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The sedimentery basins of this region developed in the collision zone of the Pacific Ocean plate and the continent. Stresses were transmitted thorough wedge-like lithospheric blocks, such as the Okotsk Sea, East Kamchatka, Aleutian and 2 other smaller blocks. Compression and inversion were more active at the boundaries: P ; P3 ; N1 ; and Z N in places. ? K2 P2 P3 N2 Tension, rifting and the increase in the rate of sedimentation were marked in '-2 , P3, Ni - N2, and also N2 - Q in places. Structural plan changes of the sedimentary basins and possible oil, gas and fluid migration occurred more actively 2 3 1 2 at the boundaries: ; P3 . N? , N1 N1 NZ N2 P2 P3 1 N1 'N 2 N3 Ni 1 1

Jan 1, 1995

The City of KalgoorlieBoulder is situated approximately 600 kilometres to the east of Perth, and as the major regional centre of the Eastern Goldfields, supporting a population of approximately 25 000. The formation of Kalgoorlie Consolidated Gold Mines in 1989 brought the existing operating entities adjacent to the city under common ownership and management. The Joint Venturers forming the management company are Homestake Gold of Australia and Gold Mines of Kalgoorlie (a Normandy/Poseidon company).This traditional underground mining centre has been worked since 1893, yielding 40.5 million ounces of gold ore with an average head grade of TEN grams per tonne. Historically the heart of the operation has been the famous Golden We located on the Eastern perimeter of the city, in the area known as Fimiston. The other significant operations that form KCGM are the Mt Percy Open Pit and the Mt Charlotte Underground Operation.

Jan 1, 1992

By B Huls, B E. Smith, I Brake, M Yu

A brief outline of some of the pioneering events in the development of flotation technology, which originated in Broken Hill at the start of the 1900s, is presented. The development of the original Potter-Delprat process, the introduction of oils to generate froth flotation and the achievement of selective flotation processing are described, all focussed on solving challenges with the Broken Hill Pb-Ag-Zn ores. Some recent initiatives in flotation at BHP Billiton operations are also outlined, covering coal, copper, lead-silver-zinc and diamonds. Some views are offered on the characteristics of innovation in flotation and on possible trends into the future.

Jan 1, 2005

Solid Energy New Zealand Limited (æSolid EnergyÆ) is a state-owned coal mining company, producing 4.0 Mtpa from a number of opencast and underground mines in the Huntly, West Coast and Southland regions in New Zealand. The company currently exports 2.1 Mtpa of coking coal. Exports are expected to grow strongly over the next five year as the company expands production into new semi-soft and thermal coal reserves. Domestic coal demand is also expected to grow strongly, particularly in the North Island, as the Maui gas field reserves diminish, and thermal coal becomes more important for electricity generation and meeting the energy needs of forest processing and other industries. Solid Energy is expanding and developing its risk management practices across all areas of the business: strategic planning û extensive use of scenario analysis and probabilistic modelling over a 20 year period; investment decisions û development and application of a rigorous six stage æProject Assessment GuidelineÆ process for all new mine developments; geological and geotechnical risk assessment techniques û use of best practice techniques including seismic surveys; financial risk management û a dynamic approach to hedging based on effects based analysis of Cash Flow at Risk analysis against preset risk tolerances; risk financing û the use of a captive insurance subsidiary, and the experiences of a small coal company seeking to obtain insurance cover on a æhardÆ international insurance market; and integrated risk management û the challenges of trying to implement a broad integrated risk management approach across the company, that supports implementation of strategic objectives as well as meeting æcompliance or legislative basedÆ risk management requirements.

Jan 1, 2003

By L B. Zhou, S Li, B L. Wang, S B. Li, Q Wang

The rapid development in ChinaÆs metal mine resources has caused a series of mine environment problems such as serious ecological damage and environment pollution, and secondary geological disasters. The paper has reviewed ChinaÆs metal mine development, including current status and environmental situation, analysed existing problems in mine development and environmental management, and proposed corresponding countermeasures and suggestions.CITATION:Wang, B L, Li, S B, Li, S, Zhou, L B and Wang, Q, 2012. Current situations, problems, countermeasures and suggestions for ChinaÆs metal mine development, in Proceedings Life-of-Mine 2012 , pp 353-356 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 10, 2012

By D Stacey, J Matthews

Hunter Valley Operations in partnership with Orica Explosives designed a process to optimise coal extraction at depths greater than 65 m below the Hunter River in a safe and cost effective manner. The process involved a team approach to investigate the relationship between geology, mining sequence, vibration and blasting methods adopted. From this an optimum method for uncovering the coal was developed.

Jan 1, 2001

By A Hosseinzadeh Barforoosh, A Abedi, M Taji

The effect of blast loads on beams is one of the main issues in the analysis of steel structure. In this study, experimental tests on steel beam under blast loading, and also numerical simulation by the Autodyn software to analyse these structures, is discussed. Experiments on steel beam size of 12 by Emulite4 explosive with 30 mm diameter and cortex is done. The patterns of cutting and bending generated in the two tests (empirical and simulation) show a good match.CITATION:Taji, M, Hosseinzadeh Barforoosh, A and Abedi, A, 2015. Comparison of experiment and simulation of blast loading on the steel beam, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 161–168 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By P Swart, A Fletcher, P D. Erskine

Glencore Coal Assets Australia (GCAA) operates five coalmines in Queensland and has rehabilitated thousands of hectares of mined land across these sites. Accordingly, GCAA seeks to continually improve rehabilitation outcomes over time and work towards progressive rehabilitation sign-off. The ultimate test of rehabilitation success is the attainment of an agreed land-use target, whether for biodiversity conservation or some type of agricultural production, and the ability of the rehabilitated landscape to resist degradation and retain desired functions (eg biodiversity protection or grazing productivity). However, success must be based on documented evidence that can demonstrate adequate progress towards rehabilitation targets and is assessed at appropriate intervals. To assist this task, a stepwise decision guide for the GCAA monitoring program was developed to ensure consistent monitoring data is collected across the range of sites. This presentation will discuss some of the processes that were followed to allow GCAA to identify appropriate metrics to assess rehabilitation success efficiently over thousands of hectares.CITATION:Erskine, P, Fletcher, A and Swart, P, 2016. Preparing for progressive mine rehabilitation sign-off in Queensland, in Proceedings Life-of-Mine 2016 Conference, pp 148–150 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

By P K. Seccombe

Sulfur isotope data are available for 18 low-sulfide orogenic gold systems hosted by the Lachlan Orogen in eastern New South Wales including those in the northern Hill End Trough (Hargraves, Hill End, Napoleon Reefs, Sofala-Wattle Flat, Stuart Town, Windeyer) and adjacent areas (Bodangora, Lucknow, Springfield), the Gilmore Fault Zone (Adelong, Sebastopol) and those in the Parkes district (Calarie, London-Victoria, Wyoming One-Myall United). Other systems for which data are available include Mongarlowe, Murrumbateman, McMahons Reef and Yalgogrin. The d34S data for many of the larger deposits including Adelong, Bodangora, Calarie, Hargraves, Hill End London-Victoria, Lucknow, Sebastopol, Sofala-Wattle Flat, Stuart Town and Windeyer (Group 1) are all very similar and have average d34S values close to zero per mil. Near 0ë d34S signatures imply that sulfur was sourced from a magmatic reservoir. Furthermore, the large Wyoming One deposit has d34S values significantly below 0ë with the data implying that sulfur was sourced from a fractionated magmatic reservoir. Group 2 deposits include those at Mongarlowe, Murrumbateman, Napoleon Reefs, McMahons Reef and Springfield . These deposits have average d34S values significantly above 0ë. With the exception of Springfield where sulfur was probably sourced from the Hill End Trough, Group 2 deposits are an order of magnitude smaller than Group 1 deposits. The results suggest that many of the larger orogenic-related gold deposits hosted by the Lachlan Orogen in eastern New South Wales derived sulfur and gold as a result of leaching and recycling from a magmatic reservoir. Alternatively, there may have been direct mantle-derived input; however, this is considered unlikely on geological grounds. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008

Natural gas was introduced to the Melbourne reticulation system in April 1969 and since that date sales to industrial consumers in the Gas & Fuel Corporation of Victoria area of supply, have increased by over 50% This increase has occurred despite the fact that the areas in which the new fuel is available have been dependent on the progress of the conversion operation from manufactured gas. The half way mark for conversion was reached in May 1970. The reason for the adoption of natural gas by industrial users is usually the result of objective financial analysis leading to the conclusion that the new fuel will give the lowest overall production cost. Many factors are involved in such an analysis of which the price of the fuel is only one. Amongst other important elements in the cost calculation are:- -ò òò -(1) The effect of fuel on product quality (2) Maintenance and handling costs for alternative fuel. In addition to economic gains for the individual user, the use of natural gas should benefit the whole community through its effect on such things as, air pollution and overseas balance of payments.

Jan 1, 1970

By Katsuyama K, Nag DK

Three aspects of rock mechanics, namely, in-situ stress estimation by acoustic emission (AE) method, strength of rock mass and role of chemicals to reduce the strength are covered. It is possible to detect the previously applied maximum stress by stressing a rock specimen to the point where there is a substantial increase in AE activity. This is known as Kaiser effect. From the AE signatures in the second and subsequent loadings, AE take-off point was identified more easily than in the first loading. In determining the compressive strength of rock mass, two factors have to be considered, namely, the size effect on the compressive strength of intact rock and the effect of discontinuities on the compressive strength of rock mass. Although a modified Bieniawski criterion gives best agreement with the triaxial test data, modifications have been suggested to Hoek-Brown criterion due to its popularity. It is possible to reduce the tensile strength of sandstone by saturating it with weak chemical solutions made with dodecyltrimethyl ammonium bromide, polyethylene oxide and aluminium chloride by up to 30%. In the case of compressive strength, there is no appreciable effect. The possible explanation is that the chemical solutions produce an effect on the strength of sandstone only when the failure mechanism is dominated by tensile mode.

Jan 1, 1998

The Charters Towers 1:250 000 Gravity Data Set represents a new initiative of the Department of Resource Industries (DRI, formerly Queensland Department of Mines) to provide high quality regional gravity data over areas of the State that have high potential for new mineral discoveries. The Department has adopted a strategy to upgrade geophysical data to complement the ongoing Regional Geological Mapping Program (RGMP) of this Department and in areas where the data would be of most benefit to the mineral exploration industry. Part of this strategy is to ensure that these data are released within 6 months of data collection.The 1989 Charters Towers survey was completed as a joint project with the Bureau of Mineral Resources, Geology and Geophysics (BMR), and is the first regional geophysical data acquisition project undertaken by the DRI. Prior to this survey, the only gravity data in this area dates from the B MR regional surveys carried out between 1960 and 1967.

Jan 1, 1990

By Fourney W. L, Dick R. D

Tests were conducted in plexiglass and Rockite models to determine if crater blasting could be improved by changes in charge geometry or by alterations to the borehole. Circumferential grooves were placed at various locations in the borehole in an attempt to control the initiation site of the crater. Grooves located at or above the top of the cylindrical charge had no effect on the resulting crater. Grooves placed too low in the borehole were successful in controlling the initiation site but the growth of the fracture system was not sufficient to reach the upper surface. Grooves located at a height of two thirds of the charge length were quite successful in that resulting craters were bigger by at least a factor of six than the normal crater. Testing was conducted in Rockite models to investigate charge geometry. Spherical charges in ungrooved boreholes resulted in crater sizes that were three times larger than those caused by cylindrical charges.

Jan 1, 1990

By A S. Derrington

In some parts of Australia, mine air cooling may not be needed until a depth of 1300 m below surface is reached. In other locations, it may be essential at a depth of only 300 m below surface. The reasons for these differences are multifaceted. This paper discusses the main factors and describes a simple method to assess whether or not mine air cooling will be required. The method uses a graphical relationship that considers depth below surface, geothermal gradient, surface climatic conditions and directness of the mine intake routes. This relationship has been developed, tested and refined over a period of more than ten years using data collected from most of Australia’s deeper metalliferous mines. The method provides a ‘first-pass’ indication of whether more detailed cooling studies may be needed. Perhaps more importantly, the method’s underpinning by benchmarking against other mines improves confidence in the assessment results. Like any empirical method, the context must be understood and this aspect is also discussedCITATION:Derrington, A S, 2014. Will your mine require cooling?, in Proceedings 12th AusIMM Underground Operators’ Conference 2014 , pp 181–186 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Mar 24, 2014

By L Xiong, W J Shi, J H. Wei

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Baizhangzi gold deposit is located in the northern North China Craton. The structural and lithological controls on the location and geometry of orebodies were studied through geologic survey, ore spatial configuration analysis and structural analysis. The orebodies of the deposit comprise auriferous quartz-sulfide veins and disseminated gold-bearing sulfides. The auriferous quartz-sulfide veins are dominantly hosted by the NNE- (and NE- and NW-) trending faults, which are subsidiary structures of the regional NNE-trending F2 fault. The subsidiary NNE-trending faults, having sinistral reverse kinematics, are associated with the sinistral reverse kinematics event of the F2 fault, which happened under a regional S–N-oriented compression stress field. The subsidiary NE- and NW-trending faults appear to be compressive and extensional respectively. These NE- (and NW-) trending faults are restricted to the granite intrusion and are associated with a sinistral strike-slip event of the F2 fault, which reactivated under a NW–SE-oriented compression stress field. It makes significant influence on geological evolution and distribution of different ore types that the strike of the F2 fault presents significant transition from NNE- to NE-trending in vertical. The ore-bearing disseminated host rocks, with widespread silicification and pyritisation, distribute in the lower inner contact zone of the granite intrusion, especially in the lower wavelike boundary of granite intrusion.CITATION:Xiong, L, Wei, J H and Shi, W J, 2015. Structural and lithological controls on the location of orebodies in the Baizhangzi lode gold deposit in western Liaoning Province, China, in Proceedings PACRIM 2015 Congress, pp 193–200 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By E Wargem

The optimum mining of an orebody in an underground mining operation is fundamental to the mine’s ability to operate both sustainably and efficiently. The effective mining of an open stope or a cave is largely reliant on the recovery of the initial void created by conventional drilling and blasting. These initial voids are known by various names such as a Longhole Rise, Slot or Winze and can be mined either as a downhole or as an uphole. Regardless of the underground mining method, the process of the design and implementation of this initial void is largely uniform across many operations with various patterns of slot or winze designs used across these different operations. Diligent design, implementation and review strategies in drilling and blasting of these will facilitate cost-effective mining with minimal disruption to mine schedules and production targets. When an operation struggles in opening the initial void in underground mine blasting, it has a negative impact on productivity, mineral recovery, and the overall economics of mining. Near field blast vibration monitoring is a vital tool to use in analysing slot blasts and will provide additional feedback into the reconciliation part of the drill and blast process. It is one that is often overlooked in the mining industry in many operations due to many factors such as lack of skilled personnel, or a lack of required resources. The data obtained from near field blast vibration monitoring can be used to provide additional feedback into blast reviews and help in any drill and blast optimisation projects. This paper highlights key aspects of underground drill and blast reviews and the use of near field blast vibration monitoring for post blast analysis and shares learnings from various projects that the authors have been involved in within Australia and abroad.

Mar 29, 2023

By C Artica

Two quantitative methods for Mineral Resource classification have been applied to a copper skarn deposit beneath a large open pit that is mining a world-class porphyry complex. A drill hole spacing study (DHSS) using the single block kriging method (SBK) and a conditional simulation method (CS) were applied to the skarn deposit and the results compared. Inputs to both processes included the proposed mining rate and stope designs to estimate the likelihood of achieving grade and metal production targets. Mineral Resource classification of the deposit considers the relative precision of tons, grade and metal predictions over quarterly and annual production periods. These relative precision estimates are calculated at 90 per cent confidence interval (CI). The SBK method represented the production period as a single large block. Kriging estimates were performed in the large block for various synthetic drill hole grids, and the estimation errors derived. The error was assumed to be normally distributed due to the large block size and quantity of samples, allowing CIs to be deduced. The CS method followed a conventional sequential Gaussian simulation workflow where grades were simulated with a 5 ft × 5 ft × 5 ft grid node spacing inside mineralisation domains. Each realisation was then averaged up to monthly production volumes represented by a combination of designed stopes, and the coefficient of variation (CV) for the averaged grade was calculated. CI on the relative precision of grade predictions were then deduced from the CVs. The two methods produced similar results; despite being calculated independently. CS results were used to report uncertainty in the proposed life-of-mine plan and highlight areas for additional drilling. SBK results were used as the basis for Mineral Resource classification as this method has been previously applied to the skarn deposit.

May 24, 2023

By M Wagner, H Assimi, F Neumann, C Garcia, B Koch

Run-of-Mine (ROM) stockpiles are the inventory of valuable materials extracted from the mine. Depending on the customer requests, a selective addition of ore from stockyards should be selected at the required tonnage. In the stockyard, stackers and reclaimers are the machines which load and unload ore, respectively. Currently, humans determine the reclaiming/stacking planning sequence in the stockyard by rules of thumb. However, this is a complex task subject to multiple operational constraints, such as where undesirable mineral properties should not exceed certain limits in a request. Human planning can lead to limited decision support and lower ability to consider the upcoming blends and requests. This kind of decision making can cause perturbations in the assumed profit and unexpected loss in practice. Therefore, an intelligent decision-maker and sequence planner would be highly valuable to automate stacking and reclaiming operations in practice. The benefits are reducing variability in decision-making and operation costs. This paper considers a stockyard with available mineral information in the stockpiles using load and dump locations from GPS data feeds. We present an optimisation problem to find a solution which results in reclaiming more ore in a shorter time. To solve the problem, we develop an automatic search strategy based on the greedy search algorithm independent of the type of machine used in reclaiming. The proposed method plans a sequence for stockyard recovery blend optimisation to meet multiple customer demands in a timeframe. Blend optimisation is subject to various constraints such as the elemental composition of the valuable materials and penalty elements. We present three case studies using EKA’s simulator, to fulfil two to four requests from four stockpiles. We compare the obtained results with a pilgrim step reclaiming heuristic and we show how our proposed search strategy outperforms the current strategy used in practice.

Nov 10, 2020

By K Brand, M J. Ind, M Rynhoud

Water management at a tailings storage facility (TSF) presents one of the major risks to the safe performance of the facility. International and domestic dam safety guidelines assess a dam’s hazard category based on the consequences of a dam failure and the subsequent downstream damage to the environment and communities.Often a rigorous risk assessment is undertaken during the design stages to identify and control hazards associated with water management through life-of-mine (LOM) phases. However, as experienced during the recent downturn in commodity prices, early closure of a mine can occur rapidly and unexpectedly. Although guidelines such as the Australian National Committee on Large Dams Incorporated (ANCOLD) recommend that one of the key objectives of integrated TSF planning is to ‘plan all phases of a tailing dam’s life to ensure adequate storage capacity including early closure ’ (Australian National Committee on Large Dams Incorporated (ANCOLD), 2012) this is often overlooked by owners who are focused on fulfilling the mine’s potential and early closure is not on their radar.CITATION:Ind, M J, Rynhoud, M and Brand, K, 2016. Life-of-mine spillway strategy – managing risk associated with surface water at a tailings storage facility, in Proceedings Life-of-Mine 2016 Conference, pp 209–211 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jun 28, 2016

With the iron ore industry in Australia producing hundreds of millions of tonnes of ore per annum, the associated costs of these operations extend into the billions. It is no surprise in the current economic climate that more and more companies are looking into different ways of optimizing their costs to keep their sites operational. One way of improving operations is the use of electronic initiating systems like i-kon and Uni tronic detonators. These systems have been used around the world to improve current practices and optimize drill and blast costs. However, these systems have yet to make an impact upon the iron ore sector in Australia. Some of the potential improvements include:pattern expansion and a subsequent reduction in drilling and explosive costs;improved fragmentation and hence increased dig rates, thereby driving $/tonne down;embracing the 'mine-to-mill' concept by reducing the downstream costs of crushing and milling;improving the overall condition of pit walls and floors, leading to a safer working environment in which optimal haulage performance can be achieved; and improvements in vibration management around heritage sites and critical infrastructure, thereby saving the cost of relocation works. This paper introduces some of these concepts and the process of making the changes leading to potential savings from the improvements, using various examples as proof of the concepts.

Jan 1, 2009