Energy-Dispersive XRF Analysis of Intact Salt Drill Cores

1984 ◽  
Vol 28 ◽  
pp. 189-194
Author(s):  
R. J. Arthur ◽  
J. C. Laul ◽  
N. Hubbard
Keyword(s):  
Laboratory Analysis ◽  
Energy Dispersive ◽  
Drill Core ◽  
Chemical Analyses ◽  
Chemical Profile ◽  
Xrf Analysis ◽  
The Core ◽  
Drill Cores

Several kilometers of drill core are sometimes obtained when the geology of a particular area is explored. The cores are visually inspected and a limited number of samples are taken for laboratory analysis. Accurate chemical analyses are usually performed on only a small number of core sections because of the expense involved. A chemical profile along the core may provide useful information not available by any other means. This information may be of primary value for geological investigations or it may provide an additional basis for selecting samples for detailed laboratory analyses.

scholarly journals An innovative optical and chemical drill core scanner

2015 ◽  
Vol 19 ◽  
pp. 13-16 ◽  
Author(s):  
A. S. L. Sjöqvist ◽  
M. Arthursson ◽  
A. Lundström ◽  
E. Calderón Estrada ◽  
A. Inerfeldt ◽  
...  
Keyword(s):  
High Resolution ◽  
Sample Preparation ◽  
Fluorescence Spectrometry ◽  
Drill Core ◽  
X Ray ◽  
Xrf Analysis ◽  
The Core ◽  
Single Person ◽  
Scanning Path ◽  
Drill Cores

Abstract. We describe a new innovative drill core scanner that semi-automatedly analyses drill cores directly in drill core trays with X-ray fluorescence spectrometry, without the need for much sample preparation or operator intervention. The instrument is fed with entire core trays, which are photographed at high resolution and scanned by a 3-D profiling laser. Algorithms recognise the geometry of the core tray, number of slots, location of the drill cores, calculate the optimal scanning path, and execute a continuous XRF analysis of 2 cm width along the core. The instrument is equipped with critical analytical components that allow an effective QA/QC routine to be implemented. It is a mobile instrument that can be manoeuvred by a single person with a manual pallet jack.

Energy-Dispersive XRF Analysis of Intact Salt Drill Cores

1985 ◽  
pp. 189-194 ◽  
Author(s):  
R. J. Arthur ◽  
J. C. Laul ◽  
N. Hubbard
Keyword(s):  
Energy Dispersive ◽  
Xrf Analysis ◽  
Drill Cores

DRILL‐CORE SCANNING FOR RADIOELEMENTS BY GAMMA‐RAY SPECTROMETRY

Geophysics ◽  
1972 ◽  
Vol 37 (4) ◽  
pp. 675-693 ◽  
Author(s):  
Leif Løvborg ◽  
Harold Wollenberg ◽  
John Rose‐Hansen ◽  
Bjarne Leth Nielsen
Keyword(s):  
Gamma Ray ◽  
Gamma Ray Spectrometry ◽  
Drill Core ◽  
The Core ◽  
Rock Drill ◽  
Continuous Scanning ◽  
Diameter Core ◽  
Channel Analyzer ◽  
Drill Cores

A system has been developed for the continuous and stepwise scanning of rock drill cores for gamma‐ray spectrometric determinations of uranium, thorium, and potassium. The apparatus accomodates 3‐ to 4‐cm‐diameter core as it passes two opposing 2‐inch diameter by 3‐inch‐ thick NaI(Tl) detectors, either continuously, at speeds ranging from one to several meters per hour, or in steps of 5 cm or more. Resulting gamma‐ray spectra, as recorded with a multi channel analyzer, are computer processed, furnishing scale diagrams of individual radioelement contents and Th/U ratios in the core. Whole‐rock assays of one‐meter‐long core sections by continuous scanning are accurate and precise to within 10 percent or better. In the step‐scanning mode, the system can resolve peak concentrations of U and Th with an accuracy of about 15 percent. Continuous one‐meter scans of 3500 m of core from the Ilímaussaq intrusion, South Greenland, provided an evaluation of uranium resources in the course of seven months. Examination of the continuous‐scan diagrams indicated areas of geochemical interest, such as sharp and transitional contacts and mineralized zones. These were investigated more closely by step scanning, disclosing detailed variations of U and Th. Contents of U and Th determined by scanning of drill core were consistent with the gross gamma‐ray counting rates measured in the boreholes.

scholarly journals CO2-brine injectivity tests in high co2 content carbonate field, sarawak basin, offshore east Malaysia

2019 ◽  
Vol 89 ◽  
pp. 04005 ◽  
Author(s):  
A Giwelli ◽  
MZ Kashim ◽  
MB Clennell ◽  
L Esteban ◽  
R Noble ◽  
...  
Keyword(s):  
Packed Column ◽  
Core Sample ◽  
Chemical Analyses ◽  
Core Flooding ◽  
Flow Rates ◽  
X Ray ◽  
The Core ◽  
Reservoir Conditions ◽  
Post Test ◽  
Porosity And Permeability

We conducted relatively long duration core-flooding tests on three representative core samples under reservoir conditions to quantify the potential impact of flow rates on fines production/permeability change. Supercritical CO2 was injected cyclically with incremental increases in flow rate (2─14 ml/min) with live brine until a total of 7 cycles were completed. To avoid unwanted fluid-rock reaction when live brine was injected into the sample, and to mimic the in-situ geochemical conditions of the reservoir, a packed column was installed on the inflow accumulator line to pre-equilibrate the fluid before entering the core sample. The change in the gas porosity and permeability of the tested plug samples due to different mechanisms (dissolution and/or precipitation) that may occur during scCO2/live brine injection was investigated. Nuclear magnetic resonance (NMR) T2 determination, X-ray CT scans and chemical analyses of the produced brine were also conducted. Results of pre- and post-test analyses (poroperm, NMR, X-ray CT) showed no clear evidence of formation damage even after long testing cycles and only minor or no dissolution (after large injected pore volumes (PVs) ~ 200). The critical flow rates (if there is one) were higher than the maximum rates applied. Chemical analyses of the core effluent showed that the rock samples for which a pre-column was installed do not experience carbonate dissolution.

Lydian Sardis and Its Sphere of Influence in the Light of Laboratory Analysis Results

2020 ◽  
Vol 26 (1) ◽  
pp. 112-145
Author(s):  
Pierre Dupont ◽  
Vasilica Lungu
Keyword(s):  
Close Relationships ◽  
Data Bank ◽  
Laboratory Analysis ◽  
Chemical Analyses ◽  
Small Collection ◽  
Sphere Of Influence ◽  
Greek Pottery

Abstract Alongside its programme of chemical analyses of Archaic East Greek pottery, the Lyon Laboratory for Archaeometry has also looked into the field of Anatolian wares, first of all through additional samples from Lydian Sardis and from Kelainai, as well as with a small collection from Daskyleion. The results obtained enriched our data bank of valuable references on these sites and led to useful comparisons with the Greek settlements of Old Smyrna and Ephesus, both in close relationships with the Lydian sphere.

Hyperspectral drill-core imaging for ore characterization

2020 ◽  
Author(s):  
Laura Tusa ◽  
Mahdi Khodadadzadeh ◽  
Margret Fuchs ◽  
Richard Gloaguen ◽  
Jens Gutzmer
Keyword(s):  
Machine Learning ◽  
Remote Sensing ◽  
High Resolution ◽  
Hyperspectral Imaging ◽  
Mineral Exploration ◽  
Electromagnetic Spectrum ◽  
Drill Core ◽  
Ore Characterization ◽  
Ore Types ◽  
Drill Cores

<p>Mineral exploration campaigns represent an essential step in the discovery and evaluation of ore deposits required to fulfil the global demand for raw materials. Thousands of meters of drill-cores are extracted in order to characterize a specific exploration target. Hyperspectral imaging is recently being explored in the mining industry as a tool to complement traditional logging techniques and to provide a rapid and non-invasive analytical method for mineralogical characterization. The method relies on the fact that minerals have different spectral responses in specific portions of the electromagnetic spectrum. Sensors covering the visible to near-infrared (VNIR) and short-wave infrared (SWIR) are commonly used to identify and estimate the relative abundance of minerals such as phyllosilicates, amphiboles, carbonates, iron oxides and hydroxides as well as sulphates (Clark, 1999). The distribution of these mineral phases can frequently be used as a proxy for the distribution of ore minerals such as sulphides. Typical core imaging systems can acquire hyperspectral data from a whole drill-core tray in a matter of seconds. Available sensors record data in several hundreds of contiguous spectral bands at spatial resolutions around 1 mm/pixel.</p><p>​​In this work, we apply a local high-resolution mineralogical analysis, such as SEM-MLA (Kern et al., 2018), for a precise and exhaustive mineral mapping of some selected small samples. We then upscale these mineralogical data acquired from thin sections to drill-core scale by integrating hyperspectral imaging and machine learning techniques. Our proposed method is composed of two main steps. In the first step, after initially co-registering the hyperspectral and high-resolution mineralogical data and making a training set, a machine learning model is trained. In the second step, we apply the learned model to obtain mineral abundance and association maps over entire drill-cores.</p><p>​​The mapping is further used for the calculation of other mineralogical parameters essential to exploration and further mining stages such as modal mineralogy, mineral association, alteration indices, metal grade estimates and hardness. The proposed methodological framework is illustrated on samples collected from a porphyry type deposit, but the procedure is easily adaptable to other ore types. Therefore, this approach can be integrated in the standard core-logging routine, complementing the on-site geologists and can serve as background for the geometallurgical analysis of numerous ore types.  </p><p>​​</p><p>​​Clark, R. N., 1999, “Spectroscopy of rocks and minerals, and principles of spectroscopy,” in Remote sensing for the earth sciences: Manual of remote sensing, vol. 3, John Wiley & Sons, Inc, pp. 3–58.</p><p>​​Gandhi, S. M. and Sarkar, B. C., 2016, “Drilling,” in Essentials of Mineral Exploration and Evaluation, pp. 199–234.</p><p>​​Kern, M., Möckel, R., Krause, J., Teichmann, J., Gutzmer, J., 2018. Calculating the deportment of a fine-grained and compositionally complex Sn skarn with a modified approach for automated mineralogy. Miner. Eng. 116, 213–225.</p>

Geochemical indicator of the efficiency of fractionation of the Skaergaard intrusion, East Greenland

1975 ◽  
Vol 40 (311) ◽  
pp. 285-291 ◽  
Author(s):  
Paul Henderson
Keyword(s):  
Liquid Phase ◽  
The Body ◽  
Drill Core ◽  
Skaergaard Intrusion ◽  
Average Efficiency ◽  
East Greenland ◽  
Quantitative Indicator ◽  
The Core ◽  
Geochemical Indicator ◽  
Degree Of Separation

SummaryWhen magmatic fractionation involves the settling and removal of crystals from the body of magma, the efficiency of the fraetionation process may be defined as the degree of separation of the solid from the liquid phase. An expression is given that relates efficiency to the amount of mesostasis, or crystallized trapped liquid, in an igneous cumulate. The uranium contents of samples from a 349-m-long drill-core of part of the lower and hidden zones of the Skaergaard intrusion are used as a quantitative indicator of the amounts of mesostasis in the cumulates. There are marked changes in the amount of mesostasis over the length of the core and the average efficiency of fractionation was 85 %.

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