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By Y T. J Kwong

With the recent emphasis worldwide on environmental protection and sustainable development, finding an enriched mineral deposit no longer guarantees mining development. Only if the identified resource can be exploited in an environmentally-friendly manner is it possible that a mine may be developed. Designed primarily to aid with exploring for similar deposits of a particular type, traditional genetic ore deposit models tend to ignore the fact that all mineral deposits are characterised by type-specific environmental signatures. In fact, how an ore deposit can be mined, the commodities of interest extracted and the resultant mine wastes managed are all largely dictated by the geology and mineralogy as well as the environmental setting of the deposit. An environmental ore deposit model integrates such related information to identify the environmental challenges associated with mining an ore deposit of a particular type and facilitates the selection a suitable combination of methods to minimise environmental risks and impacts. Given that environmental management consumes a large portion of the budget for a modern mining project, making informed decisions at all stages of mining development can reduce the overall project cost. Through case examples, this paper demonstrates how environmental ore deposit models may be useful in mine permitting, active mining and in site decommissioning. It is only through an innovative and flexible approach that the mining industry can shed its tarnished image and gain the social license to mine.

Aug 22, 2011

By J E. Powalisz

Obtaining a representative sample of bulk materials in process industries is critical to providing valid data for process control and custody transfer (valuation). The accuracy of a sample, that is to say how well the sample represents the material in the process, is directly related to how well the process can be controlled and to how much a product may be worth. Sampling accuracy then is in fact related to bottom line profitability.Sampling theory offers information and equations on how to take a representative sample from a process, however, the actual practice of extracting a sample from the process can be more of an art.Key sampling variables include product specifications such as bulk density, particle distribution, material conveyance, practical sampler location, sampler type and sample frequency and volume/mass.This paper discusses basic sampling theory, sampling methods, types of samplers, how to develop a ‘real world’ sampling system and current manual and automated samplers.Key points include ‘practical precision and variance’, material properties, flow properties, direct sampling versus indirect sampling, sampler types and applications.CITATION:Powalisz, J E, 2014. Bulk solids sampling, in Proceedings Sampling 2014 , pp 179–188 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 29, 2014

By R Ballantyne, M Adams

Time Usage Models, used as a basis for calculating performance indicators for mobile mining equipment, have developed from very simple to very sophisticated models. This development has paralleled the increased collection and analysis of production data that itself has been enabled by the evolution of underground voice and data communications along with the relevant information systems. A Time Usage Model divides the hours that equipment is (or is not) used into standard components, by a hierarchical breakdown, so that measures of productivity can be used to compare performance of both people and equipment. The calculation of equipment availability, and thus the underlying Time Usage Model, has always been an extremely emotive topic as different groups use time usage information for different purposes. The direct link between measuring performance Key Performance Indicators (KPI) calculated from these models and employee rewards impacts upon the workforce. This paper discusses the conflict in use by various stakeholders and proposes ways to address some of the more contentious issues each supported by case studies. The simple status code functionality used by early systems has proven inadequate, leading to the evolution of “work-arounds”. These workarounds have become the norm and unfortunately have become embedded in the next generation of models and the information systems that incorporate them. This paper contends that the industry should stop building Time Usage Models to accommodate shortcomings in proprietary systems, but rather collaborate with suppliers to develop innovative methods to deal with the fundamental requirements. There are many points of differentiation that are not clear-cut. Pitfalls are discussed as well as threats to success. A framework of rules is developed as guidelines for how a Time Usage Model should be developed and applied. This will hopefully stimulate the on-going discussion as to how Equipment Availability and other components of the model should be calculated.

Mar 15, 2021

By S Farrokhpay, C Akop

Copper-gold-pyrite ore types with an elevated pyrite head grade utilise a sequential flotation circuit to recover initially a copper-gold concentrate with a pyrite-gold concentrate being produced from the tailing of the initial circuit.A simpler flotation circuit with lower operating and capital costs for treatment of such copper-gold-pyrite ores with an elevated pyrite head assay was sought in the described work. After characterising the ore, the objective was to apply bulk rougher flotation of both the copper minerals and pyrite for the copper-gold-pyrite ore at natural pH. Hence, no lime or other pyrite depressants were required in bulk roughing. The bulk rougher concentrate was upgraded in a cleaner circuit to reject non-sulfide gangue and then the resulting sulfide concentrate was separated by depressing the pyrite to produce two products (copper and pyrite concentrates, both having significant gold assays). A standard test with a sequential circuit was applied to the same ore for comparison.The chalcopyrite and pyrite losses in the tailing from the rougher circuit were the same for both bulk and sequential roughing (less than six per cent). In cleaning (bulk circuit), the effective pH for pyrite depression was 11.8–11.9; copper recovery was 70–75 per cent (grade of 15–20 per cent copper) and the sulfur recovery (pyrite product) was 80–85 per cent (grade of 34–36 per cent sulfur).These results approached those for the sequential circuit where copper recovery was 80–85 per cent (grade of 15–20 per cent copper) and the sulfur recovery (pyrite product) was 83 per cent (grade of 38 per cent sulfur).The observed effects of feed sizing on the liberation of minerals in the rougher feed are discussed. Options for improving the bulk circuit results are also considered. Importantly, the implications of various aspects of these findings for the bulk circuit are discussed with an industrial focus.CITATION:Akop, C, Farrokhpay, S and Johnson, N W, 2014. An alternative circuit for chalcopyrite-pyrite ores with elevated pyrite content in Cu-Au ore treatment, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 407–416 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

By S Whitton, W Wimmler, L Wimmler

“Given the increasing scrutiny of the mining industry and its relatively poor record with regards to mine tailings management, increased requirements to minimise water usage (often accompanied by very high costs of water) and the need to demonstrate achievable long-term closure strategies, it is likely that the option of a filtered tailings system will need to be considered in many operations in future.” (Australian Centre for Geomechanics, 2018). Given such a statement as a conference introduction, it is only appropriate that a range of potential technologies are investigated and compared, to create awareness for even underrated but appropriate technologies. The advantages and disadvantages of all technologies need to be considered and analysed. Suppliers are swift to promote their technologies advantages; however aspects of sustainability are not always fully understood. Perhaps a combination of two filtration technologies is appropriate. This paper delves into the technical details, good or bad, of four mechanical dewatering technologies in tailings dewatering and provides insight on an undervalued and, in the author’s opinion, young technology – the screw press.

Jul 1, 2021

By D Stow, R Goodridge, K J. Molloy

A range of explosives has been specifically developed for soft ground blasting. These explosives can be used in both wet and dry blasting conditions, range in density from 0.3 - 1.2 g/cc and range in VoD from 2 - 4.5 km/s. This range of explosives has the potential to be tailored to ground type and is predicted to be suitable for a variety of applications which include: blasting in soft to medium overburden, coal blasting, wall control, and low vibration blasting. Trials have been conducted in several applications with encouraging results. Several cast/throw blasts have been conducted with these products partially replacing either ANFO or Heavy ANFO. The results from the blast have been equivalent in cast (per cent) and at reduced cost per unit volume. These products have also been used in presplit blasting and have again achieved equivalent or better results when compared to conventional presplit blasting at a lower cost per unit volume. This product has also been used in a vibration sensitive area replacing traditional explosive products, and generating excellent fragmentation and digging whilst maintaining vibration limits. This new range of products, NOVALITE, has shown great potential in many applications either reducing cost per unit volume, improving wall quality or improving productivity in environmentally sensitive areas.

Jan 1, 2001

By D Alexander

For nearly 100 years, the flotation plant metallurgist has often wondered what is happening æbeneath the frothÆ. To assist in unravelling this mystery, new technology has been developed as part of the Australian Mineral Industries Research Association (AMIRA) P9 project, to measure gas dispersion characteristics (such as gas hold-up, superficial gas velocity and bubble size) in industrial flotation cells. These measurements have been conducted in a large number of cells of different types and sizes by researchers from the Julius Kruttschnitt Mineral Research Centre (JKMRC) and JKTech. A large database has been developed and the contents of this database are described in this paper. Typical cell characterisation measurements show a wide spread in values, even in the same cell types and sizes performing similar duties. In conventional flotation cells, the typical gas hold-up values range from 3 - 20 per cent, bubble sizes range between 1 and 2 mm, and superficial gas velocity ranges from 1 to 2.5 cm/s. The ranges of cell characterisation measurements given in this paper will enable plant personnel to compare their operation to other similar types of operations from around Australia and the rest of the world, giving opportunities for further improvement to flotation plant operations.

Jan 1, 2005

By J Ireland, S Rose

The main outcomes of mining grade control include defining the boundary between ore and waste and then categorising the ore according to which stockpile it should be sent. A typical workflow includes using general mine planning software (GMP) – such as SurpacTM, VulcanTM or CAE StudioTM – to create three-dimensional wireframes of mineralisation domains, which are used to flag the relevant samples of interest and constrain estimation during block modelling. Creating the wireframes is a time-consuming process, requiring reasonable software skills, patience and an eye for detail. The interpretations can be subjective; indeed, even the same geologist will give different shapes if presented with the same data at different times. The process can become particularly tedious when trying to carry out updates due to new data. It can also be difficult to test the effect of alternative interpretations or grade thresholds because of the time constraints in production.There are now several implicit modelling tools available, either as standalone programs or as add-on modules to existing GMP. In this paper, the authors develop a workflow using implicit modelling methods to show how grades and geology can be rapidly interpreted to provide effective domains for grade estimation. The paper includes case studies from open pit gold mines. The implicit modelling approach can save several days of interpretation work for each grade control drilling campaign.CITATION:Rose, S and Ireland, J, 2014. Implicit modelling applied to grade control data, in Proceedings Ninth International Mining Geology Conference 2014 , pp 115–122 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014

Adsorption isotherms, zeta potential and coagulation techniques have been used to exa- mine the mechanism of metal activation on SiO2 and ZnS surfaces. The importance of surface nucleation or precipitation of metal hydroxide coatings is'established and identified-by characteristic charge reversal patterns. The significance of surface coatings in sulphide and non-sulphide flotation is discussed.

Jan 1, 1973

By H Sichani-Teimouri, B N. Noller, J C. Ng, R N. Alsaadi, P L. Breuer, S Shini

Cyanide has been used for over a century worldwide for gold extraction. However, the presence of several metals and metalloids in ore requires greater amount of cyanide for an efficient gold recovery due to their solubilisation in conjunction with gold. The extraction residues are discharged into tailing storage facilities (TSFs) and may cause bird mortality if there is exposure to cyanide-bearing wastewater exceeding the toxic threshold. The toxicity arises from free cyanide released from weak acid dissociable (WAD) cyanide complexes. The International Cyanide Management Code (ICMC) has deemed 50 mg/L of WAD cyanide released into TSFs to be safe for wildlife protection. However, this concentration is based on observations of an apparent lack of toxicity rather than a toxicological approach. The National Industrial Chemicals Notification and Assessment Scheme (NICNAS) identified in 2010 that there is a lack of toxicity data to properly assess the environmental significance of cyanide levels at gold mines. Lack of knowledge for the toxicity of free cyanide and metal cyanide complexes to wildlife led to consider alternative direct assessment techniques for designating safe levels. Whilst toxicity may be assessed by using young chickens with animal ethics approval, the traditional bioassay approach to assess cyanide toxicity is impractical for gold mine TSFs. Bioassays using algal species such as Euglena gracilis, a unicellular alga, are widely used for ecotoxicological studies. A unique feature is that the Euglena gracilis Z cell has plant-like while SMZ cell has animal-like characteristics. The aims of this project are to evaluate the suitability of Euglena gracilis Z and SMZ strains to assess the toxicity of free cyanide and both strong (cobalt) and weak (zinc, copper and nickel) acid dissociable metal-cyanide complexes that may be present in TSFs.CITATION:Noller, B N, Ng, J C, Shini, S, Breuer, P L, Sichani-Teimouri, H and Alsaadi, R N, 2014. Development of a toxicity approach to evaluate free cyanide and metal cyanide complexes in waters associated with gold and other mining, in Proceedings Life-of-Mine 2014 , pp 573–590 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By S Tierney, D Cumming-Potvin, I Thin, Y Potvin, D Grant

The preliminary modifying factors for future stope design in the Southern Mine Area of Olympic Dam consisted of only a single, arbitrary value of Equivalent Linear Overbreak/Sloughing (ELOS). In order to improve this, a study was conducted which developed a more comprehensive methodology for assigning ELOS, Equivalent Linear Lost Ore (ELLO) and Equivalent Linear Fill Overbreak (ELFO) to individual stope faces based on geotechnical and mining parameters. The approach used was to look at the simple cases, which were classed as vertical stope walls in good ground (RQD 80-100%), divided into wall orientations (North, South, East, West). The stope walls were also split based on the blasting practice used (toeing, parallel or a combination of the two). The expected ELOS and ELLO from these ‘base cases’ are then modified by parameters which have historically been found to affect stope performance (Hydraulic Radius and Q’). The size of the effect found in the historical data determines the ELOS / ELLO applied. The methodology was summarised in an easy to use flow chart and was applied to all of the proposed stope shapes for the Southern Mine Area and summarised per mining block. This allowed each iteration of the mine plan to be assessed in terms of overbreak (both rock and vertical fill exposures) and underbreak.

Mar 15, 2021

By H Haghighi

Haul roads are often permanent unsealed access roads used by heavy haul trucks to transfer minerals. These roads can deteriorate rapidly which results in potholes, deformations and dust. Downer EDI Works has successfully provided efficient solutions to the mining industry to maintain their haul roads. HaulPac as a solution package is a process in which a bituminous emulsion is used to create a stable and durable pavement. The emulsion penetrates the road and binds the particles together, creating a stable base. It also seals the surface and prevents water from penetrating the underneath layers. Bituminous emulsion can increase the strength of the pavement material and decrease the road surface degradation which results in dust suppression. However, the everincreasing price of commodities, the necessity of reducing carbon emissions and the increasing use of autonomous haul trucks have made it vital to invest in novel maintenance solutions that can meet the needs of the mining industry in a cost-effective manner. This paper outlines the benefits of bituminous emulsion in terms of productivity, safety and environment followed by Downer’s approach to evaluate the suitability and to optimise the amount of product. The potential for changing the colour of the treated surface is explored and an initiative that incorporates end-of-life tyres of haul trucks into the pavement is introduced. And finally, an innovative method using artificial intelligence to estimate dust emission is presented.

Sep 18, 2023

By B Lance, D O’Brien

The Hidden Secret ore body is located within the Mt Charlotte underground mining system in Kalgoorlie, Western Australia. Mineralisation of the Hidden Secret ore body is lode style and therefore differs from the typical economical mineralisation mined at Mt Charlotte and consequently demanded a novel approach to the mining methodology. The ore body is lens like in shape, extending 200m along strike, 210m vertically, and dipping at 55 degrees. The lode width varies from 1.5m at the extremities to over 22m in the central zone of the ore body. Average grade is 3.4 Au grams per tonne. The initial mining methodology was Modified Avoca utilising Longhole Open Stoping with pillars, in a bottom up stoping sequence. However, as Hidden Secret became better defined and wider than initially modelled, it was identified that a high portion of gold would remain in the pillars and other mining concerns emerged such as remote backfilling large open voids and potentially unsafe vertical standoff distances between levels and wide open stopes. A re-evaluation of this method was undertaken and a new approach adapting a variation of Avoca methodology was identified to remove the rib pillars and replace them with a sill pillar separating the 4 levels into 2 distinct blocks. This new approach provided an immediate advantage by removing the bogger backfilling activity from the same level of the active stope front, enabling stope drilling and prepping to occur during the backfilling cycle. Bogging productivity has also improved as the fired ore is funnelled to the draw point by the backfill rill, significantly reducing the requirement for remote bogging thus improving bogging productivity. This mining method is currently in progress in the first of the two mining blocks and is on track to realise the targeted recovery of 7,700 ounces from the rib pillars.

Mar 15, 2021

By C M. W Boyle, E K. C Phuak, A Lewan, E Ryan, M D. Paine, P H. Mackenzie

"Rio Tinto Iron Ore (RTIO) has an extensive history in the application of geometallurgy to the iron ore value chain. Fundamental to this has been the geological logging of material types which are assigned processing attributes such as lump per cent and density. Initially these were used for product (lump and fines) grade predictions in relation to grade blocks to be used within short-term planning horizons.More recently the predictive reach of the material types and their associated processing attributes has been extended due to their inclusion into geological block models. These predictions can now be used to influence mine plans across multiple planning horizons in such a way that the extremes of geometallurgical properties can be pre-empted and managed thus improving efficiency. Spatial material type domains are also used in the planning of metallurgical drill holes to ensure greater representivity of material than was typically obtained by chemical and/or stratigraphic criteria alone.Material type logging has also been enhanced by the introduction of modern, rapid mineralogical techniques that have complemented visual logging. This has enabled the identification and quantification of contaminant minerals and their relationships with host ore types to be established. This data is used to better manage product grade predictions and identify risks to the short-term plan.Work is ongoing in RTIO to further refine logging based predictions and in addition apply them to new areas of the business. This work requires collaborative and multidisciplinary teams working on an integrated approach combining geology, metallurgy, technology and innovation, mine planning and technical marketing.CITATION:Paine, M D, Boyle, C M W, Lewan, A, Phuak, E K C, Mackenzie, P H and Ryan, E, 2016. Geometallurgy at Rio Tinto Iron Ore – a New Angle on an Old Concept, in Proceedings The Third AusIMM International Geometallurgy Conference (GeoMet) 2016, pp 55–62 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jun 15, 2016

Diamond drilling was first carried out at Norseman in the Princess Royal Mine, early in this century. Little concentl'ated drilling was done from then until Western Mining Corporation commenced drilling in 1934. Since then Central Norseman Gold Corporation N.L. has continually employed diamond drilling in exploration of the field. After 1946 the advantage was seen of applying broad pattern surface drilling at Norseman in the reef exploration. In 1953, as a result of the steeply rising cost of drilling and the time taken to penetrate surface material by light equipment, heavier drills and new rigs were introduced. The surface drilling programmes called for a greater monthly or annual footage and to satisfy this new techniques were introduced. The Mitchell-21 machines were discarded and A-3000 machines were installed, firstly under a 48 ft. fixed tower, then mounted on a truck with a 20 ft. tower, and finally on a truck carrying a 40 ft. tower. With the mobile units a compressed air compressor is attached. By use of compressed air with either the Reed roller or Hawthorne bit, rate of penetration of overburden is greatly increased. The mobility of the truck mounted machines has greatly reduced the time required to move from one hole to another, and the use of heavier machines on a three shift per day basis has considerably increased the footage per shift. The general result is an increase to 1,500 ft. of drilling per month per machine, while costs have been greatly reduced in spite of increased wages and diamond prices.The underground drilling technique is described. Analysis of performance has not been made because the drillers performance is subject to shaft routine and service.INTRODUCTIONGold was first discovered at Dundas in 1894, and at Norseman, 14 miles north, in 1895. From that tirpe until 1935 mining activity fluctuated. Following the mining revival in 1935, production in the field has remained comparatively stable. This stability in part has been due to the broader scale of operations of Central Norseman Gold Corporation N.L., and in these operations diamond drilling has played an increasingly important role.

Jan 1, 1956

Throughout the study phases (scoping, prefeasibility and feasibility) of new mining projects one is forced to work with and make predictions based upon limited date obtained from diamond and reverse circulation drill holes. These data are extrapolated to determine how much of the valuable metal is present in the ground, how it can be recovered it and the efficiency of this recovery. Mining methods to extract the ore are investigated with forecasts made regarding excavation stoping stability and performance in an attempt to optimise production. Extraction and use of rock mass data for use in characterising the mechanical behaviour of the rock mass is no exception. One often relies heavily upon the use of empirical charts developed over many years on hundreds of case histories based upon rock mass characterisation schemes. This is largely successful and indicative of what one might expect. However specific site characteristics can always play a significant role, and are not necessarily apparent in diamond drill core. Feasibility studies for the Favona orebodies indicated that the rock mass was generally poor to extremely poor, and that stoping conditions would be difficult in all of the orebodies for various reasons. A range stope performances were achieved ranging from very good to very poor and in some cases unexpected results were achieved. A comparison is made between what was actually achieved and what was expected since stoping commenced in 2007. Explanations are attempted for differences in stoping performance and, in some cases, unexpected results at the Favona underground mine are attempted.

Nov 25, 2010

By S Dunham

For decades we’ve been focusing on reconciliation as a tool to validate mineral resource estimates. And for decades we’ve been misleading ourselves. The concept of reconciliation is simple. Predict, measure, compare and assess the quality of the prediction. This four-step process reflects the ideas of statistical process control and the plan-do-check-act cycle of Shewhart and Deming fame and our intuitive understanding of using system feedback to improve performance. In an ideal world where data is robust and dense this type of feedback loop can be useful. In the mining industry however, there are some fundamental flaws with the conceptual framework. At almost every stage of the process from pre-estimation through to final production the mining system is plagued by material challenges with data and measurement quality and quantity, system delays, and losses from a supposedly closed system. These issues can and do impact on the benefits sought from reconciliation. Instead of providing feedback leading to improved estimation, reconciliation can result in poor decisions, distracting investigations, and exacerbate the noise in an already noisy system. Before we can rely on reconciliation as a management tool, we need to address the multiple challenges present in our everyday practices. Some of the most critical issues are addressed in this paper.

May 24, 2023

By P Klaric

Drive stability is critical in block/panel cave mining. The production levels of these mines are required to remain operational for the entire life-of-mine which can be in excess of 30 years. It is therefore necessary to produce high-quality drives to ensure sustainable mine productivity. In order to improve the quality of drives and pillars, this gold mine instigated a project to optimise their development blasting. The initial aim was to reduce the level of overbreak in development mining, which was averaging approximately 18 per cent. The benefits of controlling overbreak not only included an increase in the integrity of the drives but also a decrease in load and haul and ground support costs. Through focusing on the optimal blasting of the perimeter holes, overbreak was reduced to 4.5 per cent. The project’s focus then moved to drill and charge designs for development faces. In optimising these designs, it was anticipated that improvements in the development mining cycle would be achievable.CITATION:Klaric, P, 2015. Improving drive stability through efficient development blasting design and practices, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 327–332 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By S Thacker, M Noakes

The Newmont Tanami Operations (NTO), formerly the Granites Gold Mine, commenced operation in the mid-1980s with tailings deposition evolving over the past three decades as production has increased and the operation has expanded. Paddock-style tailings storage facilities (TSFs) and in-pit tailings deposition have fulfilled the tailings requirements for NTO over its lifetime with the technical specifications of these facilities improving over time in line with the positive development of standards, guidelines and best practice.This paper reviews the options for tailings storage facilities at NTO and the many considerations that have been analysed and deliberated upon before settling on specific TSF types and designs. It also explains the operating philosophies of the tailings deposition and how the facilities have always strongly maintained the optimum capture and retrieval of water. The current TSF design and criteria is presented, along with the introduction of dry tails harvesting for use in paste production as a backfill product for the underground mine. Tailings deposition and recovery remains a critical function of the Granites process to ensure long-term operation and gold production.CITATION:Thacker, S and Noakes, M, 2015. Newmont Tanami Operations – tailings storage facilities, in Proceedings Tailings and Mine Waste Management for the 21st Century , pp 305–314 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 27, 2015

By M Creech

During the 1990s, wider and more productive longwall panels were being introduced into the Newcastle Coalfield. The strata of the Newcastle Coalfield incorporate numerous massive sandstones and conglomerates, some of which formed the immediate roof of the coal seams being mined. The unexpected implications of introducing wider panels into this geological environment included more variable and increased subsidence, severe periodic weighting (with associated mid-face falls) as well as windblast.Subsidence prediction at the time was based on empirically derived data essentially relating subsidence to the width/depth ratio of the panel without accounting for actual widths, nor the impacts of variable geology. This approach required modification as locally derived data was gathered and reinterpreted.The interaction of massive strata located close to the roof of the mined seam resulted in dramatic implications for some of the operations. When associated with longwall goaf geomechanics severe periodic weighting events and crippling mid-face roof falls were the consequence. When associated with narrower panels and shortwall goaf geomechanics, mines in the region experienced aggressive windblast events. The relationships between the overlying massive strata, longwall panel geometry and the various risks encountered during this period is in the author’s opinion, the most concise still documented.As the extensive coalfields of Queensland turn to underground mining operations the relevance of these experiences cannot be underestimated. This paper will discuss recent developments as well as incorporating diverse subjects such as microseismic monitoring, low frequency radio emissions and ‘electrophonics’ as they relate also to the topic.Like Moriarty, massive strata can be disguised and can offend when you least expect. This paper documents a trail of crimes committed by conglomerate in the Newcastle Coalfield that were inflicted on the general public, miners and mining equipment. Although this paper concentrates on the criminal behaviour of conglomerate, this story is also relevant to other massive units such as coarse sandstones that may be more difficult to identify and apprehend. Currently Moriarty remains at large and able to reoffend at any time, once again taking advantage of the unwary.CITATION:Creech, M, 2014. Moriarty was a conglomerate – experiences and implications of coal mining under massive strata in the Newcastle Coalfield, in Proceedings Ninth International Mining Geology Conference 2014 , pp 47–54 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 18, 2014