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By Shamim A. Dar, Mohd Shuaib, K. F. Khan, Samsuddin Khan

The Late Paleocene–Middle Eocene phosphate nodules of Solan District of Himachal Pradesh belong to green facies of Subathu Formation of Sirmur group. Field observations indicate sporadic distribution of phosphatic nodules in the yellow brown to rusty brown, buff-colored bleach shales. Phosphatic nodules are dull earthy to dark grayish in color and break with sharp and conchoidal surfaces. Studies of phosphatic nodules using petrological microscope, X-ray diffractometry, and scanning electron microscopy (SEM) attached with energy dispersive X-ray (EDX) reveal that cryptocrystalline apatite (fluorapatite) is the dominant phosphate mineral. Silt sized silica is the dominant gangue, whereas pyrite and muscovite are present as minor gangue. The phosphate minerals occur as oolites, pellets, and cryptocrystalline apatite in the groundmass. Silica veins form a network replacing the original phosphatic matrix. Brown to brownish black color may be attributed by the organic matter in the phosphatic nodules. Completely phosphatized radiolaria and partially pyritized planktonic foraminifera are observed. There is corroboration of organic matter in the form of microbial filaments in the groundmass of apatite. The findings in the present investigation indicate that the different forms of the minerals, their texture, and distribution in the phosphatic nodules might be due to environmental vicissitudes in oxidizing to reducing conditions followed by replacement processes. Presence of microbial filaments may be due to the active role of microorganisms during the formation of these phosphatic nodules.

By Maurice Bottiau

It is a quite challenging objective to aim at covering in one paper the most recent evolution in piling and deep foundations technologies. This report has to be understood within the limits of the session 2b. It will therefore concentrate on the technological evolution of deep foundation techniques, addressing design issues only when directly related to execution aspects. For the same reason, it will not address the related codes, as a separate session of this conference is specifically dedicated to this topic. Monitoring and deep excavations being covered in other sessions, they will only be addressed when clearly relevant. We will try to show, from a practical viewpoint what are the main changes and the most exciting or critical issues over the last years, as they appear from the topics addressed in the literature or in the papers published in this session of the conference. As the paper mostly intends to explain trends and critical topics, it cannot be exhaustive, neither can it give the full description of the case studies. The author invites the reader to read the full papers, for a more complete description. We have divided our report in three main topics: Piling, soil improvement and treatment and retaining walls. Anchors and tie-backs will not be treated, neither tunneling.

Jan 1, 2006

THE North Mount Lyell Mine is situated on the southern side of Mount Lyell at an altitude of 1750 ft. above sea-level. The average rainfall is 117 in., and there are generally several light falls of snow during the year. Despite the heavy rainfall, which is fairly evenly distributed over each of the twelve months, the climate is equable and not unduly rigorous, and, provided that the mine employee is suitably clad, it is only on exceptional days that he experiences any discomfort by becoming wet journeying to and from the mine.The majority of employes reside at Queenstown, and are conveyed by special trains to and from the top of the haulage, which is less than a mile from the mine. The mean surface temperature at the mine is 46° F., with a maximum variation from 26° F. to 85° F., the relative humidity generally being higher than in other districts. The rock temperature is 48° F. on the 200-ft. or Main Adit level, and 54° F, on the 1200-ft. level, giving a rise of 6° F. for 1000 ft. in depth.The ventilation of the mine is natural, the downcast being served by the Crown and Blocks shafts and the Crown mullock pass, and the upcast air is carried away from the workings by the Main shaft and the Nos. 1 and 2 mullock passes. The quantity of air circulating varies from 25,000 cub. ft. to 35,000 cub. ft. per minute, the greater quantity moving in the colder weather. The downcast air in traversing the wet shafts becomes saturated and enters the level at the rock temperature of 54° F. in winter and about 56° F. in summer, while temperature readings of the outcast air indicate that it varies very little.In the southern end of the mine the Blocks shaft downcast air upcasts through the different stopes, and their mullock passes, to the level above for each level to the 700-ft. level, where it passes to one of the main uptakes. The prown shaft downcast air supplies...

Jan 1, 1927

By Mark S. Sanders

This report presents recommended visibility requirements for continuous miner, shuttle car and scoop operations and details the methodology used to generate them. A task analytic approach was used to define information requirements and visual features which served as sources of information. Information requirements were prioritized and the location of visual features determined. From this analysis, visual attention locations, containing one or more important visual features, were identified. A total of 71 locations-were identified for continuous miners, 54 for shuttle-cars and 54 for scoops. A procedure was developed for assessing whether operators in existing machines could be expected to see the visual attention locations. The procedure makes use of a Human Eye Reference Measurement Instrument (HERMI) designed for this project and an outside-in photographic procedure for documenting compliance with the recommendations. A sample of continuous miners, shuttle cars, and scoops were used to test the procedure. Results are presented in the report.

Jan 1, 1981

By Stephen Chung, Graham Mustoe, Joe Haid

In an open cast coal mining operation, a 305 m (1000 ft) long by 49 m (160 ft) thick overburden cast blast can produce more than a million cubic yards of broken muck that needs to be removed before the coal recovery process can start. In the Powder River Basin of Wyoming, it is common to see 30 to 40 percent of the overburden cast to a spoil that does not require rehandling with heavy equipment. Therefore, the higher the percent cast, the better the cast blast is rated. However, depending on the shape of the muck profile, there is often 20 to 30 percent of the muck standing in front of the high-wall. This portion of muck would require a number of dozers to push down to the dragline pad level. From the mine operator point of view, it is believed that for a given muck profile, there should be an efficient dozer pushing method such that a dragline pad can be developed in the shortest time. As a tool for analyzing this dynamic problem, a 2-D discrete element model, i-PushTM, has been developed to simulate a dozer pushing operation. This mechanistic model takes into account the dozer blade geometry, the dozer operating procedure (e.g. cut-depth, blade fill distance, forward and reverse speeds at specific slope angles), material density and cohesion. To demonstrate how i-PushTM can be used to help determine the most productive push routine, this paper presents three dozer push methods to compare the effectiveness of pushing at 3:1, 4:1 and 5:1 push angles.

Jan 1, 2006

By Franklin M. Grynkewicz

As part of the Boston Harbor clean up project, the new 1,000 mgd Deer Island Sewerage treatment plant includes ten 240 feet high egg-shaped "residuals" tanks. Contract documents called for these structures to be supported on 2,600 sixteen inch concrete filled pipe piles. The project site is underlain by highly variable glacial and marine deposits. Subsurface conditions vary from one extreme where firm glacial deposits exist at subgrade to the other extreme where 70 feet of medium stiff clays overlying weathered bedrock must be dealt with. The most common profile consisted of 15-20 feet of sands, 20-40 feet of marine clays, and 20-60 feet of stratified glacial deposits (commonly called tills) overlying Argillitic bedrock. Post bid redesign work, initiated as a cooperative effort between the owner and the general contractor, demonstrated that an $8 million savings could be realized if high capacity 48 inch diameter caissons replaced the specified pipe piles. A highly unusual arrangement of having the general contractor and specialty subcontractor providing input to the owner's engineering team allowed the redesign work to proceed on a "fast-track" schedule.

Jan 1, 1992

By Donald Bruce, Mark Harris, Wesley Schmutzler, James Sanders

"This paper evaluates the history, construction and most importantly the performance of two remedial seepage cutoff walls installed in two major dams in the United States. Beaver Dam, on the White River in northwest Arkansas, was completed in 1966 and seepage through the karstic limestone under the embankment was apparent almost immediately upon filling of the reservoir. Several attempts to stop the seepage by grouting were unsuccessful. In 1994 a cutoff wall consisting of secant piles drilled with 32"" diameter down-the-hole hammers to a maximum depth of 185'?was completed and the seepage was reduced to a negligible amount. It has been over 20 years since the completion of the cutoff wall, and all indications are that the cutoff wall is performing as expected. Walter F. George Lock and Dam on the Chattahoochee River near Fort Gaines, Georgia, was completed in 1963 and suffered the same problem as Beaver Dam due to the limestone on which the dam was founded. Cutoff walls were installed in both embankments (1980s) and solved the problem in these areas, but under-seepage at the concrete lock, dam and spillway structures increased to the point that remediation was essential. The cutoff wall had to be installed through 110'?of water and another 100'?into rock upstream of an active dam that continued to generate electricity during the construction of the cutoff wall. A secant pile wall, in combination with a diaphragm wall, was completed in front of these structures in 2004. It has been over 10 years since the completion this cutoff wall and, again, the cutoff wall is performing as expected. The paper describes the construction of these cutoffs, but focuses on the long-term performance in terms of controlling seepage and piezometric levels.BEAVER DAMBeaver Dam is located on the White River, 609 miles above its mouth, in Carroll County, Northwest Arkansas. The construction of the dam and Beaver Reservoir was authorized on September 1954 by the Congressional Flood Control Act for purposes of water supply, flood control and hydroelectric power generation. The dam site was selected in 1957: construction began in November 1960 and was completed in June 1966. (FIG. 1)"

Jan 1, 2017

By J. D. Steenkamp

In a paper presented at the Heavy Minerals Conference 2001 a laboratory scale investigation on the beneficiation of an ilmenite containing waste stream by magnetizing roasting was reported1.This waste stream contained a high concentration of ilmenite, which was contaminated by chromite and other gangue minerals. Interpretation of the results of the investigation was based on the assumption that during magnetizing roasting of an ilmenite concentrate, under the oxidizing conditions, the magnetic properties of the chromite would remain constant. In this article the following hypothesis was tested: The magnetic susceptibility of chromite would remain constant during magnetizing roasting of an ilmenite concentrate under the oxidizing conditions reported by Gouws and Van Dyk1. The results of this study indicated that the hypothesis is not true. The increase in the magnetic susceptibility is not significant though and it is expected that it will not influence the final ilmenite quality to a large extent. Based on the assumptions that the bulk magnetic susceptibility of the waste stream samples represents that of the ilmenite in the waste stream, and the bulk magnetic susceptibility of UG1 chromite that of the chromite in the waste stream, the results also served to confirm that the waste stream with a high chromite content should be roasted under oxidizing conditions, in a reactor with a well-defined retention time distribution (i.e. a fluidized bed reactor), at a roasting temperature of 750°C (rather than the higher temperature ranges of 800°C and 850°C).

Jan 1, 2003

By B. P. Watson

Several large falls of ground occur annually in the narrow, tabular stopes mined in the Bushveld Complex. These falls comprise safety risks and cause substantial production losses and compromise efforts to increase productivity. Underground observations in conjunction with instrumentation sites were used to establish the strategic parameters required to describe the rock mass behaviour of shallow-dipping stopes on the Bushveld platinum mines. Existing rock mass rating systems were evaluated using the observations and instrumentation results. None of the current systems adequately described all the relevant geotechnical conditions. Thus a hybrid of several current systems was developed, and the proposed system is discussed in the paper. The new rock mass rating system is termed the ?New Modified Stability Graph? system and follows the method originally described by Mathews et al.1and revised by Hutchinson and Diederichs2.Changes have been made to some of the tables provided by Barton3and to the stress analysis suggested by Hutchinson and Diederichs2. In addition, the logistical regression analysis has been applied to databases, formed using the suggested analyses, for three support resistances and risk levels established.

Jan 1, 2004

By D Porta, E Grigolato, K Behrens

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Aug 12, 2013

In constructing a financial model of a project significant effort is expended on capital and operating cost estimation, commodity price forecasts, and choice of discount rates while uncertainty in the primary input, the reserve, is often completely overlooked. The aim of this paper is to highlight the impact of uncertainty in the resource/reserve estimation process on the assessment of the financial performance of a project. Four qualitative processes have an impact on resource/reserve uncertainty. These stages are: 1.Ore definition 2.Geological interpretation 3.Resource estimation 4.Ore reserve estimation and mine planning. Each stage contains a number of tasks that may be considered as key performance activities (KPAs). Optimizing the manner in which these KPAs are completed can remove a great deal of uncertainty and error from the resource/reserve process. Examination of these KPAs within a company can also provide an insight to the quality of the information underlying the project. This will allow the company to identify any shortcomings in the data and to assess the resulting risks (Gilfillan, 1998). A hypothetical financial model based on a gold operation has been used to estimate the potential effect of resource/reserve uncertainty on revenue. Monte Carlo simulation has been employed to simulate a number of hypothetical scenarios: 1.a base case scenario which assumes no major errors or biases, but contains realistic margins for uncertainty that would exist in any project where work is being completed to the limit of best endeavours 2.a poor sampling scenario which assumes poor sampling practice and lack of understanding of sample preparation 3.a poor resource estimation scenario which assumes poor modelling and inappropriate choice of interpolation technique, and 4. a ?typical? scenario which represents a project where the majority of KPAs are not performed as best as they could be. The results show that realistic uncertainty ranges can generate changes in the estimate of potential revenue of plus or minus 30%.Therefore, it is important to allow for errors in these processes in any financial analysis or feasibility study. It is recommended that, when building a financial model, are view of relevant resource/reserve KPAs be carried out and appropriate ranges for uncertainty be applied to provide a range of potential outcomes. These outcomes can then be factored into the detailed cash flow analysis in order to ensure that technical uncertainty is built into financial decisions.

Jan 1, 1999

By Douglas Bartley, Robert McClure

This paper discusses the advances in programmable, testable high accuracy electronic detonator technology. The operation and safety of electronic detonator systems are required to meet rigid safety standards and withstand the demanding environment of in-field applications. These requirements are discussed through comments on existing safety requirements in Europe.

Jan 1, 2000

By C A. Feebrey, R A. Duncan

The Ebor Volcano in north eastern New South Wales is an eroded example of a central-type intraplate volcanic-intrusive complex. It is of Miocene age (19 - 20 Ma) and has similarities to other central-type volcanoes in eastern Australia which may represent manifestations of sub-lithospheric hotspot activity. Thick lava flows are exposed around the Great Escarpment and are dominated by a tholeiitic basaltic suite, ranging from ol-tholeiite to qz-tholeiite to icelandite with ages of 19.2 - 19.6 Ma. On its western edge, the tholeiitic lava suite probably overlies remnants of basanite flows belonging to the Eocene (~48 Ma) Doughboy province, but elsewhere, minor alkaline basaltic lavas may be coeval with the tholeiitic suite. Several felsic bodies were emplaced into the volcano at ~19.0 - 19.2 Ma and include subalkaline and peralkaline types. The Crescent Complex is a Miocene-age, strongly differentiated mafic to felsic intrusion in basement rocks and centrally located in pre-erosion reconstructions of the Ebor Volcano. It is interpreted to be a major feeder for the tholeiitic lavas based on age and composition. Evolution of the dominant tholeiitic suite proceeded from a parental ol-tholeiite magma, through qz-tholeiite, icelandite and small volumes of felsic rocks by fractionation of plagioclase, olivine, clinopyroxene and titanomagnetite, accompanied by enrichmentof SiO2, SFeOlMgO, alkalies and HFSE.

Jan 1, 1995

By Peng Jiahong

With ultrasonics application during checking the large diameter cast-in-situ pile body, it is usualy applied the statistical method of probability and PSD. This paper presents a converse probabilistic-analytical method which can identify important anomalies, both strong and weak, during interfered situation. So the inhomogeneity in concrete pile may be ellectively distinguished. In order to ensure the capacity of bed rock support layer under large diameter pile, a test-in-situ is conducted to determine the compresive strength and shear force inserting rock of the support layer, so the compresive strength and modulus value of elasticity of bed rock tested will closely tally with the actual situation.

Jan 1, 1991

By M. van Schoor

Coal remains South Africa?s most abundant and cheapest source of energy, and there is an ever-increasing necessity for optimal and safe extraction of the remaining reserves. Increasing focus on cost-effective mining and zero harm to the environment and miners has resulted in a shift in attitude towards the application of geophysics in local coal mining and exploration. Furthermore, technological advances have contributed to geophysics being embraced more readily by the coal mining industry, compared to a decade or two ago. Predictably, the growing interest in geophysical technologies has also created a need for education and training in the basic principles and application of geophysical methods, as local coal mining companies generally do not have in-house geophysicists. Consequently, the Coaltech Research Organisation?s Geology and Geophysics working group forum compiled a textbook aimed at addressing this need: to produce a guide for applying geophysics to coal mining problems in South Africa. The target audience for such a book would be coal geologists, mine surveyors, mine planners, and other mining staff with limited or no geophysics background. This paper provides a very brief overview of the book by summarizing key sections and selected examples. In doing so, the value of geophysics to solving a range of coal mining and exploration problems is highlighted.

Jan 1, 2014

By Narendra N. Khatri, Michael Deutscher, Jozef F. Zurawski

Five sewer connections were required to divert Combined Sewer Overflow (CSO)from existing outfalls to an old underutilized large diameter brick sewer (the Easterly Interceptor). The connections were part of an on-going CSO control program by the Northeast Ohio Regional Sewer District (NEORSD) in the City of Cleveland, Ohio. Each connection was made by pipejacking and hand-mining a fiberglass-reinforced polymer (FRP) pipe through soft glaciolacustrine clays and silts. Jet grouting was utilized to stabilize the soils and fill the voids surrounding the interceptor prior to making the underground connection. Reinforced concrete liners were constructed inside the aging brick sewer to provide structural stability during ground improvements and connection work. The project also involved micro tunneling two approximately400 foot lengths of FRP pipe through soft ground using a slurry pressure balanced machine.

Jan 1, 2005

By Robert Bittner

The following is a report on the development of two unique and separate cofferdam systems used in the construction of the marine foundations for the I-205 Columbia River Bridge at Portland, Oregon for the Oregon Department of Transportation. The first of these two systems utilized interlocking H-pile 100 ft long to form a cofferdam 145 ft by 58 ft in plan and 100 ft deep. The second system consisted of two immense bell shaped steel forms. The larger of the two forms was 83 ft by 66 ft in plan, 62 ft high and weighed 450 tons. This form was externally stiffened for a designed hydrostatic head of 54 ft. Both forms were designed, except for the top 14 ft, to be set and stripped in one solidly welded unit. The supporting geological formation for the bridge foundations is the Troutdale, a cemented sand and gravel. This formation is at the ground surface on the Washington Shore and slopes downward to a depth of 115 ft below normal high water at about mid-channel. In this area the Troutdale formation is covered with a layer of fine to medium sand 90 to 100 ft thick. It was the variable depth of the Troutdale which determined the two types of foundations and the corresponding to the two cofferdam systems.

Jan 1, 2013

By L. F. Stutzman, George Thodos

A new graphical method, which is a modification of that proposed by Buckley and Leverett', is presented for the determination of the displacing fluid saturation at breakthrough for frontal drive mechanisms. This method is applicable to all types of fluids, which may be either soluble or insoluble in the oil at reservoir and injection conditions. This adaptation has unique advantages in handling problems in which either liquids or gases are the displacing fluids. INTRODUCTION In the displacement of oil from a reservoir with water or gas injected into the formation or by the expansion of a gas cap, the determination of breakthrough or flood advance is important to define the initial and subordinate phases of the operation. Thus, the determination of the displacing fluid saturation at breakthrough is fundamental to the establishment of over-all reservoir production. Methods for analyzing this saturation and for calculating production rates have been previously reported1,'*".". All of these methods utilize the rate equation for linear flow developed by Buckley and Leverett1. xs = QT - Qn/A? (?fu/?Su) .....(1) Sp where f, represents the volumetric fraction of displacing fluid in the total flowing fluid within the reservoir as is defined by: fo = 1/1+ ku/kd µn/µn .......(2) Since the time, ?, necessary for the flood front to travel distance ?X is unknown, Eq. 1 cannot be solved directly for the determination of the breakthrough point. Therefore, it becomes necessary to solve Eq. 1 simultaneously with an equation representing a fluid bal-ance on the reservoir behind the flood front. To develop such a fluid balance equation, it has been assumed that the fluid composition is uniform in the reservoir behind the flood front. Based upon this assumption, the follow-ing equation can be derived from a material balance on the displacing fluid: x = (?X) s Dx ? x=0 [ Snx - Sn1 ] dx = QT - Qn/A? It is readily observed that the displacing fluid satura-tion behind the flood front, Snx, may be determined through the simultaneous application of Eqs. 1 and 3. Although the approach may vary, this objective re-mains the same for all of the previously mentioned graphical or analytical methods. After Sox is determined, it is then possible to calculate the gas-oil and/or water-oil ratios and the rates during the initial and subordinate phases of production, and thereby define the production history of the reservoir. In this presentation only the de-termination of Snx is considered, and the reader is re-ferred to the several texts in reservoir engineering2,4,5 for a complete discussion on the methods for establish-ing the production history of a reservoir. PROPOSED METHOD FOR DETERMINING Snx Since at any time the quantity, QT - Qn/A? is a constant, Eq. 1 may be expressed in differential form as follows: dxsn = QT - Qn/A? d (? fn/? Sn) sn .....(4) Eq. 4 may be substituted directly into Eq. 3 to obtain: ? fn/? Sn ? [ Snz - Sn] QT - Qn/A? d ( ? fn/? Sn) = QT - Qn/A? ...............(5) Eq. 5 simplifies to the expression: ? fn/? Sn ? [ Snz - Sn] QT - Qn/A? d ( ? fn/? Sn) = 1 ....(6)

Jan 1, 1958

By Stephen M. Smading

The Jinping-II hydroelectric project in China features four parallel headrace tunnels approximately 18-km- (11-mile-) long. Two will be excavated by tunnel boring machines (TBM) and two by drill-and-blast. A nearby fifth tunnel is being excavated by a 7.2-m (23.6-ft) TBM to draw down ground water in advance of excavating the headrace tunnels. Unique onsite assembly of a 12.43-m (40.7-ft) main beam TBM and backup system was completed on Sept. 18, 2008 in the remote mountains of the Sichuan province. The equipment was assembled onsite, without previously having been assembled and tested in a factory, using a method called onsite first time assembly (OFTA). This paper addresses the following topics: ? Project description including geology and terrain. ? The decision process leading to onsite, first time assembly, the assembly process and logistics, and lessons learned. ? Design features of the TBM and backup system. ? Operational history from startup to the writing of this article.

Jan 1, 2009

Recent advances in GPS, machine guidance technology and telemetry allow an unprecedented level of control of surface mining operations. GPS technology can now locate the bucket of a shovel or the blade of a dozer within 50mm (2 inches).Some of the outcomes possible are: precise selective mining – even when the ore is visually indistinguishable from waste: tracking grade and tonnage of every ore parcel through the mine: real time productivity monitoring: detailed post accident safety analysis: tracking the movements of every piece of equipment. This paper will consider the contribution that GPS based machine control systems can make to ensuring that surface mining projects deliver the outcomes promised in the feasibility studies. Case studies of installations are presented.

Jan 1, 2004