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CHALLENGES TO SCHEDULE/BUDGET Shortage of people (contractors, vendor support, engineering, staff) 2007 projects off the shelf Increase in metals prices Shortage of large tires Reserve increase Size of mine Unskilled labor force Community/government relations Limited access into valley English to Spanish SOLUTION Line 1 Line 2 concurrent construction, EPCM engineering review, advance scheduling Placed line 2 orders earlier Hedged currency, bulk orders Strategic alliances Flexible design Plan Deliveries Training, multiple contractors Engagement Built/upgraded roads Technical translators

May 1, 2010

By A. B. Barlow, D. H. Pitcher

"The Geophysics/Geochemistry Section of the Ontario Geological Survey initiated an aerial geophysical survey in the James Bay Lowlands, Cretaceous Basin area, District of Cochrane, Ontario. The survey was contracted to Scintrex Limited and was carried out in 1978. Approximately 8000 line kilometres of airborne electromagnetic and magnetic data were recorded. The Tridem airborne electromagnetic system was employed, mounted in a twin-engined PB Y Canso aircraft. This specific Tridem system uses a vertical coaxial coil configuration and measures in-phase and quadrature components of the secondary field at 500, 2000 and 8000 Hz.The primary purpose of this survey was to map subsurface conductivities and, in particular, to search for lignite deposits. Physical property measurements show that electrical methods should detect differen ces in conductivity between the moderately conducting clay-lignite horizons and the less conducting clay, soil, muskeg and gravel horizons. A preliminary Tridem test survey, as well as surface DC resistivity soundings, confirmed this approach. The interpretation of the present survey data indicates that Tridem is a suitable electrical method to aid lignite exploration in the James Bay Lowlands."

Jan 1, 1980

By D. A. Beck

The load-deformation response of discontinuous rock under static and dynamic loading conditions has been simulated using Explicit Finite Element models. The intent of the analysis was to investigate the effects of specimen size and confining stress on strength, dilation and comminution. The simulations allow the development of homogenised constitutive material properties for discontinuous rock masses using laboratory scale measurements and representative Discrete Fracture Networks (DFNs). A procedure for this is presented which includes a comparison of measured seismic response in a mine to the Dissipated Plastic Energy (DPE) that is released in the simulated rock masses. The models also show how confinement and scale affect the stress-strain and DPE response of the simulated rock specimens, reproducing a number of known rock phenomena that are often poorly captured in geotechnical modelling. A case study is presented showing a satisfactory match between the model-derived, homogenised material properties and values achieved by calibration of a mine-scale model where many thousands of seismic, displacement and damage measurements were available.

May 1, 2009

By Dillon. Patricia

Business Growth ?Coal ?Targeting 30 million tonnes by 2013 compared to 19 million tonnes produced in 2009 ?Expanding Energy Business unit (Oil Sands) ?Copper -Strong growth potential for existing operations and development projects ?New gold strategy recently launched ?New markets for zinc Need to retain existing and attract new employees to support growth Engaged Employee ?Has a positive attitude towards the organization and its values ?Is a person who is fully involved in, and enthusiastic about, his or her work Engaged employees are more likely to stay with the organization.

May 1, 2010

By B. Kruger

The Dundee Precious Metals Tsumeb Smelter has evolved over the last decade to meet the challenges and opportunities brought about by a changing copper concentrate market, technological advances, environmental legislation as well as social and political changes. The paper discusses some of the challenges, successes and lessons learnt through the expansion and modernization of its smelter complex. It considers the details and impact of the transition from slag granulation to that of slag slow cooling as well as the improvement program that was implemented to more than double the refractory campaign life of the Ausmelt furnace from around 6–9 months to 15–18 months. In addition, given the evolving world we live in, it considers the challenges that the smelter faces today, not the least of it being how to remain relevant in an age of digital and other 4th Industrial Revolution disruptions. INTRODUCTION Dundee Precious Metals Tsumeb (DPMT) Smelter is located just outside the town of Tsumeb, in the Oshikoto region of Namibia. It is the largest town in the region with a population of approximately 45,000. The smelter was built in the early 1960s to treat concentrate from the nearby Tsumeb copper mines. Construction of the site was completed in 1962 and the smelter was officially commissioned in 1963 by Tsumeb Corporation Limited (TCL). At the time the smelter consisted of a lead section (including a refinery), a copper section and plants that produced cadmium, sodium antimonite and arsenic trioxide. Production commenced in early 1964, with 3,500 tonnes of copper and 6,000 tonnes of lead being produced per month. TCL was acquired by Gold Fields South Africa in 1988, and a few years later the lead section was shut down due to reduced lead content of the mined ore. In mid-1996, all mining and smelting operations were halted due to labour strikes. Ongopolo Mining and Processing Limited (OMPL) re-opened the mines and the smelter in 2000, only operating the copper section of the smelter. At the end of 2008, all mining operations were halted by the new owner of OMPL, Weatherly Mining International, while the smelter continued to operate. The closure of the Weatherly owned mines in Namibia, the primary feed source to the Tsumeb Smelter, meant that the smelter had to transition its business model from operating as a ‘captive smelter’ to that of a ‘toll smelter’. Its Ausmelt Top Submerged Lance (TSL) smelting technology and various ancillary plants made it especially suitable for accepting and treating complex concentrates that were available on the global market.

Jan 1, 2019

By Jochen Petersen, Alison Lewis, Cledwyn Mangunda

Run-off and waste water streams high in dissolved metal content are generated in all mining operations. The metals pose a threat to life due to their persistent bio-accumulative toxic (PBT) characteristics. Hence, there is a need to treat mine waste water effectively. Lime precipitation is the technology of choice through which Fe, as the major metal species, is removed as Fe (III) oxyhydroxides with other metals co-precipitated and/or adsorbed. Sulphates are removed as gypsum or incorporated into the Fe phases. The resulting sludge has poor dewatering characteristics and is deposited in landfills, with an inherent risk of returning the Fe back into the water cycle through leaching. This study seeks to understand the mechanisms behind the formation of this sludge in terms of product quality. The relationship between process conditions and product characteristics has been investigated through exploring the effect of Fe (III) concentration on the precipitate product characteristics (particle size distribution (PSD), size, morphology and structure) and quality (in terms of filterability, settling ability, etc.) in a simplified system. Neutralisation of acidic synthetic aqueous Fe (III) sulphate streams containing 50, 400 and 800 mg/L Fe(III), respectively, was effected by mixing it in a continuous stirred tank reactor (CSTR) with dissolved calcium hydroxide for pH control at a residence time of 15 minutes. Precipitate samples analysed for morphology and PSD, using nanoSEM and Zetasizer respectively, showed a general decrease in PSD and zeta potential with increases in feed Fe (III) concentration. These results were used to infer the particle size enlargement mechanisms of Fe (III) oxyhydroxide precipitates under a given set of operating conditions. Preliminary product quality results indicate that a high concentration (800 mg/L) leads to the rapid formation of metastable precursors with poor product quality, whilst a low concentration (50 mg/L) leads to formation of thermodynamically more stable precipitates with good product quality. The approach demonstrates a potential route forward in terms of linking operating conditions to the attainment of desirable characteristics rather than specific precipitate phases which are difficult to identify.

Jan 1, 2016

By T. Gerritsen, T. Plikas, K. Ochoa, M. Loveless, R. MacRosty, J. Reichart, R. Pula

Sidewall accretion in a smelting furnace plays an important role in furnace integrity as it provides protection to the sidewall cooling elements and thereby extends the furnace campaign life. The extreme thermal and mechanical stresses in the furnace and changes in the slag chemistry can cause the sidewall accretion to melt or break away decreasing the lining protecting the cooling elements. Thin accretion is highly undesirable as it increases the risk of exposing the cooling elements to the molten bath and in the worst case may lead to a failure. Therefore, monitoring the sidewall accretion on an operating furnace is extremely important to manage furnace integrity and to support safe furnace operation. Operators often generate estimates for sidewall accretion and refractory thickness using either copper cooler temperatures or heat load into the cooling water circuits. Multivariate statistical models, on the other hand, have the capability to consider all the process measurements simultaneously to provide a more reliable estimate. This paper describes the application of multivariate statistical models for sidewall integrity monitoring on a Flash Converting Furnace (FCF) and also discusses the online implementation of these models as the Sidewall Accretion Monitoring System. INTRODUCTION Rio Tinto’s Kennecott Utah Copper (KUC) smelter located near Salt Lake city, Utah operates a Flash Smelting Furnace (FSF) and a Flash Converting Furnace (FCF) to produce high-grade matte and blister copper respectively. Since the commissioning of smelter in 1995, several improvements were made to these furnaces to increase their efficiency and operational safety. At present, Kennecott smelter is known to be among the lowest-emission and highest energy recovery copper smelters in the world. Since the smelter start-up, Kennecott has invested in several advanced furnace monitoring practices to evaluate the integrity of the furnaces and improve their campaign life. An example is their temperature monitoring system installed for the smelting and converting furnaces, which continuously monitors the furnace sidewall temperatures and notifies the operators during temperature excursions. During an investigation on the converting furnace, it was revealed that there were frequent temperature excursions in the settler sidewall area towards the reaction shaft end of the furnace that caused significant furnace downtime. The reason for the sidewall temperature excursions was not clearly known.

Jan 1, 2019

By Gonzalo Bernstein, David G. Meadows, German Naranjo, Edgardo Tapia

"During the last decade Antofagasta Minerals’ Los Pelambres Mine has dramatically increased its ore throughput following the fast initial phase ramp up through a series of planned incremental expansions. The original 85,000 mtpd, two SAG line plant was commissioned in 1999 and rapidly exceeded nameplate tonnage in only a few months. Following this, the inclusion of a pebble crushing circuit resulted in throughputs in excess of 114,000 mtpd and a recent, final third line SAG and ball mill addition have taken the plant to over 175,000 mtpd even with increasing ore hardness and changing ore feed characteristics. The progressive changes are described in this paper together with how the technical challenges have been met.INTRODUCTIONMinera Los Pelambres is a world class copper-molybdenum operation located in the Salamanca area in Chile, in region four, approximately 500 km north east of Santiago, the capital of Chile. In the late 1990s Antofagasta Minerals developed the Minera Los Pelambres project in Chile at an investment cost of approximately $1.3 billion USDs. The project construction was successfully led and completed by Bechtel Corporation in 1999 and within a matter of months the plant was already exceeding the nameplate capacity of 85,000 mtpd. In 2001 a pebble crushing circuit was added to raise the capacity to 114,000 mtpd. In the early part of 2003-2004, it was recognized that the hardness profile was changing with depth and that in order to maintain the plant capacity additional power would be needed in the SAG mills together with upgrading of the primary crusher. In conjunction with these changes a fifth ball mill and a second primary crusher station would also need to be installed. A further detailed engineering study and evaluation was initiated by Minera Los Pelambres. This was lead by Bechtel Corporation with major design contributions from FLSmidth and Siemens in order to establish the re-powering requirements for the SAG mills. These re-powering changes together with the inclusion of a pebble crushing circuit took the plant to up to 125,000 mtpd even with harder more competent ores. Finally in the last two years an additional grinding line has been added to take the capacity to consistently over 175,000 mtpd. The third line was installed in a record time of 256 days. A schematic of the current comminution circuit, discussed in this paper, is shown in Figure 2."

Jan 1, 2012

By D. C. Brady

"Within six months from award of a project management contract, Les Mines Dumagami Limitée, Cadillac, Quebec, was operating its new hoisting facility. This was accomplished with less than a six-week shutdown of mine production while still maintaining shaft access for underground maintenance.The work involved installing a refurbished /3.5 ft diameter double drum hoist, replacing a timber headframe with a newsteel headframe, increasing the ore bin capacity from 500tons to 1000 tons, constructing a new substation, and upgrading related facilities.This paper describes the work and methods used by various contractors, Les Mines Dumagami Limitée and J.S. Redpath Mining Consultants Limited to bring this project to a successful completion. It discusses the history of the project from proposal stage through to the design, procurement, scheduling, and construction management. The paper also comments on problems that were encountered and the methods used to overcome them.IntroductionThe Donald J. Laronde Mine of Les Mines Dumagami Limitée (Dumagarni), a gold and copper producer, is located in northwestern Quebec, approximately half way between Val d'Or and Rouyn. The mine started production in the spring of 1988 and the first gold bar was poured in June 1988.Following a request by Dumagami, on February 22, 1989, J.S. Redpath Mining Consultants Limited(Redpath) delivered a proposal to increase hoisting capabilities from 1500 tpd to a minimum of 2500tpd. Although various concepts were considered, Redpath proposed a new hoist house along the same shaft axis as the existing hoist, and located on the site of the existing substation. They would then provide a new substation, replace the headframe with a largersteel structure , gain extra storage capacities by increasing the bin heights, and raising the roof of the bin house accordingly.Although underground mining would have to be stopped for a month, the mill production would be maintained by feed from Dumagami's open pit.Figure 1 shows the original plant layout and Figure 2 represents the general arrangement after the project was completed . Table 1 compares the original hoisting facilities to the new facilities.On March 2, Dumagami awarded Redpath a contract that included preliminary engineering, detailed engineering, procurement and contract administration, and later added construction management. The preliminary engineering refined the initialconcept, selected major equipment, and prepared schedules and capital cost estimates for the total project."

Jan 1, 1991

Agenda ? Where?s Victor ? What work was done to get approval to spend $982m ? a brief history ? Some project facts ? The triple bottom-line accomplishments to date ? Construction A Brief History of Victor ? 1960?s ? first sampling in area ? 1980?s ? stream samples and Victor kimberlite discovered ? 1990?s ? test / bulk samples ? 1999 / 2000 ? large bulk samples ? 2000 / 2003 ? technical evaluation through to Feasibility Study, permitting process

May 1, 2006

One Data Set for the Lifecycle Complete data captured at the logging stage benefits the entire life cycle Exploration Technical Studies Production and Milling Visible Light Spectrum Hyperspectral, put simply, is the interaction of light with matter based on the nature and chemical structure of the specimen. SpectrumWe develop the library to match the liberation size fraction Analyses every 1mm2 1 meter of NQ core = 35 000 analysis data Crystal size detection : 0.1 micron

May 1, 2013

By Tom Shumka

Introduction ?This technique detects 100% of all gear tooth surface indications, providing comprehensive data, and has the ability to size indications accurately. ?The remarkable advantages of ECA technology, is improved inspection capabilities and significant time-savings. ?The advantage of using EMCD is its ability to size indications accurately. ?This technique does not require the gear teeth to be wiped down by hand after cleaning as in MT, LT or UT inspections. (Figure 1) ?This technique will inspect one gear tooth in 30 seconds. ?All of the data can be archived for future comparisons in an electronic report. Methodology ?This technique utilizes Eddy Current Array (ECA) as the principle inspection technique. ?What has been added are specialty scanner probes with multiple coils, a multiplexer and a software package. ?With 2 and 3D dimensional isometric displays, the defect can be seen electronically as it is on the gear tooth surface, thus, reducing the reliance on human interpretation.

May 1, 2011

By David J. Morrison

Scarcity of truck tyres, increasing cost and decreasing availability of labour, increases in fuel costs and project budget blowouts have changed the paradigm behind mining equipment selections. The cycle of commodity changes have occurred in parallel with the increasing maturity of continuous mining machinery, mobile in-pit crushing systems and very large scale conveyor belt systems. This paper will consider the merits of operating continuous materials handling systems, mobile in pit crushing systems, relocatable crushing systems, relocatable conveyor systems and automated waste handling systems in place of the more conventional approach of truck haulage.

May 1, 2007

"The gravimetric dust sampler is one of the tools now available to the industrial hygienists for determining the worker 's exposure to the numerous types of particulate matter that may be present in the workplace. The paper ' reviews the different sampling trains that can be used for the two major criteria for respirable dust and some of the sources of error in this dust assessment technique.IntroductionIt may be stated simply that the measurement of airborne dust in the working environment is done for one or two reasons: namely, for engineering control purposes and! or to evaluate the potential for toxicological insult arising from the inhalation of dust particles.This paper reviews the progress made in the development of dust-assessing instruments, particularly the gravimetric types designed to meet British and U.S. dust criteria , and discusses the limitations in their use for this purpose."

Jan 1, 1981

By D. F. Sherwin

"THE AREA which is described in this paper (Fig. 1) includes the continental margin of eastern Canada extending from the Gulf of Maine to the north edge of the Grand Banks, which, including the continental shelf, slope and rise, comprises an area of about 600,000 square miles. The paper is intended to give a background of the geological setting of this region in the context of its ultimate potential for oil and gas reserves in close proximity to the Nova Scotia energy market.HISTORY OF EXPLORATIONThe history of geological exploration of this area really began in 1878, when U.S. fishing boats brought back samples of rock recovered in trawls from their expeditions to the long-famous fishing banks off Canada's East Coast. Tertiary and Cretaceous fossils recovered from these samples indicated that the eastern Canadian continental shelf was actually the submerged northern extension of the Atlantic Coastal Plain."

Jan 1, 1972

By Robert D. Brown

"The Conservative Government 's budget proposals brought forward on December 11, 1979 have been withdrawn, but they are far from dead. On the contrary, a number of those budget proposals, especially the ones which would close loopholes and result in other technical changes being made to the Income Tax Act, should be considered to be alive and well.It is not unreasonable to expect the next government, of whatever political persuasion, to reintroduce many of these technical changes in the next federal budget. For that reason, last December's budget may have offered an interesting preview of what the mining industry and other taxpayers can expect in 1980. It is quite possible that some of these changes may be effective as of the original dates announced in the withdrawn budget proposals.This month, ""Tax Notes"" reviews the main pro visions of Mr. Crosbie's December, 1979 budget, with a primary focus on the changes that would have affected the resource sector.It must be emphasized that all of the budget proposals discussed herein have been withdrawn, that none of them are law and that any actual changes in our tax rules will have to be dealt with by the new Parliament that will be assembled following the February 18 election. December 1979budget withdrawnThe federal budget proposals brought forward by Finance Minister John Crosbie on December II, 1979 were withdrawn as a result of the defeat of the Conservative Government on a motion of non-confidence in the House of Commons on December 13. However, it appears quite possible that at least some of the proposals may be introduced into Parliament at a future date, possibly with retroactive effect.In a press release issued by the Department of Finance, Finance Minister John Crosbie stated that if the Conservative Government is returned to power, it will reintroduce all of the measures contained in his December II budget.Mr. Crosbie stated that all of the income tax measures contained in the budget would be reintroduced, effective on the dates indicated in the Notice of Ways and Means Motion tabled on December II. Some of the more important measures in December II budget, and their effective dates as indicated in the Notice of Ways and Means Motion, are discussed below.The December budget had also introduced or increased excise taxes or duties on gasoline, wines, cosmetics and photofinishing. If the Conservative party is re-elected, these measures will be reintroduced with prospective effect (i.e . effective as of new dates to be announced in the new budget)."

Jan 1, 1980

By L. S. Jen

Canadian copper, nickel, zinc, lead and molybdenum mines are characterized by the mining of ores from which more than one metal is recovered. During the 1980s, approximately 15% of the gold, 25% of the zinc, 30% of the copper, 55% of the molybdenum, 80% of the silver and 90% of the lead produced from Canadian mines were produced as co-products and by-products of base metal mining operations. This trend is not expected to change significantly in the near future. The presence of co-products and by-products affects the level of production and the level of revenue from base metal mines in several ways: (I) in general, production of one base metal cannot be expanded or cut back without affecting the amount of production of another metal;(2) the commercial success of certain base metal mining operations depends on the substantial bonus revenues from co-products and by-products; (3) the quality and economic viability of many ore deposits are significantly improved by the presence of co-products and by-products; and (4) while coproduction is critical to the survival of some mines, bonus revenue from by-products can also be life saving to others during economic downturns. For these reasons, deposits with significant co-product or by-product values are likely to continue to be significant targets for exploration and for acquisition.

Jan 1, 1992

By Peter J. Franklin

"Short-term mine planning of open pits is an activity that has historically been carried out by hand. Typically, the use of computers has played little part in this type of mine planning. This paper describes the objectives and the procedures involved in short-term mine planning, comments on the type of computer systems available, and describes in detail a computer-aided short-term planning and scheduling system known as STEPS.IntroductionThe mine planning department of any o pen-pit mining operation performs a wide variety of different tasks. However, their primary concern is the preparation of detailed long-and short-term mine plans. These mine plan s will define the long-term operating strategies and definitive everyday working plan s for the ongoing development of the open pit.In this day and age, when operating costs have spiralled upwards due to inflation , and product revenues have decreased due to depressed economies and poor markets, it is vitally important for all aspects of the mining operation, including mine planning, to be efficient and cost effective.There are numerous options available for planning engineers when generating a mine plan. A cost effective mine plan must investigate all these options and select the optimum. When using manual planning techniques, it is often impossible to evaluate all the available options. To do this, and to produce an optimum mine plan, a computer is required.This paper discusses mine planning, with emphasis toward the short-term plan and comments on how the processes may be computerized. It also describes in detail, a computer software system called STEPS, which has been designed as an interactive graphics, computer-aided short -term mine planning and scheduling tool."

Jan 1, 1985

By J. E. Nesset, E. R. Bobicki, K. L. Bilaniuk

The introduction of froth flotation technology in Canada, and in particular, in British Columbia, began not long after it was successfully applied in the Broken Hill mining area of Australia which began around 1905. It proved to be a revolutionary and transformative technology that resulted in marginal operations in copper, lead and zinc becoming profitable in spectacular fashion. The paper presents the technology of both oil flotation and froth flotation in the context of the challenges of the time and its early application in British Columbia at the Le Roi No.2 mine (1903), the Britannia Copper mine (1912), and at the Allenby concentrator of the Copper Mountain mine (1918-19). New-found archival documents indicate the Britannia application to be the first production application of froth flotation for copper ore outside Australia, a claim that is currently made by the Braden mine (now El Teniente) in Chile. Flotation was initially an add-on process following gravity methods but was rapidly shown to be far superior method for the bulk and selective recovery of metal sulphides. Flotation proved particularly successful for the recovery of zinc sulphide (the so-called ‘zinc problem’) which was considered a contaminant at the time. The ‘copper problem’ related to the poor recovery of fine copper sulphide particles that were not amenable to gravity methods. The success of flotation led to changes in both the scale and methods of mining, concentration and smelting in a manner that allowed integrated mining companies to flourish. Many are still with us today. INTRODUCTION The advent of froth flotation in the early 20th century was truly a revolutionary technological development, not only for the mining and metallurgical industries, but arguably more so for business and society overall. The Canadian technology historian Jeremy Mouat stated (1996) “The development of flotation was the greatest single metallurgical improvement of the modern era...it is not overstating the case to claim that flotation was of central importance to the smooth functioning of the global economy”. It should, therefore, be a story of interest to us all. The aim of this paper is not to retell the full story, that has been well covered by others (Hoover, 1912; Rickard, 1916a; Hines & Vincent, 1961; Lynch et al., 2010) but rather to add some Canadian perspective and the key role played by companies and individuals in those early days, focusing on events in British Columbia’s copper industry. EARLY DEVELOPMENTS During the later half of the 19th century, a number of flotation-related patents were issued. These include the 1860 patent (Britain) granted to William Haynes for a process to separate sulphides from ground ore by mixing it with oil (1-10% wt) followed by a separation process in a water-filled vessel; the 1877 patent granted to Georg and Adolph Bessel (Germany) for a process involving the mixing of oil and graphite ore followed by boiling in water to produce a high grade graphite froth (>90% carbon); and the 1885 patent granted to Rebecca ‘Carrie’ Everson for the separation of sulphides by mixing sulphide ore with small quantities of oil, and adding water followed by sulphuric acid. These processes are more properly referred to as bulk oil flotation due to the relatively large quantity of hydrocarbon used.

Jan 1, 2019

By Steve McMullan, Blaine Webster, Ian Johnson, Ron Matthews

"Time domain spectral Induced Polarization (IP) data from the Tower, Jojay and Laurel Lake gold deposits in northern Saskatchewan are presented. The resistivity data shows both resistivity lows (due to fault, shear or alteration zones) and resistivity highs (due to silicification) in the area of the deposits. The high resistivity zones suppress and distort coincident IP responses, calling f or high quality surveys and special care in interpreting the IP data.Electromagnetic methods are not effective in locating the deposits. This is due, in part, to masking by conductive cover. The Jojay Lake deposit has a strong magnetic response. A more indirect magnetic association is seen for the Tower Lake deposit. The Laurel Lake deposit has no magnetic signature. Magnetic data are useful in defining structure in all cases.All three deposits are outlined in the IP survey results. IP anomaly amplitudes from the pole-dipole array are from two times (Tower and Laurel Lak e) to six times (Jojay Lake) background values. Gradient array IP anomalies are of less amplitude. The spectral time constant is short for the Tower and Laurel Lak e deposits and long for the Jojay deposit. This implies that the metallic sulphides in the Jojay deposit are more interconnected than those of the other two deposits. INTRODUCTIONInduced polarization / resistivity surveys are commonly used in gold exploration program s in the Canadian shield because the IP method is effective in detecting disseminated metallic sulphides which are often found associated with gold. Other common geophysical sur vey methods such as magnetics, VLF and EM are not generally capable of direct detection of disseminated sulphides. Since the introduction of the IP method in the 1950s, it has undergone continuous improvement. The most recent improvement is the development of time domain receiver s which sample the full de cay and record it in digit al form. This results in a more complete measurement of the response which permits analysis and enhancement of data quality and the derivation of a nomaly parameters which characterize the measured decay. This extension of conventional time domain IP methods is called spectra l IP, a term first introduced by Pelton et al. working in the frequency domain Spectral IP surveys are attractive because they allow the possibility of discriminating between IP responses which have similar amplitudes but are due to dissimilar geo logic targets. The discrimination can be important in the selection of IP anomalies for follow-up.Time domain spectral IP survey results are presented over three known gold deposits in northern Saskatchewan-Tower Lake, Jojay Lake and Laurel Lake. The surveys were initiated and supported by Cameco-A Canadian Mining and Energy Corporation (formerly the Saskatchewan Mining and Development Corporation-SMDC) and were carried out by JVX Limited using the Scintrex IPR-II receiver and attendant spectral analysis software."

Jan 1, 1989