Modelling Of The Basement Surface Of Siwa-Qattara Depression Area, Northern Western Desert Of Egypt

Abstract

Modelling study of the basement surface of Siwa-Qattara Depression area was done through the calculation of basement depth for 62 selected points using gravity interpretation methods. The constructed basement relief map is justified and confirmed by data of many reference drilled wells in the study area. It is delineated by different systems of faults of different ages, origins and tectonisms. A mathematical model was assumed as 5th degree polynomial equation whose coefficients were calculated applying the least squares method. Computation was carried out by using I.B.M. of the National Institute of Oceanography and Fisheries, Alexandria. The 3rd and 4th degrees polynomials were also tried for the sake of justification. The best fitting of the constructed gravity basement depth map is found to be expressed by the 5th degree polynomial. The mathematical model of the basement surface of the study area as well as the computed deviations between the interpreted and the modelled depths are of great importance and significance in evaluating and selecting drilling locations for hydrocarbon exploration in this part of the Northern Western Desert of Egypt.