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By Allchurch P. D

At Perseverance a reserve of 45 million tonnes at 2% Ni was indicated by drilling. Holes were drilled in trellis pattern on section lines 61m apart to assess shallow mineralization. To explore at depth holes were spaced 122m apart, collared vertically, then allowed to deflect under controlled drilling conditions. The mineralization may be divided into the three homogeneous classes of soarsely disseminated, heavily dissem- inated and massive sulphides. In the standardised sampling and assaying procedures used to assess the deposit, attention was always paid to these fundamental ore types. All sampling and assaying processes were continuously monitored by checks. Sampling and sample preparation errors were small, to judge from the differences between results of original and check samples. Assaying errors, determined from analyses made by independent laboratories using different methods, slightly exceeded sampling errors. Comparison of underground core, c'iannel, and grab sampling, suggests that core sampling tends to undervalue.

Jan 1, 1976

By De Carvalho J

The average installed refrigeration capacity on South African gold mines has increased by about eighteen per cent annually for the past 15 years; both the number of installations and their duties have increased. One consequence of these large refrigeration installations is that careful attention must be paid to the system for distributing cold water. In these distribution systems, devices which minimize the temperature rise of the water delivered to the underground workings and which also reduce the pumping requirements for returning the water back to surface are used. In this paper the suitability of these various devices are examined and with the aid of a specially developed computer program their optimum operating conditions are determined. In addition the optimum combination of surface and underground refrigeration plants is examined for a hypothetical mine at various depths and the importance of pump efficiency on total distribution costs is discussed.

Jan 1, 1988

By Olson H, Kincaid R

The marine portion of the Pacific Basin and Rim constitutes a significant part of the world's surface in which the mineral resources are virtually undeveloped. Indications of substantial resources have resulted in speculation and uncertainty with regard to their potential in the near term. The main issues are centered on the markets for the resource materials, the technology needs for their recovery, and the possible impacts of their development on the environment. While the governments of Japan, France, the Soviet Union, India, China, and Korea are financing new programs in deep ocean mining, the US is consolidating its early leadership by the continuation of NOAA's authority under the Deep Seabed Hard Mineral Resources Act and the Sea Grant Act, Interior's authority under the outer Continental Shelf Lands Act, and by the development of a new Marine Minerals Technology Center within the Department of Interior's mineral institutes program, managed by the U.S. Bureau of Mines. The Center has a Continental Shelf Division (CSD) located in Mississippi, and an Oceans Basin Division (OBD) located in Hawaii. Research and training in the divisions is directed toward the practical aspects of mineral recovery from the nearshore and deep ocean environments with a strong bias for the OBD toward industrial and international cooperative programs in the Pacific Basin and Rim. In terms of resource development, the marine minerals in the Pacific Basin may be favored in some cases, in competition with land sources, by political and environmental considerations.

Jan 1, 1990

THE power requirements of the Mount Lyell Mining and Railway Company at Queenstown, Tasmania, have, since the inception of smelting operations in June, 1,,896, been derived continuously from the extensive forests in the watershed of the Queen River, adjacent to -the works, the firewood being of good quality, mainly composed of myrtle or beech (Fagus Ounninghami), eucalypts, and manuka (Leptospermum ericoides).The country is very rugged and mountainous, indented by numerous ravines and gullies, and intersected by many creeks, which are subject to periodical floods, under the influence of a heavy and persistent rainfall. The areas so far exploited aggregate a total of about 42 sq. 'miles, and this denuded country gives promise of ultimately becoming very valuable pastoral ground for cattle-raising. The tonnage of wood yielded per acre varies from 40 to 100 tons on stack measurement of 80 cub. ft. per ton, 60 tons per acre being considered a good average yield. The gross amount of firewood handled during the past 13 years approximates 1,200,000 tons, the greater portion of which has been obtained by ordinary tramming methods. The company's main line of railway, 3-ft. 6-in. gauge, has served as a trunk line for all supplies derived from the Queen River valley, south of the reduction works, while the northern and western areas have been exploited by means of...

Jan 1, 1911

HIGHWALL MINING - DECISION TO MINEUlan had completed operations in the first Open Cut area due to high stripping ratios and the presence of geological features which destroyed a significant portion of the coal in the upper part of the seam. The pit had been abandoned in 1994 and operations had moved to a new location to the north west.

Jan 1, 1998

Kamhalda is located within the Yilgarn Craton of Western Australia, specifically in the Norseman - Wiluna greenstone belt. Numerous nickel sulphide deposits have been mined at Kambalda with I I mines currently operating. For several years, a program of in-mine geophysics has been operating at Kambalda, with downhole electromagnetics (UHEM) one of the key techniques used. Three case studies illustrating the uses of UHEM in mines are presented here. In the first example, the Helmut South deposit was discovered as the result of an extensional exploration program. The first drill hole in the program intersected ore width and grade mineralisation at around 760 in depth. Two subsequent holes intersected subgrade mineralisation. DHEM surveys were completed in each of these three holes, with anomalies recorded indicating that a large conductor was located directly south of the first hole. The next hole intersected this target, for an intersection of 21.6 in at 3.5 per cent Ni. DHEM continued to play a role as the exploration program proceeded, providing drill hole targeting based on anomalous responses recorded in each drill hole. In the second example from Carnilya Hill, old drill holes were surveyed with DHEM in order to search a large section of prospective contact for massive ore pods. An off-hole anomaly was detected and subsequent mining discovered a small but high-grade pod of ore which was extracted for a considerable profit. Carnilya Hill has limited reserves and discoveries such as this, assist in keeping the mine operating. In the third example from Victor, a program of drilling intersected thin ore profiles in an interpreted flanking position. Without massive ore close by, these intersections probably do not constitute economic mineralisation. DHEM surveys of three holes did not detect any conductors. The area is now regarded as sterilised of significant massive ore and exploration efforts and dollars can be focused in other areas. These three examples demonstrate the type of successes that can he achieved through the use of DHEM.

Jan 1, 1997

By Lyman G. J, Ka

The use of images to determine blast fragmentation is the only feasible technique when one does not want to disturb the production cycle. However, three major problems exist with the use of images. The first is determining real size from a two-dimensional particle, the second is estimating the fines which are missing due to image resolution and particle size range, and the third is proper sampling such that a statistical probability can be calculated for the distribution. Once these problems are resolved, the tedious process of digitizing images by hand may be automated. This paper describes the present techniques used at the JKMRC to "size" blast fragmentation, estimate the missing fines using the Rosin-Rammler equation, determine the sampling error using Gy's sampling equations, and extract the particles from an image using an IBM-AT computer.

Jan 1, 1990

By W G. Rowley

The Fortescue Metals Group story began in 2003 with a vision to establish an infrastructure project that would connect the stranded iron ore deposits of the Pilbara region of Western Australia with the steel mills of Asia. Following exploration successes in the Chichester Ranges using their new exploration model, Fortescue established significant iron ore resources at Cloudbreak and Christmas Creek during 2004 and 2005. By May 2006 the definitive feasibility study for mine, rail and port was completed, many of the key government approvals had been obtained, product development and market acceptance were complete and 1.07 Bt of total proved plus probable iron ore reserves were defined to support a 20 year mine life from the Cloudbreak and Christmas Creek deposits. Project construction commenced in September 2006 following a successful $3.2 billion capital raising. By April 2008, the mine and processing plant at Cloudbreak were completed along with the Herb Elliott port facility at Port Hedland and 256 km of heavy haul railroad linking the mine with the port. Mining of overburden commenced at Cloudbreak in late 2007 and by 15 May 2008 the first shipment of iron ore had departed for China. In the first 12 months of operation total shipments amounted to 24.6 M wet metric tonnes with weighted mean composition of 58.9 per cent Fe (64.4 per cent Fe calcined), 4.3 per cent SiO2, 2.0 per cent Al2O3 and 0.047 per cent P. Exactly 3.5 years between the Cloudbreak discovery hole and commercial production. The project success depended on many technical breakthroughs including a new exploration model, application of the surface miner as the main mining production unit, design of a new marketable fines product called æRocket FinesÆ, a highly efficient ædesandÆ flow sheet for upgrading of 2.4 per cent alumina run-of-mine to 1.9 per cent alumina Rocket Fines, 40 t axle loads for the heavy haul railway and a high capacity-highly automated port facility.

Jan 1, 2009

By Jepsen L, Gifford M, Thomas G. S

Mine planning requires careful prediction of both the head grade and tonnage of mineralisation. As part of the planning process, operators of the Murrin Murrin nickel/cobalt orebodies (located in the Eastern Goldfields province of the Yilgarn

Jan 1, 1998

By McOnie A. W, Rutherford PG

A volcanic sequence is described from the Golden Cross Mine, Waihi, New Zealand. The sequence includes seven lithostratigraphic units comprising flow and pyroclastic units of Coromandel Group andesite and dacite and overlying Whitianga Group dacite and rhyolite which is intruded by the Golden Cross dacite porphyry and rhyolite dykes. The sequence is mineralized and is unconformably overlain bv_ two post-mineral units, the lacustnne Waitekauri beds and Omahine Subgroup andesite. Detailed structural analysis of mine data has identified four deformational events (D 1-D4) and related these to the gold-silver mineralizing events. Faulting was coeval with the mineralization and directly controlled the development, localization, style and geometry of the ore shoots. Mineralization developed in competent lithologies where dilation occurred during faulting. The Empire Fault is the master shear which controlled fluid flow. Mineralized veining developed in response to tectonic pulses occurring at slightly different stages as represented by the underground Empire vein complex and the open pit vein array. The mineralizing events culminated with the deposition of barren calcite veins. Post-mineral movement along the Western Boundary fault appears to have offset the ore body.

Jan 1, 1995

By Fazakerley VW

The Murrin Murrin deposit is located about 210 km NNE of Kalgoorlie and 50 km E of Leonora in the North Eastern Goldfields region of Western Australia at latitude 28¦ 50'S. longitude 121¦ 54'E on the Laverton (SH 51-2) 1:250 000 map sheet. The tenements are held by Anaconda Nickel NL. Geological investigations between 1994 and 1996 resulted in resource calculations being completed for the ten lateritic nickel cobalt deposits shown in Figure 1. At a 0.8 per cent nickel cut-off the resources at May 1996 for the nine deposits are 116.8 Mt at 1.10 per cent nickel and 0.082 per cent cobalt. The nickel-cobalt mineralisation is contained in a laterite profile developed over Archaean serpentinised peridotites. A bankable feasibility study has been completed and the project is scheduled to be in production by the beginning of 1998.

Jan 1, 1996

By Mance G

Today there are many different techniques of soil remediation used in Australia and throughout the world. This paper considers the thermal desorption remediation technique and, in particular, the application of high temperature filtration to the process. The thermal desorption technique involves the treatment of hydrocarbon (oil, petrol, etc) contaminated soil. The process involves heating the soil in a retort or kiln to drive off the volatile organic contaminants. The exit gas stream from the retort is subsequently passed through an after burner to thermally oxidise the hydrocarbons. This technique produces soil and combustion gas streams which are free of hydrocarbons. Due to the heating and agitation of the soil within the retort, soil particles become entrained in the hot gas stream. To avoid the blockage and fouling of the system's interim ductwork and the afterburner, high temperature filtration technology has been applied to remove these soil particulates without cooling the gas Stream.

Jan 1, 1995

In comparisons of a trial extruded brick containing 33 per cent coalwash and 67 per cent clay and a trial pressed brick containing 100 per cent coalwash with a standard extruded clay face brick, the mixed feed stock trial brick compared favourably with the standard brick. If a highly plastic clay is used to mix with the coalwash, satisfactory results are obtained in respect to dimension, strength, water absorption, efflorescence, resistance to salt attack, hardness, colour, weathering, mineralogy and porosity. Although a brick containing only coalwash can be successfully manufactured in a press, its mechanical and physical properties are inferior. This mixed feed stock brickmaking technology leads to the utilisation of a by-product with a potential saving of raw material costs. The extent of use is likely to depend on the proximity of the coal washery and the brickworks and the economicsof transportation costs.

Jan 1, 1992

The Quioma Mine is located along the axis of the Cordillera Oriental, 130 km southeast of Cochabamba, South Central Bolivia. Silver, lead, zinc, antimony, and gold have been intermittently produced from veins in the Quioma area since Colonial times. Mineralization occurs within steeply dipping fissure veins transecting moderately folded Lower Ordovician sediments. Tectonic activity is early to mid-Tertiary and the vein system parallels the fold axis of a major northwest-southeast striking, doubly plunging anticline. Vein sets occur within a 2 km wide band over a strike distance of 13 km along the northeast limb of the anticline. Economic mineralization occupies syntectonic pre-mineral fault zones developed in more competent stratigraphis units of Lower Ordovician clastic sediments. Veins average 55 cm in width, although mineralized structures up to 3 m wide with a known strike length of several hundred meters have been mined. Mineralization consists of siderite, argentifferous galena, sphalerite, and quartz, with minor amounts of chalcopyrite, barite, and bournonite. Pyrite is rare except at the Boston vein where it occurs with stibnite that contains trace amounts of gold. A marked characteristic of veins in the district is evidence of repeated stages of movement during mineralization. Intrusive rocks are rare in the Quioma area. Narrow porphyritic dikes of Andesitic composition averaging 1 m in thickness have been observed. These dikes occasionally show a close spatial relationship to the veins and are often kaolinized and carbonitized. Vein and dike contacts are sharp and alteration does not appear to extend into the wall rock. Mineral zoning is suggested by antimony mineralization observed in peripheral areas of the anticline.

Jan 1, 1987

By Patridge A. C

Hydrocyclones have widespread use as classifiers in applications such as mine fill preparation and coal preparation. A fundamental conflict often exists between recovery of all of the valuable material and maintaining the quality of the product. This conflict is a result of a portion of the feed material passing through the cyclone, effectively without undergoing any classification. This paper describes an investigation, undertaken as an undergraduate project in mining engineering at the University of NSW (Brook, 1994), into aspects of cyclones in which supplementary water injection is used in an attempt to reduce the amount of misplaced fine material reporting to the coarse product and hence improve the overall classification efficiency. In particular, the study concentrated on the effects of different modes of water injection. Two methods of introducing wash water into the cyclone body were investigated. A series of tests were performed on a laboratory hydrocyclone having provision for radial water injection at different levels through small orifices in the wall of the conical section, and a preliminary study was made of the performance of a novel cyclone in which the conical section had walls of a permeable polyethylene, permitting a uniform introduction of wash water over the entire surface.

Jan 1, 1995

By Watsford R. M S, Hutton R

Following the delineation of significant extra ore reserves during 1990, the decision was made to expand production from 350,000 tonnes of run of mine ore per year to initially 600,000 tonnes increasing to 750,000 tonnes per year. The existing plant consists of a conventional three stage crushing plant followed by a heavy medium separation plant that produces a product prior to grinding. Grinding is conducted in three stages of ball mill in series. Alternatives examined for expanding production included: aò SAG mill - ball mill circuit replacing the secondary and tertiary stages of crushing, the heavy medium plant and the existing ball mills; and, upgrading of the existing circuit configuration.

Jan 1, 1991

Bendigo is AustraliaÆs second-most productive goldfield, having produced some 22 million ounces of gold between 1851 and 1954. Bendigo Mining Limited (BML), the sole lease-holder of the Bendigo Goldfield, is developing a mine that is planned to produce ore from beneath the historical workings for at least the next 25 years. The high-grade Bendigo reefs occur in the proximity of the chevron anticlines, which characterise the goldfield. Typically the reefs display relatively small cross-sectional areas and large (subhorizontal) strike dimensions. They occur in clusters due to interrelated structural controls. Most of the gold occurs as visible grains and laminae, and as such grade estimation is not amenable to ænormalÆ sampling and estimation techniques. The initial phases of exploration and development of the mine focused on understanding and resolving these sampling and estimation issues. In 2005, BML reviewed and updated the March 2004 Feasibility Study, refining the life of mine development strategy. The strategy fundamentally aims to exploit the 11 million ounce Inferred Resource and additional exploration potential by developing the current Kangaroo Flat Mine to produce ore at an initial rate of 450 000 t/yr in 2006/07, expanding to 600 000 t/yr by 2009/10; and developing the Eaglehawk Mine to produce 1 Mt/yr by 2011/12. Ore will be processed initially at the Kangaroo Flat site, and from 2011/12 also at the Eaglehawk Mine 1 Mt/yr processing plant. The two mines will connect underground in 2009. Total ore treatment capacity will be 1.6 Mt/yr, producing 600 000 oz/yr from a head grade of 12.7 g/t gold. The project is planned to operate for 25 years, processing 33.6 Mt of ore producing 13.7 Moz of gold. To achieve this production rate, the exploration and ore delineation programs will require up to 16 diamond drill rigs producing over 200 km of core per year. At the same time, approximately 8 km of on-reef development must be monitored and typically 18 stopes managed concurrently. The processing plants will be located in geographically constrained areas, which will limit the ability for selective stockpiling and campaign treatment.

Jan 1, 2006

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

Reservoir Engineering has developed into an art. One phase of this art is forecasting the futi. perf ormance of oil and gas reservoirs for property valuations. A discussion of the necessity for oil property valuation isgiven. A brief 'discussion of the four most common methods is included and the engineering method is explained in more detail. As an example of oil property valuations, a producing oil lease in Shackelford County, Texas, USA is evaluated.' The recommendations and conclusions arrived at frun the results obtained are presented.

Jan 1, 1962

By Montagnon P, Dagois G

The use of activated carbon for gold recovery has been known for years, but came industrially on stream since the years seventies.Despite several years of experience, the criteria for selecting a carbon have not been clearly determined so far.This paper will try to highlight the user through his experience, on the most important factors which should affect his decision.We will develop:- Physical characteristics - Adsorption characteristicsand try to show that slight variations on these characteristics may have important consequences on the plant design and profitability.

Jan 1, 1984