Image-Based Spatial Information Systems for Geologic Logging
Hao Li, Xiaomin Jia, Yueqin Niu and Rui Wang
College of Civil Engineering, Hohai University, 1 Xikang Road, Nanjing 210098, China
Abstract. The present geologic logging is still primarily accomplished by the manual sketch and field surveying, this operating type does not adapt to the process of practical productive forces and the fast response of informationization construction on spot. In order to realize the digitalization of collection, processing, management and analysis in engineering geology, the author has researched and used the application method of measuring non-metric camera, it can reduce the request of special equipment and professional skill in image-based geologic logging. Based on the research, the author has studied and developed the image-based spatial information system used in engineering geologic logging, and has constructed technology system of digital logging based on the information system. Image-based spatial information system for geologic logging is a special information system, which grounds on the theory of photogrammetry, makes good use of the techniques of close-rang photogrammetry, digital image processing and GIS, and is characteristic of the interdisciplinary cross. The main functions of the system including the automatic creation of the stretched image map of logging objects, digital plotting of structure feature, Image-based measurement of the structural plane’s attitude, management and query of logging attribute and graphic data, output of AutoCAD drawing etc, besides, it can offer the image production of geology reconnaissance for engineering construction. Theoretical precision and result of practical application show that, in image-based geologic logging, the mean square error of position of tunnel and well are less than 0.2m, of slope and foundation pit are less than 0.3m. The mean square error of measuring structural plane’s attitude is less than 0.2º, all of these have met the requirement of engineering geologic logging specifications. The system has accomplished the transformation from manual work to computer-assisted work in engineering geologic logging, and also has generally improved the technical levels and the working efficiency in aspect of data collection, processing, management and application. This paper elaborates some main points of image-based spatial information system for geologic logging, including the system's structure and function module design, the principle of work and spatial information processing algorithm, method of precision estimation and analysis of application instance, etc.
Keywords: image-based spatial information system, engineering geologic logging, photogrammetry, precision, non-metric image
In: Wan, Y. et al. (eds) Proceeding of the 8th international symposium on spatial accuracy assessment in natural resources and environmental sciences, World Academic Union (Press).