Mansoura University Faculty of Science, Damietta branch Geology Department New Damietta Egypt
haboelkhair@mans.edu.eg
Dr. Hatem Aboelkhair was a senior Geophysicists in Uranium exploration at Nuclear Materials Authority of Egypt from 1994-1999. He is now senior lecturer in Geophysics at Mansoura University where he teaches Geophysics and Remote Sensing. Recently he worked at Geological Survey of Japan (GSJ) for one year in Remote sensing research group from 2008-2009.
Abstract: Airborne geophysical surveying is a remote sensing technique that is used for measuring the variation of different physical or geochemical parameters of the earth such as distribution of magnetic minerals, electric conductivity and radioactive element concentration.
Bahariya Oases area is located in the northern part of the Western Desert of Egypt It is situated almost 160 km to the west of the Nile Valley. The Bahariya Oases area displays a special importance in recent years due to the discovery of economic iron ore deposits in El-Gedida and Nasser areas as well as the discovery of petroleum in economic quantities in a nearby area. The present book aims essentially to the analysis and interpretation of the aerial gamma-ray spectrometric and magnetic survey data recorded over the Bahariya Oases area. These analyses and interpretations are mainly employed to produce radioelement mapping, define mineral and petroleum exploration potentiality as well as environmental monitoring.
Abstract: In situ gamma spectrometric measurements have been performed to characterise the natural radiation that emitted from the stream sediment feldspars in Wadi El Missikat and Wadi Homret El Gergab, Eastern Desert, Egypt. The measurements of potassium (K, %), equivalent uranium (eU, ppm) and equivalent thorium (eTh, ppm) were converted into specific activities and equivalent dose rate. The average specific activities were 1402 Bq kgâ1 for K, 113 Bq kgâ1 for eU and 108 Bq kgâ1 for eTh in Wadi El Missikat, while they were 1240, 104 and 185 Bq kgâ1 in Wadi Homret El Gergab. The calculated outdoor average effective dose rates was 1.1 mSv yâ1 in wadi El Missikat and 1.3 mSv yâ1 in Wadi Homret El Gergab. The terrestrial-specific activities and effective dose rate levels of the natural radioactivity in the two areas lie within the international recommended limits for occupational feldspar quarry workers. On the other hand, these results indicated that irradiation is higher than the allowable level for members of the public. Therefore, quarrying the feldspar sediments from these locations as ceramic raw materials may yield an undesired impact on the environment, especially through the indoor applications.
Abstract: Two significant airborne gamma ray spectrometic (AGRS) statistical parameters, i.e., the arithmetic mean and the standard deviation, were computed for all lithologic units and formations of the Bahariya Oases area, Northern Western Desert, Egypt. The results ascertain that the maximum AGRS values are associated with sabkha sediments, Bahariya Formation, basalt flows and sand dunes. The intermediate values are correlated with El-Heiz, El-Hefhuf, Qazzun and Naqb formations. The minimum values are connected with Khoman Chalk and El-Hamra formations. The AGRS records were found to vary from one type of rock to another and to some extent between units of the same rock type too. On the aerial total-count (TC) radiometric maps, the records change from 6.2 to 69.36 μR/h. On the potassium map, the values range from 0.05% to 4.35%. On the equivalent uranium (eU) and equivalent thorium (eTh) maps, the records oscillate from 0.12 to 7.4 ppm and from 0.28 to 8.4 ppm, respectively. Concerning the Bahariya Oases area, the calculated arithmetic mean natural dose rate values originating from the terrestrial gamma radiation were found to range from 0.14 to 0.26 mSv/year and where the maximum value attains 0.62 mSv/year. These values remain on the safe side and within the maximum permissible safe radiation dose without harm to individuals, with continuous external irradiation of the whole body.
Abstract: ASTER level 1B (radiance at the sensor) TIR-bands and level 2B04 (surface emissivity) data were analyzed to detect four of 14 rare-metal-enriched albite granite, which are classified as I-type magnetite-series (G3 type) granites in the Central Eastern Desert of Egypt. Analysis of the shapes of laboratory emissivity spectrum
of albite granite samples measured by portable emission spectrometer and albite mineral spectra from ASTER spectral library at the website of JPL of NASA showed that, albite granite samples has a higher emissivity in bands 12, 13 and 14 than in bands 10 and 11. To identify and map this type of granite, Quartz Index, as well as band ratios, band ratio combination and band combinations were used, based
on the shapes of the analyzed emissivity spectrum of albite granite samples and albite mineral. The Quartz Index (QI) was high for quartz-rich/feldspar poor rocks and was low for K-feldspar or gypsum-rich rocks. Albite rich granites were detected as dark pixels in the QI image. The proposed band ratio b12/b11 clearly identified the albite granite bodies as dark regions. False color images of band combination of
14:12:10 and 12:13:11 in R:G:B clearly mapped the albite granite bodies as light brownish yellow and light greenish regions respectively. A new ASTER colored composite band ratio combination b12/b13:b11/b12:b14/b13 as R:G:B is applied successfully for mapping albite granite in the study area. This new combination clearly separated albite granite as pinkish magenta color. An ASTER scene covering the study area acquired on a different date was used to determine the effect of atmospheric and surface temperature conditions on the ratio and the mathematical band operation. The results indicated no significance differences.
Abstract: A new exploration method was developed by Saunders et al. (1993) which uses surface and aerial gamma-ray spectral measurements in prospecting for hydrocarbon accumulations in stratigraphic and structural traps. This method was applied on the recorded aerial gamma-ray spectrometric survey data of the Bahariya Oasis area, Northern Western Desert, Egypt. The study area displays a special importance in recent years, due to the discovery of economic iron ore deposits in Algedida and Nasser areas as well as petroleum in economic quantities in a near-by area. The application of this method on the survey data led to the identification of nine zones along nine profiles over the study area, which show valid anomalies. These zones may define possible subsurface hydrocarbon deposits within the area under consideration.
