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By S. I. Saif

The Key Anacon deposit lies about 6 miles northeast of the Brunswick NO.6 mine of Brunswick Mining and Smelting Corporation. Geological mapping, especially in the well-exposed Nepisiguit River section, geophysical data, and information from extensive underground and some surface drilling show that the rocks at Key Anacon are similar in many aspects of stratigraphy and structure to those of the Brunswick Mine area. They include narrow beds of fine acid volcanic material interpreted to be metatuff and volcanogenic metasediments. The massive sulphide ore body at Key Anacon lies immediately above these acidic rocks, in association with other chloritic, sideritic or magnetic iron-rich metasediments. The iron formation, which is similar to that associated with other orebodies in the district, is overlain by massive andesitic material. Four phases of structural deformation have been recognized in the Key Anacon area; they are similar in intensity and style to those of the Brunswick No. 6 mine area. The orebody lies in a zone of complex isoclinal folding along the flank of a major F2 fold (Key Anacon Syncline) and in general appears to be stratiform. The ore occurs in probable F2 parasitic folds, and this suggests a complicated structural geometry superimposed on the original beds. The general similarity of the mineralization at Key Anacon, together with its occurrence with other iron-rich metasediments between a footwall of acid volcanic material and overlying andesitic rocks, is suggestive of stratigraphic time-equivalence with the Brunswick zone . If so, the metavolcanics at Key Anacon might have been derived either from a center within the main volcanic pile to the west or from a smaller local center active at the same time. Alternatively, the Key Anacon ore could have been formed during a much older volcanic cycle. The solution to this aspect of the problem is the subject of a continuing study.

Jan 1, 1978

By Mark Freberg

"IntroductionThis chapter is intended to provide information on the operation and maintenance of several pieces of equipment used in heavy media separation. Most heavy media separation circuits, particularly those involving bath separators can be considered as high maintenance areas. Because of this the efficient operation and maintenance of these circuits is very important if the cost per ton of material treated is to be kept to an acceptable level.Heavy media separation (HMS), is a process used to separate particles of different specific gravities. Under laboratory conditions the ideal way to separate two types of particles which have different specific gravities is to suspend them in a heavy liquid which has a specific gravity between those of the two types of particles. Those particles with the lower specific gravities will float on top of the liquid while the higher specific gravity material will sink to the bottom. Given enough time and a sufficient volume of heavy liquid this process will be essentially insensitive to the sizes of the particles involved.Heavy media separation circuits make use of the same principles described above. The material to be treated is introduced into a mixture of finely ground solids, called media, and water which takes the place of the heavy liquid; the mixture of solids and water is known as medium. The separating force can be either gravity or centrifugal force. The type of solids used as media varies but it is usually a high specific gravity material such as magnetite, galena or ferrosilicon.Heavy media separation is used extensively in the cleaning of coal and to a lesser extent as a preconcentration step in base metal and iron ore operations."

Jan 1, 1989

By A. Osouli, B. Moradi Bajestani

"Increase in permeability of rock mass is vital for both petroleum and geothermal applications. Hydraulic fracturing is a common method to create and increase the permeability for production. Due to the complexity of fracture propagation in a naturally fractured medium, understanding the interaction between hydraulic fracture (HF) and natural fracture (NF) is of great importance to optimize the fracturing process. The possibility of interaction between HF and NF is partly a function of orientation. Various scenarios are predictable for hydraulic fracture regarding the intersection with NF such as being arrested by NF, crossing NF or crossing the fissure while injecting water into it. Different parameters such as geomechanical and geometrical properties of surrounding rock mass, the operational parameters such as injection rate and the angle between created hydraulic fracture and natural fracture (approach angle) can affect the result of hydraulic fracture and natural fracture intersection. In this paper, using a series of flow-coupled Distinct Fracture Network (DFN) simulations, hydraulic fractures were analyzed to investigate the influence of the aforementioned parameters on the hydraulic fracture propagating. Results show that the most significant parameters affecting the interaction of natural and hydraulic fracture are orientation of the intersection as well as injection rate. The interaction and fracture propagation in NF and HF intersections are also studied and discussed in detail.INTRODUCTIONThe hydraulic fracture technology has substantially changed the oil, gas and geothermal industries. With the help of this technology, extraction of fossil resources from tight shale reservoirs will be economical, feasible and sustainable. Due to presence of massive oil and gas trapped in these reservoirs, this technology has been the center of attention for the past 40 years (King, 2012). Hydraulic fracturing is the process in which high pressure water is pumped into shale unconventional reservoirs with low to ultralow permeabilities. With this process paths are created in these mediums for delivering oil and gas to horizontal wellbore and increase the surrounding rock medium permeability. Economical and sustainable stimulation of these tight reservoirs is highly dependable on our understanding in regard to fracture propagation in the highly complex rock medium. Hydraulic fracturing process in rock mediums with preexisting natural fractures is more complex because of the high possibility of Hydraulic Fracture (HF) being arrested or deviated by Natural Fracture (NF). Also, HF and NF intersection can influence the required pumping pressure, injection rate, the outcome of horizontal wellbore and the affected geological underground zones. Since the 1950s, numerous studies have been conducted to predict and plan fracture propagation with the help of modeling and simulation methods. Having a thorough and accurate prediction of fracturing process will not only prevent stimulation of unwanted geological zones or pollution of aquifers, but also will improve the efficiency of the fracturing process. Previously, several studies have been conducted in order to investigate and analyze the interaction of hydraulic fracture and natural fracture (Cottrell, Hosseinpour, & Dershowitz, 2013; Doe, Lacazette, Dershowitz, & Knitter, 2013; Shakib, 2013; Zhang & Jeffrey, 2006)."

Jan 1, 2015

By S. B. Mishra

Ni-20Cr metallic coating was deposited on a Ni-based Superalloy (3Fe-19.5Cr¬0.3Ti-Balance Ni) by a shrouded plasma spray process; NiCrA1Y was used as a bond coat. Erosion studies were conducted on uncoated and plasma-spray coated superalloy specimens using an air-jet erosion test rig at a velocity of 40 m/s and impingement angles of 30° and 90°. The coating has been characterized for porosity, microhardness and microstructure and X-Ray Diffraction (XRD). An electron probe micro analyzer (EPMA) was used to obtain X-ray elemental mappings of the coating along the cross-section. Scanning electron microscope (SEM) with EDAX attachment was used to analyze the eroded surfaces.

Jan 1, 2005

By John L. Rich

A New Field for the Mining Industry A new field for the mining industry is in prospect. This is the recovery of the petroleum which has been left in the ground in the older oil fields whose yield has declined until they are no longer profitable to operate in the ordinary way. The fact that an oil field has reached the economic limit for operation by pumping does not necessarily 'mean that the oil has ? been exhausted. In many such cases not over one-fifth, or even one-tenth, of the total oil content of the field may have been taken out when this stage has been reached. This means that there exists a large reserve of oil which can be recovered by whatever process best takes advantage of the natural conditions under which the oil occurs. Mine drainage is one of the processes by which this oil may be recovered. Its relative importance will depend partly on the ingenuity and wide-awakeness of mining engineers, and on mining capital. The opportunity is undoubtedly at hand. In order that we may be in a position to judge the possible advantages of mining methods for the recovery of this oil, I have reviewed, on the following pages, the methods now in use, and have discussed the physical conditions of the reservoir rocks in which the oil is found, and the suitability of the various recovery processes, in use or proposed, in the light of these reservoir conditions.

Jan 1, 1927

By Michael Sudbury

Introduction The essence of a good presentation is said to be: Outline what you are going to say Say it Summarize what you said This is perhaps especially good advice at 8.30 a.m. So here goes: This is an attempt to put numbers on three inextricably linked subjects: People and the Future Irrigation and Agriculture Mine Water and Mine Waste

May 1, 2013

By K. N. Karparov

?Two highwall failures in a South African coal mine defied analysis by widely accepted limit equilibrium methods. ?The geological conditions were complex, with undulating coal-bearing strata overlying a karstic topography formed in underlying dolomite belonging to the Transvaal Supergroup. ?It was clear that the simplifying assumptions made by all limit equilibrium methods were inappropriate in the conditions.

May 1, 2007

By D. Milne

Laser profilometers exist for obtaining very accurate two and three dimensional profiles of joint surfaces. The application of this technology is not commonly applied to the collection of field data on discontinuity surface roughness. Rugged and portable field devices are not commonly used and the value of the possible field data that can be collected has not been well recognised. This paper reviews commonly used field techniques for assessing discontinuity roughness, discusses the value of this data and presents a new laser profilometer design for field application.

May 1, 2009

By João Felipe Costa, Jair Carlos Koppe, André C. Zingano

Abstract - Traditional mine planning based on block models built with interpolation techniques such as kriging does not take into account the uncertainty associated with the estimates. These models are inadequate for short-range mine planning. In contrast, conditionally simulated models reproduce the actual variability (histogram) and spatial continuity (variogram) of the attributes of interest. Conditional simulation can be used to address the problem of measuring the uncertainty associated with an estimate. This paper outlines how the sequential Gaussian conditional simulation algorithm can be used to assess uncertainty of grade estimates and also illustrates how simulated models can be incorporated into mine planning and scheduling. A case study demonstrates the efficiency of the method in assessing risk associated with geological and engineering variables.

Jan 1, 2000

By José Carlos Marques

This paper addresses recent calls to study the role of the state in private regulation. Using an historical, organizational-field approach, I trace and explain the evolution of public debates and interaction of different forms of regulatory initiatives dealing with Canada?s mining industry. The empirical evidence presented calls attention to the interaction amongst different regulatory forms, as well as the conditions under which the state will encourage fragmented initiatives, rather than facilitate and catalyze regulatory strengthening and consolidation. As such, my analysis: problematizes the underlying assumptions used as a starting point by the growing literature on the role of the state in private regulation; connects and juxtaposes recent scholarship to more established literature on regulatory state failure and self-regulation. I also contribute to the discussion on Canada?s CSR policy, outlining the likely regulatory effects of the current policy framework.

Aug 1, 2013

By Jörgen Appelgren

Atlas Copco, a leading supplier of equipment and services to the mining and construction industries, is consistently pursuing its strategy to offer the most productive and economical solutions by continuously offering new innovative products. These are in most cases developed and tested in close cooperation with demanding end users before being officially launched on the international market. The demands for higher productivity and improved overall economy have resulted in systems for automation of the drilling cycle and also tools for integrating the Drilling equipment to the production control system used by the customer. In terms of improving the blasted material quality, Atlas Copco has placed emphasis on hole straightness and the need for hole logging and positioning. By applying state of the art technology to today?s computerized drilling rigs, major steps in improving overall drilling and blasting performance have been achieved. This paper will give some examples derived from the latest development of solutions for the Rotary drilling product line.

Oct 1, 2009

By W. Dan Hausel

"Abstract-Hundreds of diamonds have been found in the United States. The majority of the discoveries occurred during the 19th century as a by-product of placer gold mining. Most of these early diamond finds have no known source, and in many cases are situated in areas unfavorable for diamond exploration based on current models that require kimberlite or lamproite to be emplaced in a stable Archean craton or Proterozoic craton margin.Diamonds have also been recovered in situ from lamproite at Murfreesburo, Arkansas, from kimberlite in the Lake Ellen region of Michigan, and in several kimberlites in the Colorado-Wyoming State Line district. Unverified reports also suggest that diamonds may have been recovered from other related intrusions at a number of localities in the United States."

Jan 1, 1995

By David Dreisinger

Arsenic occurs in nature in association with many valuable metals including copper, nickel, cobalt, gold and platinum group metals. The recovery of these valuable metals is of course complicated by the need to extract and stabilize arsenic in a form suitable for disposal. In this paper, a review of some recent developments related to hydrometallurgical treatment of arsenic bearing materials is provided. The key aspects of metal dissolution, arsenic stabilization and disposal are discussed.

Jan 1, 2014

By Lisa J. Renaud

For generations, the mining industry has been committed to work toward developing new technology that can improve safety and increase production. Now with a more environmentally conscious society and tighter environmental regulations, a natural progression for the industry is to develop and take-on ?green? or environmentally friendly technologies. Not only could this improve the sustainability of operations, but could also reduce the long-term environmental impact footprint that is left behind. Algae represent a new frontier in research and development. As discussed specifically in this paper, algae, specifically microalgae, can be used for the production of biodiesel and other green chemicals by exploiting carbon dioxide and waste heat contained within process off-gasses. The potential positive benefits of this approach in terms of contribution to community and the environment are significant, and the focus of our research and development on microalgae production technology.

Oct 1, 2010

By Neil Westoll

Extensive Global Network ?Working together, AECOM provides clients with a unique blend of global reach, local knowledge, innovation and technical excellence. ?43,000+ team members worldwide ?450+ offices ?100+ countries ?6 continents The Changing Climate ?Climate change is ?official??IPCC 2007 ?Climate change will create instability, change and opportunities ?Companies that are resilient and adapt will survive and evolve ?CO2/GHG emissions will be curbed by legislation ?How will this affect the mining industry? ?How can the mining industry adapt to the new realities?

May 1, 2009

The PEMAC Commitment to World Class Industry in Canada The Plant Engineering and Maintenance Association of Canada PEMAC is a national, not-for-profit industry and technical association for plant and facility maintenance, engineering and physical asset management practitioners and professionals. Founded mid 80?s in the last century PEMAC is a knowledge based organization that focuses on sharing knowledge with our members and the profession. We provide education and professional development programs and certification for maintenance practitioners and professionals. We develop, produce and participate in conferences, seminars and trade shows.

May 1, 2008

By J. W. Merks

"The accuracy of a measurement on minerals and ores can be assured by applying suitable and unbiased procedures but its precision is a function of the number of primary increments and their mass, the number of lots per consignment or samples per shift, and the number of measurements on analysis fine samples.Experimental data will be used to show how the variance components for sampling, sample preparation and analysis contribute to the total variance on which precision statements for the final measurement are based. This type of experiment should not only form part of quality control programs at mines and smelters, but also underly the criteria on which the design of manual sampling regimes and mechanical sampling systems for bulk solids and slurries should be based.Sampling systems and regimes can only be adjusted and optimized if the variance component for each step in a quality evaluation process is measured. Knowledge of precision characteristics lies at the core of effective loss prevention and control programs."

Jan 1, 1985

By T. I. Kunkel

The economic prosperity of many Canadian communities depends on resource extraction within the traditional territories of Indigenous people. The geographic sites where these resources are situated are also areas where these Indigenous people have sustained themselves for millennia through hunting, fishing, trapping, and gathering activities. These traditional activities provide not only sustenance, but also cultural and spiritual values, and the ability to transmit oral Indigenous cultures and customs from generation to generation. The multimillion dollar revenue mine project proposed within the Cariboo Chilcotin region of British Columbia is situated geographically in a location which has sustained the Tsilhqot?in people for millennia. However, this group of people have important social and cultural values nested within the traditional activities at this location. These values are typically not at the forefront of resource development. Using Indigenous research and grounded theory, this research paper briefly outlines Aboriginal values of the First Nations communities within the Cariboo Chilcotin region and some lessons learned from the Tsilhqot?in people during the environmental assessment of the mine proposal.

Aug 1, 2013

By Yan Jie

The oxygen-enriched bottom-blowing continuous converting process for copper matte was recently developed by the China-ENFI Engineering Corporation. The first commercial plant based on this technology was successfully commissioned at the Yuguang smelter in China in March 2014. The present paper describes this new continuous converting process and compares technical characteristics with other continuous converting processes including: Kennecott-Outokumpu flash converting, the Mitsubishi Process, the Noranda Converter and TSL continuous converting. The bottom-blowing oxygenated continuous converter with competitive capex and opex costs is seen as an attractive alternative to the Peirce-Smith converter.

Jan 1, 2014

By Alessandro Navarra

Discrete event simulation provides a computational framework in which the use of smelting equipment can be analyzed and optimized, leading to the development of alternative modes of operation. Much of the complexity of copper and nickel smelters is centered on the converter aisle. These converters operate in parallel, produce batches, and set the tempo for the downstream operations. In practice, smelter staff schedule daily operations to coordinate the smelting furnaces and converters with downstream operations. Thus, a realistic simulation of smelter operations, over hundreds of days, should incorporate converter scheduling algorithms as presented in this paper.

Jan 1, 2014