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By Jean-François Lapointe

Many advances have been made concerning the automation of heavy equipment teleoperators such as those found in mining. Complete automation, however, is not achieved yet and the operation of these vehicles still relies on the presence of a human operator. Fortunately, a lot of research has been done in order to improve the performance of these human-machine systems. This paper presents the characteristics of different control modes and input devices used for the control interface of those telemanipulators. We describe the benefits and drawbacks of each particular control interface on the overall system performance, based on a review of research in the field. We conclude with some recommendations and a discussion of future research needs, given the new potential advances offered by virtual environment technology and embedded computing.

May 1, 2001

By Brian W. Mackenzie

"This paper briefly outlines the characteristics which should be considered in assessing the economics of mineral exploration, and illustrates such an assessment by using data from the Canadian base metal sector. Implications for the sector are found to include the following:(1) base metal exploration has the potential to create a substantial amount of new wealth;(2) investment incentive for exploration under current conditions is not unattractive over-all;(3) because of existing taxation policies, there is much more incentive for large companies to explore than for smaller enterprises;(4) succesful exploration is sensitive to the size, financial resources and organizational structure of the exploration entity;(5) the general level of recent exploration expenditures should be adequate to maintain the current rate of production and perhaps to support very modest growth; and(6) there is an important opportunity for growth in the sector.The findings of the study suggest that government policies should be made more flexible, in order to take into account the risks associated with exploration and with price fluctuations in the base metal sector. Recommendations are also made concerning improvements in provincial regulations for disclosure of exploration information."

Jan 1, 1981

By B. McLaughlin

Agnico-Eagle started sinking the Penna Shaft in 1995 with a hoisting plant capable of hoisting 1800 t/d from a 2240 m deep shaft. Exploration success led to the installation of a hoisting plant capable of extracting 4500 t of ore and 1800 t of waste per day from a depth of 2210 m. The introduction of a new rope selection factor, permitting a safety factor of 4.0, represented the breakthrough required for a cost-effective project. This paper describes the process taken to introduce the new rope selection factor and its impact on the original plant.

Jan 1, 2004

By W. D. Gould, A. Kapoor, K. Morin, P. Bédard

This paper presents the results of a research study that is being conducted by the Mine Effluents Program, Mining and Mineral Science Laboratory (MMSL), Natural Resources Canada aimed at evaluating biotechnology processes for the treatment of nitrogen compounds such as thiocyanide (CNS) and ammonia (NH4-N) which are present in gold mill effluents. A sequencing batch reactor (SBR) technology, commonly used for the biological treatment of municipal and industrial effluents, was used in this study. In the SBR process, the micro-organisms were able to degrade CNS to NH4-N and NH4-N to nitrate (NO3-N) at operating conditions of two 12 h treatment cycles per day, with pH maintained in the 7.4 to 7.6 range, and at room temperature (approximately 21°C) and also at 12 °C. The end products of CNS and NH4-N biological oxidation were NO3-N and sulphate (SO4) that are relatively non-toxic. Partial removal of NO3-N was achieved by biological denitrification reactions in the SBR process. The SBR process effluent was measured to be non-toxic to rainbow trout based on the 96 h acute toxicity test. The microbial consortium isolated from the SBR treating a simulated effluent was able to effectively oxidize CNS and NH4-N to NO3-N in water samples (under batch conditions) collected at three mine sites located in Quebec, the Northwest Territories, and Yukon.

Jan 1, 2004

By E. Poiate, P. R. Cabral, A. V. N. Santos, P. V. M. Costa, C. S. Amaral, A. M. Costa

This paper discusses the design of underground salt caverns, opened by solution mining, for the production of brine and storage of natural gas under high pressures. The caverns are located in the salt basin in Maceio City, Alagoas State, at the northeast region of Brazil. Special attention is given to the geomechanical structural design of the caverns using computer codes specially developed for the simulation of excavations in salt rock formations, considering validated constitutive creep laws under different initial stress states and temperatures. The behavior of sedimentary rocks intercalations presented in the salt layer is simulated using elastic-plastic models. The excavation of the caverns by solution mining is also simulated starting from a geostatic initial equilibrium state of stresses, with a unique formulation only implemented in these computer codes, without the need of the application of boundary stresses to the model in order to develop the initial state of stresses. These computer codes have being used in the design of several clusters of caverns for brine production used as raw material of Poly Vinyl Chloride (PVC) of the Chemical Industryin Brazil. These computer codes and methodology were also applied to the design of the underground conventional potash mine in the state of Sergipe, overlying tachyhydrite and carnallite with very high creep strain rate. They have also been used in the design of the pre-salt oil wells through thick layers of stratified salt rock in Santos Basin, for the exploration and production of the pre-salt reservoirs in Brazil. The constitutive creep equations implemented in the codes are based on a double mechanism creep law. The creep constants adopted in the simulation are taken from a previous investigation carried out on an experimental panel of the potash mine, considering the stratified geology with different salt rocks of the basin where the mine is located. These constants were also obtained by lab tests under different confined and differential stresses and temperatures.

Jan 1, 2015

By G. C. McKerrow

"Mr. G.C. McKerrow, Assistant Manager of Noranda Mines and formerly Smelter Superintendent attended the meeting to answer questions as to why smelters imposed penalties for too much zinc in a copper concentrate or too much copper in a zinc concentrate, etc.D.W. Bridges -Mattagami Lake MinesWhat limits do you set on zinc and lead in a copper concentrate?G.C. McKerrow - At Noranda, we allow 5% zinc free and charge 25 cents for every unit above that. For lead, it is 1% free and 25 cents per unit above that. Lead is a much more harmful impurity than zinc because it tends to recycle more in the smelter circuit and creates a greater health hazard in the plant.E. Thornton - Sullivan GroupWHat harm does fluorine do in the smelting process?G.C. McKerrow - Fluorine usually does not occur in harmful concentrations in non-ferrous smelters. Fluorides are present in exhaust gases in the aluminum and phosphate industries. If these fumes escape into the atmosphere, they may settle out on forage grasses in concentrations that are harmful to livestock.Thorton - Sullivan GroupI have asked this question other places and have been told that it is hard on brick linings and causes gold and silver to be lost up the stack.G.C. McKerrow - Almost any volatile constituent in a smelter charge will aid in carrying other metal values. To this extent it may be harmful.E. Thornton - Sullivan GroupMr. Tait mentioned before a smelter where they have a copper-tin ore and they pay for copper, tin, bismuth and silver but object strongly to indium in the concentrate. Why would this be?G.G. McKerrow - 1 can't see why indium would be a serious impurity. It does tend to concentrate in flu dusts and if you get enough of it you can recover it and sell it but I have never heard of anyone putting a penalty on it.Question - I once ran into a small copper mine in Peru that had cadmium in the copper concentrate but no zinc. The copper smelter charged a penalty for the cadmium. Why would this be?"

Jan 1, 1971

By A. J. Faulds, K. C. Westaway, Z. Waszczylo

"PAH compounds have been found in the exhaust from all types of engines burning hydrocarbon fuels . They have also been found in the air over cities and in water. The authors report on a study to assess the concentrations of twelve different PAH compounds in several different environments in dieselized underground mines. In addition, the differences in the PAH levels and distributions in different mines will be demonstrated. Finally, the influence of blasting and the type of diesel engine used as well as the effect of catalytic converters in the exhaust system on the PAH concentration in the mine will be discussed.IntroductionMining methods have been altered significantly in the last 25 years; i.e ., the tools and machinery used underground have changed from electrically operated trains and other equipment to diesel-powered equipment. This has been done for several reasons: 1) economics, 2) convenience and 3) safety. Today, most mines are heavily committed to using diesel equipment.Although the introduction of diesel equipment has revolutionized mining methods and has been a tremendous boon to the mining industry, it has also created new problems. These problems arise because the exhaust from diesel engines contains several pollutants which can be hazardous to the health of the miners. These pollutants are CO2, CO, NO., SO2, oxygenated hydrocarbons produced during the buring process and unburned hydrocarbons. There are two classes of hydrocarbons, of which polynuclear aromatic hydrocarbons (PAHs or PNAs) are a part."

Jan 1, 1981

By David D. Davidson

Commodities remain hot for the time being, but for how much longer? The bulls point to global economic growth lead by China?s insatiable demand for raw materials. To further emphasis the bullish view they point to the emergence of India for follow through demand. The bears remain convinced China?s growth is unsustainable and with higher interest rates and high oil prices, the United States economy is poised to slow. Both groups can make a convincing argument and both will be proven right in the fullness of time. Profitability and balance sheet strength for the mining industry has rarely been better. Is this a time to be bold or cautious? In this paper, the author will address the dilemma facing today?s management as they pursue growth and try to minimize risk.

Apr 1, 2005

By Margaret Anne Stephenson

Today, in Australia, it is increasingly common to see agreements between Indigenous peoples and resource companies being achieved generally as Indigenous Land Use Agreements or agreements pursuant to the ?right to negotiation? process under the Native Title Act 1993 (Cth). Despite progress in this area, resource development on Indigenous lands is not without its challenges for both the resource proponents and the Indigenous parties. History demonstrates that resource development on Indigenous lands has produced struggles between the traditional owners of the land and the resource proponents. In Australia their relationship is generally defined by issues of access to land and assuring continued access to the land for the life of the project. In this context, divisions in Indigenous communities often emerge. The proposed resource project can have the effect of polarising members of an Indigenous community. It may be regarded by some traditional land owners as an advantageous opportunity for the community and by others as a hazard to country and culture. The process of agreement making has proved not only a test for the Indigenous community but also for the resource proponent. In this paper we undertake a contemporary case study of a proposed Australian resource related-development project on Indigenous lands. This project involved a multi-billion gas hub precinct proposed at James Price Point in the Kimberley region in Western Australia. The James Price Point proposal produced a litany of challenges for all parties. The traditional owners faced fundamental social and human rights issues, including a minority opposition to the project, the project's potential cultural heritage impact, the threat of compulsory acquisition of their native title interest by a State government due to an initial failure to settle an agreement, a fracture of their unsettled land claim and a minority rejection of the agreement ultimately reached. Additionally, the ?green? lobby also rejected the proposed gas hub on environmental grounds bringing the green lobby into direct conflict with both the traditional owners in favour of the project and the resource proponent. Ultimately, Woodside announced its decision not to proceed with the proposed gas precinct at James Price Point, in April 2013. In this paper we analyse the complexity of the James Price Point gas hub negotiations with the traditional owners which resulted in an Agreement that promised to deliver substantial benefits for the Indigenous communities. We question why such a favourable and beneficial agreement for the Indigenous community also produced the plethora of challenges and concerns and we consider how future negotiation processes could be better structured to avoid the difficulties that have confronted Indigenous land owners and resource proponents alike.

Aug 1, 2013

By David Whalen

Mobile equipment in oil sand mining operations experience more maintenance problems than similar equipment in other surface mines, due to soft underfoot conditions. Oil sand properties are known to vary with temperature, bitumen content and previous loading cycles. One of the challenges is the widely variable underfoot pressure which supports shovels and trucks. In the case of a heavy hauler driving on in-pit roads, each tire is supported by a different ground stiffness resulting in an apparent uneven surface. Driving over uneven ground causes twist in the truck frame, which is transmitted to the dump body. Through a finite element analysis of a haul truck dump body, it was shown that slight frame twists produce localized stresses in the intersections of the floor stiffeners. These stresses are at times greater than those resulting from the maximum ore weight and are primarily responsible for cracking in these intersections. Syncrude maintains high quality haul roads, which are constructed of gravel, and makes every effort to keep the shovel pit roads as smooth as possible. This problem cannot be avoided through operational practices only and must also be accounted for in the design of haul truck bodies.

May 1, 2003

By A. Taylor, E. Thorn Corthay, R. Storey

In response to requests from its stakeholders, the International Standards Organisation is engaged in development of an international standard for Energy Management Systems (EnMS) which will become "ISO 50001". This new standard will build on the successes of both the EN16001 EnMS standard that has been used by dozens of European companies, as well as the ANSI/MSE 2000:2008 EnMS standard that is currently being used in several pilot projects in the USA and Ontario. This paper provides an overview of the key points of the EnMS standards, and describes how they can be used to drive sustainable energy reductions in the metallurgy industry.

Jan 1, 2010

By M. B. McClenaghan

"This paper summarizes diamond exploration techniques used in glaciated terrain, focussing on indicator mineral and geochemical methods applied to glacial sediments. Understanding the ice flow history, depositional history, and stratigraphy of glacial sediments is essential to successful sampling, interpretation and follow-up of indicator mineral and geochemical anomalies related to kimberlites. Kimberlite indicator minerals survive glacial transport over long distances and the relative abundance of each mineral in till is a function of the primary mineralogy of individual kimberlites. Indicator mineral distributions observed at a regional scale define the net effect of glacial dispersal, often along different ice flow directions. Local-scale distributions define individual dispersal trains. The medium sand (0.25 mm to 0.5 mm) fraction of heavy mineral concentrates, * GSC Contribution No. 2002028 prepared from glacial sediment samples, is best suited for indicator mineral surveys. The application of till geochemistry to diamond exploration is increasing because it is significantly cheaper than indicator mineral analysis and it can be performed quickly. The <0.063 mm (silt+clay) and 0.5 mm to 2.0 mm (coarse sand) fractions provide the best geochemical contrast between background and kimberlite-rich till. Kimberlite pathfinder elements that provide good contrast include Ni, Cr, Ba, Co, Sr, Rb, Nb, Mg, Ta, Ca, Fe, K, Ti and LREE, the relative importance of which will depend on kimberlite composition and that of the surrounding bedrock.IntroductionIn Canada, glacial erosion is the principal means by which kimberlite and its associated minerals have been dispersed, from a few tens of metres to tens of kilometres down-ice. Post-glacial weathering has had little impact on kimberlite debris in the glacial sediments, thus boulder tracing, indicator mineral methods and trace element geochemistry of the fine fraction of till (“drift prospecting” methods) can be used to detect kimberlite dispersal within areas covered by glacial sediment. This paper provides a summary of drift prospecting methods for kimberlite exploration in glaciated terrain, and includes examples of reconnaissance- , regional- and local-scale kimberlite indicator mineral and till geochemical distribution patterns.Weathered kimberlite is more susceptible to glacial erosion than the surrounding bedrock, thus many kimberlites in glaciated terrain are found in low or swampy ground, under small lakes, or covered by thin (< 1 m) to thick (>50 m) glacial sediments. Glacial erosion has removed varying amounts of the pre-glacially weathered kimberlite and, in some cases, the hard competent kimberlite below. For example, glacial erosion of the Peddie, McLean and Seed kimberlites near Lake Timiskaming, Ontario, removed pre-glacially weathered kimberlite, leaving a polished striated subcropping surface (McClenaghan et al., 1999a). In contrast, glacial erosion of the B30 kimberlite, near Kirkland Lake, Ontario (Fig.1), was much less vigorous and left a >10 m cap of soft and highly weathered dark green clay-rich kimberlite (McClenaghan et al., 1996). The thickness of remaining pre-glacially weathered kimberlite will influence the geophysical signature of the kimberlite."

Jan 1, 2002

By J. Aiello

"A brief history of previous mining activity on Coal Mountain, near Corbin, British Columbia, is followed by a description of the steps leading up to the resumption of mining in /974 by Byron Creek Collieries. New developments, including a preparation plant, a rail spur and a totally enclosed facility, as well as operating techniques, are also discussed. IntroductionThe Corbin Mine of Byron Creek Collieries Limited is located in southeastern British Columbia, approximately 110 air miles southwest of Calgary (Fig. I), 15 miles south of Highway 3 via a newly constructed provincial road (Fig. 2). Development of the area began on July 30, 1905, when D.C. Corbin, a prominent businessman from the northwestern U.S., and his associate E.J . Robert s, first visited the site of Coal Mountain on horseback. Coal was in great demand by railways and other industrial users, so the Corbin Coal and Coke Co. , after acquiring 15,000 acres of land in the area , began to develop a mine.F.J. Roberts was responsible for the construction of the 14-mile rail spur, the Eastern British Columbia Railway, which joined the mine to the CPR main line at the McGillivray Loop. Rail access to the mine and its developing community, Corbin, B.C., was completed in September 1908, the same year that the first underground mine began production.The Corbin Coal and Coke Co. operated six mines on Coal Mountain (Fig. 3), and production from 1908 to 1930 inclusive totalled 2,337,800 tons. This production was allocated to the mines as shown in Table 1. No.3, 4 and 6 mines were operated intermittently from 1931 to 1935."

Jan 1, 1980

By David W. H. Ellis

This presentation will discuss over 2 dozen past, present and future oils sands projects in Alberta. The very early projects as well as the most recent along with the ones that never got off the ground and the ones in production are all included. For each, the following will be given (where known): owners, location, type (mining/SAGD/refinery), production, capital budget, spent to date, status. Some overall impacts will be discussed.

May 1, 2004

By M. K. Gangal, M. A. Stoakes, A. E. Hall

"The major features of the CANMET thermodynamic mine ventilation network program, developed by the Mining and Mineral Process Engineering Department of the University of British Columbia for the Canada Centre for Mineral and Energy Technology (CANMET), are described.The program is designed for use by deep Canadian mines in planning ventilation flows where the effects of auto-compression of air, moisture lift work and natural ventilation are significant. Routines to simulate stalled fans and give an optional cost printout have been included in the program.A supplementary plotting program used to simplify data interpretation is also described.The program is described with a test data example of a deep mine. It is a valuable analytical tool which can assist ventilation engineers to simulate many alternative ventilation strategies at a low cost in a very short time.IntroductionCanadian underground mines are becoming deeper and more extensive. The use of more and larger diesel-powered equipment increases the amount of air required to be circulated in these complex systems. These effects, coupled with the increasing unit cost of the energy required for mine ventilation, require that the air is used with maximum efficiency.Optimum airflow distribution can be obtained by using network computer programs enabling engineers to plan future ventilation systems based on quantitative assessments. The programs used for deep mines must make allowance for the change of air density with depth, as the assumption of incompressible flow leads to serious errors. Natural ventilation effects may vary with depth and from part to part of the mine; this must be catered for by the program. The air moisture content changes throughout the circuit and a significant portion of the fan work may be used in removing moisture from the mine; as this work varies directly with the flow, a suitable relationship must be utilized in the program."

Jan 1, 1982

By Jamie Archibald

The Department of Mining Engineering at Queen?s University conducted a study of backfill practices in underground mines across Canada to assess the current state of backfill usage and to overview potential hazards associated with backfill practice, from preparation to transportation to placement. The primary aim of this study was to cover each component of a typical mine backfill system, and to identify potential incidents leading to the disruption of backfilling operations and any associated corrective actions. This paper, Part II of the study, deals with underground operations consisting of backfill transportation and backfill placement. Part I of the study, which deals with surface operations consisting of backfill material supply and backfill plant preparation, is also presented in these proceedings. A review of safety measures associated with current backfill operations and recommendations for procedures of best practice that should be implemented to reduce fill-related hazards in all mine backfill workplace environments are presented. In general it has been found that system failures normally lead only to minor losses to the operations.

May 1, 2009

By V. Budinsky

In recent years the global mining industry has addressed its social and environmental responsibilities and numerous factors have contributed to this. Corporate Social Responsibility (CSR) is an important part of mining company strategy for practical implementation of the goals of sustainability, transparency, accountablity and good relationships with stakeholders:- investors, employees and communities. A key stakeholder for all mining companies is the local community which is affected by the mining operations. Companies must identify the emerging social and environmental trends, study the interests and concerns of various communities, address their needs and maintain a positive relationship. The CSR programmes of Czech coal mining companies are focused on surrounding community initiatives and sustainable responsible business. Mining in the Czech Republic is subject to strict rules and regulations and supervised by the State Mining Authority. Mining projects undergo rigorous approval procedures which encompass all operational measures at the different planning levels ? such as public participation in the authorisation process for mining projects, the application of the Environmental Impact Assessment Directive, environmental sustainability programmes, innovative solutions and flexible options offered by the mining company. One very important part is the preparation of the mining-technology preconditions and developing the integrated planning process in which all socially and politically relevant subjects in the mining operation surroundings are included. In an in-depth debate, all stakeholders may jointly develop the concept, in accordance with democratic principles. The optimally conducted dialogue process needs broad communication bases, including setting up theme-related joint taskforces, together with good moderation and the highly qualified support of technical experts. Using a case study of Severoceske doly a.s. Chomutov (SD Company) and the Czech Coal Group ? Czech leaders in the extraction of brown coal, this paper aims to examine the community development approaches and the CSR effectiveness of large scale mining companies. This paper brings a review of CSR and other such voluntary initiatives in the mining industry&apos;s proactive steps to contribute to societal well-being in a meaningful way. Key studies are provided by the projects ? Region with Better Perspective?, ?Stop Dust for Healthy Brezno Village?, ?Clever Heads for the North? and ?Coal Safari?. CSR issues are managed throughout all stages of the mine operation and beyond, long after the mine closes (e.g. post-closure programmes of new landscape, alternatives for reclamation including generation of lakes in former surface mines, conceptualization of industrial heritage). Communities need to be given the opportunity to help themselves through participation in CSR projects rather than being recipients of financial gifts from the company. A fair balancing of interests is the basis of any successful cooperation.

Aug 1, 2013

By Olli Haavisto, Juha Timperi

"Accurate on-line assays of mineral slurries are the basis for effective operation of flotation circuits. Typically the elemental content measurements are obtained by an X-ray fluorescence (XRF) analyzer, which samples the process lines and performs the analysis concurrently line-by-line. For a more frequent measurement of each slurry line the XRF measurements can be complemented with reflectance spectrum information. In reflectance spectroscopy the absorbance properties of the slurry in the visible and near-infrared wavelength range are analyzed. The advantage of reflectance spectroscopy is that measurements can be obtained quickly and simultaneously from several slurry lines. However, since the shape of the spectrum is only indirectly affected by the slurry elemental contents, frequent calibration of the measurement against the XRF analyzer is necessary. This study elaborates the combination of reflectance spectrum analysis with XRF. Results of laboratory tests for different slurries are presented and the operation of the system in a copper-zinc flotation plant is demonstrated.IntroductionElemental analysis of mineral flotation slurries is the most important factor in evaluating the performance of concentration processes. Timely on-line assays are also used as the basis for controlling the circuits and ensuring that the grade and recovery targets are reached. X-ray fluorescence (XRF) is the dominant technology in on-line elemental slurry analysis, and typically centralized XRF analyzers are used. The advantage of a centralized analyzer is that one measurement probe can be used to acquire the data from several slurry lines. This reduces the overall operating cost of the system when compared to distributed analyzer system design with several measurement probes requiring maintenance and spare parts. Slurry samplers are installed in the interesting process flows and representative sample flows are brought to the analyzer, where the slurry is further sampled and measured consecutively by the XRF analyzer. Due to the centralized structure of the analyzers and consecutively measurement of the sampling lines the sampling interval per slurry line can be relatively long. In larger concentration plants with several sampling lines a typical assay interval is in the range of 10-20 minutes."

Jan 1, 2016

By The Staff

Introduction For many years the necessity of mechanization of all the underground services in the collieries of the Dominion Steel and Coal Corporation in the Sydney, Pictou, and Cumberland coalfields has been foremost in the minds of those concerned with the engineering and operating policies of the Corporation, and a gradual policy of the mechanization of these services has been undertaken over the years, until nearly all the underground services, except the actual loading of the coal at the face, have been mechanized. Early in 1928, experiments in mechanical loading were conducted which finally culminated in the installation of mechanical loading units in our No. 20 colliery in 1938. This attempt at mechanization of the final underground services proved unsuccessful because the workmen were not ready to accept complete mechanization, and the fruition of many years of study was delayed until the year 1947. During the ensuing years, the engineers and operators of the Corporation had studied the possibility of adapting to conditions prevailing in Nova Scotia mines the many types of loading equipment in use in the United States and Europe. The varied physical conditions which exist in the fields operated by the Corporation rendered it extremely difficult to apply the equipment and technique successfully employed in the United States, and more recently in Europe, and special techniques have had to be devised to meet the need of each individual colliery. Prevailing physical conditions in the Nova Scotia fields find no parallel for mechanization with those of any other part of the American continent.

Jan 1, 1949

By M. R. Hudec, M. A. Nikolinakou, P. B. Flemings

"We model the shale response to the large deformations associated with salt bodies, and we identify the implications of the stress changes for hydrocarbon exploration. We employ both the static and evolutionary approach, and show that while the static one can model actual geologic geometries, only the evolutionary approach can provide a detailed description of the stress history of shales, which is essential for predicting stress, porosity, and pore pressure and, more generally, for understanding Earth processes related to salt-hydrocarbon systems.INTRODUCTIONDuring the last two decades, understanding the stress, material behavior, and pore pressure in shales around salt bodies has become increasingly important. The energy industry routinely drills near salt (Beltrão, Sombra, Lage, Fagundes Netto, & Henriques, 2009; Meyer, Zarra, Rains, Meltz, & Hall, 2005; Seymour, Rae, Peden, & Ormston, 1993), because a significant number of hydrocarbon reservoirs around the world are found in layers dipping away from salt diapirs.Salt is a viscous material that cannot sustain deviatoric stresses. Under differential loading it flows, changes shape, and eventually relaxes to an isostatic stress state (Urai & Spiers, 2007). Therefore, emplacement of a salt body and its viscous relaxation process may cause significant deformation of the surrounding sediments, perturb their state of stress and create local overpressures (Dusseault, Maury, Sanfilippo, & Santarelli, 2004; Seymour et al., 1993). As a result, drilling near salt is particularly challenging, and problems leading to additional expense or even abandonment are common (Bradley, 1978; Dusseault et al., 2004; Meyer et al., 2005; Seymour et al., 1993; Willson et al., 2003).Historically, salt and the evolution of its cross section to the present day geometry have been studied using kinematic restorations (Rowan & Ratliff, 2012). This approach aims to explain the present geologic section through a sequence of plausible past sections; however, it does not model the constitutive response of the wall rocks, hence it cannot provide any prediction on their state of stress. Similarly, largestrain numerical studies (Albertz & Beaumont, 2010; Chemia, Schmeling, & Koyi, 2009; Goteti, Ings, & Beaumont, 2012; Gradmann, Beaumont, & Albertz, 2009) have focused on the rheological evolution of salt systems without modeling the geomechanical response of the sediments."

Jan 1, 2015