THE TOTAL GAMMA RAY ACTIVITY OF SEDIMENTARY ROCKS AS INDICATED BY GEIGER COUNTER DETERMINATIONS

Geophysics ◽  
1944 ◽  
Vol 9 (2) ◽  
pp. 180-216 ◽  
Author(s):  
W. L. Russell

Geiger counter determinations of the gamma ray intensity of 510 rock samples have been made to determine the average radioactivity and frequency distribution of radioactivities of the various types of sedimentary rocks. The results, expressed in units of gamma ray intensity, show that limestones, sandstones and dolomites are of relatively low radioactivity, shales much higher, and black bituminous shales highest of all. The new data on the gamma radiation of the sediments may be used to improve the interpretation of radioactivity logs and to determine the value of surface radioactivity surveys.

2019 ◽  
Vol 26 (1-2) ◽  
Author(s):  
Jiří Zimák ◽  
Marek Slobodník ◽  
Přemysl Pořádek

This paper deals with the natural radioactivity of Palaeozoic rocks on the map sheets 15- 31 Bruntál and 15-33 Moravský Beroun in the NE part of the Bohemian Massif. Studied rocks belong to the Vrbno Group (greenschists and phyllites) and mainly to the MoravoSilesian Palaeozoic, particulary to the Andělská Hora, Horní Benešov and Moravice Fms. Potassium, uranium and thorium contents were measured in 1 596 rock samples using a laboratory gamma–ray spectrometer, values of mass activity of 226Ra equivalent (am) were calculated. The average am of analysed rock samples is 138 Bq.kg-1. This value is very close to the am value calculated for the average continental crust. Natural radioactivity of flysch sedimentary rocks of the Andělská Hora, Horní Benešov and Moravice Fms. (1 350 analysed samples, avg. am = 150 Bq.kg-1) grows from psefi tes (conglomerates) to psammites (dominating greywackes) up to the group of aleurites and pelites (siltstones, silty shales, clay shales). The highest uranium and thorium contents, along with other metals (Cs, Ga, Rb, Sn, Zr, La, Ce, Pb, Zn, As) were found in flysch rocks of the Horní Benešov Fm. in the area near Valšov: greywacke shows content up to 13 ppm U and 25 ppm Th (am = 364 Bq.kg-1) and siltstone up to 21 ppm U and 43 ppm Th (am = 624 Bq.kg-1). Low-grade metamorphic mobilization of elements is documented by hydrothermal minerals in syntectonic quartz veins which are e.g. fluorite, sulphides, REE-bearing phases, U-bearing phases.


2018 ◽  
Vol 25 (1-2) ◽  
Author(s):  
Jiří Zimák

This paper deals with natural radioactivity of Palaeozoic sedimentary rocks in the map sheets 25-11 Hlubočky and 25-12 Hranice. All studied rocks belong to the Moravo-Silesian Palaeozoic, namely to three flysch formations (Horní Benešov, Moravice and Hradec-Kyjovice fms.) and two carbonate formations (Macocha and Líšeň fms.). Contents of potassium, uranium and thorium were measured using a laboratory gamma–ray spectrometer in 1 337 rock samples, values of mass activity of 226Ra equivalent (am) were calculated. The data are tabled and discussed. The average am of analysed flysch sediments is 160 Bq.kg-1. This value is very close to the value of am calculated for the average continental crust. Natural radioactivity of flysch sedimentary rocks grows from psefites (conglomerates) through psammites (graywackes dominate) to the group of aleurites and pelites (siltstones, silty shales, clay shales). Natural radioactivity of the studied carbonate rocks is very low. In dark biodetritic limestones of the Líšeň Fm. there were found slightly increased uranium contents (typically up to 6 ppm). Uranium in the rock is probably bound to graphitic matter.


2018 ◽  
Vol 1 (1) ◽  
pp. 26-31 ◽  
Author(s):  
B Babu ◽  
K Mohanraj ◽  
S Chandrasekar ◽  
N Senthil Kumar ◽  
B Mohanbabu

CdHgTe thin films were grown onto glass substrate via the Chemical bath deposition technique. XRD results indicate that a CdHgTe formed with a cubic polycrystalline structure. The crystallinity of CdHgTe thin films is gradually deteriorate with increasing the gamma irradiation. EDS spectrums confirms the presence of Cd, Hg and Te elements. DC electrical conductivity results depicted the conductivity of CdHgTe increase with increasing a gamma ray dosage


Author(s):  
Amy Luan ◽  
BCIT School of Health Sciences, Environmental Health ◽  
Bobby Sidhu ◽  
Abderrachid Zitouni

  Abstract: Due to the Fukushima Daiichi Nuclear power plant incident in March 2011, large quantities of contaminated water were released to the Pacific Ocean in Japan. The severity of contamination on the marine environment is unclear, therefore, the public is concerned with the possible internal radiation exposure from ingesting contaminated seafood products caught in the Pacific Ocean. This study was aimed to investigate the presence or absence of gamma radioactivity in commonly consumed seafood products from B.C. In total, ten different species of fish and three different species of shellfish were selected for analysis. For each species of fish, two samples were collected and each sample was from a different local seafood market. For each species of shellfish, ten samples were collected from three different sources. Using the portable GR-135 Plus gamma ray spectrometer, the samples were tested and analyzed for the presence of Fukushima radionuclides, particularly Cesium-137 (Cs-137) and Cesium- 134 (Cs-134).Based on the analyzed fish and shellfish, no gamma radiation was detected. The detector did not identify any gamma radiation over the normal background readings.  


Author(s):  
Anthonia Nwanese Asadu ◽  
Charles Ojonuba Ameh

Fifty ditch cutting rock samples from well Z-1, OPL 310 offshore Dahomey basin, south western Nigeria were analyzed for their microfaunal and lithofacies content for the purpose of reconstructing the environment of deposition. Standard techniques of foraminifera slide processing and analysis was followed for the recovery of foraminifera while the gamma ray log complemented the rock samples for the lithofacies analysis. The lithological analysis revealed two lithofacies units in a generally fining upward sequence. The basal sandstone unit is characteristically milky white to brownish, coarse-pebbly grained, sub-angular to round and poorly to well sort with intercalation of shale. This unit is overlain by light to dark grey, moderately hard and non-fissile shale/mudstone sequence with intercalation of sand. Accessory mineral assemblage present in the formations includes mica flakes, glauconite pellets, carbonaceous detritus and ferruginous materials. The basal sandstone unit belong to the Oshosun Formation while the upper shaly unit is typical of Afowo Formation. Microfaunal study showed good recovery of abundant and well diversified planktic and benthic foraminiferal species. Forty-two (42) planktic, sixty-five (65) benthic calcareous and one benthonic arenaceous foraminiferal species were recovered. Micropaleontologically, Paleoenvironmental deductions were based primarily on the assemblage, abundance and diversity of benthic foraminiferal species and presence or absence of planktic foraminifera. Accessory mineral presence also aided the interpretations. Integration of lithological and micropaleontological synthesis enhanced the delineation of two environmental subzones over the analyzed interval, the outer neritic and the upper bathyal depositional settings corresponding to Afowo and Oshosun Formation respectively. A lowstand prograding wedge which is a good exploration target offshore was recognized between intervals 3400 ft to 3500 ft. In conclusion, the rock succession studied, penetrated Afowo and Oshosun Formations, and were deposited in an environment ranging from outer neritic to upper bathyal settings.


2020 ◽  
Author(s):  
Jan Kisiel ◽  
Kinga Polaczek-Grelik ◽  
Katarzyna Szkliniarz ◽  
Agata Walencik-Łata ◽  
Jari Joutsenvaara ◽  
...  

<p>The BSUIN (Baltic Sea Underground Innovation Network) aims to enhance the accessibility of the underground laboratories in the Baltic Sea region for innovation, business and science. One of the BSUIN project activities is characterization of natural background radiation (NBR) in underground facilities. In this talk results from NBR measurements performed in Callio Lab, Pyhäsalmi, Finland, at the depth of 4100 m w.e. will be presented. The in-situ gamma spectra were collected with the use of  HPGe semiconductor spectrometer, whereas the  concentration of radon were measured with RAD7 electronic detector. In addition, the water and rock samples were taken for laboratory analysis in Institute of Physics, University of Silesia, Poland. The concentration radioisotopes in water samples were performed by using a liquid scintillation α/β counter (LSC) and α-particle spectrometry, while the concentration of radioisotopes in rock samples were performed by using laboratory gamma ray spectrometry and also α-particle spectrometry.</p>


2017 ◽  
Vol 24 (1-2) ◽  
Author(s):  
Jiří Zimák

The paper deals with natural radioactivity of metamorphic and igneous rocks and Palaeozoic sediments within the map sheet 14-33 Polička. Studied rocks belong to three geological units: the Hlinsko Zone (phyllites and quartzites of the Mrákotín Fm., flysch sediments of the Hlinsko-Rychmburk Fm.), the Svratka Crystalline Complex (mainly mica schists, paragneisses, orthogneisses and migmatites, also amphibolites, skarns, erlans and quartzites) and the Polička Crystalline Complex (mica schists, paragneisses to migmatites and the Variscan granitoids are dominant). Concentrations of potassium, uranium and thorium were measured using a laboratory gamma-ray spectrometer in 805 rock samples. Data are tabled and discussed. Natural radioactivity of rocks is evaluated on the basis of the calculated values of mass activity of 226Ra equivalent (am). Slightly increased am values were found in migmatites and orthogneisses of the Svratka Crystalline Complex (187 Bq.kg-1 on average), granites and granodiorites of the Budislav Pluton (216 Bq.kg-1), granodiorites and rocks of a tonalite suite of the Miřetín Pluton (199 and 194 Bq.kg-1). Increased concentrations of uranium and thorium were found in some samples of pegmatite and aplite. Radioactivity of rocks of the Hlinsko-Rychmburk and Mrákotín Fms. can be assessed as relatively low.


2007 ◽  
Vol 17 (03n04) ◽  
pp. 193-203 ◽  
Author(s):  
R. RAVISANKAR ◽  
A. RAJALAKSHMI ◽  
P. ESWARAN ◽  
V. MEENAKASHISUNDRAM ◽  
V. GAJENDIRAN ◽  
...  

Beach rock samples collected from South East Coast of Tamilnadu was analyzed by natural radioactive measurements to detect the presence of radioactive elements. PIXE technique was used to obtain elemental composition of beach rocks. The PIXE analysis was carried out using 1.7 MV tandem accelerators with the energy of 2 MeV protons at Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam, Tamilnadu, India. The geochemical behavior of the elements in the region is discussed. The occurrence of the radioactive and non-radioactive elements is discussed for their geological significance. The results were used to assess environmental toxicity of heavy metals and radiation hazard in the study area.


Geophysics ◽  
1987 ◽  
Vol 52 (11) ◽  
pp. 1557-1562 ◽  
Author(s):  
A. A. Green

A procedure for estimating background‐correction terms for the uranium channel of an airborne gamma‐ray survey has been developed. The residuals obtained from a multiple linear regression of flight‐line means for the uranium channel on the means for thorium and potassium are used to correct the uranium channel for each line. The procedure assumes that, were it not for these background errors, the uranium flight‐line means would be a linear function of the means for potassium and thorium. It also assumes that the background correction is the same for the whole of each line. In spite of these limitations, the method produces good background estimates consistent with those found by more sophisticated methods.


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