scholarly journals Radiometric Surveys for Detection of Uranium in Dhofar Region, Sultanate of Oman

2019 ◽  
Vol 24 (1) ◽  
pp. 36
Author(s):  
Narasimman Sundararajan ◽  
Bernhard Pracejus ◽  
Salah Al- Khirbash ◽  
Talal Al-Hosni ◽  
Ala Ebrahimi Ebrahimi ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Radioactive Decay ◽  
Sampling Interval ◽  
Uranium Mineralization ◽  
Gamma Ray Spectrometry ◽  
Sultanate Of Oman ◽  
Near Surface ◽  
The World ◽  
Uranium Exploration ◽  
Proterozoic Basement

The Proterozoic basement of the Dhofar region of the Sultanate of Oman might be considered as a potential source of Uranium mineralization like other Proterozoic basins of the world, which collectively contribute 30%-40% to the global production.  Uranium exploration assumes great importance in this part of the world and therefore geochemical and geophysical exploration for Uranium was initiated.  Initial, random sampling of the study area with Gamma ray spectrometry as well as in situ XRF (Xray Florescence) analysis indicated the presence of   around 30-40 ppm of Uranium. Since Gamma ray spectrometry results in the calculation of the heat produced during radioactive decay of Potassium (K), Uranium (U) and Thorium (Th) within the rocks in the study area, measurements were acquired along eleven traverses of varying length from 100-250 m at a traverse interval of 20 m and sampling interval of 10 m. Individual plots of the concentrations  of radioelements such as U, K and Th have shown favorable anomalous radioactive sources. Besides this, Uranium to Thorium (eU/eTh) and Uranium to Potassium (eU/K) ratio plots have been presented and the alteration zones associated with Uranium mineralization through all traverses have been identified. Further, the generated composite ternary image based on the combination of K, Th and U from Gamma ray spectrometry determines different relative amounts of radioelements and paves the way for deciphering the level of radioactivity in the study area. However, there seems to be no presence of strong Uranium anomalies in the near surface of the limited study area. As the study area is heavily faulted, the depth to concealed  subsurface fault structures  is  estimated to be around  64 m based on Hartley spectral analysis of total magnetic anomaly (line-6). 

scholarly journals Gamma-ray line measurements from supernova explosions

2017 ◽  
Vol 12 (S331) ◽  
pp. 157-163 ◽  
Author(s):  
Roland Diehl
Keyword(s):  
Supernova Remnant ◽  
Gamma Ray ◽  
Radioactive Decay ◽  
Line Emission ◽  
Gamma Ray Spectrometry ◽  
Young Supernova Remnant ◽  
Supernova Explosions ◽  
Cas A ◽  
Integral Data ◽  
Gamma Ray Telescopes

AbstractGamma ray lines are expected to be emitted as part of the afterglow of supernova explosions, because radioactive decay of freshly synthesised nuclei occurs. Significant radioactive gamma ray line emission is expected from56Ni and44Ti decay on time scales of the initial explosion (56Ni, τ ~days) and the young supernova remnant (44Ti,τ ~90 years). Less specific, and rather informative for the supernova population as a whole, are lessons from longer lived isotopes such as26Al and60Fe. From isotopes of elements heavier than iron group elements, any interesting gamma-ray line emission is too faint to be observable. Measurements with space-based gamma-ray telescopes have obtained interesting gamma ray line emissions from two core collapse events, Cas A and SN1987A, and one thermonuclear event, SN2014J. We discuss INTEGRAL data from all above isotopes, including all line and continuum signatures from these two objects, and the surveys for more supernovae, that have been performed by gamma ray spectrometry. Our objective here is to illustrate what can be learned from gamma-ray line emission properties about the explosions and their astrophysics.

URANIUM MEASUREMENT BY AIRBORNE GAMMA‐RAY SPECTROMETRY

Geophysics ◽  
1975 ◽  
Vol 40 (3) ◽  
pp. 503-519 ◽  
Author(s):  
R. L. Grasty
Keyword(s):  
Point Source ◽  
Gamma Ray ◽  
Radioactive Decay ◽  
High Energy ◽  
Gamma Ray Spectrometry ◽  
High Energy Radiation ◽  
Energy Radiation ◽  
Airborne Measurement ◽  
Decay Series ◽  
Different Depths

In the airborne measurement of uranium, window type gamma‐ray spectrometers are used and it is necessary to correct for scattered high energy radiation from thallium 208 in the thorium decay series. This radiation can be scattered in the crystal, in the ground, and in the air. A theory, analogous to the theory of radioactive decay, is developed; it can adequately explain the spectrum buildup in the uranium window for a point source of thorium oxide immersed to different depths in water and for a detector above the water. The theory is extended to predict the buildup as a function of altitude for detectors of different sizes and shows that errors in the airborne measurement of uranium can be, significant if no allowance is made for radiation scattered in the ground and in the air.

Introduction to the Special Issue on remote sensing

Geophysics ◽  
1987 ◽  
Vol 52 (7) ◽  
pp. 839-840
Author(s):  
Kenneth Watson
Keyword(s):  
Remote Sensing ◽  
Image Processing ◽  
Near Infrared ◽  
Gamma Ray ◽  
Mineral Exploration ◽  
Remote Sensing Data ◽  
Gamma Ray Spectrometry ◽  
Special Issue ◽  
Spectral Signatures ◽  
Uranium Exploration

In 1977, the first Special Issue on remote sensing published by Geophysics contained papers selected from two special sessions at the 45th Annual International SEG Meeting, October 12–16, 1975, in Denver, Colorado. That first Special Issue consisted of eight papers: four are primarily tutorial (image processing, spectral signatures in the visible and near infrared, microwave spectra of layered media, and factor analysis of gamma‐ray spectrometry), two involve structural interpretations with implications for mineral exploration and seismicity, and two examine multispectral reflectance data for detecting hydrothermal alteration and for uranium exploration. Although these papers indicate the importance of physical properties and models in the interpretation of remote sensing data, the studies were constrained by the instruments that collected the data and by the availability of image‐processing software. Circumstances have changed significantly in the intervening decade, as illustrated in recent review papers (Watson, 1985; Goetz et al., 1983) and demonstrated by the papers in this Special Issue.

scholarly journals Soil Gas Measurements of Radon, CO2 and Hydrocarbon Concentrations as Indicators of Subsurface Hydrocarbon Accumulation and Hydrocarbon Seepage

2021 ◽  
Vol 13 (7) ◽  
pp. 3840
Author(s):  
Marko Cvetković ◽  
Josipa Kapuralić ◽  
Marija Pejić ◽  
Iva Kolenković Močilac ◽  
David Rukavina ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Soil Gas ◽  
Gamma Ray Spectrometry ◽  
Hydrocarbon Accumulation ◽  
Near Surface ◽  
Migration Pathway ◽  
Sampling Points ◽  
Oil Seepage ◽  
Gas Measurements ◽  
Migration Pathways

Soil gas measurements of radon (222Rn), CO2, and hydrocarbon concentrations, as well as gamma-ray spectrometry, were conducted at two separate locations to estimate the measurement results for known locations of hydrocarbon accumulations in the subsurface and oil seepage on the surface. The aim of the study was to confirm the applicability of the method for identifying migration pathways (e.g., faults) and to detect possible seepages of hydrocarbons to the surface as well as to investigate possible health issue potential about the soil gas analysis results. Site A investigations were performed with a large number of sampling points to provide sufficient spatial coverage to capture the influence of subsurface lithologic variability as well as the influence of the migration pathway on the measured parameters. For the investigation of site B, sampling points were positioned to reflect the situation between the area above producing hydrocarbon fields and areas with no confirmed accumulation. The results presented show that it is possible to distinguish the near-surface lithology (gamma-ray spectrometry), characterize the migration pathway, and indicate the area of oil seepage at the surface. Areas above the known hydrocarbon accumulations generally have elevated radon concentrations and detectable heavier hydrocarbons with sporadic methane in soil gas, which contrasts with the lower radon levels and lack of detectable heavier hydrocarbons in soil gas in the area with no confirmed hydrocarbon accumulation in the subsurface.

Utilization of airborne gamma ray spectrometric data for geological mapping and radioactive mineral exploration of Gabel Umm Tineidba area, south eastern desert, Egypt

2015 ◽  
Vol 12 (2) ◽  
pp. 149-160 ◽  
Author(s):  
Tharwat H. Abdel Hafeez ◽  
Mohamed A. S. Youssef ◽  
Waheed H. Mohamed
Keyword(s):  
Gamma Ray ◽  
Mineral Exploration ◽  
Eastern Desert ◽  
Geological Mapping ◽  
Gamma Ray Spectrometry ◽  
Spectrometric Data ◽  
South Eastern ◽  
Uranium Exploration ◽  
Geological Information ◽  
Surface Geology

The present work utilizes airborne gamma ray spectrometric data in a trial to refine surface geology of igneous, metamorphic and sedimentary rocks, detect any radioactive mineralization at Gabel Umm Tineidba area South Eastern Desert, Egypt. The study area is covered by rock exposures ranging in age from the Precambrian to Quaternary. Airborne gamma ray spectrometry can be very helpful in mapping surface geology. This provides estimates of the apparent surface concentrations of the most common naturally occurring radioactive elements, such as potassium (K), equivalent uranium (eU) and equivalent thorium (eTh). This is based on the assumption that, the absolute and relative concentrations of these radioelements vary measurably and significantly with lithology. The composite image technique is used to display simultaneously three parameters of the three radioelement concentrations and their three binary ratios on one image. The technique offers much in terms of lithological discrimination, based on color differences and showed efficiency in defining areas, where different lithofacies occur within areas mapped as one continuous lithology. The integration between surface geological information and geophysical data led to detailing the surface geology and the contacts between different rock units. Significant locations or favourable areas for uranium exploration are defined, where the measurements exceed (X+2S), taking X as the arithmetic mean of eU, eU/eTh and eU/K measurements and S as the standard deviation corresponding to each variables. The study area shows the presence of fifteen relatively high uraniferous zone. In addition, the trend analysis based on the total count map and the published geological map shows that, most of the well-developed structural lineaments have NS, ENE, NNE and NNW trends.

The role of airborne geophysics for detecting hydrocarbon microseepages and related structural features: The case of Remanso do Fogo, Brazil

Geophysics ◽  
2012 ◽  
Vol 77 (2) ◽  
pp. B35-B41 ◽  
Author(s):  
Julia B. Curto ◽  
Augusto C.B. Pires ◽  
Adalene M. Silva ◽  
Álvaro P. Crósta
Keyword(s):  
Gamma Ray ◽  
Sedimentary Cover ◽  
Structural Features ◽  
Magnetic Data ◽  
Gamma Ray Spectrometry ◽  
Horizontal Gradient ◽  
Near Surface ◽  
Residual Values ◽  
Basement Structures ◽  
New Occurrences

The first direct indication of hydrocarbon occurrence in Remanso do Fogo area (Minas Gerais State, Brazil) was the existence of microseepages. However, Quaternary sedimentary cover in the area made the identification of new occurrences and associated controlling structures quite difficult. This study investigated the spatial distribution of hydrocarbon related gases in shallower to intrasedimentary depths in Remanso do Fogo area, using airborne gamma-ray spectrometry and magnetic data. The geophysical data were processed using techniques designed to suppress the influence of regional geological signatures. Known and possible new occurrences of microseepages were detected by mapping low residual potassium values and high uranium residual values in relation to potassium, termed as DRAD values, which resulted from the subtraction of potassium from uranium residual values, using a Thorium (Th)-normalizing approach. The validation of these occurrences was done based on existing gas geochemistry data in the soil. For the magnetic data, the amplitude of the analytic signal, combined with the total horizontal gradient of the subtraction between the 1200- and 400-meter upward continuations, enhanced the northwest–southeast and east–west magnetic lineaments, which are partially related to the microseepages and the drainage of the area. The distinction of near-surface and deep signatures also allowed the general identification of intrasedimentary and basement structures, which are potentially controlling the occurrences of seepages in the area.

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