Využití statistických a geostatistických metod pro hodnocení vlivu těžby a úpravy antimonových rud v milešovském revíru.

Abstract

The thesis deals with the modern processing of data on the disposal sites of mining waste at Milešov (district Příbram) using statistical and geostatistical methods. In the Milešov neighborhood has been mined and processed antimony ores for about twenty years in the second half of the 19th century. After this period there left large heaps and small sludge pond. In 1988 was this locality sampled and the residual reserves of gold and antimony were then calculated here. After 2010, this site was evaluated in accordance with the Mining Waste Act. Arsenic and antimony were identified as the major harmful elements and so-called hazardous mining waste facilities were defined here based on the calculated hazard index (HI). In the introduction is summarized basic information about the area of interest, geological situation, geomorphology, climatic, hydrographic and hydrogeological conditions. The position of the site is also mentioned in relation to the surrounding protected areas and protection zones. The history of local mining is descripted in details and some inaccuracies have been corrected. The benefit is also a detailed review of the available materials, which contents new, still not used documents. The Milešov locality was visited during the work several times for photographic documentation and sampling. Typical samples of local ores, slags and processing sands were analyzed on an electronic microscope and the results were compared with previously detected mineralogical analyzes. Theoretical process of creation of digital models of spatial elements distribution for the heap and the tailing pond is mentioned in its own chapter. Next detailed steps are described subsequently and they include the creation of a digital terrain model, the problem of the original surface reconstruction, the verification and modification of the input data, which were the original results of the analyzes made in 20th century. Based on these works, the grids of studied elements were created both with visualization of the spatial location of the input data. Subsequently, data were statistically processed and geostatistical structural analysis was performed. Then, digital modeling of the spatial distribution of the monitored elements followed using different methods. Specifically, there were chosen inverse distance weighting (IDW) interpolations in variants of parameters of anisotropy ellipsoid and data selection at 25 m*25 m*1 m and 50 m*50 m*2 m, the method of simple kriging and finally the geostatistical sequential Gaussian simulation (SGS). The new concept of interpreting the original archive data has made it possible to compare the effectivity of the current methods with previously used “vertical cut” method. Using a newly developed program called Milesov, it was possible to make new estimates of the contents of monitored elements. The results showed their significantly higher volumes and more accurate and realistic localization in both bodies (heap and tailing pond). To implementation of the methodology of creation, visualization in 2D and 3D and the processing of digital models of the monitored parameters were used in addition to the above mentioned Milesov program, the software Voxler and Surfer by Golden software and SGeMS. Thanks to these processing, it is also possible to refine the existing conceptual model of the site and to give a much more accurate assessment of negative impacts on the surrounding environment and population.