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By Link. Theo A.

Introduction Since the discovery of a major oil pool at Leduc, Alberta, on February 13th, 1947, the long spell of 'oil drought' in Western Canada is now being turned into an oil and gas flood which requires immediate action to obtain the optimum economic benefits. The Woodbend, Section 9, and Okalta extensions of the Leduc field itself have been established; the Redwater pool, lying thirty-seven miles northeast of Edmonton, has been discovered and is being drilled up, and the Imperial Schoepp No. 1 or Golden Spike discovery holds promise of something phenomenal in view of the 500 feet of oil-saturated coral-reef porosity whose areal extent is not known. Imperial Stanolind Barrhead No. 1, northwest of Edmonton, revealed the presence of oil in the Madison, and just recently Gulf N.J. Ellis No. 1, some sixty miles southeast of Leduc, found commercial production in the Leduc D-2 discovery zone. In addition to these Paloeozoic discoveries, gas and oil reserves have also been established in the Upper and Lower Cretaceous, which must be penetrated by all tests on the way through the geological column to the Devonian. If ever there appeared to be an index of 'things to come' in the oil industry, this is it. However, without these recent discoveries the picture in Western Canada does and always did, look very promising indeed. A brief survey of the geological setting in Western Canada is the object of this contribution.

Jan 1, 1949

By Jasmin Raymond

Ground source heat pumps are used to heat or cool building and heat water supply. Such heat pumps use the earth as a heat source or sink to efficiently provide or store thermal energy. For example, a ground source heat pump typically requires less then a third of the electric or fossil fuel energy of a conventional heater. Ground source heat pumps could therefore help reduce the energy consumption of active mines where low-grade geothermal resources are abundant. In most heat pumps, water or a water-antifreeze mixture having a temperature ranging from -6.5 to 43.5 °C is circulated through a heat exchanger at a rate of 0.000033 to 0.000067 m3/s (2 to 4 L/min) for each kilowatt of heating/cooling capacity. The groundwater that is continuously pumped to drain mines could be used to operate heat pumps. Water feeding a heat pump can alternatively circulate in a close loop network of pipes buried underground or installed in a surface water body. Retention water ponds, tailings and waste dumps commonly found at active mine sites could provide excellent environments to install the close loop system. Further research will help take advantage of the unexploited geothermal resources associated with actives mines.

May 1, 2007

By William M. (Bill) Shaver

"The author will review the early history of shaft sinking as well as focus on the improvements made in shaft design and construction over the last fifty years (1970 to 2019) to predict how shaft sinking will change over the next fifty years and describe what the shaft sinking world might look like in 2070. INTRODUCTION It is a great honour to be one of your keynote speakers for the Fourth International Conference on Shaft Design and Construction being held in Toronto in November 2019. This is one of the opportunities we have to thank the Mining Companies of the world as well as the industries and companies we serve for their support of the mining contracting and shaft sinking business of Canada and the world at large. Many of these companies are represented here today. Without your support many of the innovations we will talk about today would not be possible. We would also like to thank all the companies that work with us in our business including all the contractors and suppliers who provide the various services we require. These include equipment manufacturers, engineering companies, project management companies and suppliers large and small who cater to our every need as quickly as possible. Without all these partners we would not be as good as we are. Many of these companies are our sponsors this week. Thank you from all of us! This is also an appropriate time to pause and think about those Shaft Sinkers we have lost and those who have been injured on our projects around the world. Please bow your head and remember the Shaft Sinkers you have worked with, who did not return home or those who returned home injured. Think about how we can continue the work of making shafts safer every day as we go forward with our projects so everyone goes home to their families safe and sound. Pause for a minute and thank you. The subject matter we have chosen to discuss today is “Shaft Sinking in the Next Five Decades”. How will the work be done, how fast will it be done, what will it cost, and why we think this may occur? It is appropriate to consider this over the next few days with this auspicious group we have assembled. Today, we will look back at all the advances that have been made over the last many years and look ahead to the future to attempt to predict what shaft sinking will look like in 2070. When I look around the room I recognize that many of us will not be around then so we need not worry about being wrong. Suffice it to say that the next 50 years will be very interesting and exciting for the shaft sinking business."

Jan 1, 2019

By Jie Deng, Wenliang Xiong, Binyan Chen

"With falling rare earth metal prices, low cost beneficiation of rare earth minerals is essential. The “Flotation-Agglomeration-Magnetic” (FAM) separation process is a newly developed technology by IMUMR to economically recover rare earth elements from different types of deposits. The theory of FAM process is to selectively agglomerate rare earth particles and separate from gangue minerals by bubble flotation process. The flotation product is further upgraded by magnetic separation. The FAM process has been successfully applied in industrial production on the Dalucao rare earth ore, Sichuan, China. The average REO grade of rare earth concentrate is 65% in the latest 12 month production run, with an average recovery of 55%.INTRODUCTIONRare earth elements (REEs) include fifteen lanthanide elements coupled with two chemically similar elements (yttrium and scandium). These elements are split into two sub-groups, La to Sm are classified as light rare earth elements (LREEs) and the remaining elements including yttrium are heavy rare earth elements (HREEs) (Kumari & Panda, 2015). The demand of rare earth elements surged in recent years due to their increasing usage in diverse industrial aspects including high strength magnets, phosphors, clean energy, polishing compounds and catalysts (Goley &Scott, 2014).More than 250 REE-bearing minerals have been discovered, but many minerals are with very low concentrations of REEs, varying from 10-300 ppm (Adam &Ping, 2013). The most common rare earth minerals mined are bastnaesite, monazite, xenotime and ion-adoption REE (Chelgani & Rudolph, 2015; Kanazawa & Kamitani, 2006). Before the 1960s, most rare earth resources were extracted from monazite in the beach placer, with the exploiting of Mountain Pass in the United States and Bayan Obo mine in China, bastnaesite became the chief mineral source of rare earth resources (Klinger, 2015). These minerals are commonly separated with gangue minerals by froth flotation, gravity concentration, magnetic separation, or any combination thereof based on their specific physical characteristics (Zhou & Wang, 2014; Adam & Richard, 2014; Yang & Satur, 2015; Xia & Brian, 2015a,b)."

Jan 1, 2016

By A. F. Matheson

"Bankfield Consolidated Mines, Limited, and Tombill Gold Mines, Limited, in the Little Long Lac area, Ontario, mined an orebody that was common to both. The discovery' of this orebody was made by surface prospecting in May, 1932, on Bankfield ground, following an original discovery made in the same manner on the same property on a small reef in Magnet lake in October, 1931. The production from the two mines between 1937 and 1942 was approximately 135,000 oz. gold from about 420,000 tons of ore, an average grade of 0.32 oz. a ton. Production was nearly equally divided between the two properties. Both mines are now closed, the ore exhausted.""The ore is mainly sheared and fractured greywacke and porphyry impregnated by silica and small amounts of metallic minerals. To a lesser extent there are definite quartz veins in the ore zone""(l). The metallic minerals present were principally pyrite, arsenopyrite, pyrrhotite, and native gold .As at other mines in the Little Long Lac area, an elongated, broad, deep trough of folded, steeply dipping volcanic and sedimentary rocks, striking roughly east-west and surrounded by younger granite, is host to the orebodies of the Bankfield and Tombill. In the immediate area of the two mines iron formation and conglomerate bands occur nearby both north and south of an intrusion of porphyry-Cliorite, suggesting repetition of beds and folding. Although considerable drag folding is in evidence, folding on the above scale has neither been proved nor disproved."

Jan 1, 1954

By G. Barrasso

REACH was proposed by the EU Commission in October 2003 and stands for the Registration Evaluation, Authorisation and Restriction of Chemicals. It requires that all substances identified as persistent, bio-accumulative and toxic, whether the risk of those chemicals being released is real or perceived, require registration prior to them being allowed to be imported into the European Union. An internal investigation by the metals industry indicates that almost all primary raw materials streams would be classified as hazardous due to the potential health or environmental hazard properties of one or more of their ingredients. REACH uses a wide definition for chemicals and metals and as such its implications greatly impact the entire supply chain of the metals industry. The process of registration would require the producer/ importer to produce a dossier. Initiatives along the same lines as the EU REACH are also coming up in other parts of the world. REACH requires registration of at least four substances manufactured by the aluminium industry: aluminium metal, including powder, aluminium oxide, and aluminium hydroxide. The proposed legislation permits the affected companies to band together to form a consortium to develop certain aspects of the registration application. The aluminium industry has established a consortium and testing is currently underway.

Jan 1, 2006

By J. E. Gill

Introduction During the past summer, detailed geological mapping was extended to cover the entire group of 31 claims owned by Waite-Ackerman-Montgomery Mines, Ltd., and considerable new information was revealed by development and exploratory work underground. These new facts provide a more complete view of the lithology and structure of the area than has heretofore been available. They also necessitate revision of certain interpretations presented last year by Peale (l), and have served to straighten out some of the problems suggested by Porritt (2). The purpose of this paper is to outline in a broad way the relations as now understood and to discuss in detail certain points which should be of interest to members of the Institute. Maps and records by the mine staff have been freely used in arriving at the interpretation presented in the following pages. The writers are especially indebted to Mr. R. V. Porritt, the mine manager, with whom many of the problems touched upon were discussed on the ground and whose intimate knowledge of the geology of the underground workings aided greatly in testing various hypotheses. The writers have profited greatly, also, from close association with Dr. W. F. James during the course of the work. Permission to publish the included data has very kindly been given .by the management.

Jan 1, 1932

By C. R. Kato, G. Proulx

"Within the continuous scenario of reduced aluminium price and plants production costs increase, the energy consumption optimization in the aluminum electrolytic pots continues as the main focus for the producers. Energy consumption was chosen as a key performance indicator to drive the efforts and actions for improvements. Alcoa improved the energy consumption by approximately 3% from 2005 to 2015. This improvement was a result of best practices implementation, new technologies introduction, strategic actions with plant curtailments and management practices. The main objective of this paper is to highlight the importance of the management practices for planning and operational improvements beyond the technology changes. About 10 years ago, Alcoa reorganized its approach to retain knowledge in the Smelters by using a Best Practices format. For each specific subject, a skilled team defined the minimum requirements and the Best Practices for several aspects of operation and maintenance, which affect the environment, safety, cost, customers and performance. These Best Practices were deployed to all Smelters combined with training sessions to process and operation professionals. We will describe how the Best Practices were organized, the deployment strategy used, and the approach to measure the plants’ success. We will describe the management approach that includes Manufacturing Analyses focused on 3-year potential, annual planning, and weekly monitoring of plant stability. A manufacturing analysis is organized at select plants with cross-functional participation of specialists from technical, operational, procurement and finance. The output of a manufacturing analysis includes a roadmap of enablers to improve energy efficiency. A quarterly follow-up of enabler deployment is held with the plant and resources that participated in the analysis. Annually, there is a Planning Process where energy consumption enablers are selected to be implemented during the next 3 years for each plant. A monthly critical analysis is made by the plants with regional best practice support. On a weekly basis, key performance indicators are reviewed with determination of a stability index for each plant. Any deviation signal of unstable condition is alerted and supporting resources are diverted to the plant to reverse trend with countermeasures.INTRODUCTIONDue to factors like excess aluminum in the market and lower consumption in China, the LME price is declining along the last years, as showed in Figure 1. In 2011, the price peaked at US$ 2,400/ton and since then, continues to trend down and approaching the lowest level at US$ 1,500/ton in the last 5 years."

Jan 1, 2016

By S. Espley, G. Tan

"Inco's Little Stobie Mine is a low-grade nickel operation producing approximately 4()()() tons per day. Backfill has never been an economical option at the mine; therefore, the only viable type of mining in the upper zones has been by sub-level cave. This mining method allows for the draw-down of a rock cover into the empty stopes to provide stability to the over-all rock mass. In the lower areas of the mine, bulk blasthole mining methods have taken place, without rock fill, resulting in extremely large open stopes. As the mine reaches its final stage of recovery, it is inevitable that the hangingwall of the large voids will undergo tensile failure via spoiling.This paper deals with the collaborating efforts of Inco's Rock Mechanics group and the Little Stobie mining operations toward the successful recovery of the ore zone remnants such that the inevitable failure, and time of failure, of the rock mass is ""controlled"". Within the mining scheme, several key requirements had to be met to satisfy the operations: (1) production rates; (2) good blast fragmentation; and (3) secure pulling-horizons. A full-scale rock mechanics study was carried out involving: numerical modelling studies; pulling ellipse analyses; blast design, monitoring and analyses; laser profiling; and time domain rej7ectometry (TDR) instrumentation. The final recovery scheme, employing a controlled failure, involves recommendations on: (1) blasting techniques; (2) support systems; (3) mining sequences and scenarios; and (4) monitoring systems."

Jan 1, 1994

By M. D. Lawton, P. Steen

"Drilling results from the established levels at AngloRouyn Mines Limited had indicated inadequate tonnages to meet the planning schedule. It was decided to develop the main zone of the orebody below the bottom working level of the mine. The orebody dips north at an average of 50 degrees and plunges to the west at about 10 degrees. Due to the need for rapid development of this area, a decision was made to use trackless equipment.This paper describes the method used and highlights the use of small 5-ton diesel trucks as carriers for the 2-cu.yd LHD machine. The method achieved advances of about 1,000 feet per month, at a dip of 12 degrees over a length of close to 2,000 feet, using as few as 20 men per day."

Jan 1, 1971

By Botao Lin, Yan Jin, Hongjuan You, Jingjun Pan, Huiwen Pang, Mian Chen, Sen Chen

"Steam Assisted Gravity Drainage (SAGD) has become the mainstream technology for ultra-heavy oil recovery in Xinjiang oilfield, the success of which depends heavily on shortening of preheating period as well as forming homogeneous and highly permeable zone in land-facies oilsands layer. Towards this aim a special hydraulic fracturing process is required, which is accomplished through controlled water injection to a pair of horizontal wells in order to create homogenously distributed microcracks in the zone between the two wells. The associated mechanical response, however, is unclear for land-facies Karamay oilsands that is loose in texture. In this regard, this research utilizes a triaxial test system on cylindrical specimens extracted from field-collected oilsands cores. Isotropically consolidated drained triaxial compression tests are conducted on both saturated and unsaturated specimens so as to investigate the mechanical response of oilsands at different spots relative to the wellbore. Moreover, acoustic emission and fast pulse-decay permeability are performed to monitor fracture development and permeability evolution. Based on these experimental studies, the mechanism of dilation in oilsands is comprehensively analyzed. The findings reveal distinctive behavior between the saturated and unsaturated specimens as respect to dilation, porosity/volumetric evolution and change of permeability. It is also found that shear bands can be created upon shearing on triaxial specimens, rendering porosity or volumetric strain the factor that is more proper for evaluation of stimulation efficiency in the field.INTRODUCTIONXinjiang oilfield is widely known for its abundant deposit of heavy and ultra-heavy oil that has been estimated to be several hundred million tons. The ultra-heavy oil deposit located in Fengcheng region of Karamay at the northwestern part of the Junggar Basin, Xinjiang, China, has over 360 million tons of resource (Yuan et al. 2013). The resource is deposited in depths from 180 to 450 m and has viscosity over 100, 000 mPa•s at a temperature of 50ºC, bringing technical challenges to recovery activities."

Jan 1, 2015

By B. Ignasiak

Laboratory studies suggest that improvements of coke strength brought about by pre-heating caking coals before carbonization accrue from inadvertent oxidation rather than from other low-temperature changes in the coal mass. Controlled oxidation of highly caking coal, followed by laboratory carbonization, produces cokes which, in terms of a laboratory scale tumble test index, are equivalent to those obtained from prime metallurgical blends. Appropriately formulated blends of exhaustively oxidized and fresh caking coal similarly yield cokes with strength indices comparable to those of cokes made from the same coal after oxidation under optimum conditions.

Jan 1, 1979

By M. Hardy

"The structural design of mine headframes is challenging due to the significant differences in the geometry, rigidity, and behaviour of these structures compared to conventional buildings. The differences are related to the main purpose of these structures, which is not human occupancy, but rather the support of hoisting equipment. The main objective of this paper is to present the seismic elastic behaviour of headframe structures in comparison with conventional buildings, which is the base case for the definition of seismic loads. This paper highlights the impact of backlegs on the dynamic behaviour of mine headframes, more specifically the resulting torsional sensitivity. INTRODUCTION The design of industrial structures is often governed by industrial processes rather than by architectural constraints. In ground-mounted hoisting plants, the structural configuration of headframes must allow clearances around conveyances and ropes while resisting the lateral loads associated with the hoisting equipment. Typically, these structures use backlegs to withstand the lateral loads, which leads to highly irregular structures with unconventional dynamic behaviour. The codes and standards applicable to the structural design of mine headframes in Canada are often incomplete or not adapted to the reality of practising engineers. This situation creates confusion, and engineers must look at various guidelines and international standards to support the engineering calculations required for the design of these structures. The loads resulting from the support of hoisting equipment, such as ropes and conveyances, are usually simple to calculate and are determined based on the information from manufacturer and industry related guidelines. Moreover, the loads associated with snow accumulation and wind are calculated applying the same methodology used for conventional buildings, without any major issues. On the other hand, the seismic loads are often difficult to calculate based on the methodology from the National Building Code of Canada due to the significant differences in the dynamic behaviour of the structures. The resulting structures may be either over-designed or worse, under-designed. Hence, there is a lack of uniformity in engineers’ designs. The latest edition of CSA S16-14 “Design of steel structures” includes Annex M (Informative) “Seismic design of industrial steel structures” to help designers close the gap between the requirements of traditional regulations and actual engineering practice."

Jan 1, 2019

By Charles Camsell

At the Annual General Meeting of the Institute in 1924. I endeavoured to present the position held by the mineral industries in the commercial life of this country. The facts and figures were presented at that time in a detached way. Since then, however, I have made some attempt to analyze them in order to determine the causes for that position and to draw some conclusions as to the future of the mining industry. As everyone knows, our trade figures are very often used in political discussion, especially in discussion of tariff policy. It would be entirely out of order for me to say anything touching the tariff issue and I want to have it clearly understood that, in my opinion, the material I am about to present contains not a single statement or conclusion which anyone would be warranted in using as an argument for either a lower or a higher tariff or for tariff changes of any kind. As a starting point, let me re-state, very sketchily, Canada's general situation in external trade. In the last calendar year, 1924, we sold Canadian merchandise of all kinds to other countries to the value of $1,045,000,000 in round figures. Our purchases abroad reached about $893,000,000. Thus our sales exceeded our purchases by roughly $152,000,000. In other words, we had what is known as a 'favourable balance of trade' - one of the biggest favourable balances we have ever had in our history. The proceeds of our sales of Canadian products enabled us to meet the bills for all our purchases of foreign commodities and, in addition, placed a large surplus to our credit with which to offset our interest charges and other obligations abroad.

Jan 1, 1925

By G. H. Blackwell, N. I. Norrish

"At most operating mines, geostatistical are reserve estimation methods have been implemented by head office or consulting groups . With recent advances in small computer technology it is now possible for a remotely-located mine department to independently implement a geostatistical package.This paper describes the evolution of geostatistical routines to calculate the mineral inventory for porphyry type copper/ molybdenum or similar are bodies. The problems encountered in down sizing the geostatistical routines to run using limited minesite computing facilities are discussed. The high quality of the results, in spite of some compromises to geostatistical theory, is emphasized.The first stage entailed the development of a mineral inventory based on diamond drill data. The difficulties in fitting variogram models to two metals, copper and molybdenum, and the shortcomings of the mineral inventory due to the mixing of lesser quality exploration data with data from more recent diamond drilling are discussed.To improve the ore reserve estimates for short-term planning, a mineral inventory was produced using both the diamond drill and production blast hole drilling data. This inventory, when compared to actual grades, was found to be quite satisfactory for short-term planning. The inventory also provided a reliable data base for long range pit design and financial planning. By regularly updating the mineral inventory, many of the uncertainties of mining a low-grade orebody were minimizedIntroductionThe comparatively low grades of many Canadian mineral deposit s, the escalation of mine operating costs, and the volatility of metal prices in recent years, has required improvements to both short- and long-term mine planning.One of the prerequisites to improved planning systems is the need for accurate grade prediction. This paper describes the on-site implementation of geostatistical techniques for grade estimation of a porphyry I vein type copper/molybdenum ore body ."

Jan 1, 1987

By N. C. Carter, Wm. H. White, J. E. Harakal

"Of twenty-one ore deposits in British Columbia which are either in production or advanced stages of exploration, five have potassium-argon ages in a range of 165-205 m.y., eight are in a range of 44-55 m.y. and the remainder are either ca. 140 m.y. or ca. 100 m.y. old. Deposits of the oldest group have generally similar geological environments and radiometrically indistinguishable ages of magmatic and hydrothermal minerals. Deposits of the youngest group also have similar geological environments, with successive magmatic and hydrothermal events closely intermingled in time and place. Such deposits find no comfortable home in existing classifications of ore deposits. 1t is suggested, therefore, that those epigenetic deposits which can be shown by radiometrie and/or geologie means to be coeval with genetically related magmatism be designated as ""paramagmatic deposits."""

Jan 1, 1968

By P. K. Kaiser, S. M. Maloney, S. P. Singh

"Corrosion of underground support measures constitutes a concern to industry in both safety and economic terms. It also represents a potential market for corrosion resistant materials such as stainless steel.In order to assess the market potential for a stainless steel friction rock bolt, a review of current corrosion processes and remedial or preventative measures in the underground environment was undertaken. This was supplemented by distribution to industry of a detailed questionnaire, concerning the magnitude and extent of support corrosion and the costs of current support measures, and by visits to selected sites. Following data synthesis, support costs were established and the economic benefit of stainless steel rock bolts evaluated.Stainless steel rock bolts can be an effective cost reducing measure in unscreened areas requiring frequent reconditioning. Their benefit is rapidly diminished, however, if only partial reconditioning is required, the reconditioning interval is long or if screening is required.While most industry personnel are receptive to the application of stainless steel support measures, the localization of corrosion problems and the potential high cost of this type of support are barriers to its widespread implementation. They have potential for use in extreme environments. However, this relatively small market may not be economically viable.IntroductionFriction rock bolts are the simplest of all interior rock fixtures. The friction resistance to sliding of the rock on the bolt is generated by a radial pressure against the borehole wall over the length of the bolt. Two types of friction rock bolts are currently marketed, the Split Set and the Swellex.Unlike conventional point anchor bolts, friction rock stabilizers may move relative to the rock strata and maintain their capacity even if rock shifts, a condition that sometimes loosens or breaks conventional bolts. Ease of installation, effectiveness in jointed as well as weaker rock, and the possibility of having relatively long bolts are a few of the many advantages which generate considerable interest in the application of friction rock bolts (Wijk and Skogberg, 1982). However, due to their thin-walled construction and large surface area, frictional rock stabilizers are more susceptible than conventional bolts to damage by corrosion. For this reason, they are normally not recommended for long-term use (Jolly and Neumeier, 1987).In light of the above discussion; the Nickel Development Institute commissioned a study by the Geomechanics Research Centre with the objective of generating a credible database for the assessment of the feasibility of a stainless steel friction bolt system in corrosive ground and mine environments."

Jan 1, 1990

The negative effects of pyrite and pyrrhotite on thiosulfate gold leaching have been investigated. Possible remedies to reduce some problems are discussed. In a gold bearing pure silicate ore, 92% of gold could be extracted within 3 hours using a solution containing 0.2 mol/L ammonium thiosulfate, 0.9 mol/L ammonia, 30 - 300 ppm copper sulfate and 8.6 ppm dissolved oxygen at pH 10.26. The thiosulfate consumption was 7.1 kg/t under these conditions and could be further reduced to 3.5 kg/t by decreasing the dissolved oxygen to 0.3 ppm. Addition of 16% pyrrhotite or pyrite into the silicate slurry led to a decrease in gold extraction by 2% or 9% respectively and an increase of thiosulfate consumption by 11 kg/t or12.8 kg/t respectively in three hours. Several adjustments, such as increasing copper ion and ammonia concentration and reducing the dissolved oxygen level to 0.3 ppm resulted in increased gold extraction and lower thiosulfate consumption despite the presence of these sulfides.

Jan 1, 2005

By K. Izumi

Ultra-grain refinement and high strengthening of metals by accumulative roll bonding (ARB) was widely reported. However, applications of ARB to magnesium alloys were rather limited. In this study, Mg-9%Li-1%Y sheets were applied to ARB at room temperature. Six 0.5 mm thick sheets were stacked and reduced into 0.5 mm thick by four passes. The procedure was repeated up to three cycles, so that the equivalent strain of 6.2 was applied. The sheets show dual phase structure with a (hcp) and ß (bcc). Grains elongates to the rolling direction with increasing number of ARB cycles. After three cycles, fragmented a grains with average size of about 300 nm are uniformly distributed. After the first cycle, the ultimate tensile strength increases to 180 MPa from 133 MPa, while the elongation decreases, however, still high (26%). The tensile strength slightly decreases by the second cycle and does not change at the third cycle. Meanwhile the elongation increases by the second cycle and the sheets show 41% of the elongation after the third cycle.

Jan 1, 2006

By C. R. Stelck

"AbstractThe Cardium formation of northeastern British •Columbia •contains an erosional unconformity that becomes progressively more severe northward until, •at Liard river, the stratigraphic hiatus eliminates the underlying Lower •Cardium sandstone, the Kaskapau formation, and the upper Dunvegan sandstones. The area of unconformity roughly coincides with the distribution of the continental facies of the earlier Dunvegan formation. Along Wapiti river, the zone fossil Scaphites ventricosus Meek and Hayden is found in the Bad-heart member of the overlying Wapiabi shale; Scaphites :preventricosus. Cobban marks the base of the Wapiabi shale; Scaphites cf. corvensis •Cobban is found in the middle shale member of the •Cardium formation. The log of the Red-Willow No. 1 well shows close similarity to the outcrop sections south of Wapiti river. The Cardium formation is mainly late Turonian in age. Two other pre-Cardium Turonian sands of north-eastern British Columbia are named the Wartenbe and Tuskoola sands.IntroductionTHE Upper Cretaceous Cardium (Bighorn) sandstone formation of the Foothills of northeastern British Columbia carries within its formational limits an erosional unconformity. The unconformity decreases to the southeast, becoming in immediate shoreline regions, now under the plains, a minor diastem. Such diastems, or stratigraphic intervals of non-deposition, occurring in the shallow unda-zone are paralleled in the deeper portions of the unda-zone by the phenomena of sub-aqueous winnowing. '.This winnowing and re-working •at critical depths creates sand areas with porosity."

Jan 1, 1955