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By McBride N

Location The Boddington Gold Mine (BGM) is located approximately 120 km south east of Perth, Western Australia. (Figure 1). Located within the picturesque Darling Ranges, the land was previously used for forestry activities prior to mining commencing in mid-1987. Mineralisation is hosted within deeply weathered felsic and intermediate intrusions and volcanic rocks of the Saddleback Greenstone Belt.

Jan 1, 1995

By Walraven F, Knott G. G

Using a typical small logging instrument (Neltronic KPD), a natural gamma reference section for part of the Brockman Iron Formation and part of the Mt. McRae Shale has been established in the Newman area. This is compared with the stratigraphic type section of Trendall and Blockley (1968). Folding and faulting are recognised using natural gamma logs. Because of the confidence with which stratigraphic horizons can be identified, less expenditure on diamond and percussion drilling is required to confirm stratigraphic position. Using natural gamma logs as stratigraphic control the apparent thinning of the Banded Iron Formation during iron enrichment is Demonstrated.

Jan 1, 1973

The need for ventilation around mine workings derives from the various gases found in mine atmospheres and CH4, the principal diluent is in quantity depending upon several factors. Several of these are seam thickness, depth of cover and working method and the French Regulations typify controls on coal mine ventilation. There are many factors affecting production of CH4, in addition to coal production, such as the geological setting of the working seam, the geometry of workings and the rates of advance. The possibilities of spontaneous combustion should not be overlooked. The complexity of high production modern colliery layouts is such that sometimes there maybe 200 airway branches. There are specific differences in ventilation networks between the mining methods of rooms and pillars, shortwalls and longwalls as affecting resistance losses, as well as necessary airflows and ventilating

Jan 1, 1983

By Revy T

A testwork program aimed to improve the assaying of underground face samples established that for an Accelerated Cyanidation Extraction using the LeachWELLTM 60X catalyst, followed by an Aqua Regia finish (to quantify non-cyanide-extractable gold): ò Assay results (including the aqua regia finish) from a full set of samples from one underground face can be returned within four hours. ò The reagent dose to make the method simple and 'bullet-proof' is 8 gm LeachWELLTM 60X and 20 gm NaCN per 200 gm sample (30 per cent solids). Pulverising is to 90 per cent passing 75 micron (compared to the standard of 90 per cent passing 150 micron), and cyanidation is completed within one hour - however both might be further optimised. ò The LeachWELLTM/Aqua Regia results demonstrate that Fire Assays suffer from a significant nugget effect which makes the Fire Assay data relatively unreliable. ò Original costs, specific to Bannockburn (viz including an Aqua Regia finish), handling approximately 20 000 to 25 000 per annum is estimated to be $5.40, ie about one-third less than fire assaying. Optimising is further reducing these costs. It is estimated that the LeachWELLT"'/Aqua Regia assay procedure has reduced the probable error limits of any given assay of this ore from the range 0.74x to 1.36x for Fire Assay, to an appreciably smaller range of 0.90x to 1.11x. Thus for a cut-off grade of 1.60 g Au/t, samples with Fire Assays ranging up to 2.18 g Au/t have 25 per cent chance of being below cut-off, while samples with Fire Assays as low as 1.18 g Au/t have an equal chance of actually exceeding cut-off grade. This 1 g Au/t range in uncertainty is generally unacceptable for many practicalgrade/tonnage relationships. By contrast, using LeachWELLTM + Aqua Regia assays, the estimated corresponding limits are 1.44 g Au/t and 1.78 g Auk respectively - a far more tolerable 0.34 g Au/t range of uncertainty. Subsequent data has demonstrated that sufficient accuracy for grade control is achieved by Accelerated Cyanidation alone, further halving the cost of assays.

Jan 1, 1994

By Ritchie AS

The principles of chromatographic and electrophoretic separations are described in simple non-mathematical language. Brief details of the analytical procedures and of equipment are given. Partial analyses of rare earth elements in monazites from four localit- ies in New South Wales are compared with analyses from other localities. The presence of uranium in two of the monazites is recorded. The occurrence of rare earths in nature is outlined and its geological significance is indicated, A low capital cost method of analysis of rare earths in monazites is Introduced.

Jan 1, 1972

By Mosusu N

Geothermal anomalies of different types occur within distinct geological/structural settings in Papua New Guinea. According to R.F. Herring, geothermal occurrences in Papua New Guinea can be classified into two types, those related to vulcanism (Lihir, Rabaul and other series of islands along the volcanic arc) and those resulting from a regional heat flow probably caused by radiogenic sources, for instance those in the Wau/Bulolo area. The manifestation of this potential source of energy generally coincides with either converging or diverging tectonic plate boundaries. Previous inventories on thermal waters were carried out by vulcanologists from the Rabaul Observatory in the early 1960s. However, these studies rarely included chemical analyses of water and gas emissions and the investigations were carried out in an ad hoc manner, generally as a secondary activity. The most recent investigation on thermal waters was conducted on Lihir Island in connection with the development of the open pit gold mine. These studies included detailed exploratory drilling to a maximum depth of 730 m, and a water chemistry isotopic sampling and analysis programme. The hydrothermal waters were not considered as an energy source but as a hazard during the development stage of the mine. Nevertheless, the geothermal anomaly observed at Lihir includes hot springs emerging along the coastal zones with temperatures that approach 100¦C, steam, and thermal borehole waters with temperatures that exceed 200¦C. Chemical analysis results of thermal fluids from Rabaul, Talasea and other areas in Papua New Guinea generally show high total dissolved solids and low pH. In contrast, recent results from the deepest and hottest thermal source at Lihir shows a neutral pH, a Na-CI-SO4 composition and temperatures above 200¦C. Despite the concentration of chloride being similar to that of sea water, other chemical results and stable hydrogen and oxygen isotopic compositions of thermal fluids imply the source to be mixture of local meteoric water and deep thermal water rather than sea water. Results of geothermal modelling suggests that the total geothermal uptlow is equivalent to 54 MW.

Jan 1, 1997

By L M. Lobato, J C. S Seoane, F J. Baars

The Carajßs Province presents several volcano-sedimentary sequences that comprise the Itacai·nas Supergroup. The rocks represent bimodal volcanism, and clastic and chemical sedimentation in relatively unstable basins subject to recurrent structural events with subsidence and volcanism. The Grpo Parß Group represents one of these sequences with mafic volcanic rocks that enclose discontinuous jaspilite lenses, with development of large high-grade orebodies (Fe >65 per cent). This unit is named the Carajßs Formation and presents peculiar characteristics compared to other iron districts in the world, thereby departing from the classic Lake Superior or Algoma iron formation types. Owing to the dense vegetation, lack of outcrops and harsh landscape, the structural analysis of the district can only be accomplished by combination of regional field work, detailed structural work on the open pits, and remotely sensed image interpretation, in this case Landsat ETM7, JERS-1 images and the SRTM digital terrane model. The regional trend of the several sequences of the area is approximately N-S and the structure is dominated by a flattened flexural fold system with axes moderately dipping WNW, intersected by several strike-slip faults subparallel to their axial plane. The Serra dos Carajßs represents an s-shaped synform-antiform pair, herein named the Carajßs Fold. This regional structure is partially disrupted by the Carajßs Shear Zone that divides it in the northern (Serra Norte) and the southern (Serra Sul) Ranges and also probably prepared the terrane with the development of pathways for mineralising hydrothermal fluids forming large high-grade massive iron bodies. Syntectonic granitic bodies played an important role in the structural evolution of the area as well. They caused localised ductile flattening deformation and thermal contact metamorphism in surrounding terranes. The Estrela pluton, for instance, was responsible for the discontinuity of the regional trend between the Serras do Rabo and Leste. The Carajßs Province is regionally the upper crustal product of a very shallowly eroded dome-and-keel geometry of Neo-Archaean volcano- sedimentary units intruded by syntectonic calc-alkaline intrusives and overlying pre-existing infracrustal rocks. The lithostructural data suggest continental-margin back-arc basin development and closure in an oblique collision belt, with N-S shallow crustal shortening, parallel to the inferred pre-existing strike of the stratigraphy.

Jan 1, 2005

An integrated computer system (the Short Term Mine Management System) has recently been developed by B.H.P. Steel Long Products Division in Whyalla, South Australia for use in their open pit iron ore mines.The system incorporates blast design, comprehensive blasthole data handling, grade coilrol, stockpile scheduling and management and reconciliation within a single, user friendly computer package. The blast design system allows the blasting engineer to design the layout of holes for a production blast using geological information projected from the bench above to aid in appropriate blasthole positioniog in particular rock types. The grade control system allows mining blocks to be designed and evaluated from blasthole information using interactive graphics processes. The handling, storage and reporting of blasthole survey, assay and geological logging data forms an integral part of this system. Stockpiles can be constructed from a number of mining blocks to reach a specified target grade using the stockpile management system. Although not yet integrated, the reconciliation system will reconcile stockpiles back to mining blocks and to the geological model.

Jan 1, 1990

Lungfish and crayfish inhabit continental ecosystems similar to those of their ancient counterparts in the Permian (lungfish) and Triassic (crayfish) Periods, exhibiting similar burrowing behaviors to live, breed, and escape desiccation. Identification of their burrows in the geologic record when body fossils are absent has relied on the overall gross morphology of the burrows and the process of elimination. A method of burrow identification has been developed by evaluating burrow structures in an attempt to designate architectural and surficial burrow morphologies that uniquely reflect the distinctive burrowing mechanism of a particular organism. The information from this method defines the burrowing signatures of an organism, enabling the differentiation of their burrows even when fossil evidence is lacking.The lungfish constructed simple, vertical burrows with bulbous terminations. The burrow walls exhibit fine, horizontal to sub-horizontal striae and vertical to sub-vertical striae near the top of the bulbous terminus, reflecting a burrowing style similar to modern burrowing lungfish. The crayfish constructed simple, vertical burrows to complex burrows with multiple branching and chamber development. The burrow surface ornamentations exhibit horizontal to sub-horizontal ridges, vertical to sub-vertical groupings of scratches, mud- and lag-liners, knobby and hummocky textures, and body impressions, which reflect the burrowing mechanism of the crayfish.

Jan 1, 1990

By Smith S. F, Terezopoulos N. G

This paper discusses experimental results of physical scale models employed to study the stability of a pillar between rectangular roadways. A programme of laboratory investigations utilising a bi-axial test rig has been undertaken to examine the influence of various stressfields on the stability of pillars between mine roadways. The effect of pillar height/width ratio on the overall stability is studied. Observations of failure characteristics in and around pillars are discussed especially in relation to the various stressfields applied to the models.

Jan 1, 1992

By C McIntosh, M van Dam, N Whetter, R Lane, M McCulloch

Mine geology is understood through synthesising large amounts of structural, lithological, geochemical and geophysical data derived from the original topographic surface, drilling and surfaces exposed and removed during open cut and underground excavations. Computer- generated 3D geological models of any mine environment need to incorporate large amounts of information but also should be regularly updated with typically frequent influxes of new data. Geologists with the local knowledge should also be involved in the model construction, enhancement and interpretation, placing ease-of-use functionality high on modelling software requirements. Implicit-style modelling is a fast-growing area of 3D geological software development where interpolated surfaces such as lithology boundaries and bedding orientations are defined mathematically as functions rather than explicitly through coordinate meshes. The functions are constrained only by the data and not by an artificially imposed grid; therefore, implicit 3D modelling can process a lot of information quickly and routinely operate on original data (such as observed contacts and structural data) rather than on evolved iterations and interpretations. 3D mine geology models can be readily updated with new data, which can be automatically reprocessed to test ideas in near-real time. Implicit, function-based 3D modelling software has been applied to the Globe-Progress mine in West Coast, New Zealand. This structurally- hosted gold mine has some geometrical conundrums that are in part being resolved as excavation of the open pit proceeds. The relationship of the Globe-Progress ore shoots to hanging wall and footwall structure is still not fully understood, however, and 3D geological modelling is assisting with visualisation and testing of structural hypotheses. The modelling is also capable of predicting areas of bedding defect slope failure in yet-to-be excavated parts of the mine.

Jan 1, 2009

The Devonian Mount Morgan gold-copper deposit was situated on the western margin of the Calliope Volcanic Are assemblage, in the northern New England Orogen. Recorded production from commencement of mining in 1882 to mine closure in 1989 stand

Jan 1, 1994

In Situ Bioremediation of a Heavily Polluted Alkaline Soil in a Uranium Deposit

Sep 13, 2010

Jan 1, 2004

By L Cain, C Every, S Mirlatifi, J Ashley

This paper presents a geographic information system (GIS) based method for the prediction of ground movement and the associated impact on existing buildings and structures due to tunnelling in the North West Rail Link (NWRL) project. The NWRL is a priority rail infrastructure project for the New South Wales (NSW) Government and includes 15 km of twin tunnels between Bella Vista and Epping, which will be Australia’s longest rail tunnels. The NWRL tunnels will be constructed in an urban environment where the prediction of ground movements induced by tunnelling and the associated impacts to existing structures must be assessed in the early design stages of the project. An assessment process was developed using GIS able to respond to design changes.An iterative GIS analysis methodology was developed to generate ground settlement contours and identify impacted buildings and structures in response to multiple changes in tunnel alignment during design development stages. The GIS analysis undertook to rapidly provide detailed and accurate parameter information including tunnel depth from surface, tunnel separation, diameter and sample point proximity to the tunnel and assess ground movement contours along the project alignment. Determination of the ground surface settlements were based on empirical methods proposed by Peck (1969) and Mair (1993). The control parameters and the relationship between damage categories and risk classifications for impact assessment were based on Burland, Broms and de Mello (1977), Rankin (1988) and Boscardin and Cording (1989) methods.The GIS-based ground movement impact assessment approach adopted for the NWRL project demonstrates an efficient, iterative and robust approach and could provide an initial framework for other similar tunnelling projects where rapid design changes and early understanding of tunnelling impacts are required to bring greatest benefit to all stakeholders.CITATION:Mirlatifi, S, Cain, L, Ashley, J and Every, C, 2014. An iterative geographic information system based approach for the assessment of tunnelling impact to existing buildings and structures, in Proceedings 15th Australasian Tunnelling Conference 2014 , pp 647–652 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 17, 2014

By F Wu, H Wang, W Chen

A pressurisation method with multiparallel fans has been adopted at HongLiuLin Coalmine to control the significant external air leakage through the goaf area of coalface 15207. Potential damaging effects of large external air leakage on a coalmine’s ventilation system are analysed according to the current air leakage status caused by the exploitation of shallow-covered coal seams. The use of pressure balanced ventilation to prevent external air leakage through goaf areas is introduced. The calculation of ventilation network of HongLiuLin Coalmine shows that the air resistance of an external air leakage branch through a goaf area and the air pressure drops from the intake slope to the working face can be adopted to determine the values of pressure to be increased by regulating fans and airflow controlling parameters of regulators. By investigating airflow requirements of the pressure-balanced area as well as the performances of the auxiliary fans currently used in the coalmine, the number of pressurisation fans needed is fixed. The expected result is achieved after the pressurisation method has been carried out, which can be helpful for other coalmines to handle similar problems.CITATION:Wu, F, Chen, W and Wang, H, 2015. Multiparallel fan method to prevent significant external air leakages through a goaf area of a shallow covered coalmine, in Proceedings The Australian Mine Ventilation Conference, pp 267–270 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By M Sparrow

The Victoria Park Tunnel project is an inner-city alliance project in central Auckland, New Zealand. The existing two-directional viaduct will be modified to single-direction flow, and a new northbound 440 m cut and cover tunnel will be constructed beneath Victoria Park. Three-dimensional (3D) visualisation media were used to communicate key design innovations to stakeholders and the general public. The 3D visual material has proven a useful tool for informing motorists of a new safety barrier method adopted for traffic management.This presentation will explain how 3D visualisation was incorporated in the project and will showcase the 3D visualisation media created for the project.

Mar 8, 2011

By Coppock BW, Scott TC, Firkin GR

The pollution control measures taken on the Imperial Smelting Process (ISP) operated at Cockle Creek are described together with environmental monitoring strategy and the statutory restraints applied in New South Wales. An outline of developments in the gaseous, liquid and noise control areas is given.

Jan 1, 1975

Subsidence issues associated with historic mine workings have highlighted the need for enhanced geotechnical management of the Martha pit over the remaining life. In conjunction with a detailed analysis of pit slope issues a comprehensive geotechnical management plan has been developed at Martha and is being used as the basis for development of similar plans in other Newmont operations.   This paper covers the geotechnical issues facing the Martha operation and the development and application of the management plan.

Jan 1, 2004

By Lynch AJ

Comminution within rod mills has been investigated by izse of a matrix analysis of breakage processes. A para,~ meter, the number of breakage stages, has been introduced and cornfninut-ion within all rod mills has been expressed in terms of the¦1-number of breakage stages- and a function which des--cribes' the feed rate, mill diameter and mill speed.'The effect of variation in feed rate, feed sizing analysis and mill speed on the number of breakage stages-is-,-discussed.

Jan 1, 1963