Geophysical and borehole investigations were carried out to explore the sites of subsurface buried cavities and related subsidence in Ar-Riyadh city, Kingdom of Saudi Arabia (KSA). Traditional ground probing practices were not adequately conducted in the city due to various reasons including lack of technology at a time, economic factors, the ambient general culture, and time constraints. Consequently, locations of near-surface buried hazardous cavities for proposed development projects in the studied area are essentially unknown. The geophysical studies are represented by the interpretation of ground penetrating radar (GPR) images, while the borehole investigations were done through five drilled boreholes (BHs). A good match between the results of the two methods has been found indicating the usefulness of radar techniques to identify the ground conditions prior to major engineering projects in karstic regions such as Ar-Riyadh. In addition to locating major cavities in a city underlain by limestone bedrock, crucial recommendations have been proposed to be implemented before and/or during the design and construction of major foundations in the area.

进行了地球物理和钻孔调查，以探索沙特阿拉伯王国 (KSA) 利雅得市的地下掩埋空洞和相关沉降的地点。由于各种原因，包括一次缺乏技术、经济因素、周围的一般文化和时间限制，传统的地面探测实践未能在该市充分进行。因此，研究区域内拟议开发项目的近地表埋藏危险洞穴的位置基本上是未知的。地球物理研究以探地雷达 (GPR) 图像的解释为代表，而钻孔调查是通过五个钻孔 (BH) 完成的。已经发现两种方法的结果之间的良好匹配表明雷达技术在喀斯特地区（例如 Ar-Riyadh）的重大工程项目之前识别地面条件的有用性。除了在石灰岩基岩下的城市中定位主要空洞之外，还提出了在该地区主要基础的设计和施工之前和/或期间实施的重要建议。