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By H. E. Williams

In view of the frequent occurrence of petroleum in other parts of the world, it seems odd that so large an area as is contained within the borders of Brazil should be without this product. This apparent deficiency may be due, however, to our ignorance of the regions in which it may exist. In some places, indications point to the probable existence of petroleum in ages gone by; and while the presence of petroleum pools may be problematic, in several regions conditions not unfavorable to their occurrence exist. Yet, Brazil has enormous oil resources in the rich oil-shales in different parts of the country. Many of these shales are very rich and only suitable processes for the extraction of the oil are lacking. At the present time, only a few small experimental plants are producing oil by distillation from these shales. These plants have been the subject of recent investigations by the Geological and Mineralogical Survey, a preliminary report of which is in the hands of the printer. The only regions where studies have not been made are the upper Amazon, the Acre, the Rio Negro, and the Peruvian frontier, which really seems to be the most promising field for explorations of any in the country. In the vast plateau region of the interior north of the 20th parallel of latitude, granites, gneiss, mica schists, and very old metamorphosed sedimentaries predominate. Later, sedimentaries occupy a minor position and, where found in the interior, represent a thin veneering resting on the older rocks. At several places near the coast they have a greater development and contain considerable beds of oil-shale and may, .in some cases, offer conditions favorable for the occurrence of oil. Such deposits are found in the Permian rocks of central and southern Maran-hao; in the Tertiary and Cretaceous beds along the coast of Alagsas Sergipe, Bahia, and perhaps farther south in Espirito Santo; and in the Parahyba embayment north of Cape Frio and in the interior Tertiary basin of eastern Sao Paulo.

Jan 1, 1921

By W. J. Rooney, James Fisher, W. O. Hotchkiss

During the summer of 1927, the Department of Terrestrial Magnetism of the Carnegie Institution of Washington joined with the Michigan College of Mining and Technology in conducting a series of earth-resistivity measurements in the Michigan copper country. The geological structure in this section is quite varied and fairly well known. The purpose of the investigation was to discover the correlation between the variations in electrical resistivity of large masses of soil and rock in place and the geological structure below the surface. The work done may be roughly divided into two parts: (1) Measurement and study of the variations in resistivity with depth, or with volume, to establish such general relations as exist between the two; and (2) the determination of the specific resistivity of various formations in order to make available more fundamental data which may aid in the interpretation of the results of the former type of measurement. A report by Mr. Rooney, which gives in detail the measurements made and the results obtained, forms the basis for this article. Measurement and Study of Variations in Resistivity The possibility of applying data from measurements of the physical properties of earth material to the study of the geological structure has long been recognized, and a number of methods for determining the position and character of concealed rock strata by means of seismic, gravitation, magnetic and electrical measurements made on the surface are being used with varying degrees of success. One physical property which varies widely for different materials, and hence affords an opportunity for distinguishing between them, is their electrical resistance. Locations • were selected where the geological structures were well known and where the depths to the water level and bed rock had been determined by drilling. The problem was to determine the value of measurements of resistivity and its variations as indications of the geological structure below the surface.

Jan 1, 1929

By L. C. Snider

NO important discoveries of petroleum during 1932 are reported from Canada. New Brunswick, which has a small production from one field, was inactive, and the production showed a decline from 6600 bbl. in 1931 to about 6300 bbl. for the year 1932. The old fields in Ontario increased from 123,000 to about 131,000 bbl. Alberta showed a decline of more than one-third, from 1,413,631 bbl. in 1931 to about 913,000 bbl. in 1932. This decline was due principally to the restrictions placed on the flow of gas wells in the Turner Valley field, from which the crude naphtha is obtained that accounted for more than 93 per cent of the production of Alberta and for more than 80 per cent of the production of all Canada in 1932. The starting of new wells to the limestone that produces the naphtha-bearing gas was prohibited late in 1931, and only wells started before that time were finished during 1932. One well was drilled in the Turner Valley field to a depth of 7555 ft., establishing a depth record for Canada. It passed out of the Madison limestone at 5560 ft., and encountered showings of oil in the underlying formations, probably of Devonian age. Commercial production had not been established by the end of the year. Commercial oil wells were brought in in two areas in Ontario which had previously been considered as productive of gas only— in the Dawn gas field, Lambton County, and in Raleigh Township, Kent County. The discovery wells had initial productions of about 50 bbl. per day, but no production of major importance is indicated. In Alberta, outside the Turner Valley district, two wildcats were drilled northwest. of Lethbridge in the Keho Lake vicinity. Both failed to make commercial producers in the Madison limestone, but one was testing upper sands at the close of the year. Good showings of oil are reported. A very small production was found in the Madison limestone in a wildcat well on the Twin River structure southeast of Lethbridge and another well has been started near by on what is considered on geophysical evidence to be a better location structurally. About 15 locations were made on the Canadian side of the border north of the Cut Bank development in Montana.

Jan 1, 1933

By S. E. Piper, E. M. Buchalter, R. P. King, E. T. Woodburn

The problems involved in an optimum decision making model for flotation circuit are, first of all, to characterize the feed material in terms of parameters which can quantitatively describe the network flotation action in terms of a feasible set of control actions. Once the characterization has been postulated, it is then necessary to devise tests relating to parameter sensitivity, in order that credibility of the model predictions can be assessed. Once a credible model is available, the optimum control set is determined by a hill climbing technique. Details will be reported as to the credibility of model predictions using the stochastic flotation model on a network and further, computational problems associated with hill climbing for a complex objective function are reviewed. Discussion is presented on use of the Rosenbrock technique with constraints and use of a modified objective function with constrained derivatives when employing Fletcher and Powell technique.

Jan 1, 1969

By P F. Knights

Mining companies are striving to achieve new levels of operational maturity and drive process improvement across the organisation in the face of unprecedented demand and limited supply of experienced human resources. Advanced analytics techniques can help overcome these fundamental challenges by applying data techniques not previously applied in mining. Today, decisions are usually locally optimised but do not achieve optimum capability for the value chain. Although more information is collected then ever before, it is difficult to link many sources of data together in the same place in real-time, for example plant history, maintenance, mine planning, logistics and engineering data. Consequently complex analysis of data is time consuming and requires specialist skills and knowledge, and is often neglected in the decision-making process. In the future, analytics will close the loop between analysing data and taking action. Analytics will become embedded in the business and routinely applied to improve decision making across the organisation, from senior management to operations and maintenance workers, but will not require specialist skills or be time consuming to analyse data. As analytics becomes embedded in the business process, decisions are supported by data (not on gut feel), and critically, data from many sources are integrated in real-time to improve the quality of decisions. Ultimately, predictive tools will help suggest, or even in some cases automate, courses of action. The main opportunities for analytics exist where the enterprise requires supporting technology to enable it to continue to evolve to higher level of maturity. This will be in the areas of asset management, rapid reconciliation and adaptive planning, and the inbound and outbound supply chains. Advanced analytics are also a key enabler for increasing the effectiveness and realising the true value of Remote Operations Centres to safely and efficiently support operations in remote locations with smaller workforces.

Jan 1, 2008

By G. Skybey

The Directional Drill Monitor (DDM) is an advanced instrument for real time in hole surveying. It was developed by Du Pont (Australia) to suit Australian gassy coal mining conditions. The instrument consists of three units: i. Down hole transmitter ii. Acoustic transducer iii. Data receiver processor unit (i.e. up hole unit). This paper describes the function of each unit in detail and highlights the importance of the DDM in long hole drilling efficiency. Surveying is carried out independent of hole depth. Each survey takes 2-3 minutes to complete, the frequency of surveying to control borehole trajectory is determined by the accuracy required for a particular hole. The DDM is currently being used successfully for long hole drilling in a number of collieries. A high degree of directional control has been achieved. Borehole trajectories were controlled to within +l¬2m of the planned path with intersurvey distances varying between 6 to 18 metres over distances up to 700 metres.

Jan 1, 1992

Companies involved in the mining industry are exposed to risks, referred to as corporate risks, as part of the business process. Directors and management should be aware of these risks and make appropriate business decisions to address each risk. If business risks are not addressed on a timely basis the consequences are likely to be serious and will adversely impact the ultimate success of the business.The key corporate risks are:Poor cash flow and treasury management. ò Incompetent or unmotivated staff.ò Poor product quality.ò Accounting systems that do not provide meaningful and timely information.ò Computer system deficiencies. ò Ineffective credit screening.ò Assets not adequately protected.ò New ventures undertaken that are either inappropriate or not adequately researched.Exposures to corporate risk should be dealt with by Directors and management by systematically identifying major risk areas and implementing appropriate internal and management controls to deal with such risk areas. Proper management controls and procedures include the setting of overall corporate objectives and policy, monitoring adherence to such policy, establishing early warning systems to highlight problem areas and maintaining security over assets.

Jan 1, 1990

By Z. D. Hora

Sev_eral dozen si lica occurrences have been reported from various parts of Brit ish Columbia. Some represent hydrothermal veins or parts of pegmatite bodies; other are recrystall ized sandstones. Several vein type deposits were mined for smelter flux and as a source of white chips for stucco dash and simi lar products. Some quartzites were studied as potential sources of high-grade silica for ferrosilicon and silicon metal production. The province's only production of silica for ferrosilicon has come from a pegmatitic quartz plug near Oliver in southern British Columbia. Its reserves are now practically depleted.

Jan 1, 1984

By W. J. Millard

Owing to a moratorium in the drilling of crown-land leases in Trinidad during the year of 1931, only 40 wells were spudded in during the first eight months as compared with 110 during the same period in 1930. Nevertheless the production will show an increase of about 400,000 bbl. over that of 1930. An estimate is given in Table 1. Since the oil produced in 1930 was 9,418,907 bbl. and that in 1931 probably will be 9,853,976 bbl., the year 1931 probably will see an increase of about 4.6 per cent. The gross production of crude oil in the colony has increased steadily year by year, with the exception of 1919, when there was a slight decline. A tabulated statement was given last year.' The Petroleum Times of March 21, 1931 (p. 413) gives the total production of 1930 as 9,418,000 bbl. and the average monthly production as 784,833 bbl. The same two items for 1931 are estimated at 9,853,976 and 821,165 bbl., respectively.

Jan 1, 1932

By Thiago Figueiredo Azevedo

Ligas de titânio e nióbio têm sido desenvolvidas devido a possibilidade de modificar as propriedades mecânicas por envelhecimento. No presente estudo ligas TiNb com diferentes concentrações de Nb e com adição de estanho foram obtidas por fusão a vácuo, deformadas a frio e posteriormente tratadas por diferentes tempos de envelhecimento. Foi observado que todas as ligas em todas as condições apresentam as mesmas fases ß, a” e ?, no entanto, apresentam diferentes microestruturas. Isso se refletiu nas propriedades mecânicas das ligas, onde obtevese maiores durezas com o envelhecimento em 48 horas em todas as ligas, esse aumento de dureza foi quase o dobro para as ligas com maiores teores de nióbio (Ti42Nb e Ti42Nb2Sn).

Aug 16, 2017

By Walter Kauenhowen

The crude-oil production of Germany without Austria during 1938 amounted to 3,864,518 bbl., representing an increase of 21.7 per cent over the 3,173,373 bbl. produced in 1937. Adding the Austrian production, the crude-oil production of the new German Reich totaled 4,259,717 bbl. during 1938, representing an increase of 25.3 per cent compared with the respective figures of the previous year. According to published official data, and using a conversion factor of 1 metric ton equaling 7 bbl., the oil production of Germany in 1938 was as shown in Table 1. A semiofficial publication1 states that the program of the crude-oil industry for the second year (1938) of the four-year plan was successfully accomplished. According to the same source, new drilling developments at the following localities were promising: Reitbrook near Hamburg, Heide in Holstein, Eicklingen-Sandlingen near Celle, Steimbke near Nienburg, Worms in the Rhine Valley, Gifhorn near Braunschweig, Mölme near Oberg, and at other places. The drilling activity for oil is illustrated by the figures in Table 2.

Jan 1, 1939

By Walter Kauenhowen

The crude-oil production of Germany without Austria during 1938 amounted to 3,864,518 bbl., representing an increase of 21.7 per cent over the 3,173,373 bbl. produced in 1937. Adding the Austrian production, the crude-oil production of the new German Reich totaled 4,259,717 bbl. during 1938, representing an increase of 25.3 per cent compared with the respective figures of the previous year. According to published official data, and using a conversion factor of 1 metric ton equaling 7 bbl., the oil production of Germany in 1938 was as shown in Table 1. A semiofficial publication1 states that the program of the crude-oil industry for the second year (1938) of the four-year plan was successfully accomplished. According to the same source, new drilling developments at the following localities were promising: Reitbrook near Hamburg, Heide in Holstein, Eicklingen-Sandlingen near Celle, Steimbke near Nienburg, Worms in the Rhine Valley, Gifhorn near Braunschweig, Mölme near Oberg, and at other places. The drilling activity for oil is illustrated by the figures in Table 2.

Jan 1, 1939

By M. F. Goudge

THE present century has witnessed an amazing transformation in the uses of limestone. From being mainly a structural material, a role it has played since the beginning of civilization, it has become one of the in-dispensable raw materials for use in the great chemical and metallurgical industries that play such a vital part in the economic life of the nations today. Its uses have become so diversified and numerous that it enters, directly or indirectly, into nearly every phase of modern life. In this introductory paper it is proposed merely to outline the general usefulness of limestone and to point out some of its salient features, and to leave any detailed discussion of uses to the papers that follow. The term limestone as herein used embraces all kinds from the variety known as high-calcium limestone, which is composed almost entirely of calcite, to the dolomitic variety, composed largely or entirely of the mineral dolomite. Lime is simply calcined limestone and, in considering the uses of limestone, the uses of lime should also be included, particularly in view of the fact that, in many processes, it is possible to use limestone in either the raw or the calcined state.

Jan 1, 1939

By Henry Mulryan

DIATOMS are microscopic aquatic plants of the order Bacillariaceae. They are unicellular plants with skeletons made up of amorphous opaline silica. The skeletons show highly ornate, complicated geometrical designs. Diatoms live in water virtually everywhere. They are found in clean sea water, brackish water, and fresh-water lakes and ponds. When conditions are right, diatoms propagate by subdivision in huge numbers. Alkalinity, temperature, and the presence of high concentrations of silica in the water largely control diatom life. When the diatoms die the skeletons drop to the bottom of their habitat to form oozes of vary-ing thicknesses. DIATOMITES Diatomite, or diatomaceous earth, is composed essentially of the siliceous remains of the diatoms, although other organic skeletons are also present, especially in sea-water deposits where radiolaria, sponges and silico-flagellates are common. Impurities are generally carbonaceous material, fine-grained silt, volcanic ash and dust, and occasional coarse grains of sand. Diatomites are marine, brackish, or fresh-water, depending upon types of diatoms and their method of deposition.

Jan 1, 1939

By Wilson AF

Gold-silver mineralization at Cracow and Ukalunda in Queensland comprise quartz-filled veins, fissures and breccia zones hosted by propylitically altered volcanics and epizonal intrusions which are strongly fractured. The terrestrial volcanic facies, structural setting, type of alteration and complex mineralogy suggest these deposits are of the epithermal type.The 180 depleted character of the wall-rocks is consistent with the involvement of meteoric waters in convective hydrothermal cells associated with the vulcanism. The Cracow quartzes have remarkably low 6180 values from -2.0 to -3.4 per mil typical. of meteoric hydrothermal systems at high latitude, consistent with the inferred position of Australia during the Permian. 6180 values for the Ukalunda quartzes exhibit a wide range from 5.1 to 14.9 per mil which reflect the mixing of magmatic and meteoric waters, and a steep geothermal gradient.Further stable isotope and geochemical studies are in progress to establish the scale and morphology of the zones of anomalous 6180 and mineralogy in the wallrocks which constitute significant exploration targets.

Jan 1, 1984

By Khosrowshahi S

The objectives of grade control remain unchanged but new methods are being developed to attain them. Since the early-1990s, an improvement in the power of mine site computers has made the geostatistical tools of conditional simulation more accessible. Optimisation of the grade control process on mine sites now involves two stages: optimisation of the sampling regime and optimisation of the interpretation of ore and waste boundaries. Optimisation of the sampling regime first requires an understanding of the nature of the mineralisation and in particular the impact of particle size on the sampling precision. This relationship, termed the Fundamental Error of sampling, enables an optimum subsampling protocol to be defined for the sample preparation and assaying. However, the actual sample collection method, whether drilling or trenching, must be correctly selected and the sampling grid should be optimised. The relative costs and benefits of various alternative sampling methods and grids can be determined using the method discussed. The use of the grade control data can also be optimised. In the past ore and waste boundaries were often defined using a linear interpolation algorithm that smoothed the data (such as polygonal, sectional, inverse distance squared or even kriging methods). Frequently the relative impact of ore loss and dilution could not be estimated. Conditional simulation to generate equiprobable alternative maps (realisations) can now be adopted to address these issues. A transfer function is then used to evaluate the similarities and differences between the maps. The Ore Block Optimisation (OBO¬) process is a transfer function that produces a three-dimensional model of the optimal ore block outlines. This provides a clear guide for the mining geologist to refine and mine. The nature of the transfer function and the inputs and outputs are discussed. In the past, reconciliation has been the `acid test' for any grade control system. Any ore blocking method based on conditional simulation can make use of the exhaustive data set to ensure that reconciliation between prediction and production will improve significantly. The OBO¬ method provides a guide to the mining geologist to ensure that the best ore blocks are mined. Misclassification between ore and waste is reduced, ore loss and dilution are minimised (and are measurable) and ore is optimally assigned to stockpiles of various cut-off grades. These advantages significantly enhance mine profitability and control of the mined grade.

Jan 1, 1997

By Mohammad Kor, David Beattie, Agnieszka Mierczynksa-Vasilev

The selectivity of polymer adsorption in mixed mineral systems is the basis for polymer depression of gangue minerals in flotation. Effective polymer depressants not only reduce gangue mineral recovery, they also have minimal effect on the recovery of the value phase, presumably through targeted adsorption on the gangue phase, and minimal uptake on the value phase. Traditionally, polymer depressant design has been guided by single mineral phase adsorption tests, with affinity and maximum adsorbed amount determined for gangue and value phases separately. However, there is a need to determine the actual extent of adsorption on the gangue phase while in the presence of the value phase. In this work, we report on the development of in situ atomic force microscopy (AFM) imaging for determination of polymer depressant coverage and morphology on mixed mineral surfaces. Our group has previously used AFM imaging on single minerals to connect adsorbed layer characteristics with bubble-particle attachment and flotation outcomes. Two sample types were used to test the methodology: (i) a mixture of two crushed/ground minerals encased in resin; and (ii) a composite mineral sample containing macroscopic regions of three different mineral phases. The samples have been used to probe the selective uptake of two modified dextrin polymers (octenyl succinate anhydride dextrin). AFM images acquired in situ (while all surfaces are immersed in the same polymer solution) of each mineral phase have revealed the natural selectivity of the polymer for the mineral surfaces. In all cases, the polymers adsorb on the all mineral surfaces present, but to a varying extent.

Jan 1, 2014

By Timothy Batchler, Khaled Mohamed

Standing supports have been used in coal mines for decades to enhance roof support capability. Occasionally, standing supports are used to resist the lateral movement of spalled ribs. Researchers from the National Institute for Occupational Safety and Health (NIOSH) are conducting a testing program for standing supports to investigate the effect of lateral loading on their vertical loading capacities and the factors affecting their lateral loading capacities. The Mine Roof Simulator (MRS) was used to determine the response of steel props to vertical and horizontal loadings. Finite element models (FEMs) were developed and verified using the tested steel props. Prop models were used to study the effect of a range of roof and floor materials — gray shale, shale and claystone — on the critical buckling loads of the steel props.

Dec 1, 2022

By E. D. Williamson

DURING the wartime rush to prepare the glass necessary for the needs of our army and navy, the problem of the temperature control of the annealing kilns became most serious. The narrow limits of strain allowable (all the specifications called for less internal strain than the average of the previously used German glass) made necessary a very exact procedure and the methods had to be used on a much larger scale than theretofore. At the Charleroi plant of the Pittsburgh Plate Glass Co., the members of the staff of the Geophysical Laboratory, which was cooperating with the company, had occasion to study the methods available, and reached a number of conclusions (many of them by no means new except in their application) that may interest and assist those who have to meet similar problems in other fields. The following is a short account of the essential features of the system of temperature control evolved, along with a rather abridged statement of the reasons that led to the adoption or rejection of various schemes.

Jan 8, 1919

By W. A. Backofen, D. Lee

The deformation of textured sheet of titanium and several of its all-a (hcp) alloys was investigated with two kinds of experiments: tension testing along different directions in the plane of the sheet, and combined-stress loading along the principal axes of anisotropy (the rolling and transverse directions). Texture and plastic anisotropy were evaluated with pole figures and by measurement, as a function of orientation, of the tensile transverse-strain ratio, or R parameter. The results as a whole can be rationalized qualitatively with the present understanding of deformation mechanisms in titanium. Quantitative agreement between the orientation dependence of tensile yield strength and the Predictions of continuum ANISOTROPY in the properties of engineering materials is more the rule than the exception because anisotropy in structure is so common, and the one generally follows the other. Two broad categories of structural anisotropy are represented by mechanical fibering and crystallographic texture. The former is important in many aspects of fracture.' The latter has more significance for yielding and plastic deformation, theory, using the R measurements, was relatively poor. However, in tension-tension quadrants of the yield-locus diagrams, the difference between theory and experiment was hardly more than 10 pct. The maximum texture-hardening effect was found in a 4Al-1/4O2 alloy to be nearly 50 pct. In the compression-compression quadrant, {1012} deformation twinning prevented the locus from expanding much beyond the Position predicted for isotropic material. With increasing temperature the trend in R was downwards, approaching unity (isotropy) near the a-transus temperature; an accompanying development was large amounts of neck-free extension. which are of special concern in this paper. The tendency has been to view crystallographic texture more as a liability or curio than as an asset. The prominent exception is found in silicon-ferrite sheet for power-transformer cores, which is processed to develop a new optimum texture for high electrical efficiency. Yet it should be possible to find other examples, involving other kinds of properties. More specifically, there is good analytical reason to expect improved combined-stress yielding resistance in suitably textured material,2,3 and it has now been shown by experiment that texture hardening or softening is a potentially useful phenomenon in certain engineering devices and processes.'-I To date, work has included measurements of the transverse (width to thickness) strain ratios in the

Jan 1, 1967