This paper presents a new risk assessment methodology for coal mine excavated slopes. This new empirical-statistical slope.stability assessment m. ethodology （SSAM! is intended for use by geotechnical engineers at bo...This paper presents a new risk assessment methodology for coal mine excavated slopes. This new empirical-statistical slope.stability assessment m. ethodology （SSAM! is intended for use by geotechnical engineers at both the design review and operational stages of a mine＇s life to categonse the risk of an excavated coal mine slope. A likelihood of failure is determined using a new slope stability classification system for excavated coal mine slopes developed using a database of 119 intact and failed case studies sourced from open cut coal mines in Australia. Consequence of failure is based on slope height and stand-off distance at the toe of the excavated slope. Results are presented in a new risk matrix, with slope risk being divided into low, medium and high categories. The SSAM is put forward as a new risk assess- ment methodology to assess the potential for, and consequence of, excavated coal mine slope failure. Unlike existing classification systems, assumptions about the likely failure mode or mechanism are not required. Instead, the SSAM applies an approach which compares the conditions present within the exca- vated slope face, with the known past performance of slopes with similar geotechnical and geometrical conditions, to estimate the slope＇s propensity for failure. The SSAM is novel in that it considers the depo- sitional history of strata in an excavated slope and how this sequence affects slope stability. It is further novel in that it does not require explicit measurements of intact rock, rock mass and/or defect strength to rapidly calculate a slope＇s likelihood of failure and overall risk. Ratings can be determined entirely from visual observations of the excavated slope face. The new SSAM is designed to be used in conjunction with existing slope stability assessment tools.展开更多
Computerized geological models are the basis of modern mine design,planning and production.A sound,validated geological model is essential to the success of a min- ing project.However,due to the complexity of geology ...Computerized geological models are the basis of modern mine design,planning and production.A sound,validated geological model is essential to the success of a min- ing project.However,due to the complexity of geology surrounding deposits,geological models inherit uncertainty,or error.This geological uncertainty may significantly affect the risk profile of a mining project during its design and operational phases.Methodologies for quantifying geological uncertainty and risk have been developed by CRC Mining and the University of Queensland,Australia and successfully applied to case studies.This paper discussed the implications of geological uncertainty and risk to a coal mining project,and presents advances for quantifying geological/geotechnical uncertainty and risk.A case study is presented to demonstrate the application of the technology developed.展开更多
The cratonisation of Western Australia during the Proterozoic overlapped with several key events in the evolution of Earth. These include global oxidation events and glaciations, as well as the assembly,accretionary g...The cratonisation of Western Australia during the Proterozoic overlapped with several key events in the evolution of Earth. These include global oxidation events and glaciations, as well as the assembly,accretionary growth, and breakup of the supercontinents Columbia and Rodinia, culminating in the assembly of Gondwana. Globally, Proterozoic mineral systems evolved in response to the coupled evolution of the atmosphere, hydrosphere, biosphere and lithosphere. Consequently, mineral deposits form preferentially in certain times, but they also require a favourable tectonic setting. For Western Australia a distinct plate-margin mineralisation trend is associated with Columbia, whereas an intraplate mineralisation trend is associated with Rodinia and Gondwana, each with associated deposit types. We compare the current Proterozoic record of ore deposits in Western Australia to the estimated likelihood of oredeposit formation. Overall likelihood is estimated with a simple matrix-based approach that considers two components: The "global secular likelihood" and the "tectonic setting likelihood". This comparative study shows that at least for the studied ore-deposit types, deposits within Western Australia developed at times, and in tectonic settings compatible with global databases. Nevertheless, several deposit types are either absent or poorly-represented relative to the overall likelihood models. Insufficient exploration may partly explain this, but a genuine lack of deposits is also suggested for some deposit types. This may relate either to systemic inadequacies that inhibited ore-deposit formation, or to poor preservation. The systematic understanding on the record of Western Australia helps to understand mineralisation processes within Western Australia and its past connections in Columbia, Rodinia and Gondwana and aids to identify regions of high exploration potential.展开更多
基金funded by the Australian Coal Association Research Program(ACARP)
文摘This paper presents a new risk assessment methodology for coal mine excavated slopes. This new empirical-statistical slope.stability assessment m. ethodology （SSAM! is intended for use by geotechnical engineers at both the design review and operational stages of a mine＇s life to categonse the risk of an excavated coal mine slope. A likelihood of failure is determined using a new slope stability classification system for excavated coal mine slopes developed using a database of 119 intact and failed case studies sourced from open cut coal mines in Australia. Consequence of failure is based on slope height and stand-off distance at the toe of the excavated slope. Results are presented in a new risk matrix, with slope risk being divided into low, medium and high categories. The SSAM is put forward as a new risk assess- ment methodology to assess the potential for, and consequence of, excavated coal mine slope failure. Unlike existing classification systems, assumptions about the likely failure mode or mechanism are not required. Instead, the SSAM applies an approach which compares the conditions present within the exca- vated slope face, with the known past performance of slopes with similar geotechnical and geometrical conditions, to estimate the slope＇s propensity for failure. The SSAM is novel in that it considers the depo- sitional history of strata in an excavated slope and how this sequence affects slope stability. It is further novel in that it does not require explicit measurements of intact rock, rock mass and/or defect strength to rapidly calculate a slope＇s likelihood of failure and overall risk. Ratings can be determined entirely from visual observations of the excavated slope face. The new SSAM is designed to be used in conjunction with existing slope stability assessment tools.
文摘Computerized geological models are the basis of modern mine design,planning and production.A sound,validated geological model is essential to the success of a min- ing project.However,due to the complexity of geology surrounding deposits,geological models inherit uncertainty,or error.This geological uncertainty may significantly affect the risk profile of a mining project during its design and operational phases.Methodologies for quantifying geological uncertainty and risk have been developed by CRC Mining and the University of Queensland,Australia and successfully applied to case studies.This paper discussed the implications of geological uncertainty and risk to a coal mining project,and presents advances for quantifying geological/geotechnical uncertainty and risk.A case study is presented to demonstrate the application of the technology developed.
基金supported by the Exploration Incentive Scheme,administered by the Geological Survey of Western Australia as part of the Royalties for Regions programme of the Western Australian state government
文摘The cratonisation of Western Australia during the Proterozoic overlapped with several key events in the evolution of Earth. These include global oxidation events and glaciations, as well as the assembly,accretionary growth, and breakup of the supercontinents Columbia and Rodinia, culminating in the assembly of Gondwana. Globally, Proterozoic mineral systems evolved in response to the coupled evolution of the atmosphere, hydrosphere, biosphere and lithosphere. Consequently, mineral deposits form preferentially in certain times, but they also require a favourable tectonic setting. For Western Australia a distinct plate-margin mineralisation trend is associated with Columbia, whereas an intraplate mineralisation trend is associated with Rodinia and Gondwana, each with associated deposit types. We compare the current Proterozoic record of ore deposits in Western Australia to the estimated likelihood of oredeposit formation. Overall likelihood is estimated with a simple matrix-based approach that considers two components: The "global secular likelihood" and the "tectonic setting likelihood". This comparative study shows that at least for the studied ore-deposit types, deposits within Western Australia developed at times, and in tectonic settings compatible with global databases. Nevertheless, several deposit types are either absent or poorly-represented relative to the overall likelihood models. Insufficient exploration may partly explain this, but a genuine lack of deposits is also suggested for some deposit types. This may relate either to systemic inadequacies that inhibited ore-deposit formation, or to poor preservation. The systematic understanding on the record of Western Australia helps to understand mineralisation processes within Western Australia and its past connections in Columbia, Rodinia and Gondwana and aids to identify regions of high exploration potential.
