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The district specially referred to in this paper comprises the very gently sloping country extending from the western shores of Port Phillip from the mouth of the Yarra to Footscray along the Bacchus Marsh railway to near that town thence in a southerly direction to the Little River, and along that river to the coast, 1 as may be seen on the accompanying map. Almost the whole of this area is covered by volcanic rocks, consisting of pumerous sheets of basalt, which have been poured out of various volcanic hills in the districts, such as Mts. Atkinson and Cotteril, near Melton; Mt. Maryand Bald Hill, 12 and 16 miles respectively N.W. of Werribee; and vents in different parts of the parishes of Tarneit, Mouyong, Mooradoranook, Pyweitjorrk, and Derrimut. These volcanoes were in an active state of eruption during a late period of the earth's historyprobably the late Pliocenll, or still younger Pleistocene.Occupying a narrow strip of country, for most of the distance along the coast from Williamstown to past the mouth of the Little River, there occur deposits of still younger age, belonging to the Recent period. These lie on the basalt, and extend for distances varying from a few chains to more than a mile back from the beach. They comprise superficial deposits of blown sand, and raised beaches, composed of marine sands...

Jan 1, 1902

Peculiarities of Quartz Distribution in Zinc Flotation Products and their Influence to Mineral Processing

Sep 13, 2010

Shaft sinking through an amphibolite-granite rock mass experienced rock bursts on the shaft walls and benches. However, rock burst phenomena was exhibited only in granite, which is e1asto-brittle with ability to store strain energy caused by orogenic and man made stresses. To improve ground conditions, blasting of destressing holes at shaft corners was carried out. By this technique rock burst during shaft sinking was minimized, but not eliminated.

Jan 1, 1982

Australia is the world's leading producer and exporter of mineral sands. Despite increased production from some other countries in recent years, Australia maintained its No.1 position in 1988 among world producers of mineral sands concentrates. Production of the titanium minerals -- ruffle, ilmenite and leucoxene, as well as synthetic ruffle -- by the seven companies currently comprising the Australian industry increased in 1988 in response to continuing strong demand for feedstock by the pigment industry. Production of co-product zircon remained at the 1987 level, reflecting declining zircon grades. Exports of mineral sands concentrates increased in 1988; export earnings exceeded $300million. Prices for mineral sands concentrates are now at a historical high and, assuming that the world economy remains strong, real prices should continue to trend upwards in the short term. Exploration in the Eneabba-Cooljarloo region and the Scott River area, both in WA, the Murray Basin, Vic, and the central Queensland coast area, has identified substantial resources of heavy mineral sands. These discoveries have reversed the trend of the early 1980s of falling resources of mineral sands. In 1988, BMR estimated that economic demonstrated resources (EDR) of ilmenite, rutile, zircon and monazite combined was about 72.8 million tonnes. However, a substantial portion of the resources on the east coast are frozen as a result of environmental considerations. The proportion of mineral sands concentrates processed in Australia increased with the commissioning of two new synthetic rutile plants; Australia is now the world's leading producer of synthetic rutile (total capacity 272000 tonnes), most of it for export. Australia's two TiO2 pigment producers have both increased capacity, lifting national capacity by some 70p ercent to over 120000 tonnes/yr. As part of the expansion one producer converted from the sulphate to the chloride process. Other new pigment plants are being proposed for the future.

Jan 1, 1989

By Hargraves A. J

With increasing depth, stresses and stress phenomena are becoming more important considerations in Australian coal mining.A large number of compressive and tensile strength tests was made on coal and rock cubes cut from samples taken in various Australian collieries. In addition, an empirical impact strength test was carriedout on fragments of the same samples, to obtain a correlation with compressive strength.In one colliery, flat-jack measurements were taken to assess stresses in coal ribs and in the roof.INTRODUCTIONBy world standards, some of the New South Wales collieries are approaching depths of cover considered a maximum for bord and pillar the normal Australian coal mining method. Several South Coast collieries are winning coal at depths of about 1500 ft., and future operations are being planned at deeper cover. Some areas of these deep workings produce considerable quantities of seam gas.Phenomena associated with high stress and copious gas under pressure in the seam violent phenoma presenting a danger and a nuisance in mine working - have occasionally occurred, and the phenomena are being investigated as a whole (Hargraves, 1958), and separately as a gas problem (Bolt and Innes, 1959; Hargraves, 1962) and as a stress problem. This paper relates to the latter - to investigations into the strengths of coals and coal measure rocks, and into the stresses in and about coal seams...

Jan 1, 1962

This paper reviews the current techniques employed in the prediction of subsidence and how they have been applied to partial extraction systems. The method using influence functions to describe the shape of the profile is investigated in detail and has been adopted to model the subsidence over workings in Huntly. It is compared with the profile methods developed in the United Kingdom and found to predict the subsidence profile more accurately than these methods.

Jan 1, 1991

By A T. Job, P R. McAree

There is significant value at stake in the mining industry from the implementation of new technologies that support the enhanced profitability and sustainability of mines. However, in order to realise this value, new technology must be implemented in a way that is both effective and sustainable. The industry has a mixed history for technology implementation that provides fertile ground for understanding what is necessary for innovation to deliver value. This paper describes early stage research investigating why this is so, with the aim of improving how to deliver value. Several case studies are provided covering both successful and unsuccessful technology interventions. The paper identifies the common factors that emerge from the case studies, and offers a path forward for further research in this area.CITATION:Job, A T and McAree, P R, 2017. Three case studies on the implementation of new technology in the mining industry, in Proceedings Iron Ore 2017, pp 407–414 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

Common brattice cloths in use in Australian coal mines are compared by permeability measurements. The respective advantages of twill weave and tarpauling* weave cloths are listed, and the improvements to be obtained in the ventilation of a mine by using tarpauling cloths instead of the commonly used twill cloths are stressed. Plastic cloths are widely used overseas and are briefly discussed.INTRODUCTIONThe onset of extensive full-scale mechanization in Australian coal mines during the past few years has increased attention given to the ventilation of working places. Many inadequacies of the present system have been brought to light and not the least of these is connected with the use of brattice cloth, both in directing the flow of air around the face and in acting as a temporary sealing mechanism. A well-constructed line of brattice will only provide fair ventilation for a distance of 100 ft. Beyond this point the volume or air reaching the face falls off rapidly.Some of the shortcomings associated' with the use of brattice cloths are:1. Hurried installation, necessitated by a rapid advance, often results in poor workmanship with, consequently, an excessively high leakage rate.2. High places caused by falls of roof are difficult and time-consuming to seal.3. Curtains, in lines of brattice crossing transport routes, are difficult to maintain.4. Lines of brattice interfere with rock-dusting and clean-up of fine coal.5. Repair and maintenance of brattice consumes much...

Jan 1, 1959

THE treatment by chlorination of the Mount Morgan Gold Mining Company's ores was first accomplished, early in 1886, by a works having a capacity of 25,000 tons per annum. Shortly afterwards another works was established, capable of dealing with 50,000 tons per annum. The extraction of gold was originally successful and satisfactory, but running expenses were high, averaging £2 19s. 6d. per ton of ore treated. These works were believed to be the largest chlorination pJants in the world at that time. As might have been expected, the mechanical details and chemical process had not been perfected, and, moreover, both works were hurriedly built, and operating expenses were not then considered of such prime importance, as the ore at that time was of very high grade the large quantities of low grade ore since dealt with not being then considered, since the bulk of it was not even known to be in existence.These two works consisted of lock-breakers, high speed rolls, screens, elevators, &c., for crushing; a large number of small handrabbled reverberatory furnaces for roasting; one-ton chlorination barrels and three-ton leaching vats for chlorination.

Jan 1, 1910

By S C. Labram, A Stabile

"Modern train load out stations are becoming faster and have the ability to load a 100 wagon train in less than three hours. At 70 metric tonnes per wagon, that is an average fill rate of 2333 t/h and considering the train is continuously moving, the instantaneous feed rate into the wagon is in the region of 4200 t/h.The main feed conveyor that maintains the level in the surge hopper, above the final weigh hopper, operates in excess of 5000 t/h to ensure uninterrupted charging of the weigh hopper to not disrupt the train loading operation.To avoid demurrage costs (a charge by the Rail Operating Company for exceeding the contractually agreed loading time) the train has to be handled speedily and efficiently and spend the absolute minimum time at the loading facility. Everything else has a much lower priority, including sampling.Thermo Fisher Scientific’s brief was an engineering, procurement and construction management (EPCM) contract to provide a sampling scheme adjacent to the prepurchased and predesigned load-out facility, but which interfaced seamlessly with the loading system of the trains and provided the following: an instantaneous particle size distribution (PSD) result for each truck loaded, and a final PSD for the total train prior to the train leaving the loading facility a crushed (-3 mm) composite sample for chemical analysis for the whole train a composite physical analysis sample for the whole train.The design presented some interesting challenges to our team, but the end result is a system that not only ‘stands alone’ but interfaces seamlessly with the loading system. This paper discusses the design itself and potential improvements to future systems.CITATION:Labram, S C and Stabile, A, 2017. An automatic sampling methodology to determine contractual particle size distribution in rapid train load out stations, in Proceedings Eighth World Conference on Sampling and Blending, pp 229–234 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

May 9, 2017

By D J. Black

Ventilation modelling is used to evaluate ventilation system performance. This paper describes modelling to assess potential changes to a single entry longwall ventilation circuit to improve ventilation and gas management. The longwall panel is extracting a 215 metre face in a 1.5 metre coal seam at a depth of 900 to 1000 metres below surface. The 1.5 metre B seam is located approximately 25 metres below the main 3.0 metre A seam and the gas content of both coal seams is approximately 20 to 25 m3/t. The B seam is extracted prior to the A seam and the mine relies on fracturing of the overlying strata to induce gas emission from the A seam to reduce the gas content prior to mining. Longwall operations in the B seam are constrained by limited ventilation and high gas emissions. Due in part to statutory limits on gas concentration and air velocity, the average longwall production rate is approximately 700 t per day.Gate roads in the B seam are single entry, developed using road headers and supported with steel arches. Additional timber cog support is installed to reduce roadway closure from abutment loading. Due to the slow advance of gate road development, mine management were reluctant to consider significant mine design changes, such as two heading gate roads; therefore, the investigation focused on determining the extent to which ventilation and gas emission impacted on longwall production performance, while recommending short-term, low-cost actions to improve ventilation and gas management to support increased longwall production.CITATION:Black, D J, 2017. Application of modelling to improve ventilation and gas management in a single-entry longwall panel, in Proceedings Australian Mine Vent Conference 2017, pp 239–244 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

A subsurface study of the Maria Lode and associated hydrothermal alteration of andesites within the Karangahake epithermal gold-silver deposit defined the local evolutionary sequence in the once active geothermal system.   Some implications for mining of epithermal deposits arise as a result.

Jan 1, 1984

By W Farnworth

The Huntly West Mine has undergone significant changes in the last two years, which will affect the remainder of the mine's life. The paper describes the evolvement of plans and an overview of the technical considerations made in planning for and implementing the first New Zealand longwall operation. The technical investigations involve the longwall equipment, exploration, ventilation and strata control. The focus on these areas was to ensure that unacceptable project risks were addressed. Implementation of longwall mining at West Mine is planned in three phases, Development, Panel One extraction trial, and Full Longwall operation.   At present the development phase is complete, longwall installation is in progress and production start-up is planned for the end of August, 1991.

Jan 1, 1991

By Gupta R. C

Syria has about 500 million ton deposit of minerals having 34 per cent iron content with alumina and silica as major impurities. Efforts were made to see the feasibility of concentration by four different methods involving washing, high intensity magnetic separation, reduction roasting and magnetic separation and acid leaching technique. It was observed that the reduction roasting with magnetic separation yields a concentrate with high iron (62.3 per cent) content without requiring water which is a scarce raw material in the region. The paper concludes that the detailed study may be made following this route to optimise the process Parameters.

Jan 1, 1999

The Greymouth Coal Project is a proposal to mine by the application of proven hydraulic, and room and pillar underground mining methods; and to process the equivalent of an average of 1.7 million tonnes per year over a forty-year period. The proposed mine site is located ten kilometres north of Greymouth, on the west coast of the South Island of New Zealand. Of the three separate mineable seam groups, the thick Main Seam Group, which makes up 77% of the total resource, will be mined by hydraulic mining technology.   It is proposed to market and produce a high volatile bituminous type coal with low ash (6%) and sulphur (0.4%). Because the inherent ash content is low, the requirement for coal treatment will only be the use of a single cell jig circuit to control the effects of rock dilution and partings. The resulting coal product is tentatively planned to be transported by rail to the port at Lyttelton for loading on to Panamax or Post Panamax size vessels.

Jan 1, 1997

By Bain J. H

Since zinc was first deposited at Risdon in February, 1917, provision of the most economical cathode assembly has been a subject of extensive research, the major problems being corrosion and efficient use of power.From the corrosion viewpoint, a perfect cathode is one in which the life of the headbar and the deposition sheet are the same. However, corrosion usually concentrates in a narrow zone across the face- of the sheet, resulting in breakages which, before the advent of argon arc welding, meant a loss of a 'complete assembly.Attempts to extend sheet life included use of thicker sheets, multitudinous protective coatings applied with varying degrees of success, re-rolling, and for a time, aluminium consumption was reduced when broken sheets found re-use as protecting strips. This latter economy became impracticable when electrode spacing was reduced for greater efficiency in power utilization.As an integral part of the electrode, the headbar was modified accordingly. Copper headbars, although more corrosion resistant, were replaced by aluminium due to a possibility of dissolved, copper promoting deterioration.Thicker electrodes and regulated spacing reduced internal shorting, whilst provision of knife-edge type supports on both contact and insulator ends of headbars aided in electrode centralising and continuous electrical conduction.After much experimeIitation, an assembly has been evolved which, with the aid of argon arc welding and tbe use of minimum additional aluminium, permits comparable headbar and sheet lives, combined with good electrical conduction throughout the life of the cathode.INTRODUCTION Over 300 tons of zinc are produced daily at Risdon from a purified zinc sulphate solution by electrolysis, the zinc being deposited upon all-aluminium (except for copper contact) cathodes. It is stripped in 72-hour cycles from the cathodes, melted and cast into the customary rectangular slabs.

Jan 1, 1958

By T N. Little

The author contends that geoscience is presently under-utilised in the rock fragmentation by blasting process. Before we can set standards in this area, the following is required: mine geologists need to gain a better understanding of the blasting process and the blasting team needs to obtain a better appreciation of geology. Both groups need to be informed of what can be done to improve blasting outcomes, why it is necessary and how it can be achieved. By working closely together, both the geoscience toolkits and blasting expertise can be applied and focused on priority blast sensitive issues, with potential to improve mine economics and safety. Finally, and ideally, mine geologists need to take a leadership role in raw rock mass data collection and data management, and invited to take an active role in rock mass related behaviour data collection, integration and presentation.This paper attempts to provide insight into all these prerequisites for setting a new standard for collaboration and mutual learning in this strategic opportunity area. The potential for blasting to leverage downstream processes is highlighted. Blasting objectives and blast design principles are introduced along with the required rock mass related inputs. Some hazardous geological materials and environmental conditions are described, along with how they can affect operational complexity.Four case examples are used to illustrate the need for closer liaison between geology and blasting professionals. The first related to grade control blasting, aims to demonstrate how a blasting geology approach can add significant value. Case example two demonstrates how geological models and bench face analysis can assist with fragment control. The third and fourth case examples involve an overview of two case studies where timely geological and geotechnical knowledge input and intervention into blasting activities may have reduced losses due to blast initiated open pit slope collapses.CITATION:Little, T N, 2017. Geoscience input into blasting operations – let’s set a new standard, in Proceedings Tenth International Mining Geology Conference 2017, pp 375–384 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 20, 2017

By B Mead, N D. Pascoe

The Grasberg block cave rail haulage system will be located in the Grasberg mining district on the island of Papua, Indonesia at an elevation of almost 3000 m above sea level. It will transport 160 000 t of ore per day from multiple chute galleries to the underground crushing systems. The design entails approximately 23 km of rail (ballasted and embedded track), over 120 ore chutes to deliver ore to the muck cars and three unloading stations to deliver ore to the crushers. The rail haulage system is a closed-loop system entirely within the underground mining complex.The GBC rail haulage project will be a substantial operation. Trains consist of 11–12 bottom-dump 20 m3 muck cars driven by a 40 t electric locomotive, about 400 t per trainload. Approximately 12 trains and one spare are required to maintain full production at 160 000 t/d. All rail installations will be 1435 mm (standard) gauge with AS60 steel.The rail system is designed to operate in full automated mode, including chute loading, hauling and dumping. The operation will be controlled from a surface control room.The rail haulage project has been divided into five stages, which will be brought online over the course of ten years. Current development and construction are focused on Stage 1 for initial production that will occur beginning in late 2017. This stage includes 24 chutes in three chute galleries, one unloading station, workshop areas and almost 7 km of track (3 km of embedded and 4 km of ballast).This paper describes the key components of the rail haulage system and reports on the current status of development and construction of the system. This paper also overviews the challenges, successes, issues and risks of this project in areas such as scheduling, development, construction and operation.CITATION:Pascoe, N D, Mead, B and Vega, H, 2016. Grasberg block cave haulage project – design and construction update, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 585–598 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

Knowledge of true block grades is obtained from a mathematical model of an orebody, simulated with sample grades normally distributed and spatially correlated according io a spherical semi-variogram model.The superiority of kriging to the polygonal method of estimation is demonstrated on this modelled deposit by comparing the true values with the kriged and polygonal estimates obtained from sampling the deposit. Finally, selection of blocks of the deposit on the basis of the estimated values, shows that if kriging is used, what is predicted is largely mined, whilst if the polygonal method is used large biases can occur depending on the position of the cut-off grade.

Jan 1, 1978

By R Blair

The Domain and Burnley Tunnels, which are major features of the Melbourne City Link Project, are MelbourneÆs first road tunnels. They are 1.6 km and 3.5 km in length respectively and are being constructed through a variety of ground conditions. Deeper sections of the tunnels have been driven through the Silurian mudstone which underlies Melbourne. Other shallower sections of the tunnels pass through a variety of ground conditions including silts, sands, clay and rock and have been constructed using both top-down and bottom-up cut and cover construction techniques. The Yarra River Crossing is a 140 m length of the Domain Tunnel which crosses under the Yarra River on a relatively shallow alignment. The crossing of the river using cut and cover techniques was identified in the early stages of design development as being one of the most challenging stages of the works on the Southern Link. The prevalence of varying geological conditions combined with the need for maintained traffic and stream flow conditions provided a demanding and often conflicting set of criteria for which there appeared to be no one clear solution. A team of designers, constructors, estimators and specialist contractors were involved in a concept evaluation and risk analysis study spanning a period of approximately 12 months. During this study, four concepts were considered as likely contenders. This paper provides a brief outline of the four concepts addressing their relative merits, disadvantages and risks followed by a detailed description of the adopted solution, namely top-down construction using secant pile walling (east bank) and bottom-up in situ construction (west bank).

Jan 1, 1999