Negligence of Geological Investigations Site Leading to Slope Failure Incidents: A Case Study From Saih Al Ahmar in Bidbid, Northern Oman

Abstract

This paper describes and analyzes a recent slope failure alongside Saih Al Ahmar water storage tank in Bidbid, and identifies the natural and induced causes of the landslide. Our analysis demonstrates that the landslide in Bidbid was the result of several combined factors: slope-forming materials, distribution of geological discontinuities and disturbance by human activities. Moreover, field observations, satellite imagery and geology of the study area indicate that the major factors which caused the landslide are the steep slope excavation along the developed tensional faults, the material in the slide ranging from talus deposits to interlayered peridotite and gabbro, cutting perpendicular to slope talus and removal of the toe of the slope. The slope failure and other stability concerns in the subsurface threatening the structural integrity of water storage infrastructure would not have arisen if the geology of the area had been carefully taken into account before the excavation phase. Landslide hazard assessment in the water tank area and its surrounding is necessary to manage the landslide risk. Proper measures should also be adopted to mitigate the impact and to avoid further failure in the slope already on the verge of movement by rainfall.