Mapping of Bedrock Using the High-Resolution Seismic Reflection Technique at Wadi Al Dawasir Region, Saudi Arabia

Abstract

The study area is located between Wadi Al Dawasir and Aflaj cities, and about 690 km south of Riyadh city. The investigated area is found within the Wadi Tathlith quadrangle. About two thirds of the quadrangle is underlain by basement rocks of the Arabian Shield, much of it consists of an almost flat pediment surface. The remaining part of this quadrangle is in the southwest is underlain by almost horizontally bedded Phanerozoic sedimentary rocks. Wadi Al Dawasir Area forms part of the interior homocline structural province Al-Faifi (2005). The study location is divided into four sites (Fig. 1). Seismic methods have been widely used in detecting and mapping subsurface features, especially the layered sedimentary sequences in search of oil and gas reservoirs (Burger et al. 1992). Advantages of seismic methods over other geophysical techniques are due to their high accuracy, high resolution, deeper penetration, and the amount of information that can be extracted including mapping of the structures, faults, and compactness of various layers Sheriff and Geldart (1995). Recently, these methods, including the high-resolution seismic reflection method, have been applied to map shallow subsurface structures, depth of water tables, and identification of engineering related problems Kearey and Brooks (1984). Since all the engineering and environmental problems are located at shallow depths (near surface), seismic reflection method is an excellent choice to achieve high-resolution images from this domain. Keeping in view the usefulness of this method, four high-resolution seismic reflection profiles have been conducted in the study area. The main objective of this study is to provide estimates of the depth to bedrock and in detection the geological faults.