[en] The suitability of spectrometric backscattered gamma-gamma well logging measurements to predict lead and zinc metal equivalent content is demonstrated. A centralised tool employing a gamma-ray source of very low radioactivity (1.8 MBq) is used. The logging tool is tested using ¹³³Ba and ¹³⁷Cs sources with a 37 mm (diameter)x75 mm NaI (TI) scintillation detector. Five source-to-detector configurations were analysed for 18 geophysical models, 13 of which had a borehole diameter of 130 mm and the other 5 had a borehole diameter of 160 mm. Regression analysis on the laboratory logging data for each configuration in order to establish the calibration equation for a lead (Pb) and zinc metal equivalent (ZME) prediction is carried out. The optimum configuration for the logging probe using a ¹³³Ba source was determined to be 52 mm source-to-detector spacing. This configuration gives the best results for both Pb and ZME grade. The rms deviations for Pb and ZME were 0.33 and 2.3%, respectively. The optimum configuration for the logging probe using a ¹³⁷Cs source was determined to be 64 mm source-to-detector spacing. This configuration gives the best results for both Pb and ZME grade. The rms deviations for Pb and ZME were 0. 3 6 and 2.2 %, respectively

[en] A stockpile probe based on backscattered gamma-gamma-ray technique was tested for the determination of coal ash. A centralized tool employing a gamma-ray source of very low radioactivity (1.85 MBq) was used. This logging tool was tested using ¹³⁷Cs and ¹³³Ba sources with a 37 mm (diameter) by 75 mm NaI (TI) scintillation detector. Ten source-detector configurations were analyzed using ¹³⁷Cs, and another nine source-detector configurations are analyzed, using ¹³³Ba source, both for four geophysical models, having a borehole diameter of 90 mm. Regression analysis on the laboratory logging data for each studied configuration was carried out in order to establish calibration equations for ash prediction. The optimum configuration for the logging stockpile probe using ¹³⁷Cs source was determined to be 80 mm source to detector spacing, and 80 mm iron thickness shielding. This configuration gives the best results for ash prediction. The root mean square (rms) deviation for ash is 1.52%. The optimum configuration for the logging stockpile probe using ¹³³Ba source is determined to be 85 mm source to detector spacing, and 50 mm iron thickness shielding. This configuration gives the best results for ash prediction, where the rms deviation for ash is 1.47%

[en] Factor analysis technique is proposed in this research for interpreting the combination of nuclear well logging, including natural gamma ray, density and neutron-porosity, and the electrical well logging of long and short normal, in order to characterize the large extended basaltic areas in southern Syria. Kodana well logging data are used for testing and applying the proposed technique. The four resulting score logs enable to establish the lithological score cross-section of the studied well. The established cross-section clearly shows the distribution and the identification of four kinds of basalt which are hard massive basalt, hard basalt, pyroclastic basalt and the alteration basalt products, clay. The factor analysis technique is successfully applied on the Kodana well logging data in southern Syria, and can be used efficiently when several wells and huge well logging data with high number of variables are required to be interpreted. - Highlights: • Statistical factor analysis technique is proposed for interpreting nuclear and electrical well logging data in basaltic environment. • New rotated scored logs are established and interpreted at the light of available geological data. • The established score lithological cross-section differentiates between four different kinds of basalt

[en] Fractal theory modeling technique is newly proposed in this research for interpreting the combination of nuclear well logging, including natural gamma ray, density and neutron-porosity, and the electrical well logging of long and short normal, for establishing the lithological cross section in basaltic environments. The logging data of Kodana well, localized in Southern Syria are used for testing and applying the proposed technique. The established cross section clearly shows the distribution and the identification of four kinds of basalt which are hard massive basalt, hard basalt, pyroclastic basalt and the alteration basalt products, clay. The concentration- Number (C-N) fractal modeling technique is successfully applied on the Kodana well logging data in southern Syria, and can be used efficiently when several wells with much well logging data with a high number of variables are required to be interpreted. - Highlights: • Testing and applying fractal theory modeling technique on the nuclear and electrical well logging data of Kodana well in Southern Syria. • Using Concentration-Number (C-N) approach while applying fractal geometry. • Differentiating between four kinds of basalt. • Establishing the lithological section of the studied well.

[en] Highlights: • Apply multifractal Concentration-Number (C-N) modeling approach to Airborne Gamma Spectrometry (AGS) data. • AGS technique has been applied for uranium exploration in Syria. • Four radioactive parameters were recorded, T.C, eU, eTh, and K%. • Log-log plots indicate the presence of different uranium anomaly ranges. • Radioactive ranges have been verified by field geology and surface spectrometric gamma sample rocks analysis. - Abstract: Multifractal Concentration-Number (C-N) modeling approach has been developed and applied to Airborne Gamma Spectrometry (AGS) data related to Area-3, Northern Palmyrides, Syria. The application of the multifractal approach basically aimed at separating uranium anomalies from background. The AGS technique has been applied for uranium exploration in Syria, where four radioactive parameters were recorded, T.C, eU, eTh, and K%. Log-log plots practiced on those radioactive variables indicate the presence of different uranium anomaly ranges. Those radioactive ranges have been verified and controlled by both geology field and surface spectrometric gamma sample rocks analysis. The area range of 5.37–13.20 eU includes uranium concentration more than 120 ppm, The area range of 2.95–5.37 eU includes uranium concentration of 50 ppm, and the area range of 1.40–2.95 eU includes uranium concentration of 7 ppm. Positive correlation has been consequently found between radioactive anomalous eU ranges and uranium concentrations. Such correlation indicates the importance of multi fractal approach to be extensively used as a fractal analysis-smart sampling tool in phosphate and uranium prospecting programs, where a positive correlation between phosphate content, radioactivity and uranium concentration exist.

[en] A stockpile probe based on backscattered gamma-gamma-ray technique was tested for the determination of coal ash. A centralized tool employing a gamma-ray source of very low radioactivity (1.85 MBq) was used. This logging tool was tested using ¹³⁷Cs and ¹³³Ba sources with a 37 mm (diameter) by 75 mm NaI (TI) scintillation detector. Ten source-detector configurations were analyzed using ¹³⁷Cs , and another nine source-detector configurations are analyzed, using ¹³³Ba source, both for four geophysical models, having a borehole diameter of 90 mm. Regression analysis on the laboratory logging data for each studied configuration was carried out in order to establish calibration equations for ash prediction. The optimum configuration for the logging stockpile probe using ¹³⁷Cs source was determined to be 80 mm source to detector spacing, and 80 mm iron thickness shielding. This configuration gives the best results for ash prediction. The root mean square (rms) deviation for ash is 1.52%. The optimum configuration for the logging stockpile probe using ¹³³Ba source is determined to be 85 mm source to detector spacing, and 50 mm iron thickness shielding. This configuration gives the best results for ash prediction, where the rms deviation for ash is 1.47%

[en] Nuclear well logging, including natural gamma ray, density, and neutron-porosity techniques are used with electrical well logging of long and short normal techniques to characterize the basaltic areas largely extended in Southern Syria. Statistical analysis approach with the threshold concept has been adapted for such characterization, where four kinds of basalt have been identified: very hard basalt, hard basalt, fractured basalt, and basalt alteration products. The spectrometric gamma technique has also been applied on the retrieved rock samples in order to determine the radioactive content (eU, eTh, and K%) of the basaltic section in the study area. No radioactive anomalies have been detected, the radioactive values are normal and in the expected range.

[en] Highlights: • Airborne γ-ray spectrometry data are used to evaluate and map the radioactive heat production in the Syrian desert (Area-1). • Fractal technique combined with concentration-number model (C-N) is used to map T.C, eU, and HP in Area-1. • Lithological scored phosphatic units are characterized by higher HP than other lithological units in the study region. - Abstract: Radioactive heat production (HP) in the Syrian desert (Area-1) is estimated by using the available data of aerial spectrometric gamma technique. The HP is separately well characterized for 10 geological units, which are identified on the already established Area-1 scored map. Fractal technique combined with concentration-number (C-N) model and log-log graphs is used to map total radioactivity, equivalent uranium, and HP in Area-1. The HP in Area-1 varies between a minimum of 0 and a maximum of 7.23 μw/m³, with an average of 0.584 μw/m³ and a standard deviation of 0.341 μw/m³. The lithological phosphatic units A, B, C, and D are characterized by a higher HP than their surrounding units, because of their richness in uranium concentrations.

[en] Total gamma ray method has been used in some boreholes in Khnefis ores (a phosphate mine). The aim of the study was to determine the thickness and spreading of the phosphate beds in this area. Many anomalously ratio active zones have been identified, which reflect the P₂ O₅ and uranium content of the phosphate. The obtained data has been treated by using a developed Rock were-Logger. (author). 2 refs., 11 figs.,

[en] Highlights: • Natural gamma-ray (GR) well-logging technique is used to evaluate heat production (HP) in the phosphatic Khneifis region in Syria. • Seven natural GR logs are used to compute the HP along them. • Bucker and Rybach method is applied to estimate the HP from GR logs. • Fractal concentration-number (C-N) model is used to map GR and HP of the Khneifis region. • High values of HP of more than 5 μw/m³ are related to phosphatic layers enriched by uranium. - Abstract: Natural gamma-ray (GR) well-logging technique is used to estimate the radioactive heat production (HP) parameter as a function of depth, in the phosphatic Khneifis deposit in Palmyrides region in Syria. Seven available drilled wells with their natural GR records are used to characterize and estimate the HP magnitude in the study region. The analysis of 2660 measured points in those wells shows that HP varies between a minimum of 0 and a maximum of 7.97 μw/m³, with an average of 1.33 μw/m³ and a standard deviation of 1.68 μw/m³. Multi-fractal approach with the use of concentration-number (C-N) model and log–log plots is originally proposed and used as a new approach for characterizing the HP variations and isolating different HP populations in the study region. The high HP ranges are mainly related to the phosphatic layers, relatively enriched by uranium concentrations, comparing with their surroundings.