New geophysical logging techniques for practical problem solving at complex hydrogenetic uranium deposits

Abstract

In-situ uranium recovery features high economic efficiency and low environmental impact as compared with other uranium production techniques. The article presents the experimental results on the application of new geophysical logging methods at a uranium deposit of hydrogenetic type. Complex hydrogenetic uranium deposits have a nonuniform lithology, varied permeability and alternation of permeable and water-resistant rocks. The development of such deposits is often complicated by a number of factors affecting the production process. The common methods of geophysical research in wells provide insufficiently reliable information about the geological structure of interwell space. As a result, it is difficult to control and monitor the production process, which can lead to inefficient consumption of chemical reagents, undesirable leakage beyond the limits of production blocks, incomplete extraction of uranium reserves, etc. To solve the problem of insufficient studies of interwell space, the method of radiowave geointroscopy was tested. This method is based on the measurement of electrical resistance. The tests were carried out in two stages, during the periods of high-rate production. By comparing the measurement results in different dimensions, the electrical resistance maps were plotted. The interpretation of the measurement results made it possible to obtain reliable data on the actual distribution of solutions in the interwell space in a given period of time, to identify areas of excessive concentrations of solutions (stagnant zones), to assess acidification dynamics in production blocks, and to delineate potentially difficult areas of the blocks.