Thorium Concentrations Research Articles

Gamma-radiation levels outdoors in Great Britain based on K, Th and U geochemical data

Gamma-rays from naturally occurring radionuclides are a major component of background radiation. They are an important tool for geology and are also important for radiation protection. In this paper we use over a quarter of a million geochemical measurements of concentrations of potassium, thorium and uranium in soils and in stream sediments to estimate outdoor gamma-ray dose rates across Great Britain. The soil concentrations are generally at a depth of 5–20 cm with some at 35–50 cm. Soil measurements will give spatially relatively precise estimates, but as soil data are not available for much of Scotland, stream sediment data are used there. Kriging methods are used to estimate surface concentrations of K, Th and U and dose rates are imputed from these concentrations. Our results are compared with measurement surveys of both outdoor and indoor gamma-ray dose rates. Recently there has been interest in exploring the carcinogenic risks of low dose radiation by investigating associations between childhood cancer rates and doses from natural background gamma radiation. To achieve adequate statistical power, such studies must be so large that it is impractical to assess exposures by direct measurements in the homes of study subjects. Instead the exposures must be modelled. The results presented here will be an important input to such work.

Genetic Analysis of Abnormally High Ground Temperature From the Existence of Magmatic Rock Beneath Pingdingshan Coalfield

Studies on the genetic mechanisms of abnormally high ground temperatures in coalfields are of great significance for the efficient mining of coal mines and the development and utilization of geothermal water. Therefore, we measured the temperature of 45 Cambrian limestone groundwater samples, thermal conductivity values of 11 Cambrian limestone samples, and the contents of uranium, thorium, and potassium-40 of 40 rock samples, aiming to ascertain the heat source of the abnormally high ground temperature in the Pingdingshan coalfield. The results show that the average geothermal gradient in the coalfield is about 3.32°C/100 m, and the calculated values of the average ground heat flow are about 104.28 mW/m2, which demonstrate the abnormally high ground temperature in Pingdingshan coalfield. We also concluded that the whole radiogenic heat generation in sedimentary and magmatic rocks is 1.53 mW/m2, whose contribution rate to the local geothermal flow is only 1.47%. Hence, we can infer that magmatic rocks exposed in or near the coalfield area may supply the heat source for the abnormally high ground temperature beneath Pingdingshan coalfield. A comprehensive analysis further shows that the latest intrusion time of the magmatic rock mass in the coalfield was 35 Ma; its lava temperature was 900°C, its cooling rate is 20.0°C/Ma, and the calculated residual temperature is more than 200.0°C. These values support the idea that the magmatic rocks may be the primary cause of the abnormally high ground temperature in the Pingdingshan coalfield.

Assessment of radiological health risk and radiogenic heat production changeability of different sedimentary rocks at Gabal Um Hamd, Southwestern Sinai, Egypt

Soil is a source of natural radionuclides and a source of natural radiation risk to humans. This study aims to measure the radioactivity concentrations, contributions, radiological hazards and to quantify the radiogenic heat productions in thirty two rock samples having different lithology from the middle member of Um Bogma Formation in Gabal Um Hamd, southwestern Sinai, Egypt. The concentration of natural radionuclides was determined using a p-type Hyper Pure Germanium (HPGe) detector. The average activity concentrations of uranium thorium and potassium in the interested area were found to be 4909.58 ± 54.34 5003.12 ± 17.56 79.04 ± 8.82 and 137.35 ± 8.64 respectively. Other hazard indices average values were measured, such as: annual effective dose equivalent, radium equivalent activity, external and internal indices, annual gonad equivalent dose, and excess lifetime cancer risk. The radiologic hazards results, obtained in this study shows that the radiation levels are higher than the internationally approved values and the recommended safety limits. Furthermore, the results show that the radiogenic heat value ranged from 3.58 to 402.45 μW m −3 with an average value of 60.11 ± 0.79μW m −3 in the studied area which is higher than previously reported averages.

External dose assessment of NORM added consumer products using Geant4 Monte Carlo simulations

Radioactive consumer products (RCP) are widely marketed for everyday use. The study herein was conducted on 21 commercially available RCP, including bio-glass discs, energy cards, scalar energy products, and anti-radiation stickers, all purposefully designed to contain naturally occurring radioactive material (NORM). This study investigates the dose influence of such consumer products which acts as external radiation sources that may be in contact with human body. The goal of this study is to assess the potential risk of using NORM-added consumer products, the presence of such products in the living environment unnecessarily exposing members of the public to radiation. A Pb-shielded high purity Ge (HPGe) spectrometer was used to perform the analysis of samples radioactivity levels. Simulations were performed using Geant4 Monte Carlo (GMC) simulations to estimate the equivalent organ doses and annual effective dose (AED) in the use of such products. The total activity in such radioactive consumer products ranges from 2.0 ± 0.1 to 7413 ± 576 Bq, 1.9 ± 0.8 to 1168 ± 131 Bq, and 21 ± 5–574 ± 103 Bq, for 232Th, 238U, and 4 K, respectively. It was found that RCP contains monazite, giving a relatively high concentration of uranium and thorium. The radiological risk posed by the use of such items as healthcare products is assessed, with the daily external exposure doses of particular concern. Dose assessments of the organ equivalent and average effective doses were performed by measuring the activity of 232Th, 238U, and 4 K using the aforementioned products for various exposure duration scenarios. Accordingly, sample A13 a bio-glass disc offered concentrations with mean percentages of 1.29 ± 0.003% and 0.043 ± 0.0003% for Th and U, respectively, giving rise to estimate the greatest annual effective dose exposure of 2.54 mSv among samples, considerably in excess of the public dose limit of 1 mSv y-1

Sorption-photometric definition of thorium (IV) in clays

A simple and selective method for sorption-photometric determination of thorium (IV) micro amounts in clay using a new chelating sorbent, a copolymer of maleic anhydride with styrene modified with N1,N1,N2-triphenylguanidine, is proposed. The sorbent is white substance, insoluble in water, acids, weak alkalis and organic solvents. Sorbents were first ground in an agate mortar and sieved through a sieve (0.14 mm). The effect of pH of the medium, the ionic strength of the solution, contact time of the phases, concentration of thorium (IV) in the solution and on the sorption was studied under static conditions. Thorium concentration was determined by the photometric method using 2,2’,3,4-tetrahydroxy-3’-sulfo-5’-chloro-benzene. The concentration of thorium (IV) was calculated using a calibration curve, the results were processed statistically. The full static sorption capacity of the resulting sorbent on K+ ion was 13 mmol/g. An emphasis was also made on the study of the effect of the kinetic properties of sorbents on the sorption process. The maximum degree of thorium extraction by the sorbent was achieved from the solutions with pH 4. The time dependence of sorption was also studied. The results of the study showed that the sorption equilibrium is achieved after 2.5 h of contact of the sorbent with the metal. The sorption of thorium increases with an increase in the thorium concentration in the solution and attains maximum at a concentration of 8 × 10–3 M (pH 4, = 8 × 10–3 M, Vgen = 20 ml, mabsorbed = 0.05 g, sorption capacity = 348 mg/g). The degree of thorium (IV) extraction in optimal conditions exceeds 95%. It is shown that the main micro- and macro-components of clay do not affect the results of the determination of thorium. The developed technique was applied to determine thorium in a clay sample from the Shemakhi region of Azerbaijan. The correctness of the obtained results was confirmed by the spike test.

Natural radioactivity assessment and geophysical interpretation of parts of Igarra area, Southern Nigeria.

To evaluate the concentration of natural radionuclides and to carry out geophysical interpretation of part of Igarra area, Southern Nigeria, an integrated geophysical approach was adopted involving radiometric, gravity, and magnetic methods. The RS-230 Super-Spec spectrometer, G-512 Lacoste and Romberg gravimeter, and the GSM-19v7.0 Overhauser instrument were used for the radiometric, gravity, and magnetic data acquisitions, respectively, along a specified traverse within the area. The datasets were processed using Oasis Montaj, Grav-Master, and Ms-Excel software. Gravity results show that the mean free air and Bouguer anomalies in the area are - 67.42 and - 84.22 mGal, while magnetic survey indicates that the mean corrected magnetic field intensity in this area is 32218.49 nT. Radiometric survey results show that the mean radioactivity concentrations of thorium ([Formula: see text], uranium ([Formula: see text]), and potassium ([Formula: see text]) are 31.81Bq/kg, 26.48Bq/kg, and 167.33Bq/kg, respectively. Further analysis also revealed that the mean radioactivity equivalent of the area is 84.86Bq/kg; absorbed dose rate is 72.74nGy/h, while the mean external hazard index is 0.30. A novel model equation for estimating absorbed dose rate from radioactivity equivalent was also obtained and validated. The gravity and magnetic survey results indicate the presence of low-density and high magnetic basement rocks underlying this area, while radiometric results reveal that radiations in this area did not exceed acceptable standards of 370Bq/kg for radioactivity equivalent, 84 nGy/h for absorbed dose rate, and unity which corresponds to 370Bq/kg for external hazard index as recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation and the International Atomic Energy Agency.

Removal of Th(IV) from aqueous solution with modified silica gel by 4-hydroxy-N ′ - ((thiophen-2-yl) methylene)benzohydrazide schiff base

ABSTRACT In this study, SiCPMS@L solid adsorbent was prepared using 4-Hydroxy-N ′- ((Thiophen-2-yl)methylene)benzohydrazide Schiff base for thorium(IV) removal from aqueous solution, and the structure of the solid adsorbent was characterized by FTIR, SEM, elemental analysis, and BET surface analysis methods. Solution pH, initial thorium concentration, contact time, adsorbent dose, and temperature parameters affecting the adsorption of Th(IV) ions with SiCPMS@L adsorbent were examined, and optimum uptake conditions were determined. The effective initial pH for adsorption was found to be 4.0. The binding sites on SiCPMS@L solid adsorbent were saturated using an initial Th(IV) concentration of 16.0 mg/L. 30 minutes was determined as the optimum contact time when the adsorption equilibrium was established. The optimum adsorbent dose for SiCPMS@L was determined as 1.0 g/L. At optimum conditions, adsorption efficiency and adsorption capacity values for SiCPMS@L adsorbent were respectively; 97.4% ± 0.1 and 15.6 ± 0.1 mg/g were obtained. The calculated thermodynamic parameters ∆S°, ∆G° and ∆H° showed that the Th(IV) sorption process is thermodynamically advantageous, spontaneous and endothermic. Langmuir, Freundlich and Dubinin-Radushkevich adsorption isotherms for removal of Th(IV) ions with SiCPMS@L solid adsorbent were investigated and found to be compatible with Langmuir isotherm.

Potential Applications of Marine Deposits Assessment Using Radiometric and Geochemical Data Integration in Arewa-Jantulu NW, Nigeria

Exploration for uranium, thorium, potash, and manganese at this time can be seen as a magnitude that can settle into the immense economic benefit to the host community and the country at large. These minerals have transformed the economic landscape of many host countries and they can be mined to contribute significantly to the Nigerian economy. In this study In-situ measurements using Radiometric and trace element analysis of intercontinental deposits discovered by the paleomagnetic analysis were carried out in Arewa-Jantulu part of the Gwandu formation northwestern Nigeria. The present study was aim to measure and characterize the concentration of radioactive anomalies using radiometric and geochemical measurements. Uranium (U), Thorium (Th), and Potassium (%K) as well as the total count (TOT) gamma-ray concentration was measured with a portable Gamma-ray spectrometer. The results of the gamma-ray measurements shows spatial distribution plots of different levels of radioactivity over the studied area, which reflect contrasting radioelements contents for exposures to various rock types. The phase identification of marine soil sediment samples was determined from Atomic Absorption Spectrometry (AAS). While the study has shown the correlation plots of various trace elements versus radioelements concentration as well as the total concentration of some profiles of the study area. This study identified the need for the interpretation of geochemical data in this location to confirm the results obtained are meaningful. The study has also revealed the computed mean and standard deviation for trace elements analysis for ease assessment. For radioelements occurrences, the spatial distribution plots of activity of uranium (eU), thorium (eTh), and (K %) give an indication where high concentrations of thorium and uranium occur.

Study on Morphology and Chemical States of Surface Active Layer of Th-W Cathode.

The surface morphology and chemical states of W-2%ThO2 thermionic cathode during vacuum high-temperature treatment were investigated in this research. The W-2%ThO2 thermionic cathode was prepared by a solid-liquid doping method combined with high-temperature sintering. The morphology and distribution of thorium oxide were observed using a transmission electron microscope and scanning electron microscope. The chemical states of elements at different temperatures were analyzed by X-ray photoelectron spectroscopy. Results indicate that the surface morphology and chemical form of the alloy evolve with the increase of temperature. The matrix had a lamellar structure at low temperatures, and the surface was relatively flat. The samples were heated to 500 °C, 1100 °C, and 1300 °C for 1 h. During the heating process, thorium oxide changed from granular to spherical, and the matrix was recrystallized. As the heating temperature rises, diffusion channels appear inside the cathode. As the temperature increases, the high-priced tungsten gradually decreases, and the zero-valent tungsten content increases. The adsorbed oxygen left the cathode surface, and the lattice oxygen increased. The surface oxygen content decreased, and the thorium and tungsten content increased.

Southeast Asian dust flux reconstructed using accurately dated stalagmite thorium concentrations

Mineral dust flux is an important component of the global climate system, but chronological uncertainties complicate interpretations of the timing and magnitude of paleo-dust fluxes. This study establishes a correlation between modern satellite-derived atmospheric dust concentration data and stalagmite thorium concentrations (from published records of stalagmites growing over the last 500 years), and subsequently applies this relationship to reconstruct Asian dust flux during the late Pleistocene using published records. Thorium is an element often associated with mineral dust, and because most stalagmite records are dated using uranium-thorium disequilibrium techniques, a spatiotemporally large, yet untapped, database of thorium concentrations exists. Specifically, 194 thorium records from South-East (SE) Asian stalagmites were compiled to produce a composite SE Asian dust flux record for the past 100,000 years. The new dust flux record is consistent with the perspective that dust flux is a function of westerly wind strength across Asia and regional aridity. Dansgaard-Oeschger (D-O) event expression within the median stalagmite 232Th record is variable, with several D-O events evident within stalagmite δ18O records not evident within the new dust record. This may reflect East Asian Summer Monsoon (EASM) moisture source region Sea Surface Temperature (SST) variability (affecting stalagmite δ18O) but stable westerly wind regime (resulting in invariant 232Th concentrations) or the fact that these events were too brief to trigger biome shifts. This study presents encouraging first results suggesting that stalagmite thorium concentrations partially reflect dust flux over cave sites. Although here we use a compilation of records, and the spread of data within each time slice is high, future studies at well-understood cave sites where thorium input to the cave is predominantly via dry deposition may require only single stalagmites to produce adequate absolutely dated dust reconstructions.

Release behavior and mechanism of uranium and thorium from Ta-Nb tailings under simulated rainfall in Jiangxi Province, China.

Tantalum-niobium ore belongs to associated radioactive ore, which is accompanied by a certain amount of radioactive uranium and thorium. The remaining slag is enriched with a large number of radionuclides; after weathering, natural rainfall, and surface water scouring, radioactive elements such as uranium, thorium, and some heavy metal elements are exposed or washed into the soil, which poses a threat to the ecological environment and human health. In this study, for characterization analysis during, before, and after leaching, dynamic simulation experiment was carried out on a Ta-Nb slag sample in Jiangxi, China. From SEM analysis, the soluble substances adsorbed on the slag surface dissolve into the solution after leaching in simulated rainfall, and the remained slag becomes smooth with different particle sizes. The XRD diffraction analysis of the sample showed that after leaching in simulated rainfall, the existing forms of elements are different. pH of the leachate of Ta-Nb slag is 1.79; Ta-Nb slag contains many rare metal elements, nonmetal elements, radioactive elements, and some salt compounds; and the content of thorium is higher than that of uranium by EDS analysis. The release of uranium and thorium is obviously affected by the amount of leachate and pH. Under the lower pH of leaching solution, the release of uranium and thorium is more effective. The results of Fick diffusion theory and Elovich equation show that the release and migration mode of uranium and thorium in Ta-Nb slag are mainly surface elution; under acidic conditions, the release and migration of uranium and thorium are faster. This study provides basic data and scientific information for solving the key problems of pollution control of associated radioactive waste in environmental protection.

Isotopic profiling of natural uranium mined from northern Nigeria for nuclear forensic application

Four mined samples of natural uranium from northern Nigeria were studied through inductively coupled plasma mass spectrometry, at the Environmental Analytical Chemistry Laboratory, University of the Witwatersrand, Johannesburg. The samples were characterised for lead, thorium and uranium isotopic concentrations, isotopic ratios and age. The objective was to obtain nuclear forensic fingerprints as baseline data to add to the Nigerian National Nuclear Forensic Library. Results showed significant variation in the isotopic concentrations of lead, thorium and uranium across the mines. Isotopic ratios of 238U/235U, 235U/238U and 234U/238U across the sample of 137.881±0.007, 7.253×10-03±2.05×10-04 and 5.540×10-05±4.08×10-07 were found to be consistent with the natural values. The age of natural uranium is comparable to the age of earth. Uranium, lead, and thorium isotopic concentrations and ratios, as well as the age of the samples characterised, provide an isotopic profile that can be used for nuclear forensic application. Significance: Given the abundant deposits of natural uranium in Africa and the consequent potential for nuclear insecurity, determining the isotopic profiles and signatures of natural uranium is important for application in nuclear forensics. Isotopic concentrations of 232Th, 238U, 235U and 234U from the respective sampling sites differed significantly, thereby providing characteristic isotopic profiles.

Importance of accessory minerals for the vertical distribution of uranium and thorium in soil profiles: A case study of durbachite from the Třebíč Pluton (Czech Republic)

The mineralogical character of a parent rock strongly affects the uranium (U) and thorium (Th) contents of soils. We have selected five representative soil profiles developed on amphibole–biotite to biotite durbachites in the Třebíč Pluton (eastern part of the Czech Republic) to characterize the radioactivity and variable-intensity weathering. The Endoskeletic Cambisols with a silt loam to loamy sand texture and a well-developed subsurface Bw horizon represented the most common product of the pedogenetic processes on durbachites. All studied soil profiles showed the evidence of pedogenetic alteration with intrasoil weathering. They were moderately deep (70–80 cm) with high rock-fragment concentrations within the B and C horizons. The predominant grain size fractions were silt (12% to 83%) or sand (8% to 87%), and the percentage of clay was up to 15%. A feldspar–quartz–vermiculite (biotite)–amphibole–kaolinite–Fe–Mn (oxy) hydroxide assemblage was typical for the most weathered parts of the profiles. Variation in the U and Th contents within the studied soil profiles resulted predominantly from the changes in the amounts of primary accessory minerals at different depth levels. Uraninite, monazite, thorite, allanite, zircon, thorogummite, REE-(Rare Earth Elements) fluorocarbonates, and minerals of the rhabdophane group were the main carriers of radioactive elements in the parent durbachite and overlying soil profiles. The gamma-ray spectrometry, geochemical and mineralogical analyses show that uraninite was stable only in the parent durbachite and disappeared at the rocks–C horizon interface. This process was followed by the gradual alteration of allanites, thorites, brabantites and secondary U- and Th-rich minerals (e.g., thorogummite, bastnäsite) toward the soil surface.

Determination of thorium in the hair and urine of workers and the public in a rare earth mining area

ObjectiveTo assess the thorium exposure of the mine workers and the public to a typical rare earth mine and estimate the resultant committed effective dose to them. MethodsA total of 79 volunteers were selected in this survey, including 69 mine workers and 10 local residents living about 4 ​km away from the mine site. Urinary samples were collected from 79 volunteers, with 65 hair samples from 57 workers and 8 local residents. The thorium concentrations in urinary and hair samples were determined by using inductively coupled plasma mass spectrometry. The committed effective doses were estimated based on the urinary samples collected and the parameters as recommended by ICRP Publication 137. ResultsThorium concentrations in the samples from the workers ranged from 19.0 to 2388.8 ​ng/g in hair with median of 149.8 ​ng/g, and in urine 18.3–906.1 ​ng/L with median of 59.6 ​ng/L, respectively. The median values of thorium concentrations were 11.8 ​ng/g in hair and 32.40 ​ng/L in urine for the public respectively. The thorium concentrations in urinary and hair samples of the workers were not only higher than those of the residents in the local area, but also than those of non-occupationally exposed populations as reported. The median values of committed effective dose were estimated to be 1.51 ​mSv for the workers and 781 ​μSv for the local residents, respectively. ConclusionsThe residents in the local area, and especially the workers, have been subject to long term thorium exposure. More attention should be paid to the radiological hazards of thorium to the workers and local residents.

Estimation of 238U and 232Th in soil and water of prominent fault region of Mizoram

The study investigates radon and thoron concentrations in soil and water at one of the most prominent faults in Mizoram state, India. The obtained isotope pair data were consequently used for estimating the uranium and thorium content of the region. An indigenously developed and calibrated ZnS(Ag) alpha based scintillation counter (Model: SMARTRnDuo, BARC, India) was deployed for assessing radon and thoron data. Thoron concentration was found to be higher than radon concentration in both soil and water. The isotope pair and their parent nuclei concentration in water were found to be higher than in soil. The uranium and thorium content in soil were estimated to be 17.5 and 22.6 Bqkg-1 respectively, but in water, they were estimated to be 41.6 and 124.8 Bqkg-1 respectively. Comparisons with global averages were also presented in detail and no radiological risk has been observed for the region. A continuous radon data was generated at Mizoram University, Aizawl, Mizoram (India) for cross-analysis with data at Mat fault. It was observed that radon data of the two locations behave similarly during geophysical phenomena, indicating that the region was seismically active. No geophysical properties of thoron were observed.

Assessment of rare earth and actinides (U and Th) elements in soil samples from Kapar industrial area, Selangor

The study of rare earth and actinide elements have received attention nowadays due to rapid development in the extraction of the rare earth industry in Malaysia. Soil samples (18 areas) collected from the Kapar industrial area were analysed by using the neutron activation analysis (NAA) technique for the determination of rare earth elements and actinides (U, Th) concentration. The concentration of rare earth element such as La, Ce, Nd, Sm, Eu, Tb, Dy, Yb and Lu were ranged from 14.7-61.4, 30.6-132.8, 11.7-44.0, 2.12-9.60, 0.37-1.43, 0.03-1.57, 2.20-7.45, 0.28-0.81, and 1.99-4.15 mg/kg, respectively. The concentrations of uranium and thorium were a range of < 0.1-6.74 and 12.6-30.1 mg/kg, respectively. The results of geo-accumulation indicate the all-rare earth elements can be categorised as uncontaminated in all areas with an Igeo value below 0. The concentration of U can be categorised as uncontaminated to moderately contaminated (Igeo class 1) with Igeo values of 0 to 1 in the area of D, F, H, I, L, and N, whilst other areas can be categorised as uncontaminated with Igeo value < 0 (Igeo class 0). The thorium concentration in B, L, and N areas can be categorised as moderately contaminated with Igeo value 1 to 2 (Igeo class 2), whilst most of the area can be categorised as uncontaminated to moderately contaminated (Igeo values 0 to 1). The sources of Th contamination most likely originated from the anthropogenic and geogenic processes.

Determination of Uranium and Thorium Contents in Various Material Samples of Morocco Using a New Monte Carlo Code for Evaluating the Mean Critical Angle of Etching of the Cr-39 and Lr-115 Type Ii Ssntds

Determination of Uranium and Thorium Contents in Various Material Samples of Morocco Using a New Monte Carlo Code for Evaluating the Mean Critical Angle of Etching of the Cr-39 and Lr-115 Type Ii Ssntds

The activity concentrations of radionuclides 226Ra, 232Th and 40K of soil samples in the case of Metekel Zone, Ethiopia

In this paper, we have studied the concentration levels and corresponding radiological hazard indices of natural radioactive elements such as radium-226, thorium-232, and potassium-40 in soil samples collected from Metekel Zone, Ethiopia. We have determined the concentration levels with the help of gamma ray spectrometry. Accordingly, we obtained the average values for radioactive concentrations of radium, thorium, and potassium to be 64 Bq/kg, 70 Bq/kg, and 330 Bq/kg, respectively. The radiological hazard has been also determined from the pertinent concentration levels of radium, thorium and potassium isotopes. Therefore, we obtained that the radioisotopes have heterogeneous distribution which must be caused by the nature and types of the soil in the area where this investigation was conducted for.

Characterization of rare earth elements (REE) from industrial REE waste resources

Water Leach Purification (WLP) residue is a Naturally Occurring Radioactive Material (NORM) that is composed of iron phosphate. The Malaysian government has classified WLP residue as a radioactive material since the thorium (Th) concentration surpassed the 1000 Bq/kg standard. The sample has been chemically and physically characterized by using X-ray fluorescence (XRF), inductively coupled plasma mass spectrometry (ICP-MS), scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) and particle size distribution analysis (PSD). Based on XRF result, the sample is made up of Fe2O3 (32 %) and P2O5 (20.8 %). The rare earth analysis using the ICP-MS technique revealed a total quantity of rare earth (ΣRE) of 88367 ppm with gadolinium (Gd) as the most abundant element. This data and information from the characterization data will be used in the next process which is REE extraction process.

Geophysical interpretation methods' improvement of Bilche-Volytska zone of Pre-carpathian foredeep complex geological cross-sections' comprehensive research results

The article considers the problem related to the ambiguity of logging results, which is reflected in the reduction of the efficiency of certain interpretive methods, and as a consequence of oil and gas reservoirs omission. In this regard, the analysis of the results of gamma logging, spontaneous polarization methods, nuclear magnetic logging, were conducted. The received information of experimental researches of cores, has allowed establishing the reasons of distortion of radioactive and electric logging indications which considerably influence on size of radioactive and electric fields intensity. In addition, the efficiency of gamma-spectrometric method and nuclear magnetic resonance is substantiated. It is established that the matrix of rocks of Neogene sediments contains minerals of sulfides, oxides, which include iron, copper, aluminum. That determines the electronic conductivity of oil and gas saturated layers. Different from clarke, the contents of uranium, thorium and potassium were determined in the matrix of the above mentioned rocks according to the results of gamma spectrometry. These elements affect the value of the natural intensity of hydrocarbon-saturated rocks’ radioactive field. A method for determining the carke content of radioactive isotopes of uranium, thorium and potassium with the calculation of their ratio was developed to unambiguously assess the nature of the increased radioactivity of Neogene rocks. The results justify the use of the latest technological methods for gamma spectrometry and nuclear magnetic resonance in the allocation of productive rocks. Well research by NMR can be effectively performed with the help of NMLE-3 (nuclear magnetic logging equipment), and gamma spectrometry can be conducted with the help of SGSM-2.