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By Y Tsukurimichi, D Asahina, T Endo, T Takemura

Scientific knowledge of Mars’ surface morphology and internal geological structure has been accumulated through satellite imagery and numerical topographic data using remote sensing technology, as well as seismic surveys by the on-site lander. Recent studies show that Marsquakes could be caused by the release of strain energy generated by the contraction of Mars. In particular, Marsquakes occur around the graben where many faults are existed and formed regularly spaced patterns. This implies that Marsquakes occur when the stress field of the Martian crust is an extension condition, and normal faults appear on the surface. We focus on the linear relationship between the fault spacing and the thickness of the mechanical layer as an approach to studying the internal structure from satellite images. Mechanical layer is a layer that composes of the same mechanical properties and is mainly bounded by lithology (Narr, 1991; Gross, 1993). The linear relationship between the thickness of the mechanical layer and the joint spacing has been studied and its slope is called the Fracture-Spacing Index (FSI) (Narr and Suppe, 1991). Soliva, Benedicto and Maerten (2006) showed that the stress drop zone (stress shadow) due to the fault activities affects the fault spacing. Figure 1 shows the approach used to estimate the thickness of the mechanical layer from the fault spacing on Mars. This paper aims to better understand the internal mechanical structure of Mars estimated by the geometrical pattern of faults on the Martian surface. We report the initial studies of this work. The lab-scale physical experiments and numerical experiments were presented to demonstrate the relationship between the thickness of the mechanical layer and the geometric pattern of fractures

Nov 29, 2022

By K Nguyen

The advances in computerised processors and digital microscopic imaging have enabled more studies that attempt to quantify textural information from rock images. However, a texture classification system designed for geometallurgy has always been challenging, as it combines general image analysis techniques and specific texture classifications in terms of the size, shape and orientation of mineral particles. In this paper, a novel texture analysis technique using grey level radial shell association (GLRSA) and spectral angle mapper (SAM) to discriminate between different geological images is outlined. The technique can be applied in routine analysis and characterisation of mineralogical and textural attributes which may correlate with variability in mineral processing behaviours. Using this texture analysis technique, a set of small texture reference images, a texturelet reference library, has been identified from a suite of drill core images. Rock types are classified according to the proportion of each texturelet type recognised. The library is site specific.CITATION:Nguyen, K, 2013. A new texture analysis technique for geometallurgy, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 187-190 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

We all live in professional silos û comfort zones, where we talk to like-minded people with the same training, experience and view of the world. We note in passing the existence of other disciplines, but they are tolerated rather than embraced. To the geologist, the metallurgist is a mad scientist conjuring gold out of some foul solution about which the less said the better. To the metallurgist, the geologist is a bearded, self-appointed sage who guesses what is under our feet by sniffing the air, and drives a Land Rover badly. As to the view of mining engineers held by both geologists and metallurgists, this is best left to the imagination. And of course we are all confused by the term æmetallurgistÆ. I am called a metallurgist though my skills are in mineral processing not metal processing, but I canÆt be called a mineralogist because that definition is already taken. *Please note that this is available as an extended abstract only*

Jan 1, 2005

Synthetic and commercial activated carbons are characterised for several chemical and physical properties. A range of techniques is used to establish correlations between physicochemical parameters and gold- adsorption activities. The most important parameter in the carbon activation process for a product with a high gold-adsorption activity is the activation temperature. High activation temperatures yield products with large micropore volumes which provides sites that are ideal in size for adsorption. The surface area of an activated carbon is not necessarily a good measure of its adsorption activity. Surface oxygen-containing functional groups are identified by Fourier transform infrared spectrophotometry to be comprised mainly of ethers and hydroxyls. These functional groups line the edges of the micropores imparting a polar character to the pore and aid in the solvation of the adsorbate. Oxidants such as nitric acid result in a proliferation of surface carboxyl groups. resulting in a negatively- charged surface that is not conducive to the adsorption of gold.

Jan 1, 1993

Silver-lead ores are widely distributed through- out the Mount Lofty and Flinders Ranges, but none of the deposits is large. Historically the Glen Osmond Mines are the most significant as the site of the first metalliferous mining in Australia, but Talisker was one of the three largest producers of silver-lead in a state whose mining history is dom- inated by copper. The mine is located in a magnificent natural setting on Talisker Conservation Park, near Cape Jervis, southwest of Adelaide (Figure 1). It is exempt from the operations of the Mining Act and listed on the Register of State Heritage Items. The mine and associated township of Silverton were dominated by Cornish influences during the period of principal activity between 1862 and 1872. Silverton, located on a ridge overlooking the mine, grew to a population of about 300 at its peak in 1870 and the area was very much another 'little Cornwall'.

Jan 1, 1987

By R Trueman

An improved ability to predict dilution for narrow vein deposits enables more accurate economic comparisons between mechanised longhole stoping and other narrow vein mining methods, as well as reducing uncertainty surrounding dilution estimates for deposits at the prefeasibility/ feasibility stage. This paper proposes narrow vein dilution prediction and minimisation strategies for both greenfield sites and operating mines, respectively. The narrow vein dilution method (NVD method) is a tool for more accurately predicting longhole narrow vein dilution. The method is based on a new concept called benchmark stoping width. Benchmark stoping width is based on probabilistic analysis of overbreak distributions from a typical longhole narrow vein mine. The premise for the NVD method is that dilution associated with longhole stoping can be predicted using the benchmark stoping width. In addition to dilution prediction, the NVD method also includes strategies for narrow vein dilution minimisation generally, including; filling, cablebolting, stress relaxation, extraction sequencing and blast overbreak.

Jan 1, 2008

By S Hapugoda, M Peterson, A Haileslassie, A Poliakov, E Donskoi, L Lu

Most metallic iron in the world is produced in blast furnaces from different feed stocks – sinter, lump ore and pellets. Sinter is the main iron-containing feed to the blast furnace and can constitute up to 70–85 per cent of the total ferrous burden. As sinter quality is a key element for stable blast furnace operation, the textural, chemical and physical characteristics of the sinter are very important. Two major factors that affect sinter strength are mineralogy and porosity. This study utilised optical image analysis (OIA) to characterise sinter mineralogy, and the results were compared to those obtained by manual point counting under the optical microscope.Two major mineral characteristics of iron ore sinter are the presence of primary (unreacted) and secondary (derived from melt) hematite. Standard OIA, which is based on RGB thresholding, is not able to distinguish them as they have the same reflectivity; however, primary and secondary hematite in iron ore sinter have a different morphology. The CSIRO-developed OIA software Mineral4/Recognition4 has a unique feature to identify various textures/morphologies of the same mineral. Together with other capabilities of the Mineral4/Recognition4 software, this feature was used to identify different types of hematite and silico-ferrite of calcium and aluminium and other common sinter phases, such as magnetite, larnite, glass and remnant aluminosilicates.A visual comparison of the sinter mineralogy present in optical photomicrographs and that present in the mineral maps created automatically by the Mineral4 module of the CSIRO software confirmed the accuracy of the automated mineral identification.CITATION:Donskoi, E, Hapugoda, S, Lu, L, Poliakov, A, Peterson, M and Haileslassie, A, 2015. Advances in optical image analysis of iron ore sinter, in Proceedings Iron Ore 2015, pp 543–548 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

This paper describes the planning mechanism and implementation of a progressive rehabilitation programme at Hunter Valley Mine in the Upper Hunter Valley of New South Wales. Hunter Valley Mine is a large open cut coal mine which produces approximately 7.0 million tonnes of coal (run of mine) annually for export. This production level involves the movement of some 60 million tonnes of waste and coal each year.The rehabilitation programme at Hunter Valley Mine has been developed to provide a combination of pasture, based on improved pasture species and timber belts to enhance the visual characteristics of the rehabilitated landform, whilst creating amenity in the form of shade for livestock.The operational philosophy for the rehabilitation programme is that of progressive rehabilitation. The best time to undertake rehabilitation is now.' As a result, planning for the rehabilitation programme is continuous, so that all site works are completed in time for vegetation establishment during the critical periods each year.

Jan 1, 1992

By S Prakash, M Danish, D Kumar

The green energy transition is speculated to cause an increase in the demand for raw materials while recycling rates are improving; discoveries are required to maintain supply. Geological remote sensing offers a cost-effective way of exploring mineral resources. While satellite and airborne imaging are routinely used for exploration targeting, a gap remains at the outcrop scale. Hyperspectral imaging (HSI) is advantageous for large-scale regional mapping, typically performed from satellite or airborne platforms. Accurately mapping geological lithologies remains challenging in inaccessible areas, such as rough terrain or mine sites. Proximal sensing techniques can boost geological activities’ reliability, safety, and efficiency in exploration or during mining activities. It also generates objective, reproducible results and valuable raw data that can be archived, further processed, and re-interpreted. Ground-based hyperspectral imaging of outcrops has steadily increased during the last decade due to sensor development and better processing routines. There is often a big technology gap related to mineral mapping, integration of images and spectra (reduction in manual identification of minerals and types) and hyperspectral data visualisation through remote sensing. TEXMiN Foundation, in collaboration with its industry partner Dassault Systemes Foundation, carried out the project, ‘Developing Hyperspectral Image Processing and Analysis, build a rich library of Hyperspectral images of a vast range of minerals from India which will help in increasing prediction accuracy of mineral deposit for mining exploration’.

Sep 1, 2024

By R Mackay, J Brereton

On 30 June 2020, the Mine Land Rehabilitation Authority (the Authority) superseded the Latrobe Valley Mine Rehabilitation Commissioner as the independent overseer of Victoria’s declared mine rehabilitation. Currently, only the Latrobe Valley’s three brown coalmines are declared, with each mine at a different stage of rehabilitation and closure planning: Hazelwood ceased mining in 2017, Yallourn is scheduled to end mining in 2028 and Loy Yang in 2035. The three declared mines are very large, close together (Figure 1) and present significant environmental risks that must be mitigated during rehabilitation and post closure. In addition to fire risks, the brown coalmines are inherently unstable and require continuous monitoring and management of ground movements and groundwater pressures. Since 2007 several damaging events have occurred, highlighting the difficulties of achieving long-term stability, even with good landform design and rigorous ground control management plans

Aug 2, 2023

By R Burgess-Limerick, D Lynas

A number of standards and guidance materials currently exist to assist equipment designers. The ISO process, however, is a formal process and change often lags behind technology development. In some cases, this may result in weak or ineffective standards that need to be written in general terms to accommodate future technology developments, meaning some standards may only establish minimum requirements and not be overly helpful to equipment designers, in particular when designing for workforce diversity and inclusivity. By contrast, advisory information as issued by various mining regulatory bodies is able to respond more quickly to changes in technology. Standards do however have a safety and productivity focus providing design consistency between equipment manufacturers, a basis for auditing purposes, assistance in mining regulation and compliance, and in the development and application of safety management systems. As an example of challenges facing equipment designers, ISO3411 (2020) provides data approximating the 5th, 50th and 95th percentile of the ‘earth-moving machinery operator population’ for numerous static dimensions relevant to the design of earth-moving equipment. These data are then utilised in ISO6682 (2020) to provide recommendations regarding the location of controls. Attempting to utilise the data provided in ISO3411 (or other sources of static anthropometric data) creates further challenges for equipment designers, in that reference percentiles is problematic for design purposes. There is no ‘5th or 95th percentile operator’ as individuals vary along each dimension (Robinette and Hudson, 2006). Although dimensions have some degrees of correlation, when multiple dimensions are considered, the range of individuals which fall within a given range on all dimensions reduces substantially. For example, only about 82 per cent of individuals in a population will fall within the 5th to 95th percentile ranges for both height and weight. The more dimensions are considered, the smaller the range of people who actually ‘fit’ the description.

Apr 16, 2024

The 1990s present many challenges, not the least of which is in the area of health and safety. Integrating of safety and health into the management process to suit the overall needs of a company will require commitment. Organisations which consistently perform to high success levels do so because they plan it that way. By using tools of total quality management, the potential to continually improve all safety processes exists. The successful integration of total quality measurement principles used in the improvement of safety processes, and the measurement of performance-based activities allow for prevention of accident causing scenarios and performance improvement.

Jan 1, 1993

By P Hanna

Following the Busang fiasco, more detailed guidelines were appended to the latest revision of the JORC Code released in September 1999 (JORC, 1999). Although the definitions and terminology essentially remained unchanged, the additional information in the guidelines has highlighted a number of issues for consideration by geologists undertaking computer-based resource estimations. The three main issues are:Data Integrity û details such as drilling and logging techniques, sampling procedures, assay tests, site visits, data recording and aggregation methods need to be considered. Geological Interpretation û is the Competent Person applying the appropriate software interpretation to the deposit in accordance with the regional setting. Are the correct computer-based tools being applied and are they producing the desired result (without compromise) to the satisfaction of the Competent Person? Modelling Technique û the importance of the relevant experience of the Competent Person not only in regard to the geology, but also with respect to the modelling algorithms and resource calculation methods of the computer software system involved. At the end of the day, it is essential that the Competent Person undertake a reality check on the resource estimation itself. They should also check that the borehole spacing is in accordance with the level of continuity for each critical parameter (such as structure, grade, impurities, etc) for which the resources are categorised.

Jan 1, 2000

By G R Ryan

Dissatisfied with conventional wet processing methods for alluvial deposits, Resource Trend Pty Ltd of Cairns set out to develop a better process. After comprehensive investigation of existing dry techniques the principals have now developed a rotary dry concentrator that can handle the fine-grained fraction of alluvial deposits as well as the coarse. Four of these units have been mounted on an integrated towable treatment plant which has been in successful commercial operation for four years in northern Queensland. A second plant is now under construction for use in the United States. Grades of less than 0.2 g/lcm have been profitably mined at throughputs of about 80 cubic metres per hour and 85 per cent availability. The operation runs round the clock with an establishment of four. Major benefits, apart from lower capital and operating costs, are environmental. Ore is picked up, treated, and replaced in its original mixed condition within 25 m of its initial location. Rehabilitation is completed almost immediately behind the plant as it advances, leaving no slimes dams, coarse stockpiles, or haul roads. In 1993 the company won a Premier's Award for Environmental Excellence in the Queensland Mining Industry. The principal disadvantage is moisture, and the company is now actively seeking deposits in the deserts of the world. In Queensland mining is normally possible only for six months of the year.

Jan 1, 1994

By C Deacon

It is common practice to include microspheres or similar density reducing agents in inherently insensitive water-based commercial explosives to achieve detonative sensitivity in the absence of chemical sensitisation. It has recently become possible to similarly include microspheres in LDAN (low density ammonium nitrate). Further to previous studies and publications to determine the benefits resulting from the use of microsphere enhanced LDAN technology in blasting, additional advantages are described in this document. These include range tests at independent testing facilities (Universal Tech Corporation û USA) which reflect results observed in the field, and support theoretical assumptions made when the products were introduced. Additionally, on-site studies in opencast pits using Heavy-ANFO blends incorporating modified LDAN, show that monetary savings can be realised through significant advantages gained in plant throughput and explosives use.

Jan 1, 1999

Although technology and circumstances are in a constant state of change, the principles of managing the human element remain constant. The isolated mining community continues to form the backbone of the minerals industry but the nature of the isolation, along with the economic and political environment of the industry, is changing. These changes require new inputs by management to the workforce. Management must determine an effective working relationship with unions on its mine site and concurrently contribute to the build- up of the expertise of the individual worker through training and communication. It must also retain a proper balance, by way of human contribution, in cost and information reporting and in other areas amenable to computerisation. These comprise the aids to management necessary to achieve the desired operating efficiency and profitability.

Jan 1, 1980

Since the earliest recorded prospecting of the 1860's mineral exploration and mining in Fiordland has been discouraged by the formidable physical difficulties presented by its isolation, extremely rugged relief, treacherous coastal waters and generally unfavourable weather conditions. Government assistance was often sought by the miners and prospectors but little, if any, support or encouragement was received after the initial period. During the 1840's decorative marble was quarried at Caswell and Dusky Sounds. A prospector discovered and attempted to mine copper sulphides to the north of Dusky Sound (Parks Mineral Beds) and near Mt Solitary. A small Pb, Zn, Cu, Ag, Au bearing quartz reef was discovered and driven on in the granite coast line of Preservation Inlet (Bradshaws Reef) and the ore roasted on site. Alluvial and quartz lode gold was discovered at Preservation Inlet in the 1890's and led to the recorded recovery of 11 000 oz of mainly lode gold. Falloff in grades with depth, thinning and splitting of the reefs and the high mining costs at this location led to a virtual abandonment of the field by 1906. In the late 1950's and early 1960's the geology of Fiordland was mapped by the Geological Survey at 1:250 000 scale, but field work was largely confined to the shore lines of the coast and fiords. In view of the physical difficulties it is not surprising that mineral exploration and mining up to 1970 was limited to the scant attention outlined above.

Jan 1, 1977

By Arndt MB, Bamberg S

The evaluation of risk is becoming more important in the siting of mining operations in the United States as well as the rest of the world. The determination of environmental, economic, as well as health and safety risks is an important step in the planning of any mining operation. Hydrogeology plays an important role in pre-mine planning and in the determination of these risks. The mine operators must determine if ground water would inhibit mining in any way. Factors which are important to consider include mine dewatering economics, slope stability, and other adverse hydrologic impacts. This paper presents methodologies for the characterization of hydrogeological risks for a mining operation. First of all, the term risk analysis is defined and its utility is addressed. Then, stepwise methods for performing a typical risk analysis are presented. Finally, the application of risk analysis to hydrogeology in mining is given. With slight modification, it is believed that these methodologies can be used to evaluate the hydrogeological risks for any mining operation.

Jan 1, 1988

By S G. Gatehouse

Extensive gold mining activity û dominantly alluvial û has taken place in the Sofala-Wattle Flat district since the 1850s.This work will have located most, if not all, of the visible sources for the gold in current stream systems.Also, there are many gold bearing elevated Tertiary alluvial terraces in the district which may confuse possible gold signals from primary hard rock sources in the streams.Associated element signatures eg As and other chalcophiles, will discriminate non-alluvial signatures but will not necessarily distinguish non gold bearing mineralisation.Both trace elements and conventional gold analyses will dominantly re-identify known occurrences. Conventional BCL sampling is considered misleading as experience from the Oberon area to the south of Sofala demonstrated that BCL sampling was very sensitive û perhaps too sensitive.All occurrences û major or minor û of gold will be detected (Gatehouse, 1992). To improve on BCL sampling, a small, -120# sample with selective duplication was recommended to screen coarse-grained gold anomalism and a program of sampling covering an area thought to be prospective was enacted.Samples returning anomalous Au were analysed in duplicate and if the results demonstrated reproducibility, indicating fine gold only, the sample site was assigned a high priority.It was found that most of the reproducible samples clustered in one area û Spring Gully. The results of this sampling program led to immediate identification and, ultimately, the successful delineation of the Spring Gully gold deposit near Wattle Flat.

Jan 1, 2004

By P Dean, M Elmouttie, Y Duan, X Luo

Slope instability is one of the major concerns in open pit mining operations. A significant collapse of the pit wall can result in injuries, damage to machinery and interruptions to production. A broadband microseismic monitoring technique has been developed for diagnosing the healthy condition of a target slope area. This technique has been successfully applied to an open pit mine in Chile. Our research has found that this microseismic monitoring technique can be used in open pits for tracking and locating a falling rock that is rolling on a slope, if a dedicated seismic sensor network has been established. In collaboration with other monitoring techniques (radar, laser scan, aerial photography), more accurate determination of rock rolling trajectories can be obtained. In this paper, an example of using the CSIRO microseismic monitoring technique at an open pit mine is presented. Results from an experiment where we used the microseismic technique for determination of the trajectory of a rockfalling on a slope are also presented.

Nov 8, 2021