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By Robert S. Dewey

AS a result of drilling operations during 1943, West Texas again added sufficient new oil reserves to replace the oil produced during the year, but failed to maintain its position in currently available reserves because the deeper discoveries will require years for development. Drilling failed to provide the additional oil necessary to meet the increase in current and anticipated market demand. Although 13.3 per cent of the total footage drilled was in wildcat exploration, the ratio of oil discoveries to total wildcats was less in 1943 than in 1942, but comparable to that in 1941. Of the 732 field wells completed, 270 were at Slaughter, 55 at Wasson, 45 at Mascho and 31 at North Cowden. As of Dec. 31, 1943, there were 361 drilling wells including 71 wildcat and 290 field wells; 19.7 per cent were wildcats. It is anticipated that the percentage of wildcats of the total wells will be higher during 1944 than in either 1942 or 1943. Tables 3 and 4 present a three-year comparison of drilling activity and illustrate the downward trend of development that has been in effect during that time. Because of development lag in the deeper Ordovician fields, several years elapse before 2 sufficient number of wells is completed to give a substantial producing rate. As these new oil reserves cost more to find, and will cost more to produce on a barrel basis than the oil marketed during the year, their reserve replacement value to the industry is less in money. Costs While complete costs for deeper drilling are not yet available for analysis, it is evi- dent from the data on drilling rates to comparable depths, contract prices, and general increases in costs, that the cost of drilling has risen approximately 20 per cent during the year. One representative drilling contractor estimates that the average drilling time on a 5000-ft. field well has increased nearly one third and that out-of-pocket costs have increased a dollar per foot. Three major factors contribute to this increased cost: (I) less experienced labor, (2) deterioration in mechanical equipment and expendable material, and (3) increased contract prices. In the past, when there were more drilling rigs than wells to be drilled, some contractors would cut their drilling profit to keep their personnel and rigs working. As this practice is no longer necessary, the contract prices are adjusted upward to assure a profit. On deep and difficult drilling, contracts are let on a cost plus basis. A number of mechanical difficulties have become evident. Inferior quality of steel used in drill pipe and rock bits has added appreciably to drilling time and cost. Contractors are experiencing delay in obtaining repair work and repair parts for prime movers. As the length of drilling time required an shallow-field wells has not increased in proportion to that on deeper wells, it seems that the medium-sized drilling rig is better adapted mechanically than the heavy one to the work imposed. One of the main deficiencies in the heavy rig equipment is inadequate pump capacity. Drilling Mud The increasing amount of deep drilling has emphasized the importance and relationship of good mud to efficient and suc-

Jan 1, 1944

By G. Wendel

Uranium is a naturally occurring radioactive material in the earth?s crust. Geological processes have resulted in concentration of uranium into ore mined for its gold content in South Africa. This uranium is present in the form of discrete particles of uranium minerals, generally oxides, which are normally insoluble. Chemical and physical processes during gold mining and extraction, particularly when carried out in conjunction with uranium extraction and sulphuric acid manufacture, act on the uranium minerals and the radioactive decay products of uranium. This may result insignificant accumulations of radioactive materials in certain parts of the process. There are a number of naturally occurring radioactive materials in the earth?s crust, such as Uranium-235, Thorium-232, andPotassium-40. This paper focuses on Uranium-238, together with its decay products, and how they affect the gold mines. Water plays a significant role in the redistribution of radionuclides, both as a physical transport medium, and as a solvent in which chemical reactions take place.

Jan 1, 1998

By Steve Kral

Mining is a risky business. The cost of exploring for new mineral deposits is high and the success rate of finding one worthy of development is relatively low. And once a deposit is identified, there is no guarantee that it will become a mine. Mining companies have to spend a lot of time and money on due diligence, prefeasibility and feasibility studies, and sustainable development and environmental issues before deciding whether the deposit will become a profitable mine. And then there are the millions of dollars spent in developing the deposit and building a mine. No wonder the mining industry has trouble attracting investment capital. Companies take a large risk in developing reserves and investors take a similar risk in investing in them. So mining companies must be as accurate as possible in determining mineralization that makes it to reserve status. After all, reserves are a company’s most important asset and one of the critical factors analysts and funding sources look at when determining if a mine or mining company is worth the risk.

Jan 1, 2003

By Michael E. Meadows

The results of tests to determine the .regional applicability of four synthetic unit hydrograph models are presented. The SCS curvilinear (Haan), SCS single triangle, Williams and TVA double triangle unit hydrograph models were tested on 271 events from 38 USDA experimental watersheds in 14 physiographic provinces. Though inconclusive due to the limited number of events analyzed, the results indicated a regional tendency for each model, with the SCS curvilinear unit hydrograph method generally performing best overall. It outperformed the SCS single triangle by predicting better shape; they differed less than 2 percent in time of peak and peak rate predictions. The Williams model performed well at Oxford, Mississippi and Coshocton, Ohio, which suggests it may be applicable to surface mined lands within the Northern and Central Appalachian Plateau and Texas coal producing regions. The TVA model is applicable to the Appalachian Plateau, specifically the Cumberland Plateau. A second test using only the SCS curvilinear unit hydrograph on 11 small watersheds and 50 events was conducted to investigate the effect of the excesss rainfall pattern on simulation results. A Green and Ampt infiltration model was coupled with the SCS unit hydrograph model to determine if peak rate and timing errors noted in the regional test could be minimized with an alternate to the SCS curve number model for determining infiltration losses. The results confirm the curve number model is the better approach to determining the excess rainfall pattern for unit hydrograph simulation.

Jan 1, 1983

By E. C. Lane

During the past 15 years the Bureau of Mines has made and published several hundred analyses of typical petroleums and has developed a system of interpreting the analyses and of classifying crude oils. In describing crude petroleum frequent reference is made to the "base" of the oil, a usage the petroleum industry has found convenient. As part of its general study of the characteristics of crude oils, therefore, the Bureau of Mines has developed a system of classifying them according to "base." This system as first published in 19274 was limited to four classes and in its original form is no longer considered adequate. Since the system was first published the Bureau has analyzed a large number of crude oil-, including representative samples from nearly every important producing field in the world, and has found that the system of classification could be revised and amplified to advantage. The revised system is presented herein. Bulletin 2916 states that many oil producers and refiners use the word "base" much as it is used in pharmaceutical work. For example, the "base" or "basis" of an ointment or salve is the fatty material (lard, petroleum, or lanolin) used as a vehicle or carrier for the active medicinal principles. Apparently many of the pioneers in the petroleum industry considered crude oil similar in nature to these medicinal products in that it consists of a semisolid, nonvolatile base and 1 volatile portion can be distilled off to make gasoline, kerosene, and other products. Many crude oils when chilled slowly deposit a waxy material (paraffin); this fact may have been one reason for the use of the term "paraffin base" in referring to such oils. Almost all of the petroleum first discovered in the United States was of this nature; not until the oil industry was extended to California and along the Gulf coast was petroleum found that contained no wax but apparently did contain asphaltic material Accordingly, these oils were known as "asphalt-base" oils. The use of this term, however, seems unfortunate, as better-grade oils of this type contain little if any asphalt; the descriptive term "naphthene base" now seems to be a more desirable term than "asphalt base." The term "intermediate base" is also used commonly in referring to oils intermediate in oharacteristios between those of paraffin and naphthene base.

Jan 1, 1935

By K. A. Lewandowski

Binders have been suggested as an aid for agglomeration to improve copper recovery in heap leaching operations. However, it has not been established if the use of binders would negatively affect the solvent extraction process, which is used to purify the pregnant leach solution from the heaps and remove any contaminants. Such negative effects would lead to an increase in processing costs or a decreased in copper production. The controlled studies reported here have shown that some binders (a polyacrylamide and a waste treatment additive) did not interfere with the solvent extraction process. Other binders (a polyvinyl acetate emulsion and tall oil pitch) negatively impacted copper solvent extraction and, therefore, should not be used in copper heap leaching plants.

Jan 1, 2009

By Dick T. Atkinson

Due to improvements in the safety of other aspects of mining (primarily in roof control), haulage related accidents, particularly rail haulage accidents, are about to become the most common category of hazards causing death and injuries to underground coal miners. The major causes of these accidents are collisions between vehicles, men caught between rib and trip or between cars, derailments, and runaway cars. Such hazards can be greatly reduced if the motorman has the capability to selectively couple and uncouple cars from the cab of the locomotive, to transmit braking intelligence to the coupled cars, to determine if the trip is intact, and if brakes are automatically applied in any uncoupled car. These capabilities can be provided through an improved coupler system, designed and built by Foster-Miller Associates under a Bureau of Mines contract. Early in the program, a survey of rail haulage patents and literature was conducted. Manufacturers of couplers, mine cars and braking systems were contacted and information relevant to the remote control mine haulage application was collected. From this information evolved a working specification and a design concept. The key elements of the specification, shown in Table I, are the result of a detailed tradeoff study and considerable thought given to the specific problems encountered in the mining environment. A brief explanation of each element is as follows: Automatic Coupling - The couplers operate similarly with most already in underground use - they latch together when a trip is backed into a car intended for coupling. Remote Uncoupling - From the locomotive, the motorman can decide how many cars are to be uncoupled, operate the appropriate controls, and the desired coupler is opened.

Jan 1, 1977

By Qidong Zhang, Yongsheng Song, Wenjuan Li, Guiying Zhou, Kun Song

"Molybdenum is a very important rare mineral resources, which exists largely in oxidized ores and sulphide ores in nature. About 99% of metallic molybdenum comes from molybdenite. The talcose molybdenum resources are abundant but the resources utilization is low, because the talc is naturally hydrophobic and the floatability of talc is similar with molybdenite, which lead to difficult separation by flotation. Talc is easy entry into concentrate in flotation which can cause the content of MgO overhigh, therefore the molybdenum concentrate grade can not meet the industrial requirements. Thus the utilization level of talcose molybdenum resources has been restricted greatly.The adsorption of water on talc and molybdenite surfaces and natural floatability of minerals were studied by density functional theory method. The results showed that molybdenite and talc were layered minerals which exhibited similar surface wettability and H2O molecule prefers to stay with water rather than the minerals surfaces. N2 is adsorbed on talc and molybdenite surfaces more easily than H2O. The interaction and flotation behavior were studied by SEM and flotation experiments. The reason why talc interferes with the flotation molybdenite has been revealed. The agglomeration between molybenite and talc was caused easily in neutral or acidity solution, and it was dispersing between molybenite and talc particles in alkaline solution. The flotation results showed that good floatability of talc was the key factor causing a low grade of concentrate in alkaline solution. Thus, it is the key factor to enlarge floatability difference between molybdenite and talc.INTRODUCTIONMolybdenum is a kind of important rare metal and strategic reserve resources (Zhitao Y et al, 2016a). Due to excellent characteristic, such as high melting point, good thermal property and et al, it’s widely used in metallurgy, machinery, chemical, aerospace, and many other areas. It has become an indispensable metal in modern industry. Molybdenum generally exist in the form of molybdenite which is a kind of mineral with excellent natural floatability. Talc is a kind of typical hydrous and layered magnesium silicate minerals (Beattie D et al,2006a), which is one of the most common gangue mineral of the platinum group metal ores and metal sulfide ores (Tao L et al,2011). Due to its good native floatability, talc is easy entry into the concentrate product with foam in the process of sulfide ore flotation (Kelebek S and Smith S, 2006b), which resulted in decreasing concentrate indexes. Not on that, the high-content MgO of concentrate will also produce a series of adverse impact to the subsequent smelting (Lotter N O et al, 2008). Therefore, it is difficult to separate talc from sulfide ore concentrate effectively."

Jan 1, 2018

By Balu E. George, Subhadeep Banerjee, Shailesh R. Gandhi

"A three-dimensional analysis of laterally loaded helical piles installed in cohesionless soil is presented. Finite Element Analysis was conducted using commercially available Plaxis 3D AE version, assuming Mohr-Coulomb failure for soil. Pile is modelled as plate elements with a single helical blade attached to a hollow shaft. The ultimate load for various configurations is examined considering deformation criteria. The Bending Moment distribution and maximum lateral deflection are also discussed. It was observed that the ultimate lateral load carrying capacity increased by presence of helical blade and the maximum deflection also got reduced. The diameter of the helical blade was found to have significant effect on the lateral deflection, maximum bending moment and the ultimate load. However, the observations from the study suggest that the presence of helical blade seizes to produce considerable effect after a certain depth. Difference in failure pattern with regard to the distribution of soil resistance observed for different geometries considered for numerical analysis are also touched upon.INTRODUCTIONHelical piles or screw anchor piles have gained popularity due to fast installation, instant use, and other advantages over the traditional piles. They are usually used to support structures like solar panels, light houses, and other light structures which are subjected to uplift loads. However, such structures are often subjected to significant lateral loads as well. Under lateral loads, the response of helical piles can be different from that of a conventional pile due to the presence of the bearing provided by the helical blade. However, the proper design remains a concern due to lack of work carried out on the lateral capacity of helical piles.The lateral performance of helical piles is significant because they can act as efficient alternative to conventional piling systems in many applications.The lateral load capacity of screw anchor piles with different number of helices were examined by Mittal et al. (2010) by experiments in sand. They found that the lateral load capacity of piles increases with addition of helical blades. Prasad and Rao (1996) examined the lateral capacity of helical piles in clay by experiments on model piles and found that the lateral capacity of helical piles were more than that of the straight shaft piles. It was observed that the lateral capacity increase with embedment depth and shear strength of soil. Sakr (2009) studied lateral performance of two section helical piles in soft soil. The investigation by Prasad and Chari (1999) reported that the pressure distribution across the diameter is not uniform for circular piles, but it is maximum at the centre and almost zero at the two edges.Puri et al. (1984) after conducting model tests on single-helix, two-helix, and three-helix anchors installed in sand, proposed a mathematical model that was fashioned after Matlock and Reese’s elastic theory model. Elkasabgy and Naggar (2015) investigated he lateral performance of full scale large capacity helical piles in structured cohesive soils and reported the modulus of sub-grade reaction to be non linear."

Jan 1, 2017

A paper presenting an overview of legislative and best practice approaches to the management of OHS&E and business risk for Australian tunnelling operations. Best practice can be achieved in Australian tunnelling through ærisk awarenessÆ by decision-makers and line personnel. This will identify problems before they occur and lead to implementing controls appropriate to avoiding loss throughout the life cycle of the underground opening. The author draws on legislative approaches from all Australian states together with practical experience from risk management and risk engineering work from six recent tunnelling projects. This describes a process that:commences with concept risk assessment,involves quantification of major hazards,conducts assessments of operating risks, andleads to implementation of an integrated management system that keeps construction activities connected with the controls identified in the design and planning phases and minimises the losses sustained as a result. Key points addressed include:where the industry is going with respect to risk û methods and considerations,how tunnelling risks are perceived by the industry and legislation,how tunnel constructors and owners can minimise exposure by using proper risk engineering ætoolsÆ, andreflections on best practice methods for transferring knowledge from designers to contractors/operators.

Jan 1, 2008

By NA NA

In the third of its features on the new owners of the British coal mining industry, Mining Technology reports on the newest company in the field, Midlands Mining.

Jan 2, 1997

By H. Kudelka

Copper electrowinning at Duisburger Kupferhuette was introduced in March 1975. The electrowinning plant has a capacity of 10,000 mT of copper cathodes a year. The cuprous oxide feed material is an intermediate product of the treatment of the leach solutions, originating from chloridizing roasting of pyrite cinders. This material is characterized not only by a wide spectrum of accompanying impurities, but also by an unusually high level of precious metals. As the priority set was the production of high-purity cathodes. there was a need for developing a process which would be suited to treat complex leach liquors . The process adopted consist s of an oxidizing leach in spent electrolyte, followed by two- stage purification, By this means. a low- acid pregnant copper electrolyte is obtained free of elements detrimental to copper quality. Electrowinning is carried out at a current density of 200 A / m2 in the presence of 10 g/l zinc. The electrowon copper has a conductivity of at least 101.4% lACS and a softening temperature not exceeding 200°C, which makes it a suitable product for continuous casting and dip ?forming.

Jan 1, 1977

By AIME AIME

IF the observation of our British friends is true that Americans put new records in bigness above everything else then the 150th meeting of the Institute was not the grand success it seemed to be. Just why the attendance slumped a little this year is anyone's guess, but the favourite explanation seemed to be that half the country is planning to come to the New York World's Fair this summer and that two trips from the hinterland to the me- tropolis, with another to San Francisco of course, can hardly be justified with the present condition of the stock market and the prices of the products of our mines. Certainly, some were pre- vented from coming too by the epidemic of respiratory afflictions that was rampant in February. Unfortunately. several succumbed after they had reached New York.

Jan 1, 1939

By Foster Fraas

The Bureau of Mines investigated a method for calculating values of adsorption energy; the goal was to devise an equation consistent with experimental data accumulated in the investigation of adsorption as related to ore separation processes. Numerical identification of the constants of a previously formulated equation provided an equation by which values of adsorption energy could be calculated. Values thus calculated checked with those obtained by calorimetric measurement.

Jan 1, 1965

By M. K. Pelser

The purpose of this paper is not so much to provide a scientific study of the selection process for the perusal of other psychometrists or industrial psychologists?the purpose is to provide line management with a practical, relatively user-friendly guide to fair and scientific selection. The main areas that are to be covered are: ? Why fair and scientific selection? ? Job analysis ? The job requirement?selection technique circle ? Assessment centres in the mining industry?the Tavistock Collieries Ltd experience. Why fair and scientific selection? Seen from a line manager?s perspective, fair and scientific selection should be pursued for two main reasons: ? to remain within the ambits of the law ? to maximize the probability of selecting the potentially most productive and efficient candidate for the job.

Jan 1, 1997

By David J. White

The decreasing availability of land in urban areas, and the increasing demand for urban development is leading to the construction of taller and heavier buildings at increasingly marginal sites. Such structures usually require founding at depth and modern construction methods are making the economics of piled foundations ever more attractive (Salgado, 1995). However, the urban environment is not suited to pile driving. Conventional dynamic installation techniques (i.e. drop hammer or vibro-piling) induce vibrations and settlement in a zone close to the pile, and cause noise and dust pollution. Damage to existing structures resulting from pile driving vibrations is not uncommon (Tomlinson, 1986).

Jan 1, 2000

By Joseph L. Ritchey

The Trail Lake RARE II area comprises 1,300 acres (526 ha) in Lassen and Plumas Counties, California, adjacent to the Caribou wilderness. No mining claims, prospects, or quarries are reported within the study areas, and no evidence of potential mineral deposits was found during a field reconnaissance. Quaternary basaltic lava flows uniformly underlie the area. INTRODUCTION The Trail Lake (No. B5-095) RARE II further planning area occupies 1,300 acres (526 ha) adjacent to the Caribou Wilderness in Lassen and Plumas Counties, California. Susanville is about 30 mi (50 km) east and Chester is about 17 mi (27 km) south of the study area. Access from State Highways 44 and 36 is provided by well-maintained gravel roads.

Jan 1, 1981

By David R. Delling

Introduction In 1967, Tenneco acquired Kern County Land Co. The primary reason for the acquisition was to obtain Kern's agricultural, manufacturing, and oil interests. Included in the Kern portfolio were the core of Tenneco's present sodium leases in Sweetwater County, WY. This lease base has been ex¬panded and now consists of 62 km2 (24 sq miles). Beneath this property lies more than 500 Mt (550 million st) of economic trona ore. Following the Kern acquisition, Tenneco continued exploration and feasibility studies concerning the trona leases. The effort was accelerated in 1976. Tenneco was attracted to trona because of the favorable lease position it held, the growth rate of the Wyoming industry during the 1960s and 1970s, and the prospects for a long-term, stable business enterprise. The reserve picture was certainly attractive to a company long accustomed to the never-ending struggle to replace oil and gas reserves. In 1978, Wyoming was a boom area that had experienced rapid growth for a number of years. Unemployment was very low and vacant housing nonexistent. The prospects for soda ash were somewhat different in the 1970s than now. But it was recognized even then that a new producer would have a challenging task to compete in this business. Tenneco knew the capital burden required to build a grassroots facility during inflationary time, would have to be offset elsewhere Since labor and energy are the dominant direct costs in mining trona and producing soda ash these factors have always received a great deal of attention. Contracting and permits Environmental monitoring on the site began in late 1977. With the already mentioned considerations in mind, engineering began by mid-1978. Brown & Root Inc. was selected as the general contractor for the project. S. A. Scott & Co. was the engineering subcontractor for the mine shafts, hoists, ventilation system, and miscellaneous mine facilities. Frontier-Kemper was awarded the contract for sinking the two mine shafts. Acquisition of numerous federal, state, and local permits occupied all of 1978 and 1979. The Wyoming Industrial Siting Permit, which addresses socioeconomic issues, drew the most public interest. Siting issues were all satisfactorily resolved by negotiating reasonable stipulations with various local governmental units, school districts, and the like. Site location The Green River project location is not truly remote. It is located within 5 km (3 miles) of Interstate 80 and only about 32 km (20 miles) west of the city of Green River. Nevertheless, a substantial investment had to be made in communication and utility links to the site. These included: • A 14-km (8.5-mile) rail spur connecting with the Union Pacific Railroad at Bryan, WY. This spur has four bridge structures including one crossing Interstate 80. Most soda ash is shipped by rail, and coal is received over this line as well. • A paved 5-km (3-mile) roadway connecting to Interstate 80. • A powerline extension of about 27 km (16.5 miles), along with two new substations. • A 24-km (15-mile) waterline connecting the plant to a pump station on the Green River. The site is located on gently sloping terrain at an elevation of about 2.1 km (6800 ft). Ground conditions are good for construction. Weathered bedrock lies near the surface in most places. Geology The general geology of the Green River Basin has been well described previously. Tenneco's ore is in several superimposed evaporate beds. But the bulk of it is present in Bed 17, located about 457 m

Jan 10, 1985

To the members of The South African Institute of Mining and Metallurgy We have audited the annual financial statements of The South African Institute of Mining and Metallurgy set out on pages 451 to 460 for the year ended 30 June 2002. These financial statements are the responsibility of the Institute?s Council. Our responsibility is to express an opinion on these financial statements based on our audit. Scope We have conducted our audit in accordance with statements of South African Auditing Standards. Those standards require that we plan and perform the audit to obtain reasonable assurance that the financial statements are free of material misstatement. An audit includes: ?examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, ?assessing the accounting principles used and significant estimates made by management, and ?evaluating the overall financial statement presentation. We believe that our audit provides a reasonable basis for our opinion. Audit opinion In our opinion, the financial statements fairly present, in all material respects, the financial position of the Institute at 30 June 2003 and the results of its operations and cash flows for the year then ended in accordance with South African Statements of Generally Accepted Accounting Practice. Auditors 29 July 2003 Council?s approval of the annual financial statements The annual financial statements for the year ended 30 June 2003 set out on page 451 to 460 were approved by the Council on 26 July 2002 and are signed on its behalf by:

Jan 1, 2003

By S. Steinlechner, G. Schneeberger, J. Antrekowitsch

Due to always getting stricter environmental legislations as well as increasing land filling fees the efforts for treating residues from metallurgy are continuously increasing. In case of filter dusts from metallurgical industry, the high zinc bearing electric arc furnace (EAF) dusts or also dusts from secondary copper industry are important sources for the recovery of secondary zinc oxide. Because of low capacities for secondary zinc concentrates (like Waelz oxide) in primary zinc metallurgy, the upgrade of such concentrates to a quality that meets the requirements of high quality (technical) zinc oxide becomes more and more important. This would open the opportunity to break into new markets and use it for example directly in electrolytic galvanizing. Therefore this paper will summarize possibilities for an elimination of halogens from secondary zinc oxides. Furthermore selective volatilization trials, with a synthetic mixture according to the analysis of Waelz oxide, were carried out to remove impurities to achieve an upgraded product quality.

Jan 1, 2011