghan, Beth, Allen Seaman, Michael Parkhill, and Antonius Pronk. "Till geochemical signatures associated with the Sisson W-Mo deposit, New Brunswick, Canada." Atlantic Geology 50 (September 24, 2014): 116. http://dx.doi.org/10.4138/atlgeol.2014.008.

Full text

Abstract:

A till composition study was carried out around the Sisson W-Mo deposit, New Brunswick, Canada, one of the largest W deposits in the world, to test modern analytical methods for W in till and document glacial dispersal from a significant W source. The <0.063 mm fraction of till defines glacial dispersal down ice of the deposit and use of this fraction is recommended for W-Mo exploration in the region. Metal-rich till overlying the deposit contains up to 816 ppm W and 63 ppm Mo. One km down ice, till contains 75 ppm W and 8 ppm Mo, and till in background areas contains a maximum of 7 ppm W, and 2 ppm Mo. Indicator elements for the deposit include W and Mo, and pathfinder elements include Ag, As, Bi, Cd, Cu, In, Pb, Te, and Zn. This list of elements is more extensive than previously identified for the Sisson deposit or identified in other published till geochemical studies because of the polymetallic nature of the Sisson deposit and the broad suite of elements that can now be determined using modern analytical techniques. Lithium meta/tetraborate fusion inductively coupled plasma-mass spectrometry was used to determine the total concentration of W in till and is a fast and cost effective method as compared to those reported in the older literature. Glacial dispersal of W and Mo from the Sisson deposit is detectable at a regional scale at least 14 km down ice (southeast) using surface till sampling. A 2 km till sample spacing should be sufficient to detect glacial dispersal from a W-Mo deposit of this size.

APA, Harvard, Vancouver, ISO, and other styles

33

Henne, Anicia, Nathan Reid, Robert L. Thorne, Samuel C. Spinks, Tenten Pinchand, and Alistair White. "Multi-Media Geochemical Exploration in the Critical Zone: A Case Study over the Prairie and Wolf Zn–Pb Deposits, Capricorn Orogen, Western Australia." Minerals 11, no. 11 (October 22, 2021): 1174. http://dx.doi.org/10.3390/min11111174.

Full text

Abstract:

In this study, we compared traditional lithochemical sample media (soil) with hydrochemical (groundwater), biogeochemical (plant matter of mulga and spinifex), and other near-surface sample media (ferro-manganese crust), in a case study applied to mineral exploration in weathered terrain, through the critical zone at the fault-hosted Prairie and Wolf Zn–Pb (Ag) deposits in Western Australia. We used multi-element geochemistry analyses to spatially identify geochemical anomalies in samples over known mineralization, and investigated metal dispersion processes. In all near-surface sample media, high concentrations of the metals of interest (Zn, Pb, Ag) coincided with samples proximal to the mineralization at depth. However, the lateral dispersion of these elements differed from regional (several km; groundwater) to local (several 100′s of meters; solid sample media) scales. Zinc in spinifex leaves over the Prairie and Wolf deposits exceeded the total concentrations in all other sample media, while the metal concentrations in mulga phyllodes were not as pronounced, except for Ag, which exceeded the concentrations in all other sample media. These observations indicate potential preferential metal-specific uptake by different media. Pathfinder elements in vegetation and groundwater samples also indicated the Prairie Downs fault zone at the regional (groundwater) and local (vegetation) scale, and are, therefore, potentially useful tools to trace fault systems that host structurally controlled, hydrothermal Zn–Pb mineralization.

APA, Harvard, Vancouver, ISO, and other styles

34

Dunn, C. E., and A. B. Christie. "Tree ferns and tea trees in biogeochemical exploration for epithermal Au and Ag in New Zealand." Geochemistry: Exploration, Environment, Analysis 20, no. 3 (July 25, 2019): 299–314. http://dx.doi.org/10.1144/geochem2019-047.

Full text

Abstract:

Biogeochemical orientation surveys were undertaken at low sulphidation epithermal Au–Ag occurrences in the Hauraki Goldfield–Coromandel Volcanic Zone and the Taupo Volcanic Zone, and at the Waiotapu active geothermal area in the Taupo Volcanic Zone. Several plant species were sampled, including the foliage of tree ferns and tea trees. The ferns – silver fern (ponga), rough tree fern (wheki) and black tree fern (mamaku) – were ubiquitous and were the easiest species to sample, although tea tree was the dominant genus at Waiotapu. At the Waiotapu geothermal area, significantly higher concentrations of Ag, Au, Sb, As, Cs and Rb were present in samples close to Champagne Pool than elsewhere, confirming its location as the main outflow source of Au, Ag and their pathfinder elements. The fern survey areas at Luck at Last mine, Pine Sinter and Ohui in the Coromandel Volcanic Zone each exhibited biogeochemical anomalies, which successfully highlighted most of the known quartz veins and provided additional anomalies for further investigation. Rough tree fern was the most common species at Goldmine Hill, Puhipuhi (Taupo Volcanic Zone). Although this species absorbs lower concentrations of many elements than the silver fern, the spatial distribution of elements is of greater significance than their absolute concentrations. The highest Au, Ag, As and Al concentrations occurred in samples from a ridge extending WNW from Goldmine Hill. Sb and Bi were at anomalous levels in an area peripheral to the precious metal anomalies, indicating the potential zonation of elements distal from the Au and Ag deposits.Supplementary material: The full datasets on the fern and tea tree chemistry, including quality assurance/quality control and multi-element plots, are available free of charge through the GNS Science website (search for Dunn) at http://shop.gns.cri.nz/publications/science-reports/.

APA, Harvard, Vancouver, ISO, and other styles

35

Hanapi, Nurul Liyana, Sabarinah Sh Ahmad, and Azli Abd Razak. "Evaluation of Escape Route Design in Public Multi-Storey Housing in Malaysia for Elderly Occupants." Environment-Behaviour Proceedings Journal 5, SI2 (December 27, 2020): 25–31. http://dx.doi.org/10.21834/ebpj.v5isi2.2521.

Full text

Abstract:

Public multi-storey residential buildings in Malaysia are dependent on the passive design approach to ensure maximum safety during an emergency. Elements of escape route design include corridors, exits and staircases. This paper evaluates the escape route distance and duration for the elderly to evacuate the building to safety using Pathfinder simulations. The results show that the staircase has a significant contribution towards providing fast evacuation. Meanwhile, varying the width of the exit doors and corridors had minimal impact on evacuation. On average, the elderlies took longer to evacuate due to their slow speed of movement and limited physical capability. Keywords: Multi-Storey, Escape Route Design, Evacuation, Simulation eISSN: 2398-4287 © 2020. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open access article under the CC BYNC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia. DOI: https://doi.org/110.21834/ebpj.v5iSI2.2521.

APA, Harvard, Vancouver, ISO, and other styles

36

Mira, Hamed Ibrahim, Hussein Kamal Hussein, Sameh Zakaria Tawfik, and Neveen Salah Abed. "Stream Sediments Geochemical Exploration in Wadi El Reddah area, Northeastern Desert, Egypt." Mediterranean Journal of Chemistry 10, no. 8 (November 2, 2020): 809. http://dx.doi.org/10.13171/mjc10802011021539st.

Full text

Abstract:

Wadi El Reddah representing a semi-closed basin, extends in the N-S direction. It has only one outlet at the northern tip while the wadi collects floodwater from internal tributaries along wall rocks. The present study discusses the relationship between geology and geochemistry data to detect anomalous radioactive locations. The geochemical maps show the mineralization areas with abnormal rare metal contents. This led to two uranium occurrences (GXXIII and GXXIV) at Gabal Gattar in the perthitic leucogranite. At Wadi El Reddah, high contents of pathfinder elements (REE, Y, Zn, Nb and As) were discovered at the southern and eastern boundaries. This may be attributed to the presence of alkali feldspar granite at Gabal Gattar at the upstream of Wadi El Reddah and also to the sharp contact between Gabal Gattar and Hammamat Sedimentary rocks. A strong positive correlation coefficient between Fe2Ot and or Al2O3 with Zr, Hf, Nb, Ta, REE, U, Rb, and Th reflects their association with thematization processes.

APA, Harvard, Vancouver, ISO, and other styles

37

Çoban, Hakan. "Geochemistry of metamorphic-hosted iron ore deposit and associated silica caps in Arıdağ mountain, Bitlis, Eastern Anatolia: preliminary records and pathfinder elements for hydrothermal origin." Bitlis Eren University Journal of Science and Technology 9, no. 2 (December 27, 2019): 67–71. http://dx.doi.org/10.17678/beuscitech.609954.

Full text

APA, Harvard, Vancouver, ISO, and other styles

38

Warren, Michael R., Jacob J. Hanley, Doreen E. Ames, and Simon E. Jackson. "The Ni–Cr–Cu content of biotite as pathfinder elements for magmatic sulfide exploration associated with mafic units of the Sudbury Igneous Complex, Ontario, Canada." Journal of Geochemical Exploration 153 (June 2015): 11–29. http://dx.doi.org/10.1016/j.gexplo.2015.02.010.

Full text

APA, Harvard, Vancouver, ISO, and other styles

39

Courtney-Davies, Ciobanu, Verdugo-Ihl, Slattery, Cook, Dmitrijeva, Keyser, et al. "Zircon at the Nanoscale Records Metasomatic Processes Leading to Large Magmatic–Hydrothermal Ore Systems." Minerals 9, no. 6 (June 16, 2019): 364. http://dx.doi.org/10.3390/min9060364.

Full text

Abstract:

The petrography and geochemistry of zircon offers an exciting opportunity to better understand the genesis of, as well as identify pathfinders for, large magmatic–hydrothermal ore systems. Electron probe microanalysis, laser ablation inductively coupled plasma mass spectrometry, high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) imaging, and energy-dispersive X-ray spectrometry STEM mapping/spot analysis were combined to characterize Proterozoic granitic zircon in the eastern Gawler Craton, South Australia. Granites from the ~1.85 Ga Donington Suite and ~1.6 Ga Hiltaba Suite were selected from locations that are either mineralized or not, with the same style of iron-oxide copper gold (IOCG) mineralization. Although Donington Suite granites are host to mineralization in several prospects, only Hiltaba Suite granites are considered “fertile” in that their emplacement at ~1.6 Ga is associated with generation of one of the best metal-endowed IOCG provinces on Earth. Crystal oscillatory zoning with respect to non-formula elements, notably Fe and Cl, are textural and chemical features preserved in zircon, with no evidence for U or Pb accumulation relating to amorphization effects. Bands with Fe and Ca show mottling with respect to chloro–hydroxy–zircon nanoprecipitates. Lattice defects occur along fractures crosscutting such nanoprecipitates indicating fluid infiltration post-mottling. Lattice stretching and screw dislocations leading to expansion of the zircon structure are the only nanoscale structures attributable to self-induced irradiation damage. These features increase in abundance in zircons from granites hosting IOCG mineralization, including from the world-class Olympic Dam Cu–U–Au–Ag deposit. The nano- to micron-scale features documented reflect interaction between magmatic zircon and corrosive Fe–Cl-bearing fluids in an initial metasomatic event that follows magmatic crystallization and immediately precedes deposition of IOCG mineralization. Quantification of α-decay damage that could relate zircon alteration to the first percolation point in zircon gives ~100 Ma, a time interval that cannot be reconciled with the 2–4 Ma period between magmatic crystallization and onset of hydrothermal fluid flow. Crystal oscillatory zoning and nanoprecipitate mottling in zircon intensify with proximity to mineralization and represent a potential pathfinder to locate fertile granites associated with Cu–Au mineralization.

APA, Harvard, Vancouver, ISO, and other styles

40

Byrne, Kevin, Guillaume Lesage, Sarah A. Gleeson, Stephen J. Piercey, Philip Lypaczewski, and Kurt Kyser. "Linking Mineralogy to Lithogeochemistry in the Highland Valley Copper District: Implications for Porphyry Copper Footprints." Economic Geology 115, no. 4 (June 1, 2020): 871–901. http://dx.doi.org/10.5382/econgeo.4733.

Full text

Abstract:

Abstract The Highland Valley Copper porphyry deposits, hosted in the Late Triassic Guichon Creek batholith in the Canadian Cordillera, are unusual in that some of them formed at depths of at least 4 to 5 km in cogenetic host rocks. Enrichments in ore and pathfinder elements are generally limited to a few hundred meters beyond the pit areas, and the peripheral alteration is restricted to narrow (1–3 cm) halos around a low density of prehnite and/or epidote veinlets. It is, therefore, challenging to recognize the alteration footprint peripheral to the porphyry Cu systems. Here, we document a workflow to maximize the use of lithogeochemical data in measuring changes in mineralogy and material transfer related to porphyry formation by linking whole-rock analyses to observed alteration mineralogy at the hand specimen and deposit scale. Alteration facies and domains were determined from mapping, feldspar staining, and shortwave infrared imaging and include (1) K-feldspar halos (potassic alteration), (2) epidote veins with K-feldspar–destructive albite halos (sodic-calcic alteration), (3) quartz and coarse-grained muscovite veins and halos and fine-grained white-mica–chlorite veins and halos (white-mica–chlorite alteration), and two subfacies of propylitic alteration comprising (4) prehnite veinlets with white-mica–chlorite-prehnite halos, and (5) veins of epidote ± prehnite with halos of chlorite and patchy K-feldspar. Well-developed, feldspar-destructive, white-mica alteration is indicated by (2[Ca-C] + N + K)/Al values <0.85, depletion in CaO and Na2O, enrichment in K2O, and localized SiO2 addition and is spatially limited to within ~200 m of porphyry Cu mineralization. Localized K2O, Fe2O3, and depletion in Cu, and some enrichment in Na2O and CaO, occurs in sodic-calcic domains that form a large (~34 km2) nonconcentric footprint outboard of well-mineralized and proximal zones enriched in K. Water and magmatic CO2-rich propylitic and sodic-calcic–altered rocks form the largest lithogeochemical footprint to the mineralization in the Highland Valley Copper district (~60 km2). Calcite in the footprint is interpreted to have formed via phase separation of CO2 from a late-stage magmatic volatile phase. Several observations from this study are transferable to other porphyry systems and have implications for porphyry Cu exploration. Feldspar staining and shortwave infrared imaging highlight weak and cryptic alteration that did not cause sufficient material transfer to be confidently distinguished from protolith lithogeochemical compositions. Prehnite can be a key mineral phase in propylitic alteration related to porphyry genesis, and its presence can be predicted based on host-rock composition. Sodic-calcic alteration depletes the protolith in Fe (and magnetite) and, therefore, will impact petrophysical and geophysical characteristics of the system. Whole-rock loss on ignition and C and S analyses can be used to map enrichment in water and CO2 in altered rocks, and together these form a large porphyry footprint that extends beyond domains of enrichment in ore and pathfinder elements and of pronounced alkali metasomatism.

APA, Harvard, Vancouver, ISO, and other styles

41

Rissmann, C. W. F., M. I. Leybourne, C. Benn, J. A. Kidder, and L. K. Pearson. "Comparison of groundwater composition from the Monturaqui and Punta Negra Basins, northern Chile: implications for porphyry copper exploration." Geochemistry: Exploration, Environment, Analysis 22, no. 2 (February 14, 2022): geochem2021–056. http://dx.doi.org/10.1144/geochem2021-056.

Full text

Abstract:

Groundwaters recovered from the Salar de Punta Negra and Monturaqui basins in the Atacama Desert of northern Chile exhibit distinctly different isotopic, major, trace, and porphyry copper elemental compositions related to contrasting morphostructural, geochemical, and hydrodynamic settings. Comparison of these distinct groundwater signatures with groundwaters from known porphyry copper deposits (Salar de Hamburgo and Spence Deposit), can be used to determine if either basin might be prospective for porphyry copper mineralization. Groundwaters within the Punta Negra Basin exhibit geochemical characteristics consistent with other closed basin settings throughout the arid Andes. Elemental and isotopic compositions within the Punta Negra Basin reflect closed basin evaporitic processes consistent with the hyperarid, volcanic setting of the central Andes. Pathfinder metals and isotopic compositions are not consistent with porphyry copper type mineralization as described for groundwaters within the Salar de Hamburgo Basin, and the Spence Deposit. Within the Monturaqui Basin the geochemical composition of groundwaters are characteristic of diffuse hydrothermal activity. Sulfur isotopic composition within the waters of the northern Monturaqui Basin exhibit δ34SCDT isotopic signatures that fall within the range for sulfide mineralization as reported for groundwaters in and around the Spence Deposit and the Salar de Hamburgo. However, porphyry copper related elements within the Monturaqui Basin are impoverished relative to groundwaters of the Spence and Escondida Deposit. Such impoverishment in porphyry related elements, taken in conjunction with enriched δ13CPDB compositions, elevated groundwater temperatures, groundwater compositions dominated by HCO3, SO4, and Si, and the proximity of the Monturaqui Basin to the current magmatic arc are consistent with a volcanic hydrothermal origin. In summary, the groundwater geochemistry of the Monturaqui and Punta Negra Basins are not indicative of porphyry copper-type mineralization.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

APA, Harvard, Vancouver, ISO, and other styles

42

Baker, Michael J., Jamie J. Wilkinson, Clara C. Wilkinson, David R. Cooke, and Tim Ireland. "Epidote Trace Element Chemistry as an Exploration Tool in the Collahuasi District, Northern Chile." Economic Geology 115, no. 4 (June 1, 2020): 749–70. http://dx.doi.org/10.5382/econgeo.4739.

Full text

Abstract:

Abstract The Collahuasi district of northern Chile hosts several late Eocene-early Oligocene world-class porphyry Cu-Mo deposits, including Rosario, Ujina, and Quebrada Blanca deposits, and associated high-sulfidation epithermal mineralization at La Grande. Mineralization is hosted by intermediate to felsic intrusive and volcanic rocks of the upper Paleozoic to Lower Triassic Collahuasi Group, which experienced lower greenschist facies regional metamorphism prior to mineralization. Extensive hydrothermal alteration zones surround the porphyry and epithermal deposits, associated with hypogene ore-forming processes. However, outside of the observed sulfide halo the limits of geochemical anomalism associated with mineralization are difficult to define due to mineralogical similarities between weak, distal propylitic alteration and regional metamorphism affecting the host rocks. Recent advancements in laser ablation-inductively coupled plasma-mass spectrometry analysis of epidote from hydrothermal alteration zones around porphyry and skarn deposits have shown that low-level hypogene geochemical anomalies can be detected at distances farther from the center of mineralization than by conventional rock chip sampling. Selective analysis of propylitic epidote from the Collahuasi district indicates that anomalous concentrations of distal pathfinder elements in epidote, including As (>50 ppm), Sb (>25 ppm), Pb (>100 ppm), and Mn (>5,000 ppm), were detectable 1.5 to 4.0 km from deposit centers. Significantly, the concentrations of these trace elements in epidote were obtained from samples that contained whole-rock concentrations of <25 ppm As, <2 ppm Sb, <100 ppm Pb, and <5,000 ppm Mn. Systematic increases in Cu, Mo, and Sn concentrations in epidote near deposit centers, and corresponding decreasing As, Sb and Pb concentrations, also provide effective tools for assessing the fertility and locating the centers of porphyry mineralization. In addition, anomalous concentrations in epidote of Cu (up to 1 wt %) and Zn (up to 6,000 ppm) effectively discriminate epidote associated with high-sulfidation epithermal veins in the Collahuasi district (e.g., La Grande, Poderosa-Rosario) from alteration associated with porphyry mineralization.

APA, Harvard, Vancouver, ISO, and other styles

43

Ibrahim, Mohammed, Alexander Kotelnikov, Pavel Podolko, and Elena Kotelnikova. "Remote sensing data for Geological mapping and gold prospecting of Inteet area, northern Sudan." E3S Web of Conferences 258 (2021): 03009. http://dx.doi.org/10.1051/e3sconf/202125803009.

Full text

Abstract:

The mineral exploration has improved in the last decades, today there are different methods of remote exploration, that are applied in mining industry worldwide, helping to discover ore minerals deposits in zones that have not access to them. The study area of this article is located about 400 km from Khartoum, characterized by low reliefs covered by sand and gravely sand. The study wants to carry out the geological mapping and the prospective zones using remote sensing and GIS techniques. Sudan is characterized by geological formations over inaccessible areas, in that way the remote sensing technique has a great value in these conditions, saving time and money. The used methodology has been divided into three phases: Pre-field office work, field work and post-field work. The processing of the satellite images includes color band composites, in order to obtain the lithological and geological features, the different types of rocks were defined by a different color. Obtaining the following rock types: High-grade gneisses and migmatites described to comprise the basement complex, ophiolitic mafic-ultramafic rocks that appear in the northern and southern sides of the area, metasediments that cover most of the study area, syn-orogenic intrusions that cut the older mafic-ultramafic units and the metavolcanosedimentary sequences, post-orogenic intrusions and gold mineralization. Based on the image analysis results of Landsat 8 OLI, 32 ore samples were collected to analysis gold and pathfinder elements obtaining high anomalies results for Au, Ag, Cu, Zn, Pb and Fe.

APA, Harvard, Vancouver, ISO, and other styles

44

Zhou, Yan, Tiangang Wang, Feipeng Fan, Shizhong Chen, Weimin Guo, Guangfu Xing, Jiandong Sun, and Fan Xiao. "Advances on Exploration Indicators of Mineral VNIR-SWIR Spectroscopy and Chemistry: A Review." Minerals 12, no. 8 (July 28, 2022): 958. http://dx.doi.org/10.3390/min12080958.

Full text

Abstract:

Establishing exploration vectors to infer the properties of ore-forming fluids, locate blind ore bodies with the aid of visible to near-infrared (VNIR) and short-wave infrared (SWIR) spectroscopy, and infer the chemistry of minerals, is a new research interest for economic geology. Common alterations and clay minerals, including sericite, chlorite, epidote, alunite, kaolinite, tourmaline, etc., are ideal objects for the study of exploration indicators due to their sensitivity to variations in the nature of hydrothermal fluid. The diagnostic spectral feature and chemistry vary spatially and systematically with physicochemical change. VNIR spectroscopy can characterize the REE-bearing clay minerals directly. Obtaining spectral or chemical parameters with the aid of VNIR-SWIR spectroscopy, electron probe micro-analyzer (EPMA) or laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) can help to establish exploration vectors. This paper systematically summarizes recent advances in mineral exploration indicators (MEIs) of VNIR-SWIR spectroscopy and chemistry, and compares them in different regions or deposits. We found that some MEI spatial variation trends are random, even the same type of deposit can show an opposite trend. The controlling factors that limit the application of the established MEIs are vague. Conducting further research on petrology and mineralogy with the aids of observation under microscopy, X-ray diffraction (XRD), TESCAN Integrated Mineral Analyzer (TIMA), and EPMA are suggested to discover alteration mineral assemblage, alteration stages, and behaviors of “the pathfinder elements” related to mineralization. Based on the above research, the physicochemical properties of ore-forming fluids and their control over MEIs can be inferred. Refining the theoretical basis is critical to understanding and popularization of spectral and chemical MEIs.

APA, Harvard, Vancouver, ISO, and other styles

45

Bolin, Brock J., and Thomas S. Moon. "Sulfide detection in drill core from the Stillwater Complex using visible/near‐infrared imaging spectroscopy." GEOPHYSICS 68, no. 5 (September 2003): 1561–68. http://dx.doi.org/10.1190/1.1620630.

Full text

Abstract:

This feasibility study examines the potential of imaging spectroscopy to estimate sulfide percentage in drill core from the Stillwater Complex, Montana. The Stillwater Complex is a layered mafic to ultramafic intrusion hosting ore‐grade platinum group elements within the zone known as the JM Reef. Stillwater Mine geologists indirectly infer the platinum/palladium grade by the presence and abundance of sulfide minerals. In order to discriminate between waste and ore rock, geologists visually inspect the core and working faces for minerals such as chalcopyrite, pentlandite, and pyrrhotite. Iron sulfide minerals have a strong ultraviolet absorption that blends into the blue portion of the visible region and produces their yellow luster. The spectral differences between these pathfinder minerals and the accessory minerals are sufficiently distinct to allow classification of this mineralogy using imaging spectroscopy even in the absence of a particular absorption feature. Five different sections of split core from the JM Reef were chosen for their representative mineralogical character. The surface of each sample was scanned with Montana Tech's prototype Airborne and Laboratory Imaging Spectrometer (ALIS) and the images were analyzed for sulfides. For validation, the amount of sulfides was independently determined visually with counting grids. The imaging spectrometer results correlate well with the point‐count percentage, although all five samples consistently fall below the point‐count average. This underestimation is possibly due to metal ion substitution, linear mixing at mineral boundaries, or anisotropic scattering due to the high spatial resolution of the spectrometer. The success of this experiment suggests possible machine vision applications in future mining operations, such as automation of core logging and downhole instrumentation.

APA, Harvard, Vancouver, ISO, and other styles

46

Valentino, Marissa, T. Kurt Kyser, Matthew I. Leybourne, Tom Kotzer, David Quirt, Philip Lypaczewski, Daniel Layton-Matthews, and Nicholas Joyce. "Mineralogy and petrogenesis of fracture coatings in Athabasca Group sandstones from the McArthur River uranium deposit." Canadian Mineralogist 59, no. 5 (September 1, 2021): 1021–47. http://dx.doi.org/10.3749/canmin.2000098.

Full text

Abstract:

ABSTRACT The McArthur River unconformity-related uranium deposit, located in the Athabasca Basin of Saskatchewan, Canada, is structurally hosted near the unconformity between Archean to Paleoproterozoic metasedimentary basement and the Proterozoic Athabasca Group sandstones. In this study, the mineralogy and geochemistry of fracture materials within the entire ca. 550 m thickness of the Athabasca Group sandstones and the metasedimentary (host) rocks from the McArthur River area were used to determine the paragenetic sequence and origin of minerals in and near the fractures. Our work sought to determine if the host minerals record elements associated with the uranium deposit at depth and if they could be used to guide exploration (vectoring). Fracture orientations indicate that most are moderately dipping (<50°) and provided permeable pathways for fluid movement within the basin, from below, and through the overlying sedimentary rocks. Many of the fractures and adjacent wall rocks record evidence of multiple distinct fluid events. Seven types of fracture fillings were identified from drill core intersecting the Athabasca Basin and present distinct colors, mineralogy, and chemical features. Brown (Type 1) and pink (Type 7) fractures host paragenetically late botryoidal goethite, Mn oxide minerals, and poorly crystallized kaolinite that formed from relatively recent low-temperature meteoric fluids, as indicated by poor crystallinity and low δ2H values of –198 to –115‰. These minerals variably replaced higher temperature minerals that are rarely preserved on the fractures or in wall rock near the fractures. Hydrothermal alteration associated with the mineralizing system at ca. 200 °C is recorded in assemblages of dickite, well-crystallized kaolinite, and spherulitic dravite in some white and yellow (Type 2) and white (Type 3) fractures, as reflected by the crystal habits and variable δ2H values of –85 to –44‰. Fibrous goethite in white and yellow (Type 2) and black and orange (Type 5) fractures and microfibrous Mn oxy-hydroxide minerals in black (Type 4) fractures also crystallized from hydrothermal fluids, but at temperatures less than 200 °C. White and yellow fractures (Type 2) containing fibrous goethite reflect fracture networks indicative of hydrothermal fluids associated with the mineralizing system during primary dispersion of pathfinder elements and therefore extend the deposit footprint. Brown (Type 1) and pink (Type 7) fractures have low δ2H values in botryoidal goethite and poorly crystallized kaolinite and are indicative of the movement of meteoric waters. Secondary dispersion of elements from the deposit to the surface on some fractures is evidence that fractures are pathways for element migration from the deposit to the surface, over distances exceeding ∼500 m.

APA, Harvard, Vancouver, ISO, and other styles

47

TURIMUMAHORO, Denis, Niels HULSBOSCH, Louis NAHIMANA, Stijn DEWAELE, and Philippe MUCHEZ. "Géochimie des muscovites comme indicateur du fractionnement des pegmatites de la région de Kabarore-Mparamirundi (nord-ouest du Burundi, Afrique centrale) [Geochemical signature of muscovites as pathfinder for fractionation of pegmatites in the Kabarore-Mparamirundi area (northwestern Burundi, Central Africa)]." Geologica Belgica 23, no. 1-2 (May 20, 2020): 53–67. http://dx.doi.org/10.20341/gb.2020.005.

Full text

Abstract:

The Kabarore-Mparamirundi area hosts numerous pegmatites spatiotemporally related to leucogranites dated at 986 ± 10 Ma in Karagwe-Ankole belt. The deposits are intensively exploited for columbite-tantalite and cassiterite. Alkali metals in muscovite (Rb 370–7590 ppm, Cs 8–1470 ppm) are modeled by Rayleigh fractional crystallization from a parental leucogranitic composition (K 4.1 wt%, Rb 321 ppm and Cs 9 ppm). The power law declining behavior of the ratio K/Rb versus Cs indicates the Rayleigh fractional crystallization as the main process of differentiation of the various pegmatite facies. Moreover, the continuous trend from granite to the most evolved, exploited pegmatites demonstrates a co-genetic link among them. The fractionation model shows that unmined and abandoned pegmatites are less fractionated (less than 94% of fractionation) while mined pegmatites are highly fractionated and constitute fractionated products of more than 94% of the initial leucogranite composition. The Rb, Cs, Ta, Sn and Li elements in muscovite can be used as a valuable tool in the exploration of fertile and sterile pegmatites in this area.

APA, Harvard, Vancouver, ISO, and other styles

48

Knaack, Derek, Gillian Ivey, Caitlyn MacPhee, Jordan Peterzon, Liam Price, Matthew Williams, and Matthew I. Leybourne. "The effect of filtration size on the geochemistry of groundwater samples from a massive sulfide deposit at the Bathurst Mining Camp, New Brunswick, Canada." Geochemistry: Exploration, Environment, Analysis 21, no. 4 (October 12, 2021): geochem2021–057. http://dx.doi.org/10.1144/geochem2021-057.

Full text

Abstract:

In hydrogeochemical studies, samples are commonly filtered to limit the fraction of analyte that is adsorbed or structurally bound to suspended particles, ensuring that only the dissolved fraction is analysed, and thereby reducing analytical bias during measurement. The standard filter size that has been adopted is 0.45 μm; however, ultrafiltration can be used to remove colloidal particles two orders of magnitude smaller. In the following, we investigate the effect that standard filtration (0.45 μm) and ultrafiltration (0.004 μm) have on the hydrogeochemistry of groundwaters from a volcanogenic massive sulfide (VMS) deposit at the Bathurst Mining Camp, New Brunswick, Canada. Groundwater samples were collected from six monitoring wells at the Nigadoo Mine tailings facility, and major and trace geochemistry were determined using a combination of inductively coupled plasma optical emission spectrometry, inductively coupled plasma mass spectrometry and ion chromatography. Waters at the Nigadoo deposit are generally enriched in Ca and SO4, relative to other major cations and anions. Some element contents – including those associated with VMS deposits – differ depending on the filtration technique used (e.g. As, Fe, Pb, rare earth elements and yttrium (REY)), some are equally affected by both techniques (e.g. Cu, Ni, Zn), and some are unaffected by filtration (e.g. Ba, Ca, Mn, Cl−). Shale-normalized REY anomalies (CeSN/CeSN*, EuSN/EuSN* and YSN/HoSN) and overall patterns can differ greatly (e.g. changing the sign of the anomaly) depending on the filtration technique used. We observe previously undocumented and, at this time, unexplainable fractionation of Ho and Yb (non-redox sensitive REY, unaffected by the tetrad effect) in unfiltered waters from the Nigadoo deposit. Differences in groundwater geochemistry induced by filtration technique can result in false positive and negative anomalies during environmental and exploration projects and must therefore be carefully considered. At the Nigadoo site, oxidation of sulfide minerals can occur, resulting in the formation of relatively unstable oxide minerals. Away from the tailings, where carbonate minerals are scarce and can no longer act as a pH buffer, the unstable oxide minerals break down and release metals and metalloids into the surrounding environment. The filtration methods used in this study can provide insight into where the specific metals and metalloids are hosted and how they are likely to behave under different redox conditions. Because VMS deposit pathfinder elements are enriched in unfiltered water, and differ by degree of filtration, geochemical analysis of the filtride material may also make an effective exploration tool.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

APA, Harvard, Vancouver, ISO, and other styles

49

Kuo, Chao-Lin. "Toward a 10,000-element B-Mode Experiment." Proceedings of the International Astronomical Union 8, S288 (August 2012): 80–83. http://dx.doi.org/10.1017/s1743921312016717.

Full text

Abstract:

AbstractIn this paper, we introduce two compact, large-throughput CMB polarimeter designs (POLAR1 and BICEP3). These pathfinder experiments will pave the way for a comprehensive multi-frequency South Pole B-mode survey that, when jointly analyzed with arcminute-scale polarization data, can conclusively answer the question whether there is an appreciable fraction (>1%) of the primordial perturbations in the form of tensor modes (gravitational waves).

APA, Harvard, Vancouver, ISO, and other styles

50

Beyer, Steve R., Kurt Kyser, Tom G. Kotzer, Kevin Ansdell, and David Quirt. "Exploration geochemistry of surficial media over the high-grade McArthur River uranium deposit, Saskatchewan, Canada." Canadian Mineralogist 59, no. 5 (September 1, 2021): 913–45. http://dx.doi.org/10.3749/canmin.2000081.

Full text

Abstract:

ABSTRACT An orientation survey using surficial media was performed over the high-grade McArthur River unconformity-related U deposit (Saskatchewan, Canada) to test whether or not secondary dispersion of elements related to the ore body or alteration zone can be detected at the surface more than 500 m above the deposit. Organic-rich Ah-horizon soils, Fe-rich B-horizon soils, C-horizon soils, tree cores of Jack pine (Pinus banksiana), and glacially dispersed boulders of Manitou Falls Formation sandstone that host the U deposit were collected in four sampling grids near the mine site. Two of the grids overlaid the trace of the P2 fault that hosts the deposit and extends nearly to the surface, one grid overlaid both the P2 fault and one of the high-grade ore bodies (Zone 4), and one grid was located 2.5 km away from the ore body surface trace in the barren hanging wall of the P2 fault. The grid overlying the Zone 4 ore body had the highest proportion of samples with elevated U and low 207Pb/206Pb ratios, the latter indicative of radiogenic Pb from a high-U source, measured in two size fractions of Ah-horizon soils using Na pyrophosphate leach, pine tree cores using total digestion, and sandstone boulders using 2% HNO3 leach. A handful of pathfinder elements, such as As, Co, Ni, and Pb, are variably associated with the U and radiogenic Pb. Sandstone boulders with an assemblage of dravite + kaolinite ± illite, determined using shortwave infrared (SWIR) spectroscopy and matching the alteration mineralogy in the Manitou Falls Formation above the U deposit, were prevalent in the grid above the Zone 4 ore body and in the adjacent grid in the direction of glacial dispersion. A coarse fraction of the B-horizon soils, leached with 5% HNO3, highlighted the grid above the Zone 4 ore body to a lesser extent, whereas HNO3 leaches and aqua regia digests of C-horizon soil separates did not highlight the P2 fault or ore body trace due to influence by parent till mineralogy. Results of environmental monitoring at the mine site, which was active at the time of sampling, suggest that dust containing U, Pb, and radionuclides from waste rock piles and a ventilation shaft could influence A-horizon soil geochemistry near the mine site, and that U and radiogenic Pb anomalies in B- and C-horizon soils near the water table are close to a treated mine effluent discharge point. However, older trees that record elevated U and radiogenic Pb in annual rings that pre-date mining activity, and alteration mineralogy and geochemistry of boulders that are less susceptible to the influences of mining activity, add confidence that the geochemical anomaly in diverse surficial media above the Zone 4 ore body represents secondary dispersion from the underlying U deposit.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Pathfinder elements'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles