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By Yerkezhan Madenova, Kairat Kalmurzayev

This study intends to demonstrate the engineering application of ground penetrating radar (GPR) that would enable site engineers to prevent the high cost of blind drilling. At the tailing dump located in Zhairem Mining and Processing Plant, the challenge of sheet pile driving is encountered due to the indefinite watertight clay layer deposition depth that serves as a protective layer against groundwater contamination. A numerical model of the soil underlying the tailing dump is built using the existing hole data to compare and confirm the existing geological cross sections for three profile lines along the south and southeast parts of the tailing dump. GPR is employed to investigate the subsoil geological structure and detect the watertight clay layer deposition. On the basis of radargrams tied to the existing borehole data in the numerical model, 21 drill hole locations are suggested to assess and confirm the clay layer depth along profile lines at the tailing dump. The drilling results of the suggested holes confirmed the expected depth of the clay layer. It is concluded that GPR is a practical and economic subsurface mapping method that can prevent the high cost of blind digging of the ground and orient the drilling operations effectively.

Jan 12, 2023

By Liaqat Ali, Robert Chapman, Asghar Ali, Mohammad Tahir Shah, Seema AnjumKhattak, Mohammad Farhan

Alluvial gold is abundant in the Quaternary deposits of the Kabul and Indus rivers in District Nowshera, Khyber Pakhtunkhwa, Pakistan. Understanding the provenance of alluvial gold using morphology and elemental composition could be helpful in developing an exploration strategy of regional benefit. Detailed morphological studies of gold grains revealed high flatness index values which are indicative of a distal source. Compositional studies of 58 gold grains using SEM and EMPA showed broadly similar Ag ranges (1– 15 wt%) for each sample and occasional Cu values in individual gold particles to 0.4 wt%.Whilst the Ag profile is not diagnostic, the Cu values are compatible with derivation from either porphyry systems or ultrabasic rocks. The complex geology of the drainage catchments could host gold mineralization of other styles, but larger sample suites would be required to refine the current interpretation to establish whether particles which are simple Au-Ag alloys could be derived fromorogenic or epithermal sources. This scoping study has demonstrated that the compositional and morphological studies of gold grains are useful in providing information regarding the nature and location of the source of placer gold in areas where there is limited information on the nature and location of in situ mineralization.

Oct 6, 2020

By Malcolm T. Wane

The subject matter of this paper, "Applied Rock Mechanics?," has its genesis in a recent field trip taken by the author. A more or less standard question asked at the mines visited was "How are you using the principles of Rock Mechanics to assist you in maintaining an efficient, safe, and competitive mining operation?" The question was couched in a number of different forms, but the intent was to determine whether or not a general theory based on reason and the scientific method was applied or whether the alternatives of tradition, intuition, ?common sense', revelation, ?shotgun methods' or authoritarianism were invoked. Perhaps two responses to this query will be illustrative of the general nature of the replies. At operation XYZ an extension to the known ore body has been found. The extension is of large enough size and grade that a mining scheme using load-haul-damp techniques is envisaged. Since this represents a departure from the present mining scheme, questions have arisen regarding pillar sizes, room and entry sizes and possible support requirements. A task force has been set up to expeditiously plan for these things and write the necessary specifications and requirements. The fundamental question was posed to members of this group.

Jan 1, 1971

By Theodore H. Eyde

In 1971, the Minerals Division of The Superior Oil Company acquired exploration rights to an unpatented claim group in the Superior (Pioneer), Arizona mining district, lying west of the Concentrator fault. This major post-mineral fault displaces the Magma vein-fault, which is mined in the Magma Mine at Superior, Arizona. The Magma vein-fault and the enclosing section of pre-mineral rocks consisting of Paleozoic and younger Precambrian sediments and diabase, is overlain by a thick section of post-mineral rocks, consisting of the Gila conglomerate, the Apache Leap dacite, and the Whitetail conglomerate. Geologic information on the thickness and attitudes of the rocks obtained from previous diamond drilling indicated that the section of post-mineral rocks might be from 3,000 to over 4,010 feet thick in the target area. (Figure 1) The Magma vein-fault is a steeply dipping vein which has produced nearly a billion dollars of copper, zinc, silver, and gold. It has been mined continuously for nearly 10,000 feet along the strike and nearly 5,000, feet vertically down the dip. It ranges from less than a foot to over 50 feet wide and contains sulfide mineralization con¬sisting of pyrite, chalcopyrite, bornite, and chalcocite.

Jan 1, 1973

By Stanley Kesler

The first of two initial 650-mw units of the Paradise Steam Station, located on the banks of the Green River in the south-central portion of the western Kentucky coal basin, is scheduled for operation in late fall of 1962. Location of the site is shown on the map of figure 1. This plant will be the eighth, large-capacity,, modern station built by TVA in a series starting with Johnsonville, operated first in 1951. During that period of 10 years,, unit sizes have increased from a capability of 125 mw to 500 mw at the recently completed Widows Creek Unit 7 addition and at Paradise to 650 mw. This new unit will take its place in a power system that serves an area of some 80,000; square miles with a present installed capacity of over 12,000 mw. Upon completion of the Paradise units and other additional hydro and steam units presently under construction, the system capacity will have reached over 15,000 mw. Projected load estimates indicate that this system will provide a margin' of slightly under 10 percent of dependable capacity above peak demand at that tire. One Paradise 650-mw unit at that time will represent approximately 4 percent of the total system installed capacity.

Jan 1, 1962

By B. H. Kim, P. Zhang, M. A. Van Dyke, D. Su, H. Dougherty

The National Institute for Occupational Safety and Health (NIOSH) has been evaluating longwall mining-induced strata fractures and their impacts on casing stability of Marcellus shale gas wells located in longwall pillars. To understand the extent of overburden fractures after longwall mining, NIOSH researchers drilled a postmining corehole into the fractured strata above the Pittsburgh coal seam longwall gob. Knowing the extent of the fracture zone height will help gas operators minimize the hazards of drilling into longwall gobs. The core was retrieved from the surface down to the top of the gob void. Various fractures were encountered varying from 35 to 64 degrees, depending on lithologic type and relative closeness to the gob. The longwall panel dimension was 457 m wide and 3657 m long, in which the total fracture zone height was found to be at 141 m and the hydraulic connected fracture zone at 87.7 m above the top of the Pittsburgh seam. In addition to core drilling through the gob, FLAC3D modeling was also used to simulate the formation of fracture zone and the orientations of longwall-induced fractures. This study provides much-needed evidence on the fracture zone of Pittsburgh seam longwall gobs to help gas operators avoid potential hazards associated with drilling through highly fractured zones

Mar 2, 2022

By T. Deschaines

Raman Spectroscopy has become increasingly popular as a method to rapidly identify and characterize minerals, gem stones and other inorganic materials. Raman spectroscopy provides valuable information about the chemical bonds and structure of materials. In fact, the peak locations and intensities observed in a Raman spectrum can often be used to confirm the presence or absence of particular species in a sample. Some modern Raman spectrometers have been designed to analyze samples less than a micron in size while others are designed to rapidly screen bulk material with no sample preparation. Recent advances in software and automated instrument control have greatly reduced the complexity of Raman spectral analysis and provide an easy-to-use tool for analyzing minerals. We will describe the application of several multivariate statistical analysis techniques that have been developed to make use of the spectral libraries. In these techniques the spectrum is treated as a vector and sophisticated mathematical techniques are used to determine which spectral representations in the reference library best match the spectrum from the sample. The DXR Raman microscope was used to 1) Identify minerals by spectral searching, 2) Identifying several species in a sample using multi-component analysis 3) Mapping different species in an aggregate sample and 4) identifying inclusions in a sample.

Jan 1, 2010

By P. Zhang, D. W. H. Su, M. Van Dyke, H. Dougherty

To provide critical scientific data and engineering guidelines to federal and state regulatory agencies as well as the coal and gas industries, the National Institute for Occupational Safety and Health (NIOSH) initiated a Gas Well Stability Research Program in 2016. This paper summarizes the critical scientific data acquisition, interpretation, and modeling by NIOSH regarding the stability of unconventional shale gas wells influenced by longwall mining. Currently, NIOSH is the only organization in the U.S. conducting such fundamental and impactoriented research, which receives input and collaborations from MSHA, PADEP, WVDMS, OHDNR, the coal industry, and the gas industry. Results from the NIOSH field instrumentation programs—which include surface, subsurface, and underground instrumentation—and the parallel three-dimensional numerical modeling programs indicate that, under shallow and medium covers, the measured horizontal displacements within the abutment pillar are one order of magnitude higher than those measured under deep cover. Casing couplers are found to play an important role in longwall-induced casing deformations. Cementing alternatives are found to have significant impact on longwall-induced casing stresses and deformations. Measured 60-arm caliper logging results are in good agreement with three-dimensional computer simulation results. Engineering guidelines on longwall-induced deformations, casing and cementing alternatives, gas well setback distances, as well as risk assessment strategy are proposed.

Mar 2, 2022

By J. F. Childs

Montana consists of an Archean crystalline basement overlain by Proterozoic through Cenozoic sedimentary rocks. Igneous rocks range in age from Archean to Pleistocene; the most voluminous magmatism and volcanism occurred during the Late Cretaceous and early Tertiary. The state can be divided into three tectonic provinces whose deformational styles are a function of different bedrock responses to Late Cretaceous-early Eocene compressional tectonism. Several long-lived structural zones have been periodically reactivated since the Precambrian, and were the sites of recurrent magmatism. Regional gold distributions are strongly influenced by the tectonic provinces and structural zones. Lode gold systems in Montana occur in diverse geologic settings resulting from a complex interaction between structure, magmatism, and sedimentary depositional processes. Reserves or resources are known for 19 significant lode gold systems, and additional unannounced discoveries have been made recently. Mineralization ranges in age from Archean to Tertiary. The influence of long-lived structures is apparent at both the regional and deposit scale, and in some cases multiple mineralizing events have been superimposed upon one another. Most Montana gold systems have a direct spatial and genetic association with Late Cretaceous through Oligocene igneous rocks. However, the importance of sedimentary rocks and associated depositional processes should not be underestimated.

Jan 1, 1993

By Robert H. Hooff

The Vor-Siv Dewatering and Classifying Unit was developed by the Polish Coal Industry because of a need for a unit that would dewater and classify high volumes of solids in water slurry. To be practical, the unit needed to be relatively small in size, simple in design, involve low operating costs, and be able to give a dewatered product of less than 30% moisture. The answer to the above mentioned criteria was the Vortex Dewatering Sieve or, as we refer to it, the Vor-Siv. The original installation of the unit, as we know it today, began in 1963 when the Pols installed the unit in a full scale pilot application. By 1966, at least 30 of these units were installed throughout the Polish Coal Industry. This equipment was originally introduced in the United States in 1966 at the Fifth International Coal Preparation Meeting in Pittsburgh, Pennsylvania. The first installation in the United States was not achieved until 1970, when Mr. Fred Sachs of The Valley Camp Coal Company, Triadelphia, West Virginia, installed a Vor-Siv in a retrofit application. To date, there are 36 Vor-Sivs installed in this country and 29 in the process of being installed or delivered.

Jan 1, 1976

By A. L. Crandell

The Cortez Mining District has had a long history of mining activity dating back to 1862 as previously reported (1) (2). More recently Cortez Gold Mines (i) has operated a cyanide leach, counter current decantation (CCD) recovery gold mill from January 1969 to February 1976. This type of plant has been standard in the U.S. for treating higher grade finely disseminated gold in Carlin type ores. The mill was initially operated from 1969 to 1973 at 1520 tonnes per day on oxidized ore from the Cortez ore body. Starting in 1973, the mill was operated at 2050 tonnes per day on softer, less oxidized, high clay ore from Gold Acres which is located 13 kilometers to the west of the Cortez installation. In February of 1976 the oxidized portion of the ore body at Gold Acres was depleted and the mill ceased operation. Successful heap leaching of the lower grade portion of the ores was practiced at both Cortez and Gold Acres to supplement the milling operations. Much valuable experience was gained in the operation of these two heap leaching programs and is well described in an earlier publication (3). Releaching of the ore heaps at Gold Acres and Cortez was continued with a limited crew from 1976 to 1979.

Jan 1, 1986

By F. Mielli

Over the last three years there has been an increase in mining congress and conferences focusing on water management. Water in mining is a key concern for mine managers and operations, and we are now seeing this operational dilemma escalated to the level it deserves. According to Frost & Sullivan research, mining water and wastewater treatment and its related technologies will be a U$3.6 Billion global market in 2016, which translates the importance of this issue. Looking at the current mining trends, some factors increased the importance of water in mining operations, including: ? Future mining investments will be located in geographical locations where water is scarce (water stressed areas) ? A decline in grade will increase the intensity of mineral processes and therefore increase the use of the water ? Increased sustainability and regulations will extend the control/monitoring of water during the entire mine life cycle representation of the mine water flow system. A water balance has several benefits/objectives in a mine operation: ? Mine planning/simulation of mining scenarios/climate change Production optimization ? Minimizing strategic and operational risks ? Social license to operate ? Water-smart mine planning ? Target: water neutral mines ? Benchmarking within and between sites ? Sharing knowledge/technology transfer ? Reporting/communications ? Permitting/Compliance

Feb 23, 2014

By Joel K. Waterland

The Homes take Mining Company at Lead, South Dakota has a yearly production of 1,868,741 tons of ore produced from horizontal cut-and-fill stopes and timber cut-and-fill stopes. This production, in addition to the necessary development (drifts and raises), requires 5,168,271 feet of drilling annually. The rock for the most part consists of quartz; mica schist; and cummingtonite schist; and must be considered as relatively hard. Penetration rates average about 15 inches per minute using an operating air pressure of 100 psi. The rock is tough, rather than brittle, and dulling occurs quite rapidly. The average regrind period is approximately 19 feet per regrind using a 1-7/16 inch carbide bit. At the present time, all drilling is accomplished with 2-5/8 inch bore airleg mounted drills, and 2-3/4 inch and 3-inch diameter bore -stopers (raising only). These machines are all direct striking, with 4-1/4 inch chucks. 7/8-inch hexagonal carbon drill steel with forged collars are used in conjunction with 1-7/16 inch multi-use, threaded, carbide bits. 62,793 rods, and 16,234 bits are used to maintain the yearly production. The number of rods noted are the rods that were sent: underground, both new and reconditioned.

Jan 1, 1963

By Francis J. Quinn

The Natural Gas Act, of 1938, which put interstate pipelines under the jurisdiction of the Federal Power Commission, did not place a protective competitive shield around such companies - nor does any provision of the act guarantee them a profit. Natural-gas pipelines are competitive with each other and also with the coal and oil industries. Gas distributing companies must compete not only with the coal and oil industries, but also with the electric industry. Natural gas has captured markets from oil, which had taken them from coal. Oil men contend that gas prices have: been, held to an artifically low level by regulation. The electric industry is moving into the space-heating market, which pleases the coal people because the coal industry's largest customer since losing the railroads to dieselization has been the electric companies. The coal industry is attempting to monopolize the industrial and electric generating market through government intervention, and this is being done under the guise of concern for the national welfare through advocation of a "National Fuels Policy purporting to, further the cause of fuel conservation. Such a policy is contrary to American principles and would result in the individual's loss of freedom of choice and ultimately, in less reserves of preferred fuels because of diminished exploration efforts.

Jan 1, 1961

By Mahmood B. Mirza

The geology of the Gulf Coast Salt domes has been extensively studied by Kupfer (1,2,3,4,5), Atwater (6,7), Balk (81, Hawkins (9), and Wharton (10). dominant geological feature of Southern Louisiana is the Gulf Coast Geosyncline. The axis of this geosyncline corresponds with the present day coastline of Texas, Louisiana, Mississippi, Alabama and Florida. This geosyncline has been continually subsiding since Cretaceous times and receiving large deltaic accumulations of sediments from Central North America. These accumulations progressively thicken toward the South. In the vicinity of the Coast, these sediments are reported to be about 40,000 feet thick. Another dominant feature of the region is the large number of salt domes scattered along the Gulf Coast (fig. 1). Typically, these domes are roughly cylindrical in shape, 1 to 5 miles in diameter, and extend to more than 20,000 feet in depth. It is hypothesized that these domes are derived from the thick Louann salt formation lying below the deltaic sediments. Due to its low specific gravity and buoyancy, the salt layer protruded upwards plastically and pierced the overlying strata. As a result of this upward flow, the adjacent strata are locally lifted upwards, creating excellent traps for petroleum accumulation.

Jan 1, 1979

By Francois E. Heuze

This paper summarizes the geomechanics programs conducted in two hard rock underground mining operations in the Western United States, between 1966 and 1981. The two projects were directed towards understanding the behavior of the rock masses, at the scale of the caverns. To this end, the emphasis was put on large scale field measurements, complemented by limited laboratory testing. The results of these observations were used to build realistic finite element models of the underground chambers. In the marble mine, at Crestmore, California, the models were applied to the structural optimization of the room-and-pillar pattern. In the granite mining, at Climax, Nevada Test Site, the models explained some unusual stress changes observed during excavation. Based on the large number of geomechanical techniques employed, specific conclusions and recommendations are offered regarding the quality, applicability, and usefulness of the various methods. The two case histories clearly indicate chat numerical models are extremely useful for a detailed understanding of the structural behavior of mine openings. To be realistic, these models must be based first and foremost on large scale field observations. The lessons Learned on these two projects also are directly applicable to the design and analysis of nuclear waste repositories in hard rocks such as basalt, granite, and welded tuff.

Jan 1, 1982

By David G. Thompson

There are basically two commonly used methods of drying washed coal. They are mechanical drying (sometimes called dewatering) and thermal drying. The common methods of mechanical drying are by using vibrating screens, cross flow screens, sieve screens or Vor-Siv, vacuum filters and centrifugal dryers. With thermal drying, the common types include direct fired fluid bed, rotary drum, flash or suspension, vertical tray or cascade continuous carrier or vibrating fluid bed dryers and hollow screw dryers. In the past, it has more or less been a general rule that any time the total product is being washed, both mechanical and thermal drying was required. The reason for this was that a product moisture of 3 to 4% was required and thermal drying was and is the only practical method by which this can be accomplished. With the advent of air pollution controls and the ever increasing concentration on dust elimination, a 3 to 4% moisture product is no longer practical in either the preparation plant or in the processing plants which utilize the coal. Under the new standards, it is desirable to have a product with a 6.5 to 7% surface moisture. With this moisture range, dusting, due to handling, will bc kept at a minimum.

Jan 1, 1975

By E. A. Wieselmann

In 1970 Texasgulf (Australia) introduced natural gamma radiation logging of drill holes for exploration in the Hamersley Iron Province of Western Australia. Drill hole logs have allowed positive stratigraphic and structural correlations within complexly folded secondary hematite ore deposits and between individual iron ore deposits separated by distances in excess of seventy-five miles. A Neltronics model KPD logging system and gamma-ray sonde are being used to measure the natural gamma radiation of the enriched Brockman and Marra Mamba banded iron formations. The parent banded iron formations are composed of thick, chemically precipitated iron oxide, chert, iron silicate, and carbonate with thin intro-formational clastic horizons. These clastic horizons give a greater natural gamma radiation than the banded iron horizon, and each clastic horizon has a characteristic radiation profile related to its composition and thickness. Because the natural gamma-radiation profile is unchanged during secondary enrichment of the iron formation, the present stratigraphic position of each drill hole can be established and complex folding can be accurately traced in the sub-surface. Gamma ray logging of percussion drill holes has made feasible a significant reduction in diamond core drilling without loss of accuracy. At the same time, it has provided a means of rapid evaluation of complexly folded iron ore deposits.

Jan 1, 1975

By Donald Towse

Portland cement is a basic building material in every country in the world, and, fortunately, the raw materials required in its manufacture are widely distributed. It is a low-priced bulk commodity (price one cent a pound or less, with a density of 100 pounds per cubic foot.) Table 1. Approximate price per pound of selected mineral products. Copper 48 cents per pound Aluminum 27 Lead and zinc 15 Asbestos 3 to 18 Pumice 6 Sulfur 2 Bauxite (abrasive) 1.8 Barite 1 to 1.6 Cement 1 Primitive regions may get along without any Portland cement, but most countries use some, and it is one of the most widespread building materials, even if used in small quantities. Use of cement begins early in a country's development, and, because of local availability of raw materials, cement manufacture is one of the first heavy industries many countries desire. Use and manufacture of cement usually precedes other industrial materials such as steel and heavy chemicals, and consumption levels off for a long period during development of infrastructure and an economic base. With a mature economy comes a very high consumption. Per capita consumption varies ten times or more between nations (Figure 1).

Jan 1, 1970

By Robert E. Hershey

The phosphate industry is the fourth-ranking mineral industry in Tennessee; it has an annual value of 13,000,000 and a yearly production of almost 2,000,000 tons of phosphate ore. Tennessee, at present, is second in rank of phosphate production in the United States. In accord with the importance of this mineral commodity, the Tennessee Division of Geology, is conducting a continuing study of the industry' and the raw s, materials upon which it is dependent. Of the three type's of phosphate found in Tennessee, the brown phosphate rock of the Bigby faces of the Bigby-Cannon limestone is by far the most extensive in occurrence and is the only type being mined at the present time. Because of the importance of the brown phosphate ores, our Division has mapped , in detail the outcrop pattern of the Bigby facies of the Bigby-Cannon limestone. The geologic mapping was done by Dr C. W. Wilson, Jr. and others under his super-vision and the geology plotted on 7 1/2-minute topographic maps, with scale of 1 to 24,000 or 1 inch equals 2,000 feet. These maps will be available for use in the near future and will be published later-with complete geologic coverage.

Jan 1, 1960