Structural geology, groundwater, shear strength and blasting control pitwall stability at Equity Silver Mines, Houston, British Columbia. A geotechnical investigation of, these parameters was carried out in the Main Zone pit during the summer of 1984. The objective of the study was to develop a pitwall design based on geologic and groundwater conditions observed in each design sector. This thesis presents the results of the investigation; methods of improving stability by drainage and control blasting are also discussed. Information on structural geology was obtained by line mapping of existing berms. The discodat package of computer programs was used to process the structural data and to identify trends in orientation of discontinuities. Based on this information, the Main Zone pit was divided into ten design sectors, each sector having a consistent pattern of discontinuity orientations, rock type, groundwater conditions and pit wall orientation. Kinematically possible failure modes were identified in each design sector. Failure modes that were expected to present stability problems were analyzed to calculate factor of safety. Pit wall and berm face angles were then selected such that only a small number of potential failure modes will daylight. The stability evaluation has shown that it should be possible to increase pitwall angles by 5〫 in the west half of the pit. However, the data base in this area of the pit is presently limited because only a small number of berms are exposed. Therefore, additional line mapping will be required before the west wall design can be finalized. Groundwater will reduce pitwall stability, especially in the east half of the Main Zone pit. Multi-berm failures are very sensitive to groundwater conditions. A dewatering system should be installed in the Main Zone pit to minimize the possibility of such failures occuring. Wet blastholes dictate that expensive water resistant slurry explosives be used in many areas of the Main Zone pit. The dewatering system should also draw down the water table so blastholes will become dryer and less expensive ANFO can be utilized. The magnitude of shear strength on failure surfaces is required in order to evaluate stability of potential failures. Slip tests, point load tests and back analyses of existing failures were used to determine the shear strength parameters. Further studies should be carried out to better define the parameters at higher stress levels that will develop in a multi-berm failure. Further potential for pit steepening exists if the berm face in the volcanics can be maintained at a slightly steeper angle, e.g. 70 instead of the present 66°. It may be possible to achieve this goal if trim blasting procedures are modified to reduce blast damage to the final wall. / Applied Science, Faculty of / Mining Engineering, Keevil Institute of / Graduate

No description available.

No description available.

Sandsloot open pit mine extracts platinum, copper and nickel from the Platreef orebody in the Northern Limb of the Bushveld Complex. At present, it is the world's largest open pit platinum mine, but it is one of the smaller of six pits to be mined in this area by Potgietersrust Platinums Limited (PPRust). As mining progresses and the mine operations expand, sound knowledge of the subsurface ground, the orebody properties and their performance in the processing plant is imperative. An accurately characterised orebody, in terms of its geotechnical, geochemical and metallurgical properties, will facilitate the development of appropriate and cost effective mining practices and processing plant design. It will improve the prediction and performance of materials in each of the steps involved in converting the orebody rock mass into a concentrate /marketable product, which ultimately leads to mine-to-mill optimisation. This dissertation has focused on the geotechnical and metallurgical strength properties of the Platreef orebody at Sandsloot; the geochemical properties of the various lithologies and defined for each orebody rock type the associations and correlations within and between these properties. The petrography of the orebody material was studied to identify and classify the rock types. A rigorous testing programme was conducted and an extensive database of petrographic, geotechnical, geochemical and metallurgical information was assembled. The corresponding results within and across the different studies were grouped together and statistical analysis and interrogation of the data sets were performed. The research identified diverse rock types with contrasting physical properties in the Sandsloot open pit orebody. For each of the rock types the distinguishing characteristics and the variations in properties were identified. Significant differences and relationships between rock types for each property were assessed for predictability in mining. Statistical associations and correlations between the properties of each study were defined and models for predicting strength and rock type were developed. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2008.

Thesis (M.Phil.) - University of Queensland, 2006. / Includes bibliography.

This dissertation studies the evaluation of selectively mined, open pit gold deposits during the exploration stage of the mine's life. Since 1970 a large number of selectively mined, open pit gold mines have come into operation. The most common deposits include epithermal vein, mesothermal lode and laterite gold deposits. In general the deposits are characterized by small tonnages (1-20 million tonnes), relatively high grades (2-10 grams per tonne gold), submicroscopic to coarse gold, inexpensive mining, and both free milling and refractory ores.The key components that require evaluating during the exploration period are the deposit's geology, ore reserves, pit design, ore metallurgy and environmental impact. Feasibility studies are the main vehicle by which to report and guide the exploration programme. During the exploration period a company may undertake an initial (geological feasibility), second (preliminary mine feasibility) and third (final feasibility) delineation programme in order to gather sufficient data to justify a mine development decision. The responsibility of evaluating the mineral prospect lies primarily with the exploration geologist and mining engineer. Broad experience, a professional attitude, a thorough understanding of mining economics, and a high level of geological, engineering and technical skills are traits required by the evaluators. In order for mining companies to make sound investment decisions the geographical, geological, mining, metallurgical, environmental, marketing, political and financial aspects affecting the economic potential of the venture must be integrated so that the likely costs, risks and returns of the investment alternative are quantified. Ultimately, it is the economic analysis of these three items that determine whether the mineral prospect is developed into a mine I delineated further I retained until economic circumstances improve, or abandoned. To assess the costs, risks and returns, extensive use of the risk analysis is advocated throughout the exploration period . When combined with intelligent judgement of the intangible risk elements, the probabilistic distribution of discounted cash flows are invaluable in making sound investment decisions. However, the economic analysis is only as good as the information on which it is founded. Accurate and representative field data is the most important prerequisite to successfully evaluating and developing a new mine.

Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2003. / No abstract available

Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2001. / Over the last decade, as the mining industry of South Africa is moving to ever deeper mines, the borehole radar is becoming an increasingly important field of research. In December 2000, Burger completed his thesis on Electromagnetic Modelling of a Borehole Radar Environment with the FDTD Method. The goal of this thesis is to extend the research presented in Burger's thesis, considering how more advanced modelling techniques can be applied to the FDTD analysis of the borehole radar environment. Some of these techniques include implementation of dispersive and conductive material models, and developing Uniaxial Perfectly Matched Layer boundary conditions for matching these model. Simulations were run to measure the performance of these boundary condition for matching dispersive and conductive materials. The thesis also includes the implementation of a parallel version of the FDTD algorithm using the Message Passing Interface library. Finally several realistic borehole models where simulated to test the accuracy of the code and to show how the code can be used to model real world problems.

Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2000. / South Africa has an immensely rich reserve of minerals which still has to be exploited. The problem with these reserves is that they exist in reefs where the mining environment is extremely hazardous, and where mining is very expensive. These are only two of the reasons why borehole radar has recently become a very important field of research in the South African mining industry. These radars have to operate in rock, which has a number of electromagnetically problematic characteristics, which greatly complicate modelling and design of suitable radars. The goal of this project is to demonstrate how the Finite Difference Time Domain (FDTD) method may be used to electromagnetically model and simulate borehole radars and subterranean environments.

published_or_final_version / Applied Geosciences / Master / Master of Science