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By Julver Álvarez

El presente trabajo describe el comportamiento estructural y mineralización del estaño-cobre en la mina San Rafael, Puno. En este sentido, las pizarras de la formación Sandia del Ordovisco Superior, por metamorfismo de contacto con el intrusivo, han sido transformadas a hornfels, que junto a las cuarcitas se presentan algunas veces como una cubierta superficial sobre el intrusivo. Asimismo, los intrusivos y las pizarras son favorables para la mineralización de estaño, aunque los cuerpos del mineral son más definidos y persistentes en el intrusivo.

Sep 13, 2001

By D. J. Leidel

The offshore production of oil and gas resources has been active in the Gulf of Mexico since Kerr- McGee drilled the first commercial well out of the sight of land in 1947. Since then, approximately 60% of the offshore oil/gas production structures used globally have been erected in the GOM to support the production of energy resources’. The shallow, shelf and shelf edge waters of the Gulf of Mexico have reached or are rapidly approaching production maturity, requiring that the fixed structures used to support energy production be removed or otherwise disposed of by suitable means. The use of energetic materials has been determined to be a safe, efficient and cost effective technology to remove fixed offshore structures whose service life has been exceeded.

Jan 1, 2002

By Gualberto Salas

Dado que la voladura es una de las operaciones unitarias de mayor extracción del mineral -en tanto logra una adecuada fragmentación de la roca con un costo reducido, es necesario lograr una interrelación entre los resultados de la voladura y el de las operaciones unitarias como herramientas que evalúan y optimizan los diseños de los disparos. En ese sentido, el presente trabajo describe las técnicas para el diseño de las mallas de perforación, los programas para la simulación de la voladura y también para medir los resultados, que permitirán realizar los ajustes necesarios para mejorar los resultados de fragmentación y reducir el costo de operación de minado.

Sep 13, 2001

By Hannan J. C

In New South Wales, development applications for major coal mining proposals are determined by the Minister for Planning and Environment and applications for mining leases and other mineral titles are dealt with by the Minister for Mineral Resources. The environmental conditions placed on the development consent, the coal mining lease and the approvals and licences under the pollution control legislation, amount to a substantial component of any new project's planning and commissioning considerations.An outline is presented of the framework within which various approvals are granted and conditions for environmental management are imposed upon mining projects. The principles and concerns, as perceived by the regulatory authorities, on which the majority of approval conditions are based are also outlined.No attempt has been made to analyse the extent to which these principles or standards are achieved in practice, nor to discuss the degree to which some of the conditions are achievable with the current status of technology and economics in the coal industry.

Jan 1, 1987

By T A. J Hopper, B J. Birt, K K. Trofimczyk

Nuclear magnetic resonance (NMR) has been utilised in the oil and gas industry for over 60 years. The technology was recently identified as having potential value in iron ore, where latent bound moisture may affect ore handling even after dewatering and extraction. The first step in introducing this technology to iron ore involved laboratory tests on drill core samples. These results established the parameters for a downhole borehole magnetic resonance (BMR) tool for iron-rich environments, which was subsequently developed. A major challenge involved shrinking what is a very large tool in the oil industry to a slimhole, lightweight, 1-man deployable mining tool.Of primary concern was the ability to measure the very fast transverse relaxation times (T2s) seen in the lab results on iron ore samples. Iron creates local field gradients that significantly decrease the T2 times. As a result, the BMR tool had to be able to measure T2s in the range of hundreds of microseconds, a level not required in clastic sedimentary formations. The choice of T2 cut-offs in iron ore is critical to successfully separating the free and bound fluids. The industry has typically focused on T2 cut-offs in clastics and carbonates, but not in systems with high iron content. Using core analysis results (poro-perm and NMR) we were able to verify the BMR response. The T2 cut-offs were determined from NMR core analysis and then applied to the logs so as to provide a continuous, calibrated permeability log.Field results that highlight the challenge involved in logging in iron-rich environments are presented, as well as some minimum requirements for a successful BMR log. Examples from boreholes in an active iron ore mine in the Pilbara iron ore province in Western Australia are presented, as well as explanations for how NMR data can be combined with bulk density logs to provide a continuous dry weight density log based on the original density-porosity equation from Alger et al (1963).CITATION:Hopper, T A J, Trofimczyk, K K and Birt, B J, 2017. Development of a slimhole downhole nuclear magnetic resonance tool for iron ore – some applications and limitations, in Proceedings Iron Ore 2017, pp 473–480 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017

By P. A. Dimas

A new family of sulfide flotation collectors has been developed in our laboratory. These formulations are comprised of novel renewable materials combined with conventional reagents. The resulting diversity permits tunability of collector chemistry to meet a range of flotation problems. Several attributes of the new collectors are presented.

Jan 1, 2012

For a large scale open pit mining and concentrating operation, on a low-grade disseminated ore body, it is possible to set an approximate lower bound on economically feasible operating scales and an approximate upper bound on economically desirable scales in a relatively straight forward manner. The optimum scale ofplanned operations, with respect to the objective ofmaximisation ofthe net value ofthe orebody, will have to be arrived at by iterative planning runs, but it may be expected to lie close to this upper bound. The effects of infrastructural costs and of the addition of a risk premium to the cost of capital, to form the discount rate for planning purposes, are considered theoretically and by worked example. It is concluded that a perceived special, unsystematic, risk should not be accounted for by the use of such a risk premium as this is inducive to placing a greater amount of investment capital at risk, for no greater return-rate to investment.

Jan 1, 1986

By J. Moskowitz

Construction of the new JFK International Airport Light Rail System (LRS) began in 1998 with a pre-construction load test program. This $1.2 billion design-build project consists of approximately 13 kilometers of elevated twin rail. The elevated rail system is supported on nearly 500 piers requiring deep foundations. The presence of underlying compressible and liquefiable soils as well as space constraints precluded the use of large spread footings. In the 1980's the Port Authority undertook extensive testing to evaluate various piles and drilled shafts types. The LRS piling sub-contractor and the Geotechnical Engineer conducted additional tests for this project to identify the most cost effective deep foundation type. Candidate piles types included: Monotube®, Tapertube®, and closed ended pipe piles. The tapered pile types were found to be the most cost effective and the project utilized both the Monotube® and Tapertube® piles. This paper presents the results of the load test program and the issues related to pile driving induced vibrations and ground movement.

Jan 1, 2000

By K. Lang

A case study is provided that highlights the successful use of high efficiency electrical submersible pumps (ESPs) adapted from the oil and gas industry for a large scale, open pit mine dewatering operation. In this case, the mine is Goldcorp?s Peñasquito Mine, Peñasco and Chile Colorado open pit development areas in Zacatecas, Mexico. At the time of publication (July 2012), there were 18 vertical bedrock dewatering wells producing an average flow rate of 350 liters per second (lps) from the Peñasco and Chile Colorado development areas. Average pumping rate per well was 18 lps, with a maximum of 44 lps. The depth of wells varies from 330 m to 500m, and includes both in-pit and perimeter (ex-pit) pumping centers. A network of 50 piezometers was used to monitor the response of groundwater levels to pumping. Since dewatering operations were initiated in 2007, groundwater elevations decreased overall, from approximately 1950 m above sea level (masl) to around 1625 masl, for a total of 340 m of drawdown. The pit floor elevation was approximately 1655 masl. All of the producing wells were constructed with 16-inch boreholes, completed with 10-inch diameter blank casing and louvered screen sections and equipped with ESPs. The application of ESPs has proven to be highly effective in the case of Peñasquito?s dewatering operations. Noted advantages include the following: ? Small diameter pump allows use of smaller diameter boreholes (16 inches) and casing / screens (10 inches) reducing well drilling and construction costs ? Greater application range for flow rate and total dynamic head ? Variable speed drive systems for greater energy efficiency and flow rate optimization ? Integration of downhole instrumentation into the motor and pump assembly The advantages and benefits of using high efficiency ESPs revolutionized the dewatering program at Peñasquito open pit mine as evidenced by the number of deep vertical well installations and high dewatering flow rates and total dynamic head requirements.

Feb 27, 2013

The mining industry has recognised for some time the importance of supporting programs which serve to educate the Australian public about the socio-economic benefits of mineral resource development. More recently, industry leaders have realised that the future development of the industry will depend on attracting sufficient young people to commit to a career in the industry. Apart from lending support to the traditional education institutions in Australia, the industry now has the opportunity to participate in the development of education programs in museums. Whilst historic, mining-related theme parks such as Sovereign Hill and Coal Creek in Victoria serve very effectively the objective of relating past mining activities to the socio-economic development of Australia, there still exists the need to provide a facility which, under the same roof, excites interest in geology, mining, mineral processing and the role of minerals and energy in modern society. The redeveloped Geological and Mining Museum (the "Mining Museum"), which is located in The Rocks area of Sydney, meets this objective. With the central themes of formation and transformation this new Museum, which aims to be the best of its type in the world, will use modern museum exhibit techniques and the resources of the Minerals and Energy Information Centre to educate the community including teachers and school children. In the best tradition of museums, outstanding mineral and other collections will complement a comprehensive range of interactive, high technology exhibits which will include a number of exploratory "hands on" facilities. Australian companies are joining with Government to fund this exciting new museum. There is still a need for industry professionals to realise that a modern "mining" museum is no longer just a repository for objects of mining heritage but is also an important centre which serves as an important educational and public relations interface. The Education Section of the new "Mining Museum", which is linked closely with the new Minerals and Energy Information Centre, will be working closely with appropriate mining-related Tertiary institutions to develop specific career programs aimed at secondary students who wish to pursue a career in the mineral resource industries.

Jan 1, 1989

By F. E. du Plessis

"The distinction between data suitable for process control and data subject to aliasing only becomes quantifiable with the availability of rapid real-time measurements. Expecting the dynamics of flotation to vary for different ore types, process flows and equipment types; a study was conducted to compare the dynamics of different flotation processes. The results shed light on the critical sampling intervals required for process control which in turn allows process stabilization and optimization. The technology used for the in-line measurements is based on diffuse reflective spectroscopy and has been introduced into the mineral processing industry over the past ten years. It has been widely implemented in the sulphide flotation industry in South Africa for the real-time measurement of grade.BACKGROUND AND OBJECTIVE A study was conducted by Du Plessis and Keet (2010) to quantify the minimum sample frequency required for grade and/or impurity control. The study was based on chromite data collected at 15 second intervals from the concentrate line of a flash float cell in the Platinum industry. The data captured the natural process variation of the entrained chromite through water recovery due to changes in feed parameters and flotation performance. It was found that the minimum rate of sampling required from the studied flash float concentrate was 2 minutes. This sampling interval time accounted for 90% of the variance in the process data. It was further found that a sampling interval time of longer than 4 minutes produced data with no significant correlation to reality. The dynamics of the flotation process has been misjudged in the past but can be quantified with the availability of real-time grade measurement based on diffuse reflective spectroscopy. The objective of the study was to compare the dynamics of different sulphide flotation processes through the comparison of maximum sampling interval times required to combat aliasing. All data were collected from single stream analyzers that are currently installed at mineral concentrators. The technology used is based on diffuse reflective spectroscopy."

Jan 1, 2012

By Stuart Elliot

Brownfield project portfolios are notoriously hard to manage. Day to day there is a constant stream of changes and challenges within projects and across the whole program. When the budget year is over, we?re often left wondering: did the facilities get what they really needed? Did we get value for the capital that was spent? Did we get all the project control and process improvement that we paid for? Great work has been done over the years by the Project Management Institute, Construction Industry Institute and Independent Project Analysis to identify what leads to project success, develop project delivery systems and equip project leaders to perform better. But is attention to individual projects all we need when the job is to deliver a portfolio of many projects? Let?s work with an analogy for a moment, and say a project is like a car, and a project manager the driver. Why can?t all the projects in the portfolio get home in time for dinner? The answer, of course, is that the commute home is about traffic, not just about cars. The road, the signals and the actions of other drivers affect us in our individual cars. Optimizing traffic flow is not about managing individual cars, it is about creating the conditions that allow all traffic to move as smoothly as possible. When we?re stuck in traffic, it doesn?t really matter that we are skilled drivers who know our exact location and our engine?s vital signs. Success with a brownfield portfolio requires more than the equivalent of driver training and a good GPS in every vehicle. Managing the annual budget requires more than tight management of each project. This is not a suggestion to abandon project management in the brownfield multi-projects world; the idea is to find and apply the right tools for delivering a portfolio. Remember, we want confidence in 3 areas: 1. that the facility is getting what it really needs, when it needs it 2. that we are getting value for money invested in facility modifications and improvements, and 3. that our controls are adding value by guiding our improvement What are those portfolio tools? The job they have to do is distinct from project-level thinking: ? Create a clear and balanced business pull for project ideas ? Maintain a respectable plan for fiscal, resource and business control ? Organize the work into a steady flow ? Manage the nature and timing of value-driven project substitutions and priority changes ? Focus on overall business value added and best use of resources ? Repurpose the projects organization into being the way the facility gets improved

Nov 1, 2011

By Faruk Oksuz, Phillip L. Covell, Martin Doll

A series of difficult ground conditions causing high groundwater inflows and hazardous gas intrusion abruptly halted the construction of a 6.4-meter (21-foot) finished diameter and 1,890 meters (6,200 feet) long tunnel planned to serve as a 4-millioncubic meters (1-billion gallon) per day capacity river outfall for treated wastewater. Some 808-meters (2,650-feet) section of the constructed tunnel, TBM, and all other tunneling equipment were completely flooded with hydrogen sulfide laden artesian groundwater. The subsequent pumping and tunnel recovery efforts were unsuccessful and the tunnel was abandoned. In the end, the construction contract was terminated and options to redesign and reconstruct the project were re-evaluated to maximize the use of already constructed tunnel facilities such as the construction access and inter-mediate shafts and six outfall diffuser shafts in the river.

Jan 1, 2007

By Mathew Avery, Colby Barrett

In November 2016, a 7.8-magnitude earthquake caused more than 100,000 cubic meters of rock and debris to tumble down and bury the transportation infrastructure below Ohau Point in New Zealand. All routes between the northern and southern portions of South Island were severed. To undertake the rebuilding efforts, the New Zealand government established North Canterbury Transport Infrastructure Recovery (NCTIR) – an alliance to repair the road and rail networks between Picton and Christchurch. NCTIR’s aim was to have the road open by Christmas 2017, but work also continued into 2018 to complete a number of safety improvements along the highway. The presentation will review the initial remediation attempts, the necessity to re-evaluate the original efforts, the need to incorporate techniques that were “outside-the-box” and different from traditional methods, and the logistics and planning that were required to complete the work safely. INTRODUCTION Shortly after midnight on Monday 14th November, a magnitude 7.8 earthquake struck the small South Island settlement of Waiau in North Canterbury, 100km north of Christchurch. The quake was the largest in New Zealand since the magnitude 7.8 Dusky Sound earthquake in 2009 (GNS 2016). While shaking was widespread with over 15,000 recorded ‘felt reports,’ the worst shaking occurred about 50 seconds after the quake rupturing started. The energy of the tremor progressed north over several minutes with surface rupture recorded on a total of 21 faults. The length of all the fault ruptures combined was close to 100km (GNS 2016). The degree of ground shaking was high, recorded as Modified Mercalli Intensity Scale (MMI) Level 8 – Severe. This level of shaking causes considerable damage in ordinary buildings with partial collapse including fall of chimneys, factory stacks, columns, monuments, walls, etc. At a human level, people experience difficulty standing; while furniture and appliances shift. Geologically, the damage depends on the geological setting. In Kaikoura and the surrounding area, especially the coastal highway State Highway 1, north and south of the town, many of the slopes consist of over steepened weathered, fractured greywacke. During the quake, the shaking caused significant and widespread damage with a total of 26 major slips (and many smaller slips); closing both State Highway 1 and the Main North Rail Line between Picton and Christchurch.

Jan 1, 2018

By E. R. Maize

This report is t e second of s series on roof movement in coal mines. The first (R. I. 3355)4/ dealt with convergence of roof and floor and movement of the surface accompanying and following extraction in a mechanized mine in which retreat of rib lines was rapid. The studies reported herein were made in a mine in which all the coal is loaded by hand, and movement of the rib lines was much slower in consequence. In choosing a site for this work, it was decided that the mine selected should have natural conditions akin to those of the first study and entirely different methods of working. To this end a cooperative agreement was made with the Crucible Fuel Co. through W. J. Whitaker, secretary, for conducting the work in the company?s Crucible mine, operating in the Pittsburgh bed in Greene County, Pa, This paper gives an account of the methods used in the investigation, excerpts from the data obtained, and such generalizations as can be made.

Jan 1, 1939

By Fred D. Fox

Introduction Abandoned mill tailings deposits can be found throughout the northern Black Hills of South Dakota, indicative of mining activities that originated during the great gold rush days of 1875. The Refuse Act of 1899 attempted to regulate the deposit of debris from mines and stamp works. But, in most cases, huge volumes of mine and milling wastes were disposed of in ways no longer considered environmentally acceptable. Restoration of gold mill tailings deposits is a relatively new practice to the Black Hills area. This discussion will present an overview of the environmental setting, environmental problems associated with past tailings disposal practices, practices being implemented to solve these problems, and prospects related to present the future tailings disposal practices. Environmental Setting An understanding of climatic characteristics, geology, surface and ground water hydrology conditions, and the physical and chemical characteristics of selected mill tailings deposits will aid in understanding environmental problems associated with tailings disposal and restoration. Climate The Black Hills region is in the middle latitudes, which have a

Jan 11, 1984

FOR rapidly marking in geological and topographical features on parish plans, the author has used the Veeder cyclometer with very satisfactory results. A simple Veeder cyclometer, usually retailed at cycle depots at 4s., is fixed to the axle of the front wheel of an ordinary bicycle. The cyclometer is desigued to read in miles and tenths of miles, which are recorded through gearing actuated by a striker on a spoke of the bicycle wheel engaging one of the vanes of the cyclometer once every revolution.By using 80 strikers the reading would be in chains and tenths of chains; therefore the use of 8 strikers gives the reading in chains, utilizing all the figures. The cyclometer is designed to be placed on the right-hand side of the bicycle, and takes up a minimum of space, being only about the size of the top joint of the thumb. With some makes of cycles there is insufficient clearance, so the cyclometer must then be placed on the left side, and the 8 strikers made to engage the top vanes, as shown in the sketch (Fig. 1).Very accurate readings can be obtained by this instrument. The author has found by numerous tests that the maximum error...

Jan 1, 1916

By W P. Player

The legislative operating environment, or the mineral regime, that a country has to offer is one of the key determinants that a company wanting to invest in an area takes into account in formulating its investment decision.   The New Zealand Government recognises this and the importance of getting the regime right in order to provide for continuing investment in mineral exploration and mining in New Zealand . In recent years, the Government has given considerable attention to developing legislation which provides for investment to take place; for those making the investments to have a stable, fair and open investment environment with government intervention only when considered absolutely necessary because other approaches are not working; and for the people of New Zealand to know that investment must meet acceptable health and safety standards and have acceptable impact on the environment. Also of key importance is having a clearly defined mining regime which includes rules on how to obtain a permit and rules in respect of ongoing permit compliance, rights to develop a mineral resource and permit conditions (in particular, the royalty regime). In New Zealand , these matters will all be addressed in what are referred to as 'minerals programmes'.   The Crown Minerals Act 1991, which is the legislation governing the allocation and management of permits for Crown owned minerals, requires that the Minister of Energy prepare minerals programmes. Minerals programmes establish the policies, procedures and provisions that the Minister shall follow in exercising his or her functions and powers under the Crown Minerals Act. Minerals programmes set out the principal reasons for and against adopting these policies, procedures and provisions and also restrictions on prospecting, exploration and mining for Crown owned minerals. Essentially minerals programmes define the mining regime for the minerals to which they apply, other than the taxation regime, environmental and health, safety provisions, land access matters and general matters concerning the investment climate.

Jan 1, 1995

By M. J. Farrell

The threat of global warming and its prominent position in public discussion and political debate requires all industry to take stock of its contribution to rising atmospheric concentration of greenhouse gases. For the primary metals industry, the first step must be to identify the pattern and range of emissions at each step in the production chain. Only then can the industry assess the economic consequences of the penalties on emissions that will be imposed by governments and regulators and devise cost-effective plans to avoid or mitigate such penalties. While some work has been done to estimate carbon dioxide (CO2) emissions using Life Cycle Inventory analysis, this approach is less useful than site-by-site emissions estimates. It is the level of specific emissions at each site that will ultimately deter-mine carbon taxation liabilities and participation in emissions trading schemes. Most mining companies have moved with the times to issue sustainability reports for their operations. But in the absence of any standardized reporting format, it is difficult to make useful comparisons between even the best-reported producers on a like-with-like basis. For this reason, Minecost.com modeled the use of fuels and energy used in mining, milling, shipping and metallurgical treatment to cover ?cradle-to-gate? emissions of greenhouse gases resulting from the production of the major base metals copper, zinc, lead and nickel. Greenhouse gas emissions ? overwhelmingly carbon dioxide ? are associated with the consumption of energy at every step in the production chain, from exploration through mining to the production of refined metal. Producers of primary metal employ diverse technologies to mine, mill, smelt and refine several different types of ore. Every orebody has its own special characteristics. In addition, most base metals are produced in concentrate that must be transported to smelters, with con-sequent emissions consequences.

Jan 1, 2009

By Yoshihiro Kawarabata

INTRODUCTION With only about 30% of Japan's entire population served by sewer systems at the end of 1980, extensive sewerage construction programs have been implemented. As major sewer networks in large cities are near completion, construction of smaller sewer networks in less populated areas and branch sewers in urban areas is on the rise, where a demand for sewer tunnels of 600mm to 1500mm diameter is very heavy. The pipe jacking technique, usually employed to excavate such small diameter tunnels, therefore has become the subject of further technological development and sophistication to cope with the increasing volume of construction. At the 1979 RETC, the state of the art on the slurry shield tunneling method at that time was reported. This paper is a follow up to the last paper and discusses a newly developed boulder crushing equipment and automatic pipe jacking system for the slurry shield method and their application. Such technological advancement as high-degree mechanization and automation will significantly improve tunneling operations in response to the aging society to come. Through application of the technique on so called factory automation, this is a step towards field automation for the construction industry.

Jan 1, 1983