RELATION OF THORIUM- NORMALIZED AERIAL RADIOSPECTROMETRIC DATA AND PETROLEUM ACCUMULATIONS, BIR EL-MELLAHA AREA, CENTRAL EASTERN DESERT, EGYPT.

Over the past 25 years there has been progressive development in understanding the relation of aerial and surface radiometric measurements to subsurface petroleum accumulations. The data from many recent gamma-ray spectral surveys have confirmed the presence of characteristic anomalously low potassium and higher uranium gamma-ray levels over a majority of oil and gas fields tested.
A new exploration method has been developed by Saunders et al., 1993 using surface and aerial gamma-ray spectral measurements in prospecting for petroleum in stratigraphic and structural traps. Bir El-Mellaha area, Central Eastern Desert, Egypt, was selected to apply this method on its recorded aerial gamma- ray spectrometric survey data due to its situation in close connection with the Gulf of Suez, which represents one of the important sites of oil production in Egypt.
The three variables (eU, eTh, and K) registered for the whole study area, in the form of three contour maps, were digitized along the flight paths every 1.0 km. The DRAD arithmetic means plus three standard deviations for the data set were computed. The application of this method on the survey data led to the identification of nine zones along six profiles over the study area, which shows valid anomalies. These zones may define possible subsurface hydrocarbon bearing deposits within the area under consideration.