The photogeological study of small areas with particular reference to the use of the mini-drone.

Initially a variety of established photo-interpretation methods have been applied to the study of mineralised areas and to the mapping of geological features, hydrographic surveys and miscellaneous investigations of small sites using commercially available black and white, colour and infra-red false colour photography. In addition the potential of multi-spectral and infra-red linescan imagery has been investigated. A method using a radio-controlled mini-drone has been developed for the acquisition of imagery covering small areas for base mapping and interpretation purposes. The imagery obtained has been found to be of acceptable quality and may be used either to supplement the conventional imagery particularly where only black and white cover is available, or to carry out a mini-drone survey in its own right. Microdensitometry and statistical analysis of the image data has been carried out together with computer graphics to assist in the interpretation and display of results. The work demonstrates the value of utilising imagery of all types and at all scales for geological interpretation purposes and the flexibility of relatively simple and cheap data acquisition and image processing facilities for limited areas. Although successful in exposed situations the problems of interpretation of vegetated and soil covered terrain in the United Kingdom are highlighted, but nevertheless a significant increase in detectability of subtle features in mineralised zones in difficult terrain, has been achieved using techniques such as microdensitometry.