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.

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.

scholarly journals MAGNETIC SUSCEPTIBILITY AND GAMMA-RAY SPECTROMETRY ON DRILL CORE: LITHOTYPE CHARACTERIZATION AND 3D ORE MODELING OF THE MORRO DO PADRE NIOBIUM DEPOSIT, GOIÁS, BRAZIL

2015 ◽  
Vol 33 (2) ◽  
Author(s):  
Marta Henriques Jácomo ◽  
Tereza Cristina Junqueira Brod ◽  
Augusto Cesar Bittencourt Pires ◽  
José Affonso Brod ◽  
Matheus Palmieri ◽  
...  
Keyword(s):  
Magnetic Susceptibility ◽  
Late Cretaceous ◽  
Gamma Ray ◽  
Gamma Ray Spectrometry ◽  
Drill Core ◽  
Carbonatite Complex ◽  
Central Brazil ◽  
Rock Types ◽  
Drill Holes ◽  
Fresh Rock

ABSTRACT. The Morro do Padre niobium Deposit, in the Late-Cretaceous Catal˜ao 2 alkaline-carbonatite complex, central Brazil, consists of stockworks of nelsonite and carbonatite dykes intruded into Precambrian phyllites, quartzites, and amphibolites. A gamma-ray spectrometry and magnetic susceptibility petrophysical survey was conducted on the cores of 73 drill holes in fresh-rock, producing a total of 1295 geophysical samples. Nelsonite, the host rock of the niobium mineralization in the Morro do Padre Deposit, has a characteristic geophysical signature, with higher gamma-ray spectrometry counting rates and magnetic susceptibility values, compared to other rock types. The studied nelsonites may be divided into N1 and N2 types. N2 nelsonite is richer in K, U and Th than N1. Carbonatites are divided into magnetic (C1) and nonmagnetic (C2) varieties. The nonmagnetic carbonatites can be subdivided into C2a and C2b. The C2a carbonatite is richer in K, U and Th than C2b, which is consistent with the presence of apatite and/or monazite in the former. The geophysical 3Dmodeling has shown that the main mineralized body is elongated in the E-W direction. It is about 100 m wide and 300 m long with a maximum depth of approximately 850 m reached by drilling.Keywords: 3D ore modeling, niobium ore, applied geophysics, alkaline rocks, nelsonite. RESUMO. O depósito de nióbio do Morro do Padre no complexo carbonatítico alcalino de Catalão 2 do Cretáceo Superior, região central do Brasil, consiste em stockworks de nelsonito e diques de carbonatito intrudidos em filitos pré-cambrianos, quartzitos e anfibolitos. A pesquisa petrofísica de gamaespectrometria e de susceptibilidade magnética foi realizada em testemunhos de 73 furos de sondagem em rocha fresca, produzindo um total de 1.295 amostras. Nelsonito, a rocha hospedeira da mineralização de nióbio no depósito Morro do Padre, tem uma assinatura geofisica característica, com maiores taxas de radiação gamaespectrométrica e maiores valores de susceptibilidade magnética em comparação com outros tipos de rochas. Os nelsonitos estudados podem ser divididos em N1 e N2. O nelsonito N2 é mais rico em K, U e Th do que o N1. Carbonatitos são divididos em magnéticos (C1) e não magnéticos (C2). Os carbonatitos não magnéticos podem ser subdivididos em C2a e C2b. O carbonatito C2a é mais rico em K, U e Th do que o C2b, o que é consistente com a presença de apatita e/ou monazita na composição minerológica. O modelamento 3D revela um corpo principal de nelsonito mineralizado, alongado segundo a direção E-W. Este é cerca de 100 m de largura e 300 m de comprimento, com uma profundidade máxima de 850 m.Palavras-chave: modelamento 3D de minério, minério de nióbio, geofísica aplicada, rochas alcalinas, nelsonito.

scholarly journals Radioactivity Concentrations in Soil Samples from Kandam, Gyalgyal, Burmawan masaka, Dinbisu and Giyawa Mines in Wurno LGA, Sokoto State, Nigeria

2018 ◽  
pp. 1-9
Author(s):  
Y. M. Ahijjo ◽  
A. N. Baba-Kutigi ◽  
M. Momoh ◽  
A. M. Bayawa ◽  
M. Hussain
Keyword(s):  
Hpge Detector ◽  
Gamma Ray ◽  
Soil Samples ◽  
Gamma Ray Spectrometry ◽  
Sample Population ◽  
Radiological Parameters ◽  
Activity Concentrations ◽  
The Mean ◽  
Channel Analyzer ◽  
Elevated Exposure

Aims: This study was conducted in a bid to ascertain the concentration of NORMS in the soil samples dugout of some mining sites in Kandam, Gyalggal, Burmawan masaka, Dinbisu and Giyawa town in Wurno LGA, Sokoto State Nigeria. The concerns about NORMS radioactivity in the environment are frequently linked to natural radioactivity which is more of primordial radionuclides. Study Design: A total number of nine soil samples were randomly collected for this study. The randomness was in order to represent over 90% of the sample population of different mines in Wurno LGA, Sokoto state for the analysis of gamma-ray spectrometry of High Purity Germanium (HPGe) detector coupled to a Multi-Channel Analyzer (MCA). Place and Duration of Study: Department of Physics, Usmanu Danfodiyo University, Sokoto, Nigeria, between August 2015 and June 2016. Methodology: The concentrations of the radionuclides (226Ra, 232Th and 40K) were ascertained through a high-resolution gamma-ray spectrometry of HPGe detector coupled with a Multi-Channel Analyzer, Centre for Advanced Studies in Physics (CASP), Government College University (GCU), Lahore, Pakistan. The activity concentrations of 226Ra, 232Th and 40K in the soil samples were obtained and used to calculate the radiological parameters ( Raeq, Hex, Hin, DAbs and Deff ) in order to assess the radiological impacts on the inhabitants. Results: The mean activity concentrations for 226Ra, 232Th and 40K in the soil samples were found to be 58.34, 53.76 and 679.70 Bqkg-1 while the radiological hazards parameters revealed mean values of 187.55 Bqkg-1, 0.51, 0.66, 87.77 nGy.h-1 and 107.64 μScyr -1 for Raeq, Hex, Hin, DAbs  and Deff respectively. These were compared with the results of similar studies conducted elsewhere and around the world. It was noticed that 40K contributes the highest level of radioactivity in this study which could enhance the amount of background radiation received by the population in the study area. The activity concentration unveiled from the soil samples were considerably lower for 226Ra and 232Th when compared to the activity of 40K. The mean value of the doseused to calculate the radiological parameters calculations shows that an elevated exposure to radioactivity by the inhabitants around this mine is eminent.  Conclusion: Cancer and various forms of ailment due to radioactivity exposure are further anticipated for the workers in the pits and the dwelling communities.

Determination of radioactive contaminants in sediment and sand samples from the Black Sea by HPGe Gamma-ray spectrometry

2020 ◽  
Vol 55 (2) ◽  
pp. 141-145
Author(s):  
H. Yücel ◽  
R. Güven ◽  
İ. Demirel
Keyword(s):  
Black Sea ◽  
Gamma Ray ◽  
Industrial Wastes ◽  
Coastal Pollution ◽  
The Black Sea ◽  
Gamma Ray Spectrometry ◽  
Inorganic Contaminants ◽  
The Core ◽  
Radionuclide Contamination

The radionuclide activities were measured in sea sediment and coastal sand samples taken from the Black Sea to improve the understanding on coastal pollution as sediments and sand act as a sink for inorganic contaminants from various sources. The core sediments were taken from the Black Sea near to Varna city and sand samples were collected from in the Black Sea Coastal of North Anatolia. Their radionuclide contents were measured using a high resolution gamma-ray spectrometry. The activity results are found to be on the average, 65 ± 9 Bq · kg−1 for 210Pb, 13 ± 1 Bq · kg−1 for 137Cs, 36 ± 4 Bq · kg−1 for 226Ra, 25 ± 3 Bq · kg−1 for 232Th, and 403 ± 13 Bq · kg−1 for 40K in slices from the sediment core. The radionuclide activities in sand samples collected from the Black Sea coastal are measured for 7Be (2.4 ± 0.4 to 5.8 ± 0.4 Bq · kg−1) and for 137Cs (2.0 ± 0.1 to 3.7 ± 0.2 Bq · kg−1). In sand samples, other natural occurring radionuclides 226Ra (6.8 ± 1.1 to 12.5 ± 1.3 Bq · kg−1), 232Th (6.5 ± 0.8 to 16.9 ± 1.4 Bq · kg−1) and 40K(139 ± 8 to 376 ± 16 Bq · kg−1) were also observed, as expected. The present results indicate that there is still noticeable radionuclide contamination in sediments and coastal sands due to mainly the Chernobyl nuclear accident and other conventional industrial wastes.

Gamma-Ray Spectrometric Analysis of Some Trace Elements in the Human Articular Disc of the Mandible

1963 ◽  
Vol 03 (02) ◽  
pp. 175-182 ◽  
Author(s):  
Bo Bergman ◽  
Rune Söremark
Keyword(s):  
Trace Elements ◽  
Neutron Activation ◽  
Quantitative Data ◽  
Thermal Neutron Flux ◽  
Gamma Ray ◽  
Dry Weight ◽  
Gamma Ray Spectrometry ◽  
Spectrometric Analysis ◽  
Articular Disc ◽  
Group Separation

SummaryBy means of neutron activation and gamma-ray spectrometry the concentrations in the human mandibular articular disc of the following elements have been determined: Na, Mn, Cu, Zn, Rb, Sr, Cd, W, and Au. The discs were obtained at necropsy from seven men and nine women, ranging in age from 56 to 71 years.The activation was carried out in a thermal neutron flux of about 1.7 XlO12 neutrons × cm−2 × sec.−1 for about 20 hours. A chemical group separationwas performed before the gamma-ray spectrometry. Quantitative data based on the dry weight of the cartilage samples were obtained by comparing the photo-peak area of the identified elements with those of appropriate standards.

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