Search Documents

By S McKinley, S Juras, E Uludag

More and more, today’s mining geologists are asked to identify and create 3D value domains for multidisciplinary usage: grade definition, geometallurgical performance and geotechnical characteristics, to name a few. Often, that domain shape is the result of an assumed or conjectured value as a surrogate to a set of conditions (eg kaolinite-rich, sericite alteration). Would it not be instead better to create the respective domain through identification of a consistent quantifiable geologically-based pattern as its basis?Critical to the identification of patterns is the transformation of 3D point data into a model by a method that uses few, if any, preselected thresholds. Too often we complicate the reviews of the modelled data by prejudging the value range of interest. And when we do revert to 2D views (ie sections and plans), we tend to only examine numbers or line traces. These hinder and obscure identification of geological patterns particularly in deposits of complex geology. Instead, these data should be looked at with minimal prejudgment and interrogated in 2D space by one of the best and most eye-catching display types: filled contour plots.Here we present two different processes that transform data with minimal preselection into formats that allow for pattern recognition by filled contour plots. These are: probability assisted constrained kriging (PACK) and multiple interval interpolant formation (Aranz Geo’s Leapfrog® software). The former creates a 3D model of probabilities on a threshold value; the latter creates numerous (=10), regularly-binned 3D interval interpolants. The results of each method are examined as filled contours over numerous sections or plans. Any distinct patterns are quickly discerned thereby readily identifying the best value to base the creation of a domain. These processes therefore provide a way to marry recent advances in software tools with what is supposed a geologist’s core skill: pattern recognition.CITATION:Juras, S, McKinley, S and Uludag, E, 2017. Pattern recognition in transformed data – the search for domain shapes in mine geology data, in Proceedings Tenth International Mining Geology Conference 2017, pp 37–42 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By M Boon, M Franklin

This paper outlines the journey of cultural maturation and management system development at the Mt Rawdon (MRO) gold mine from its acquisition by Evolution Mining Limited (Evolution) in late 2011 to 2016.Evolution embarked upon a series of projects that aimed to improve the operational consistency and implementation of change on-site, while leveraging off the existing strengths of the operation. This document describes the gaps that were identified, the processes used to close them, and the resulting cultural change and production outcomes, with a specific focus on how to optimise the culture at any mining operation.MRO had a history of four owners in less than three years when it became a key asset of Evolution. The site leadership team (SLT) decided to influence the culture at MRO by reviewing and upgrading the existing management processes.The first priority was to improve transparency and collaboration at the SLT level, followed by improving competency in project management. The next phase was to strengthen the internal communication using a deliberately designed network of meetings, communication screens and other initiatives. Once there was some traction, the focus moved toward increasing production volume and decreasing cost per unit by improving short-term planning and execution capability. Together with other initiatives, this resulted in improved collaboration between all functions, which in turn netted over 37 per cent mining production uplift.Following solid success, a process of prioritisation and alignment management was implemented. This supported the ‘Mine to Mill one operation’ ideal and allowed the SLT to decide month-by-month what actions were to be prioritised. These priorities incorporated production realities and longer term imperatives of the balanced business plan.Much of this work was completed during a period of declining gold prices and a relentlessly strong Australian dollar, making it difficult to justify spending money on improvement projects. This work proved critical for the operation’s long-term survival.CITATION:Boon, M and Franklin, M, 2016. Improving consistency of delivery at Mt Rawdon Operation, in Proceedings International Mine Management Conference, pp 305-320 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 22, 2016

The Beginnings of Mineral Processing Research in Canada - A Short Account

Sep 13, 2010

Certain Molybdenum Resources in Indonesia Mineralogical and Processing Study

Sep 13, 2010

Consents Required for Overseas Persons Overseas Investment Regulations 1974 Foreign investment proposals must be reviewed by the Overseas Investment Commission to ensure that these are in accord with national interests. Consent must be obtained from the Commission for: 1. New investment proposals which include: a. An overseas person acquiring 25 per cent or more of any class of share in a company. b. A New Zealand company issuing shares to an overseas person where this will result in that person owning 25 per cent or more of the company. c. An overseas person acquiring business assets for consideration in excess of $100 000. d. An overseas person commencing business in New Zealand. 2. Borrowing in New Zealand: An overseas person must obtain consent to raise funds in excess of $300 000 in New Zealand. 3. Borrowing Overseas: New Zealand incorporated companies must obtain consent to borrow overseas. Current policy is borrowing will be approved where the loan is for a specified fixed term of one year or more.

Jan 1, 1982

By K Guilfoyle

AngloGold Ashanti Australia Ltd operates an underground mine below a large open pit at the Sunrise Dam Gold Mine near Laverton in Western Australia. Operations are based on an extensive mineralised zone which has very complex geometry, has a high ‘nugget effect’, and is difficult to interpret and model. Initial underground ore was produced from relatively narrow orebodies dipping from 15º - 70º. Open stopes aimed to selectively extract high-grade ore, using methods including jumbo stripping and longhole drilling and blasting. The complex geology makes it difficult to accurately locate development and stopes in the positions required for profitable production. In narrow stopes, rock mass damage and overbreak dilute ore grades and increase the cost per ounce of gold poured. In flat orebodies, several different techniques have been used to recover blasted ore but overall productivity is low. Thus selective mining can also be slow, costly and recovers only a portion of the available mineral resources. Large longhole open stopes with cemented paste backfill are used to extract multiple zones of mineralisation from the Cosmo and GQ orebodies. Bulk emulsion explosives and electronic detonators are used in all large stope blasts to reduce the risk of misfires and to accurately control blasthole initiation sequences and delay timing. Larger stopes improve productivity and significantly reduce direct mining costs, enabling the use of lower economic cut-off grades which increase the overall recovery of mineral resources. This paper reviews the evolution of open stoping at Sunrise Dam, the various mining methods and drilling and blasting practices used, the results achieved, and the lessons learned.

Nov 8, 2011

By R L. Grogan

Mining is currently undergoing a progressive expansion into novel environments (such as the deep ocean), commodities (such as tantalum, rare earths, and other ‘green economy minerals’), and new methods (such as the autonomous underwater cutting machines required to operate in the deep ocean environment, or the use of expanding grouts to deliver a blast-free mining method). The advent of novel mining, environments and commodities heralds an era that will undoubtedly start with much discomfort on the part of regulators and stakeholders, due to a feeling of overwhelming uncertainty. These proposed mining scenarios have few precedents, few examples of successful implementation, short baseline monitoring periods, and few examples of legacy sites that may assist with understanding long term risk and exposure. The evolution of the environmental and social impact assessment (ESIA) process in many regulatory environments recognises stakeholder engagement in a formal and facilitated manner. This is a positive step, and allows stakeholders to be much more meaningfully involved in the permitting process than they historically were. However, with this advance comes the challenge of identifying and communicating with stakeholders; sharing information in a meaningful way, fostering relationships with what can be an extremely large group, and delivering on commitments that inspire confidence to permit operations that have never been permitted before. In order to meet this challenge, it is suggested that changes to collection of data, communication of data, the nature of commitments, and the reporting of performance need to be made in order to effectively communicate management of new technologies, and the impacts that mining may have in new environments (such as the deep ocean). The communication challenge is necessarily greater when describing technology that has never been used, or environments that have never previously been accessed by humans on an industrial scale. CITATION:Grogan, R L, 2018. Permitting in the face of uncertainty – how to deliver confidence to regulators and investors, in Proceedings Life-of-Mine 2018, pp 46–48 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 25, 2018

By R Munoz, R González, J Vallejos, A Delonca

In panel caving in underground mines, it is essential to characterise and monitor the stress and stability state of production level pillars to ensure the extraction of the mineralised ore column and the safety of workers. Pilar Norte is a sector in the El Teniente mine that forms a pillar between the undercut fronts of the adjacent Esmeralda and Reservas Norte sectors. It exists in a high-stress environment, which may induce damage to the rock mass production pillars. Generally, numerical models are calibrated using observed damage in galleries. This procedure does not discriminate between the structural condition and/or the blasting damage effects. This paper proposes a technique that uses borehole cameras to measure stress-induced damage. This has the advantage of being at the intact rock scale, meaning that the effect of geological structures is negligible and the blasting damage factor is eliminated. Comprehensive geotechnical characterisation and tomography monitoring has been undertaken at Pilar Norte to describe and determine the rock mass behaviour of the production pillars. By combining analytical, empirical and numerical models, a correlation between the measured overbreak recorded by the borehole cameras and the stress level of the pillar was developed. The methodology can be routinely applied to estimate the stress state in the production pillars.CITATION:González, R, Munoz, R, Vallejos, J and Delonca, A, 2016. Characterisation and monitoring of the stress state of production pillars at El Teniente Mine, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 197–202 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By L Bartsch, M Kelahan, E Wingate, J-S David

The use of column flotation cells for recovery of phosphate is becoming more common practice in certain parts of the world (Brazil, Russia) where igneous phosphate ores are processed. Igneous phosphates are generally finer grained (< 200µm) than some of the traditional sedimentary phosphates (<400µm). Australian phosphate from the Georgina basin is sedimentary, but has a much finer grain size (typically < 106µm) than similar deposits in North Africa and the USA.In 2013, Arianne Phosphate completed a bankable feasibility study for the development of their igneous phosphate deposit at the Lac a Paul site in Quebec. Initially, lab test work and bench scale piloting indicated that using traditional mechanical flotation would be able to produce adequate concentrate grade and an economic level of recovery, but would necessitate the installation of a complex and operationally challenging flotation circuit. Later pilot plant testing using column cells resulted in a significant reduction in process complexity and facilitated the processing of the -20µm ore fraction which resulted in a 10% increase in P2O5 recovery and a 5% increase in concentrate grade %P2O5.Flotation column testing achieved a concentrate grade of 38.6% P2O5 at a P2O5 recovery of 90%. Using a mechanical flotation cell circuit, the concentrate grade was 36.4% P2O5 with a P2O5 recovery of only 78.8%. A noticeable feature of the testing was the simplicity of the column flotation circuit configuration (Rougher + 2 stages of cleaning + Cleaner Scavenger) compared to the mechanical flotation cell circuit (Rougher + Scavenger + 3 stages of cleaning).The financial benefit for this case study was estimated using a sales price of US$ 195/t FOB for a 38.6% P2O5 product, and an assumed cost of production of US$ 95/t, the netback price is calculated at US$100/t. For a daily milling rate of 55,000t/d, the improved flotation performance provides additional concentrate production of 1,203t/d. Using the netback price calculated above, this calculates to additional gross profit of US$ 120,260/d.Annualised, this equals US$ 40.7 million in additional revenue for a similar or reduced CAPEX.The use of column flotation on fine grained phosphate ore types often requires fine grinding and desliming to liberate the phosphate value, such as the Australian sedimentary phosphate ores. This may enable the development of deposits previously regarded as uneconomic.This paper discusses the potential benefits available to operators, and developers of new projects, for the use of column flotation cells in their metallurgical circuits as assessed by an engineering company.CITATION:Wingate, E, Kelahan, M, David, J-S and Bartsch, L, 2015. Does it make cent$ to use flotation columns for phosphate beneficiation?, in Proceedings MetPlant 2015, pp 353–365 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

The Effect of Mineral Liberation on the Floatabilities of Pyrite, Arsenopyrite and Arsenian Pyrite for Carlin Trend Ores

Sep 13, 2010

By Baker G

The exposures resulting from development work, following on the discovery of a new shoot of hIgh grade ore at the north end of the Sardine tin mine, during 1952, have provided an unusual opportunity to study the oxidation of a stannite-rich ore. Through the kindness of C. C. Morton, Chief Government Geologist of Queensland, an exactly located suite of specimens representative of the exposures was supplied by J. and W. Reddie. This was later supplemented by a number of specimens culled from a parcel ofrepresentative ore submitted to the Melbourne Ore Dressing Laboratory for testing.The Sardine tin mine, near Ewan, Queensland, has been the outstanding producer of the Kangaroo Hills Mineral Field. Since its discovery in 1918, up to 1952 it has yielded about 1,500 tons of cassiterite concentrates, and about 85 tons of stannite concentrates. The outcrop ore averaged 35% tin oxide, but the grade declined with increasing depth, and by 1930 had fallen to 7% tin oxide. In the northern section of the mine the ore shoots show a downward passage to complex primary s.ulphide ore, containing cassiterite and abundant stannite.The orebodies occur in a series of fissures in a crushed zone about 50 ft. wide in slates and quartzites that have been intruded by granite (Connah, 1952). A quartz porphyry dyke forms the footwall of the original main lode in its southern part, being traced' from the surface to' the No. 4 level (173 ft. vertical depth), and two narrow dolerite dykes were encountered in the workings north of the main...

Jan 1, 1954

The issue of retrenchment is a topic of considerable relevance for the Papua New Guinea (PNG) mining, petroleum and gas industries. The unique environments in which Porgera Joint Venture (PJV) and other similar operations operate are likely to confront these industries with particular dilemmas that will require a range of investments to mitigate the problems associated with retrenchment and employment. This paper discusses retrenchment and employment in the PNG mining industry using the specific case study of PJV. The paper deals with the issue of employment and retrenchment of local workforces in the PNG context, which presents a serious challenge for the resources industry and the achievement of sustainable development objectives. The issue of future retrenchment of the workforce as a result of mine closure is an obvious challenge for both PJV and the Porgeran community at large, who have now come to rely upon both the employment opportunities presented through the mining. This paper examines these challenges and in doing so highlights some progress made by PJV. The paper also discusses downsizing, strategic practices and holistic approaches of retrenchment and employment. In doing so the paper highlights issues that have been overlooked in both academic and applied studies from global and local perspectives in the PNG mining sector. The latter sections articulate the relevance of the information provided by the case study in the wider context of retrenchment. The conclusion promotes a perspective that a great deal more investment will be required by all stakeholders to respond to the challenges of managing retrenchments and mine closure.

Jan 1, 2009

By E Apaza, R Neumayr

This paper aims to summarise the discovery of the QTS Central resource, a previously unidentified +1 Mt inferred resource that lies between two major CSA resource systems.The 1.7 Mt at 5.76 per cent Cu, QTS Central ore system represents 1/6th of the CSA mineral resource and was discovered in 2014 based on the accumulation of historic exploration records dating back to 1989.The CSA deposit consists of five ore systems hosted within turbidite-derived siltstones (CSA Siltstone) and lesser sandstones (five per cent) of the Devonian Amphitheatre Group. The host sediments strike approximately north–south with a steep westerly dip and exhibit a well-developed east dipping cleavage. Most CSA mineralisation is hosted within dilation zones at the intersection of cross-cutting structures and is interpreted as epigenetic in origin.Alteration and weak mineralisation, up plunge to the reported QTS Central mineral resource, was initially detected in 1990 during a downhole electromagnetic conductivity (EM) study, where one hole indicated an off-hole conductor, later tested with four diamond holes. One of these diamond holes intersected 3 m at 7.5 per cent Cu at 200 m. Development of the 9070 Subway drive in 2005/2006, linked the QTS North and QTS South workings and intersected structures interpreted to host QTS Central mineralisation. Subsequent drilling proximal to the 9070 Subway in 2007 identified an up plunge extension to the QTS Central zone (UDD07152: 1.8 m at 6.3 per cent Cu from 10.7 m). Work on QTS Central was largely forgotten until 2012 when the mining of a 450 m infrastructure drive provided a platform to test the anomalous grades. In December 2013, drill hole UDD13055A intersected 20.9 m at 7.2 per cent Cu from 378 m. By the end of 2014, the QTS Central inferred resource was 1.0 Mt at 6 per cent Cu and 18 g/t Ag (Hosken and Apaza, 2014). Late in 2016, further infill drilling occurred from two fronts to increase confidence in the QTS Central resource. The results of this drilling are expected late in 2017.The current interpretation indicates the QTS Central system consists of two main lenses hosted within closely bedded sandstones and siltstones. The sandstone in general is not mineralised, being heavily silicified, while the siltstone is mineralised and chloritised. The main mineralised lens is 75–200 m along strike and 450 m high. Massive sulfide feeder structures lie at the core of the two main lenses, although the characteristics of the QTS Central system tend toward the mineralisation being more chlorite-rich than in QTS North and QTS South.CITATION:Apaza, E and Neumayr, R, 2017. The discovery of the QTS Central ore system, CSA mine, Cobar, NSW, Australia, in Proceedings Tenth International Mining Geology Conference 2017, pp 151–156 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

The New South Wales coal industry is a highly mechanised well organised industry which has developed from an annual production of slightly less than 13 million tons in 1950 to over 33 million tons in 1969. Although continuous miners were not introduced into the mines until 1950, by Jillle 1969 the percentage of coal won by these units was 87.3. The paper describes mining conditions in the various coalfields of the State, their complexities and problems and how these have been dealt with. The introduction of fully mechanised long wall faces has presented a challenge which has been accepted and descriptions of systems in use are discussed. Major expansion of the industry is anticipated to meet the requirements of the growing Australian steel industry, for local power generation and to meet the increasing demands of overseas markets.

Jan 1, 1971

The theme of this Conference is 'The Future of Mining in New Zealand' to be addressed at a time of deepening economic concern. To ensure the assessment and development of our mineral resources in a competitive, safe and environmentally acceptable way a modest supply of a rare commodity û the professional mining engineer û must be assured. This paper briefly' reviews the history of mining education in New Zealand, discusses relevant overseas academic concerns and actions and discusses recent local trends which have led to a most serious recruitment position in the Department of Mining Engineering at the University of Auckland. Conclusions are drawn and proposals made which may remedy this situation which could have serious economic and sociological consequences for New Zealand.

Jan 1, 1991

By Rogerson R, Queen L

The petrology and age of mid Cretaceous to Palaeogene marine volcanics may provide important clues to the palaeogeography of the period, particularly for tectonic elements and events outboard of the Papuan Basin. This initial survey of known marine volcanics of this age reveals a paucity of reliable data on isotopic ages, geochemistry and syngenetic mineralisation on virtually all units. Existing data allows a tentative subdivision of known marine volcanics into either MORB-like early Palaeogene rifts/ marginal basins, early Palaeogene ensimatic arc rocks overlying ?Late Cretaceous and Palaeogene fore-arc/marginal basin crust, late Palaeogene ensimatic arc rocks, and mid to Late Cretaceous ensialic rift rocks. Due to lack of data, some units are difficult to classify into these categories.

Jan 1, 1991

By A J. Weston

Block or panel caving technology is far removed from that of the top slicing and block caving of the late nineteenth or early twentieth centuries. The rapid mechanisation and expansion of these methods in the late twentieth century was as much a result of the change of the technology of the unit operations of development, ground support, drilling and blasting and transport as it was of the advances in geotechnical understanding and practice. The small footprint gravity and scraper block caving mines with boundary weakening, rail transport and shaft hoisting of the early to mid-twentieth century have been replaced by massive high lift panel caves using preconditioning of the ore, large load-haul-dump units, adjacent crushers and conveyors to surface. The technology changes in the unit operations are described and the drivers for these changes examined.CITATION:Weston, A J, 2016. The evolution of block caving technology, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 265–274 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

During the last 125 years, the steel industry has witnessed revolutionary changes in the process of steelmaking. The Bessemer process was the predominant steel production technology during the last two decades of the 19th century. The open hearth process accounted for the lion's share of world steel production for six decades from 1910 to 1970. With the appearance of the LD process on the industrial stage in 1952, the importance of open hearth process declined and currently the basic oxygen processes are contributing more than 60 per cent of the world steel production. The LD process also led to the development of several other oxygen blown processes such as LDAC, OLP, OBM, QBOP, EOF, Clc.

Jan 1, 1999

Energy Dissipation in Long-Distance Slurry Pipelines

Sep 13, 2010

By G Marling, A Calderon, J Harris, P Kirsch, M Shi, D Sprott, A Kirsch

Large-scale infrastructure construction needs to comprehensively manage risks that can impact the health and well-being of many people, from workers (temporary, contracted or full time), to families and surrounding communities. This paper starts with an analysis of incidents (injury, fatality, other damage) in tunnel construction between 2000 and 2014 and assesses the distribution of these events by continent, year, and severity of outcomes. These incidents are then analysed and mapped to a framework of hazards derived from RISKGATE (2014). A comparative register of current tunnel construction risk management guidance is derived from current Australian codes of practice and this register is also mapped to the RISKGATE framework of hazards to identify where coal industry knowledge may offer utility to the tunnelling industry.An initiative of the Australian Coal Association Research Program (ACARP), RISKGATE is an interactive online risk management system developed to assist the mining industry in implementing continual improvement in the management of major unwanted events. To date, a comprehensive knowledge base has been captured for risk management of tyres, collisions, fires, isolation, strata underground, ground control open cut, explosions, explosives, outbursts, coal bumps and bursts, human/machine interface, manual tasks, slips/trips/falls, inrush and occupational hygiene. By capturing operational knowledge from industry experts, RISKGATE provides a cumulative corporate memory at a time of high personnel turnover in the coal industry.This paper proposes and outlines how knowledge within the RISKGATE platform could be applied to managing the significant health and safety risks associated with tunnelling. The authors suggest that to varying degrees the knowledge already captured in RISKGATE is likely to be transferable to tunnelling construction operations. Please note that this paper focuses on tunnel construction and does not address risk management of tunnels in operation (eg road transportation or utility networks).CITATION:Kirsch, P, Kirsch, A, Calderon, A, Marling, G, Harris, J, Shi, M and Sprott, D, 2014. Management of health and safety in tunnelling – application of Australian coal mining knowledge, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 563–572 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014