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By John Drobe, Robert M. Cann

"Abstract - The Minas de Oro Cu-Au skarn and replacement deposits are located in the highlands of central Honduras, 90 km north-northwest of the capital of Tegucigalpa.The deposits formed in Cretaceous volcano-sedimentary rocks following the emplacement of an early Paleocene granodiorite to dacite intrusive complex. Three types of skarn (Type IA, IB, and IC) and a low-temperature replacement mineralization (Type II) are recognized. Type IA skarn consists of massive brown-green andradite and lesser magnetite and pyroxene. Type IB skarn has magnetite + hematite as the main constituent and garnet <50%. Type IC skarn comprises >50% pyrrhotite + chalcopyrite with interstitial garnet or pyroxene. Au and Cu occur in potentially economic concentrations in all skarn types while other metals such as Ag, Pb, Zn, and Mo are locally present in significant quantities. The highly variable distribution and nature of the skarn deposits is controlled by: (1) intrusive activity, (2) composition of host rocks, (3) faulting and fracturing, and (4) attitude of host carbonates.Type II Au-Cu-As mineralization occurs in calcareous sandstone and conglomerate 2 km distal from skarns and comprises clots of Cu sulfides hosted within a zone of brecciation and quartz flooding. Garnet and/or magnetite skarn is not present and the mineralizing event appears to have been a low-temperature replacement type.The similarity of coeval Au-Cu-Fe skarns in central Guerrero, southern Mexico to Minas de Oro skarns, and the similar local stratigraphy is consistent with the generally accepted theory that the Chortis block originated from southern Mexico and during the Tertiary moved southeast to its present position."

Jan 1, 2000

By E. Allen

Quebec Cartier Mining Company operates approximately two hundred and fifty pieces of equipment in a climate with a temperature that has averaged 27.5°F during the last seven years. The use of special-purpose lubricants, fuels, antifreeze, rubber compounds, and alloy steels have reduced the cold-weather hazards. In some areas, high-cost cold-weather protective heating devices are being eliminated with experience.

Jan 1, 1966

By R. Cottam

The deformation and recrystallisation of magnesium yttrium alloys containing 0.23, 0.84 and 2.71wt% yttrium and commercially pure magnesium extrusion has been investigated at temperatures between 200 and 350°C. The alloys were produced as billets 7.5 cm diameter, solution treated at 525 °C for 8 h and extruded into 3 cm diameter bar at 390°C. Channel die compression was employed to deform the samples at a strain rate of 1x10-3s-1. For the 0.23 wt% yttrium alloy and the pure magnesium, dynamic recrystallization (DRX) occurred at all temperatures and the amount of DRX increased as the temperature was raised. In the alloys containing 0.84 and 2.71 wt% yttrium DRX was almost completely suppressed at all temperatures. The absence of DRX in the 0.84 and 2.71 wt% yttrium alloys was accompanied by a decrease in the ductility, except at 350°C the highest deformation temperature. It was observed that this increase in ductility was accompanied by a reduction in deformation twinning and the initiation of pyramidal slip. This work highlights the important role that DRX plays in enhancing the ductility of magnesium alloys.

Jan 1, 2006

By K. Ogawa, T. Yokoyama

Hydraulic fracturing technique, an applied technique to cause tensile fractures to rock by injecting water pressure to a certain closed section of the borehole, is a measurement method of in-situ rock stress. This technique has the highest track record for techniques used in sub 1000 meter. A feature of this technique is comparatively simple and easy for in-situ stress measurement, because the measurement is applicable when a drilled borehole is available. The predominant advantage of this method is that elastic constants such as Young’s modulus and Poisson’s ratio are not required for determining the value and direction of initial stress. The factors to determine the stress state are the water pressures of re-opening and shut-in of fractures around the borehole wall and its directions. With conventional methods, however, the accuracy of the derived stress states from the observation equations was often adversely affected by the lack of consideration of the remaining water pressure in fractures and insufficient stiffness of the pressurization system. We have developed a new hydraulic fracturing system based on a new test method concept overcoming these defects, and applied to a 300 meter deep borehole in granite. The most important improvement of the new system is an employment of a syringe pump which enables an accurate flow control of fluid with less than 1ml/min in the pressure of 30MPa. Therefore the new test system has a quick response for pressurising in the interval zone, and the measured data was confirmed extremely accurate.

Jan 1, 2015

By Robert B. Parsons

"It is quite likely that more than a handful of junior exploration companies will receive some startling news from their accountants this spring when 1989s tax returns are being prepared. These companies could find that, for the first time ever, they will have to write a cheque to the federal government on account of a new federal capital tax which became effective July I, 1989IntroductionMany mining companies which have never had to pay a federal income tax are finding that they indeed have a tax liability for 1989. Non-producing companies, such as junior exploration companies, almost automatically assume that they don&apos;t have to pay any income tax. But, a new tax imposed under the Income Tax Act catches especially the company that has no income.Effective July 1, 1989, a federal capital tax (some call it a corporation minimum tax) is payable by any corporate carrying on business in Canada where the corporation has ""taxable capital"" exceeding $10 million. As a result of the popular use of flow-through shares in recent years, many junior exploration companies are finding that their balance sheets show capital stock over $10 million, and that they are consequently caught by the new tax. Further, some of these companies are finding, to their chagrin, that the tax for 1989 was due on February 28, 1990, and that non-deductible interest is ticking away on unpaid taxes."

Jan 1, 1990

By C. Tissot, R. Palmer

"Due to the low concentrations of gold, direct measurement of gold concentration in ore on belt has not been seriously considered to now. Pre-concentration or sorting strategies have largely consisted of particle sorting based on secondary characteristics such as colour, which can be successful in select cases. CSIRO has produced sample measurement results using gamma activation analysis of ~300 gm samples with accuracies of around 30 ppb at best. With this encouragement, a feasibility study into gold ore measurement on belt for the purpose of sorting pods of gold ore has been undertaken. The study described here included, prototype design options with existing industrial Linacs, extensive Monte Carlo modelling of measurement sensitivity and shielding, further sample measurement, a study of the interaction of target measurement accuracy and sorting efficiency, and a rough estimation of potential economic benefit. The projected model sensitivity of around 0.1-0.15 ppm (1 standard deviation) in 10 seconds for 1 ppm average feed result in good bulk sorting performance and intriguing economic potential.INTRODUCTION Pre-concentration or sorting strategies for gold ores have largely consisted of particle sorting based on secondary characteristics such as colour or density, which can be successful in select cases (Klein, 2010). No method is available to measure gold content for sorting in particles or even in bulk on belt, principally due to the low concentrations of gold present. In fact, in many cases it is difficult to do rapid bulk grade measurements of base metal ores with concentrations many orders of magnitude higher. By a fortunate quirk of nature gold is particularly amenable to gamma activation analysis (GAA). CSIRO has performed extensive work in GAA of samples of crushed ore (Tickner, 2017). This has resulted in the Photon AssayTM technique that is currently being commercialised through the CSIRO spinoff company Chrysos. The technique relies on the recent availability of industrial high intensity X-ray sources such as Linacs which are currently being used in industry for security, medical and sterilisation applications. This development has led to CRC ORE funding a feasibility study to determine whether on-belt measurement of gold concentration is possible at a rate and accuracy sufficient to be useful for bulk sorting, where pods of ore are diverted rather than individual rocks. The study in the first instance is based on Monte Carlo modelling that has successfully predicted the performance of the sample based gold measurements. As well as the measurement feasibility consideration was also given to the likely heterogeneity of gold ores and hence the degree to which useful separation could be achieved. This is then tied to a back of the envelope evaluation of the order of magnitude economics of bulk sorting in an example deposit."

Jan 1, 2017

By E. R. Rivenbark

"The coal handling plant represents an investment of about $100 million in coal handling and storage equipment. The coal receiving is done by a continuous ship unloader that can handle ships in the 60 000 T range at Q rate of 1750 /ph. A unique feature in the system is a stacker/reclaimer unit which will work inside a dome storage structure. The coal for the unit will include any low sulphur coal that can be delivered by sea at an economical price blended with New Brunswick high sulphur coal.ThE flue gas scrubber is a wet limestone system capable of 95% SO2 removal. The scrubber will utilize about 150 000 tonnes of limestone per year and will produce commercial grade gypsum by the forced oxidization method.IntroductionWith the need for new generating capacity being required, New Brunswick Power reviewed, in 1985, its options for the next unit. The study indicated that the most attractive option for New Brunswick Power would be a coal-fired unit capable of receiving imported coal at a sea port. The site selection process resulted in three site options being considered.The existing Coleson Cove and Dalhousie sites, and the Belledune site were considered. To meet load distribution needs, it was then decided that the unit had to be located in the northern section of the province, thus eliminating the Coleson Cove site. The Belledune site was selected because it had the capacity to have additional units added where as the Dalhousie site would have only been able to accommodate one unit"

Jan 1, 1994

By J. E. Gill, A. R. Byers

The Surf and Pugsley gold-copper mines; owned and operated by Surf Inlet Consolidated Gold Mines; Limited; are about 6 miles inland from; the head of Surf inlet; on Princess Royal island; Skeena mining division; British Columbia. Surf inlet is a fiord 360 miles in an air line northwest of; Vancouver.

Jan 1, 1954

By W. G. McBride

THE present demand for men with engineering training exceeds anything in the history of the profession. Recent estimates indicate that mechanization of war has reached such a stage that at least twelve horsepower is required now for every one horsepower needed to run the machines of the first Great War. The scale of operations exceeds anything in the past, while more territory and people are involved than ever before. Many of our allies have inadequate or no facilities for producing the thousand and one articles absolutely necessary to the conduct of modern warfare. Lack of preparedness has made it necessary to produce at an unparalleled rate to gain parity with the enemy, while our losses have been so heavy that replacement, in itself, presents a task which might well stagger less courageous peoples. This means that not only is there an unprecedented demand for engineers to produce the machines, munitions, and supplies of war, but there is a correspondingly large need for men with engineering skill in the uniformed forces to operate and maintain the vast numbers of ships, &apos;planes, tanks, trucks, radios, and a myriad of other devices to carry on the varied activities of war. This abnormal demand came upon us after almost ten years of stagnation in the engineering industries. During this time many trained engineers drifted into other callings, while the lack of jobs for graduates caused a falling off in the number of men training for this profession. Consequently, the supply of well trained engineers was below normal when the madman of Germany precipitated us into the present turmoil. Added to all this, we in Canada are still suffering from governmental inefficiency in the utilization of the available supply of engineers. In the armed forces, engineers have been assigned to office and other work where their engineering training is not only wasted but for which men with more suitable training could be found. Mining engineers are debarred from service as aeronautical engineers, and students in mining engineering are denied the bursaries provided for aiding students in engineering. Mining and metallurgical engineers are both barred from the Ordnance department of the army. This arises from a misunderstanding in relation to engineering training. In Canadian engineering schools, all engineers are given a sound training in the branches of human knowledge which are fundamental to engineering: mathematics, physics, and chemistry. The basic difference between the several categories of engineers lies in the fact that training in the application of this fundamental knowledge to the solution of engineering problems is given in different subjects.

Jan 1, 1942

By CIM Standing Committee

The CIM Definition Standards on Mineral Resources and Reserves (CIM Definition Standards) establish definitions and guidance on the definitions for Mineral Resources, Mineral Reserves, and mining studies used in Canada. The Mineral Resource, Mineral Reserve, and mining study definitions are incorporated, by reference, into National Instrument 43-101 – Standards of Disclosure for Mineral Projects (NI 43-101). The CIM Definition Standards can be viewed at mrmr.cim.org. Readers should be aware that reports written by persons issuing technical reports that disclose information about exploration or other mining properties to the public in Canada are governed by a number of securities regulations.

May 10, 2014

By Daniel L. Cluff

The Canadian mining industry needs to find viable alternatives to the conventional cemented pastefill/hydraulic methods of backfilling open stopes for underground mines located within a permafrost zone. The harsh environment and the isolated location of a mine north of 60° impose additional challenges to standard backfill methods and opportunities to the technological and operational issues related to the use of frozen fill. Underground open stoping mining methods require the placement of fill material to enable the controlled recovery of ore from secondary and tertiary stopes. The typical design of the fill material requires the specification of inert material, water and binder. The permafrost conditions provide the additional parameter of subzero temperatures for backfill design and process control. The paper presents the results of an experimental field study, using large size samples, to determine the strength capacity of frozen backfill. The experimental work was performed utilizing rockfill and tailings material with moisture content consisting of water and ice crystals. Preliminary results indicate that the mixture of rockfill, tailings and moisture, develops strength that meet the demanded requirements for open stoping. A thermal equilibrium modelling analysis is presented in the paper.

May 1, 2008

By M. Mahfoud

The effect of grain refinement on the tensile and fatigue crack propagation behavior of sand cast magnesium alloy AM60B has been investigated in the present study, C2Cl6 in the amount of 0,3% was used to grain refine the melt, The fracture toughness tests were conducted in laboratory air at room temperature (25°C) using a sine-wave cyclic frequency of 20Hz and a load ratio of R = 0,1, The response in the Paris&apos;s regime and the critical stress range were determined, Preliminary findings have shown that C2Cl6 has a significant effect on both the tensile properties and fatigue crack propagation of the alloy tested, Grain refinement increased both the yield and ultimate tensile strength by more than 46%, and decreased the crack growth rate from 2,7 to 1,4 MPa Vm , However, the grain size seems to have a smaller effect on threshold stress intensity factor range. The fracture surfaces of specimens were examined optically and under the scanning electron microscope (SEM) to determine the relationship between grain size and fatigue properties.

Jan 1, 2005

By F. Barriga-Ordonez, J. A. Finch, L. Calzado, S. R. (Ram) Rao

Sludge, formed by lime treatment of acidic drainage and stored in tailing ponds of the Sudbury region, contains 5-7% Ni, mostly in a mix of hydroxides with Fe (~ 10%), Mg (~ 10%) and Cu (-0.5%), and Ca (-3.5%) as sulphate. Investigations were conducted to recover nickel by a 2-stage process. In the first stage, the sludge was leached with sulphuric acid at pH 3.2. About 90% of the nickel was extracted, producing a solution, which contained mainly nickel (2 g/L) and magnesium (3.7 g/L). In the second stage, nickel was separated by treating with ozone which recovered 99% of the nickel in the Ni(III) oxidation state as -85% pure nickel oxide-hydroxide (NiOOH) precipitate. The oxide settled and filtered readily. A potential use of the product in battery making is suggested. The leach residue contained 0.5% Ni making it less toxic for disposal. Some physical properties of nickel oxy-hydroxide and process parameters including ozone consumption will be discussed.

Jan 1, 2005

By Anoush Ebrahimi

Mining dilution is one of the most important factors affecting the economy of mining projects. Ore losses and dilution are present at all stages of mining and while several models can investigate the influence of dilution it is its quantification that poses the most serious challenge (Pakalnis et al., 1995). This paper introduces a methodology to quantify dilution factor in open pit mines. The proposed approach makes use of general mining software available in most mining companies. Therefore it is amenable to most mining operations and provides a readily available tool for understanding mining dilution for operators and consultants. To illustrate the methodology the author uses an example from a hypothetical mine. Dilution increases the operating costs in the mill by increasing the tonnage of material to be milled. In addition to its direct impact on short term income of a mine, dilution causes significant changes in other factors that on the long term reduce the overall value of the project. For example, it prolongs the mine life by reducing mill?s effective capacity. It also reduces the feed grade. In most cases, lower feed grade means lower mill recovery. Dilution also increases the cut-off grade which in turn reduces the overall ore utilization of a mine. In some cases, to take advantage of economies of scale, mining operations tend to plan for higher mining rates. Moving to a larger scale of operation means less selectivity, hence more dilution. This is true for all kind of deposits. High level and uncontrolled dilution may ultimately defeat the purpose of increasing production rates. If not impossible in theory it is nevertheless extremely difficult and expensive to eliminate dilution in practice. Some amount of dilution is practically unavoidable in most mining operations (Scoble and Moss, 1994). Although completely avoiding dilution may be impossible, we can measure and control it. By better understanding the root causes of the dilution and planning accordingly, it can be controlled and reduced. While we do our best to identify and calculate all the other cost items of a project, no matter how small, it is common to make general assumptions about dilution instead of quantifying it. It is common to assume a general dilution such as 5% for massive deposits and 10% for tabular shape deposits. While these figures may be a good starting point in early stages of mining studies, it does not take in to consideration the complexity of the problem. Dilution factor varies within a single mine for different benches and zones. This is due to changes we see in grade distribution and shape of ore body. It also varies based on commodity price. It is necessary to make sure that these variations are taken into account when designing or evaluating a mine. Dilution varies in different mines based on the deposit characteristics, operational aspects and economic cut-off grade. For instance, shape of the deposit, bench height, equipment size, and market conditions will have an impact on the level of dilution in a mine. It is paramount for mining projects to have a better understanding of dilution right from the beginning. In times like today, where mining operations must operate at peak efficiency, it is even more crucial to be able to calculate and have a better grasp of all the parameters influencing the economics of a project including dilution. In order to produce better project evaluations, dilution studies should be an integral part of any project.

Aug 1, 2013

By G. Viramontes-Gamboa

Approximately 70% of world copper reserves consist of the mineral chalcopyrite, and much international effort has focused on its study. Ultimate objectives include the development of environmentally friendly alternatives to smelting, and technologies to treat low-grade ores, for which concentration and smelting are economically unviable. Unfortunately, chalcopyrite leaching is inefficient in H2S04-Fe2(S04)3-FeS04 solutions, which is considered to be the most desirable oxidizing medium for leaching of copper sulfides, since the chemistry is well known, corrosion of industrial equipment is negligible, subsequent copper recovery by SXlEW is well established, and environmental impact is minimal. The main reason for this inefficiency is the self-passivation of chalcopyrite. We have devoted considerable effort in the understanding of this phenomenon, and have developed a predictive electrochemical methodology capable of establishing a priori the precise range of potentials within which chalcopyrite leaches and where it is passivated. Since potential control is a critical parameter in chalcopyrite leaching, this experimental methodology can be very useful for establishing the best conditions to leach chalcopyrite. In this paper, the scientific foundations of this predictive experimental technique are presented, and its practical application is demonstrated by comparing its predictions with leaching experiments from the literature.

Jan 1, 2007

By Pierre Sauvé, Alex Makila

"The Camflo stock of porphyritic quartz syenite is an irregular pipe-like body 200 metres in diameter injected along the axial plane of an E-W trending F2 fold, near the contact between the. Kewagama and Malartic groups. The stock plunges 55° to the NE, almost parallel to the fold axis. The stock, exhibiting pervasive, weak cataclasis with numerous, locally auriferous quartz veinlets, is cut by minor faults striking WNW and dipping about 45°NE.Two types of gold ore are distinguished at Camflo: ""porphyry"" ore and ""fault zone"" ore. ""Porphyry"" ore, accounting for 90% of the gold produced, forms wide zones within the stock. The zones are irregular in shape but tend to be oriented E-W in plan view (on a horizontal plane) and are elongated paraliel to the plunge of the stock. These zones are more abundant in the northern part of the stock. Differences between ore and barren porphyry are not obvious. ""Fault zone"" ore occurs outside the stock along minor faults, particularly in differentiated sills offer rodiorite and felsic granophyre. Gold grade is roughly proportional to the pyrite content which in turns depends in part on the original magnetite content of the host rock. Although both types of ore show some correlation between Au and S, the Au/S ratio is considerably higher in porphyry ore.The bulk of the gold is in quartz syenite and in felsic granophyre, the most brittle lithologies at the mine. Presumably, the vertically continuous, pipe-like stock, made up of shattered rock, provided the main channelway for the ascending mineralizing solutions."

Jan 1, 1990

By C. H. Hopper

THE gold orebodies of the Matachewan Consolidated mine are of particular interest geologically because of their odd shapes, their apparent lack of connection one with another, and the fact that they occur in a number of different formations. All of the orebodies exhibit a similar fracture pattern and the areas of fracturing appear related to the local folding. However, the lack of either horizontal or vertical continuity suggests additional controls not yet discovered. The question of origin, so ably discussed by H. C. Cooke in 1919, will be reviewed in the light of the additional evidence uncovered since his examination of surface trenches twenty-four years ago. The Matachewan Consolidated mine, with its neighbour, the Young-Davidson mine, is in Powell township, 25 miles by road northwest from Elk Lake, 30 miles west of Kirkland Lake, and 45 miles southeast of Porcupine. It may be considered as being on the westerly extension of the Kirk-land Lake sedimentary belt, where the rock column is markedly similar. There is no similarity in structure, however, for great ore-bearing shears and faults simply do not occur at Matachewan. Rather may it be said that the region, under stress, failed in isolated brecciated patches, some of which make up today&apos;s orebodies. The mine currently treats 1,000 tons a day of porphyry ore averaging 0.10 oz. gold per ton. It started operations in 1934 on greenstone ore, and the mill then treated 150 tons a day of ore averaging 0.23 oz. gold per ton. Total production to the end of 1941 has been 929,484 .tons averaging 0.160 oz. gold per ton.

Jan 1, 1942

By Kari Niiranen, Andreas Boehm

LKAB (Luossavaara-Kiirunavaara AB) is operating underground iron ore mine, with three beneficiation and pelletizing plants in Kiruna, Northern Sweden. The wet low intensity magnetic separation (WLIMS) is regarded as the crucial part of silicate mineral separation from the ore. The Kiirunavaara iron ore deposit shows a rather low content of silica (ca. 2.3 to 3.3 % SiO2) but the silica grade is expected to increase in the deeper parts of the deposit. This can be problematic in the case of DR pellet quality with an average silica grade under 0.75 % SiO2. A laboratory scale methodology was developed for the systematic characterization of the ore for mineral processing with the focus on silicates at the Institute of Mineral Processing, University of Leoben. This methodology is combining mineralogical, geochemical and process mineralogical characteristics. Automated mineralogy (QEMSCAN) was used to study the modal mineralogy, the distribution of silicate minerals in different particle size classes after comminution, the deportment of silicon (Si) between various silicates and degree of liberation and intergrowth of magnetite and silicates. Based on the mineralogical investigations, actinolite, phlogopite and even quartz and albite are the predominating SiO2 bearing minerals in the ore. The important result of the investigations was the discovery of two separate subtypes within the high silica ore type B2 based on their mineralogy and mineral processing characteristics. The crucial part of the investigations of intergrowths and liberation of magnetite results was the magnetic separation tests carried out with the Davis magnetic tube. The binary intergrowths of magnetite and the silicate minerals (mostly actinolite) are the most common type of mineral association discovered. The significant characteristics in the intergrowths of magnetite and actinolite are the fine-grained magnetite inclusions in actinolite which may end up increasing the SiO2 grade in the magnetite concentrate despite magnetic separation.

Jan 1, 2016

By R. Pakalnis, H. Miller, Madill. T.

"This paper describes a methodical approach to the estimation of the orientation and the magnitude of in-situ stresses. The study was performed at the Ruttan Mine, Sherritt Gordon Mines Ltd. , a 6,000 T.P.D. underground operation, located in northern Manitoba, Canada. It involves an initial estimate to be made based upon: structural interpretation • virgin stress measurements conducted in other areas (world wide, regional)The verification of the prevailing stress regime was made by conducting CSIRO hollow inclusion(1) overcoring measurements. The current cost for a virgin stress determination is about $7000 per measurement(2) and the difficulty encountered in attaining a good reading is high. This paper will describe the analytical procedures employed at Ruttan in evaluating the in-situ stress magnitude and orientation based on three overcore tests. It is proposed to perform an additional six measurements in order to verify the following results:Vertical stress = av (MPa) = 0.027 by depth (m)Major principal stress = o! """" 2.5 xav (340°/-20°)*Intermediate principal stress = a2 - 1.2xav (070°/0°)Minor principal stress = a3 """" o.8xov (160°/-70°)IntroductionThe Ruttan Mine of Sherritt Gordon Mines Ltd., a 6,000 T.P.D. underground operation, is located in northern Manitoba, Canada (Fig. I). The Ruttan copper-zinc orebody is a multi-lensed, steeply dipping (70 degrees) en-echelon deposit. Individual lenses have a maximum strike length of 350 m with widths varying from 7 m to 61 m. The mining method is o pen stoping with delayed backfilling and extends from surface to 860 m below surface."

Jan 1, 1985

By Kevin C. Milne

"The solution of problems associated with development of a sour gas reserve will be of increasing importance in tl1e next few years if gas export is approved •by the National Energy Board. The purpose of this paper is to review briefly the history of the Carstairs gas field, and tCI describe in a general manner the reservoir, and the producing and processing facilities.HISTORYThe Carstairs gas field was discovered in April 1958 when the discovery well, Home Carstairs 10-17, was successfully completed as a gas well in the Elkton member of the Turner Valley formation. Geo-graphic location of the field is shown in Figure No. 1. Note that the field is about five miles west of the town of Carstairs, Alberta, which in turn is about 40 miles north of Calgary. Drilling subsequent to the discovery well resulted in three addition-al producing wells and one dry hole during I.958; two producing wells during 1959; and one producing well and one dry hole during 1960. Thus, seven producing wells and two dry holes have been drilled in the Carstairs field to date.In November 1959 a 12-section block in the Carstairs field was unitized on a surface acre basis. Mean-while, in June 1959, operators in the field executed an ""Interim Plant Agreement"" that provided the money needed to start construction of a joint venture processing plant and gathering system. Construction of the plant and gathering system was completed in February 1960."

Jan 1, 1960