Research on Oblique Aerial Photography and its Application in Detection of Hidden Geological Hazards

The Wu Gorge section of the Three Gorges Reservoir is prone to landslides and collapses of rock masses, which poses considerable threats to the transportation safety along the watercourse of Yangtze River. The oblique aerial photography technique can accurately present the profile and texture information of the observed objects, which can provide data for early detection of geological hazards. In this study, the technique of oblique aerial photography was analyzed in depth, and the obtained oblique aerial photographs were combined with the position and orientation system (POS) data and the ground control points to build a three-dimensional model, and a geological disaster evaluation model was built based on such factors as geological conditions, landform, and hydrological conditions for geological hazard evaluation. Meanwhile, indoor interpretation and fieldwork surveys were performed to summarize the patterns of development and distribution of geological disasters, identify the major contributors to geological disasters in the study area, and master the characteristics of liability of the study area to geological disasters and hidden hazards.