الفهرس 
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Abstract
The present research work deals essentially with the integrated analyses and interpretation of the airborne gammaray spectrometric and magnetic survey data over the Bahariya Oases area, Northern Western Desert, Egypt. These analyses and interpretations are mainly devoted towards geological mapping, petroleum and mineral (with special emphasis on the radioactive mineral deposits) exploration as well as environmental monitoring. The aerial gammaray spectrometric records vary from one type of rock to another and to some extent between units of the same rock type too. On the aerial totalcount (T.C.) radiometric maps, the records vary from 6.2 to 69.36 (So(BR/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 vary from 0.12 to 7.4 ppm and from 0.28 to 8.4 ppm respectively. According to visual inspection of the aeromagnetic map, four separate magnetic zones of various magnetic characteristics were distinguished on the basis of the variations in amplitude, trend pattern and grouping of anomalies. Two main aeroradiospectrometric statistical parameters, i.e., the arithmetic mean ( ) and the standard deviation (S) were computed for all geologic units of the Bahariya Oases, Northern Western Desert, Egypt. The results ascertain that the maximum values of aeroradiospectrometric data are associated with sabkha, Bahariya Formation, basalt and sand dunes. The intermediate values are correlated with ElHeiz, ElHefhuf, Qazzun, and Naqb formations. The minimum values are connected with Khoman Chalk and ElHamra formations. A new exploration method was developed using aerial gammaray spectral measurements to prospect for petroleum in stratigraphic and structural traps. This method was applied on the recorded aerial gammaray spectrometric survey data of the study area. The application of this method has led to identify nine zones along nine profiles over the study area which have valid anomalies. All the nine profiles are located around the Sandstone Hills structural belt, which is an ENEoriented monocline most probably underlain by deepseated ENEoriented fault. These zones might indicate a prospective petroleum accumulation in the Bahariya Oases area, Northern Western Desert, Egypt. The computed arithmetic mean values of the exposure and the dose rates for the individual geologic units shows that the mean natural dose rates from the terrestrial gammaradiation range from 0.14 to 0.26 mSv/y and the maximum value attains 0.62 mSv/y. These values remain on the safe side and within the maximum permissible safe radiation dose without harm to the individual, with continuous external irradiation of the whole body. Two depth techniques determination (manual and 3DEuler deconvolution) has been applied to the magnetic data to identify and make depth estimation for a wide variety of geologic structures data of the two previous methods of depth determination techniques, showed that, the depth to basement range between 0.284 km and 6 km. The maximum depth was recorded at the eastern part of the study area, where the minimum depth was recorded at its central part. Statistical analysis of the trends of the nearsurface and the deepseated lineaments indicating structural features were quantitatively carried out using the statistical rose diagram technique.This analysis shows the clearly relationship between the deepseated, nearsurface (shallow) and surface structures forming the Bahariya Oases area, Northern Desert, Egypt. The obtained results indicates the existence of seven major trends, as follows: