LOW-ALTITUDE UNMANNED AEROMAGNETIC SURVEY IN MANAGEMENT OF LARGE-SCALE STRUCTURALGEOLOGICAL MAPPING AND PROSPECTING FOR ORE DEPOSITS IN COMPOSITE TOPOGRAPHY. Part 2
The article provides an overview of techniques and procedures used in the low-altitude unmanned aeromagnetic survey technology developed by the authors. The main procedure methods are aimed to develop a digital terrain model and prepare flight missions taking into account the relief flow; to pre-verify a flight mission; to perform measurements and data post-process ing. A digital terrain model can be developed based on a combination of global elevation coverage data and conditioned topo graphic maps or preliminary aerial imageries. A flight mission is verified by a lighter Unmanned Aerial Vehicle (UAV) equipped with a camera. The flight mission planner tool is described in the previous part of this article. The authors present survey results obtained by testing the UAV-magnetic exploration technology in solving prospecting and evaluation problems on the black shale type gold objects located within the Baikal-Patom Highland. The technology was tested in adverse weather conditions and com posite topography. Some of the explored objects presented a real challenge to magnetic survey due to low contrast of the mag netic field, which required a high absolute precision and sensitivity of magnetometers. The results obtained by the new unmanned method have been compared with the data of traditional pedestrian survey. It is shown that in complex environment the UAV technology produces good conditioning data, their quality is even better than that of the ground surveys. Productivity and eco nomic efficiency of the UAV magnetic survey technology are therewith significantly higher, the cost is about two times less, and there is no need for deforestation. As a result, we draw a conclusion that it is possible and advisable to replace the traditional pedestrian magnetic prospecting with the new unmanned technology, at least in the surveys of scales from 1:10 000 to 1:1000.