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By S Talu, E Savage, S Howe

Major falls of ground, strainbursts, airblast and mudrush events are the major hazards in block caving environments, resulting in both safety and financial consequences and losses. Rio Tinto mines have developed strategies to reduce the likelihood of these events occurring. However, until recently, there have been no tools available to monitor and manage these hazards in real time.Mira Geoscience and Rio Tinto have collaborated to develop real-time geohazmaps to monitor and manage major cave hazards. These geohazmaps are used by mine planners to integrate multiple hazard parameters that contribute to form a combined hazard rating.The benefits of implementing geohazmaps include safety and cost improvements through the early identification of potential locations for major events. These cost savings are realised in the design phase, where development and critical infrastructure is located in areas of lower hazard rating. Additional improvements can be achieved by taking the hazard level into consideration when planning the production and development schedules and ground support design.CITATION:Talu, S, Savage, E and Howe, S, 2016. Geohazmap implementation in block cave mines, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 817–822 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By A. S. C. Owili-eger

Coal mining is one of the major activities that may affect the natural or existing hydrologic equilibrium of a basin. Consequently, the mining industry is committed to the conservation and protection of the hydrologic balance within and around mining environments. This commitment embodies thorough and careful consideration of the quantitative and qualitative variations and, in general terms, the environmental impacts of mining activity on the natural water systems. A research program was undertaken to study the impacts of full extraction coal mining on the ground water systems at one of the coal basins in the Appalachian region. The primary objective was to provide reliable information for determining the local and possibly the regional effects of longwall mining on well yields, and the hydraulic and hydrogeochemical parameters of the immediate surface and subsurface water resources.

Jan 1, 1985

By Angelus S. C. Owili-Eger

The investigation into the hydrologic and hydrogeochemical influence of longwall coal mining in the Appalachian coal basin was under- taken in response to the need to technically address problems of damaged or impaired well yields, and quality deterioration. Prior to this study, issues regarding reduced aquifer yields and degraded water quality had to be handled in a very qualitative manner. Such an approach would, in the long run, claim a heavy toll on the mining industry. The primary objective of this undertaking, therefore, was to provide sufficient and reliable information base for the determination of the local and possibly the regional effects of longwall mining on well yields, and the hydraulic and hydrogeochemical parameters of the immediate surface and subsurface water systems. Specifically, the program was designed to supply definitive data to answer the following series of questions: 1. Does longwall mining affect the quantity and quality of water in local wells above and adjacent to longwall panels and barrier pillars? 2. If the water quality is affected as soon as mining takes place, does it heal? or if it is not affected immediately, does it change over a longer period of time? 3. How do the aquifer water transmitting characteristics respond to induced physical ad hydrologic variations? 4. What is the extent of the various changes in quantity and quality of the water resources? 5. Should and can standard hydrologic evaluation techniques be used to determine the hydraulic properties of highly fractured zones located within a larger and less permeable aquifer?

Jan 1, 1983

By Buisman C. J N, Koch R. O

Soil and groundwater beneath the Budelco zinc production plant at Budel-Dorplein (The Netherlands) are contaminated with metals and sulphate. To avoid contamination of nearby drinking water aquifers in the very distant future, a geohydrological containment system (GCS) and a microbial treatment plant for extracted contaminated groundwater have been developed. As a first step in the design of the system groundwater data from over 150 wells and geological profiles were used to model geohydrological conditions beneath the site. Several configurations of water-extraction wells were deduced from the model. Data gathered during additional fieldwork were then used to improve the model. Finally results that were calculated for the various configurations were used to select an optimal groundwater containment system. Currently some 5000 m3/day groundwater are extracted from a combination of 12 shallow and deep wells. Heavy metals and sulphate have to be removed from the extracted water before it can be discharged into the river system or used as process water. Several water treatment methods have been studied and pilot-tested at the site. The preferred and selected process is based on the activity of sulphate reducing bacteria (SRB) and combines sulphate removal and heavy metal removal in one single step. The anaerobic bacteria reduce the sulphate to sulphide resulting in the precipitation of metal sulphides. A pilot plant gave promising results and a commercial-scale plant has been designed. The proposed design has been tested in a demonstration plant which included all main process units. Test results for all process units are presented. The collected information was then used to optimise the design of the commercial-scale plant. Special attention was paid to automation and safety items. Construction of the plant was finished in May 1992. Start-up, commissioning and operational experience are reported. The concentrations of metals and sulphate in the effluent of the SRB water treatment plant are well within the limits set by the authorities for discharge to public waters.

Jan 1, 1993

By E. A. Noble

In the Western Coal Region, successful reclamation of surface-mined areas includes the protection of groundwater sources. To accomplish this, a complete understanding of the geohydrology of the affected area is imperative. Successful mine design also calls for careful attention to geohydrology. Because the Western Coal Region is semi-arid land used mainly for farming and grazing, groundwater is a particularly sensitive topic. It is especially sensitive where the lignite scheduled for mining is itself the aquifer supplying the farms and ranches. Such is the case throughout much of the Western Coal Region, particularly where there are no near-surface sand and gravel aquifers that are commonly found in the glaciated portions of the Region. Just as mining can adversely affect groundwater supply, so can groundwater adversely affect mining. Mine flooding and highwall instability are examples of this. But, mine operators must realize that procedures they use to remedy geohydrologically-related mining problems can have a dramatic effect upon ground- water conditions in areas adjacent to the mine. A logical precaution is to require the acquisition of complete baseline data prior to making the first cut. We recommend that the mining plan not only incorporate the reclamation plan, but that they be developed as one plan.

Jan 1, 1976

By M. Portal, L. Goicochea

This study is carried out in the Zenit mining concession, which is located in the city of San Pablo in the department of Cajamarca in Peru. The Project has 33 mineralized structures and according to laboratory analyzes we have the presence of gold and silver. The geostatistical evaluation provides an analysis on the distribution of precious metals in the vein. This information is used to improve the efficiency of metal extraction and to reduce costs. The general objective is to evaluate the polymetallic veins (Au and Ag), for which the classification of resources (measured, indicated, and inferred) has been carried out, taking into account the parameters of minimum distance from the composite, corresponding volume and tonnage calculation. In addition, an inventory of estimated geological resources was carried out with the block grades obtained to generate the tonnage-grade curves.

Feb 1, 2024

By Maurizio Siepi

The realisation of most of the civil engineering works is subordinate to the execution of consolidation works, in order to improve the soil physical-mechanics characteristics. The works classifiable with the term "Soil Improvement" can be realised using several technologies, among which the Deep Mixing Method is distinguished for his remarkable flexibility and productivity characteristics. The Deep Mixing Method is a process whereby a rotary drilling machine mechanically drills a constant diameter hole while cement slurry is injected into the soil at high pressure. The process combines state of the art construction techniques merging mechanical and hydraulic mixing energies at the tool bit. The result is a soil-cement column of engineered strength, consistency and dimension. Whereby the soil cement column formation process is controlled by a computerised device, the result is a speedy installation, thorough mixing, and a high degree of control, repeatability and documentation.

Jan 1, 2002

Carbonate replacement tin deposits in the areas studiedhere are genetically related to biotite granites. Biotite in the granites is distinguished by distinctive compositional features. High MgO content is found in biotite in the Renison Bell granite; high MnO and A1203 contents in the Gejiu granite; and high FeO content in the Xinlu granite. The compositional features of biotite in the granites are reflected in skarn minerals formed around the granites.Granites associated with these tin deposits are characterized by different accessory minerals. Magnetite-bearing granite in the Xinlu deposit is related to the andraditic garnet (andradite 40-45 mole%)-hedenbergite skarn, with tin mineralization occurring in the contact skarn only. The sphene-bearing granite in the Gejiu deposit is related to the grossular garnet (grossular 50-60 mole%, almandine 20-30 mole%) -salite skarn, with tin mineralization occurring in the contact skarn, as well as stratabound replacement orebodies in the distal skarn. The ilmenite-bearing granite in the Dachang deposit and the Renison Bell deposit is related to the grossular-diopside skam, with tin mineralization occurring 500-1500 metres vertically and 1.5-3 km horizontally away from the granite contact.

Jan 1, 1990

By A. E. Moss, J. K. Gustafson

MEASURED in terms of ore tonnage, the New Quebec and Labrador iron ore fields promise to rank with the greatest iron ore districts of the world. Over 400 million tons of high-grade ore for direct shipping have been discovered to date. Much greater amounts of lower-grade beneficiating ores are indicated by outcrops. Many hundreds of square miles of iron formation await testing. By 1954 iron ore will begin to move towards American blast furnaces, and shortly thereafter the annual rate of production is expected to reach 10 . million tons. To bring this vast project into being over $200,000,000 will have been spent for exploration and development, mining equipment, hydro plants, townsites, the building and the equipping of . a 360-mile railroad, and the construction of docks and ore-handling facilities. The most important iron ore deposits are located over 300 miles from tide water, see frontispiece and also Fig. 1. The frontispiece shows principal sources of iron ores and manganiferous iron ores for the U. S. and Canadian steel industry, and the major smelting districts are shaded on the map. No navi- gable rivers lead into the interior. When work was . commenced on this project there were no roads, no railroads, no communication ,system, no inhabitants, and no adequate maps either topographical or geological. The geological field season was limited to approximately 100 days per season. The obstacles facing this enterprise were many and varied. Its success will be due to the integrated team work of people of diverse skills. Explorers, Indian guides, prospectors, geologists, surveyors, mechanical, civil, electrical, and mining engineers,

Jan 1, 1954

The ability to track miners and communicate with them while they work in underground coal mines is important during normal daily operation, and critical in emergency conditions. This was evident during recent incidents at underground coal mines worldwide. Communication with miners and the knowledge of their location is of great importance for rescue efforts and the preservation of life. Numerous technologies have been developed, adapted and deployed to meet tracking requirements of the Mine Improvement and New Emergency Response (MINER) Act of 2006. Evaluating the performance of these systems has proven to be dif?cult for mine operators, system manufacturers and regulatory agencies. The MINER Act requires operators to improve accident preparedness by developing an emergency response plan speci?c to each mine. With the recent implementation of the provisions of the MINER Act of 2006, all underground coal mines in the United States are subject to the mandates of legislation concerning communication and tracking system installation. As of June 2011, 203 new or revised tracking and/or communication systems had been approved by the U.S. Mine Safety and Health Administration (MSHA), with nearly 50 other systems or revisions in the approval process (MSHA, 2011). At that time, the available approved systems for underground coal mine use included these types: ? Leaky feeder communication systems. ? Fixed node-based communications and/or tracking systems. ? Wireless node-based communications and/or tracking systems. ? Medium frequency (MF) communication systems. ? Communication system peripherals. Other types of tracking systems have since been developed and some manufacturers are seeking approval for use in this application. Some of the new products include through-the-earth (TTE) systems and various radio frequency (RF) adaptations. New technologies that are currently being developed and deployed in other industrial applications should also be considered, including acoustical, optical, inertial and hybrid technologies. To date, no uniform method has been employed in the industry to effectively compare and evaluate the performance of installed systems. Neither industry operators nor regulatory agencies can accurately assess the capabilities of installed systems in the continuously changing mine environment. There is a need for a uniform evaluation method that provides the ability to assess how different systems and technologies perform in various mining applications, and whether they can satisfy the regulatory requirements.

The ability to track miners and communicate with them while they work in underground coal mines is important during normal daily operations, and critical in emergency conditions. As was evident during recent incidents at underground coal mines worldwide, communication with miners and the knowledge of their location is of great importance for rescue efforts and the preservation of life. Numerous technologies have been developed, adapted, and deployed to meet tracking requirements of the Mine Improvement and New Emergency Response (MINER) Act. Evaluating the performance of these systems has proven to be difficult for mine operators, system manufacturers, and regulatory agencies. The MINER Act of 2006 requires operators to improve accident preparedness by developing an emergency response plan specific to each mine. With the recent implementation of the provisions of the MINER Act of 2006, all underground coal mines in the United States are subject to the mandates of legislation concerning communication and tracking system installation. As of June 2011, 203 new or revised tracking and/or communication systems had been approved by the Mine Safety and Health Administration (MSHA), with nearly 50 other systems or revisions in the approval process (MSHA, 2011). At that time, the available approved systems for underground coal mine use included these types: ? Leaky Feeder Communication Systems ? Fixed Node-Based Communications and/or Tracking Systems ? Wireless Node-Based Communications and/or Tracking Systems ? Medium Frequency (MF) Communication Systems ? Communication System Peripherals Other types of tracking systems have since been developed and some manufacturers are seeking approval for use in this application. Some of the new products include Through-the-Earth (TTE) systems and various radio frequency (RF) adaptations. New technologies that are currently being developed and deployed in other industrial applications should also be considered, including acoustical, optical, inertial, and hybrid technologies To date, no uniform method has been employed in the industry to effectively compare and evaluate the performance of installed systems. Neither industry operators nor regulatory agencies can accurately assess the capabilities of installed systems in the continuously changing mine environment. There is need for a uniform evaluation method that provides the ability to assess how different systems and technologies perform in various mining applications, and whether they can satisfy the regulatory requirements.

Feb 23, 2014

By Howard J. Brown

The Lucerne Valley limestone mining district is in the San Bernardino Mountains, one of the major ranges in the Transverse Range Province of southern California. Several large limestone mining operations are present along the north range front in Lucerne Valley, and the area is one of the premier limestone mining districts in the country. Resources are contained in Paleozoic carbonate rocks that are part of a thick late Precambrian and Paleozoic sequence that uncomformably overlies crystalline basement. The district has been affected by multiple episodes of metamorphism and deformation, as well as by a complex sequence of late Cenozoic structural events. Detailed studies, however, have demonstrated that these rocks can be divided into formations correlatable with late Precambrian to Permian strata of the Cordilleran miogeocline. The district is the leading producer of white, high-purity calcium-carbonate products in western North America. Pluess-Staufer (California) Inc. mines and processes high-purity white limestone from extensive deposits, and is one of the largest producers of high-quality limestone fillers and extenders in the western United States. Major factors influencing the genesis of economic carbonate deposits in the district include depositional environment, post-depositional processes such as diagenesis, dolomitization and/or silicification, regional and/or contact metamorphism and associated intrusive activity, faulting, folding, uplift and erosion, and preservation from erosion. Regional geologic studies, detailed geologic mapping, intimate knowledge of stratigraphy, and recognition of complex structural relationships have proven to be invaluable tools in the discovery of high quality calcium carbonate deposits in the district.

Jan 1, 1987

By O. H. Rostad

The importance of geology in ore reserve estimation has been stated by several authors. King et, a1 (1982) reported that the geological factor was the key deficiency where serious weaknesses in ore reserve estimation appeared, especially in grade. The foundation for a successful mining operation is an ore reserve estimate that neither overstates nor understates the true situation as to tonnage and grade. Overestimation of reserves can have devastating economic results. Overestimation of tonnage may lead to wasting money on an overbuilt plant or worse yet, if grade is seriously overestimated also, to undertaking an operation that is doomed to economic failure from the outset. Understated ore reserves can result in building a plant that is smaller than optimum which may result in higher unit costs. At worst, understated tonnage of ore reserves can result in a missed opportunity for a profitable operation. Failure of the ore reserve estimator to properly take into account all geologic and allied factors pertaining to the deposit can result in an ore reserve estimate that is overstated either as to tonnage or grade or both. This paper will focus on these factors and will not discuss rules about distances above or below a drift that should be given a classification of proven or probable, etc. Each deposit has its own particular characteristics which often require modification of general rules for defining limits of proven and probable ore blocks that work satisfactorily in another deposit. A number of references are included which discuss some of these problems. Definitions of ore reserve classifications and an illustration are given in the Appendix.

Jan 1, 1985

By D. E. Ranta, Ora H. Rostad

Ore reserve estimation, from the earliest "quick and dirty" estimates made at the first consideration of a possible project down to periodic revisions of detailed estimates made during the life of a mine, should take into account many geologic and allied factors in order to obtain results that will provide proper guidance for necessary economic decisions. Factors include: sample collection and analysis, character of the vein and associated wall- rock, mineralogy, pre and post mine oxidation effects, core loss, sample correlation, internal vein structure, wallrock controls, geologic factors affecting dilution in mining and interrelated mining and milling problems.

Jan 1, 1992

By William Ives

My presentation is from the viewpoint of the industrial mineral geologist, which is a relatively rare breed. Very few geologists become involved with industrial minerals for two reasons, I think: (1) Much of the industry utilizing non-metallic minerals has developed without the use of geologists in the begin¬ning and many of the management people, who generally derive from the processing plant supervision, tend to take raw materials for granted; and (2) non-metallic minerals are a very insignificant part of the curriculum of virtually all colleges granting a geology degree. One learns about the geology of industrial minerals by working with it. This "on-the-job-training" is probably best because it brings the geologist into close quarters with the production people and the production process. And the industrial minerals field has a distinctiveness when compared with the petroleum or metal mining field in that each deposit can yield a material differing in some aspect from that in any other or within the same deposit. The petroleum from a well in a given field will be similar to that from any other well, but a limestone on one side of a hill can differ signifi¬cantly in elemental composition, calcinability, soundness, specific gravity, or some other factor from the same ledge on the other side of the hill. This characteristic of almost certain variability creates problems sooner or later and provides for much of the employment of industrial mineral geologists. My job seen from the viewpoint of management is "Find us some rock we can extract and process at a profit." The industrial non-metallic geologist has much the same problems and approach as a detective. I do not mean the TV variety with the big mouths and the unfailing knack of spotting the wanted criminal immediately in a city of ten million people. Any real detective will tell you it takes leg-work, knowhow, and persistence to make a case. The same is true for the geologist who finds rock which can be quarried at a profit. I am responsible for finding raw materials for a company which manufactures portland cement and

Jan 1, 1977

By William S. Hallager

Banded ironstone and associated fine-grained carbonaceous sediments near Jardine, Montana, are enriched in gold, arsenic, and tungsten. The mineralized sediments lie within a thick sequence of quartz-mica schists cut by a 2.6 b.y, granite. Surface, underground, and drill hole mapping are used to construct structure contour maps of individual ironstone lenses. Each lens is then unfolded by triangulation of minimum surface path distances between drill hole penetration points. Major and minor element abundances in composite ironstone samples are interrelated through R-mode factor analysis. Results indicate five significant element groupings thought to reflect coarse detrital, fine detrital, sulfide-rich chemical, iron-rich chemical, and epiclastic ultramafic sediment. Ultramafic factor scores are highest in a previously undefined rock type rich in cummingtonite, biotite, and chlorite; lacking in quartz; and closely associated with at least one ore horizon. Detrital dilution of ironstone, calculated from chromium and nickel content, drops off significantly as ore-bearing ironstone is approached. This observation may indicate that centers of gold precipitation have protected themselves, either topographically or by rapid deposition, from detrital contamination. Gold mineralization correlates most strongly with the sulfide- rich factor. Gold may have been introduced through hotspring activity as a bisulfide complex.

Jan 1, 2013

By James W. Clark, William C. Dixon, Kevin L. Wiley, Thomas R. Couzens

This paper is a description of certain geologic aspects of the Inspiration mining operation. It is not a geologic description of the Inspiration deposit nor an exposition of all the geologic work. Involved in the development and exploitation of the deposit. A few specific examples of the application of geology and geostatistics to the mining process are given to illustrate the progress that has been made in making the Inspiration Mine more efficient and cost effective, and a statement of the philosophy of geologic applications is offered.

Jan 1, 1985

By James W. Clark

This paper is a description of certain geologic aspects of the Inspiration mining operation. It is not a geologic description of the Inspiration deposit nor an exposition of all the geologic work involved in the development and exploitation of the deposit. A few specific examples of the application of geology and geostatistics to the mining process are given to illustrate the progress that has been made in making the Inspiration Mine more efficient and cost effective, and a statement of the philosophy of geologic applications is offered.

Jan 1, 1984

By R. A. Metz, James W. Clark, William C. Dixon, Kevin L. Wiley, Thomas R. Couzens

This paper is a description of certain geologic aspects of the Inspiration mining operation. It is not a geologic description of the Inspiration deposit nor an exposition of all the geologic work involved in the development and exploitation of the deposit. A few specific examples of the application of geology and geostatistics to the mining process are given to illustrate the progress that has been made in making the Inspiration Mine more efficient and cost effective, and a statement of the philosophy of geologic applications is offered.

Jan 1, 1992

By E U. Petersen, D R. Cooke

Hydrogen and oxygen isotopic constraints on hydrothermal fluid composition from the Pliocene Boyongan and Bayugo porphyry copper-gold deposits (southern Philippines ) reveal mixing of magmatic and sea water reservoirs as the hydrothermal system evolved. Magmatic-equilibrated fluids (d18O: +8.3ë to +9.1ë; dD: -61ë to -51ë) are represented by hypersaline brines implicated in copper-gold transport and deposition. These dominate the fluid inclusion assemblage in early comb-quartz (unidirectional solidification textures), miarolitic quartz, and in K-silicate-stage quartz-K-feldspar ¦ biotite veins. Fluids responsible for post-K-silicate alteration assemblages of pyrite-clay (illite, pyrophyllite and kaolinite), alunite and smectite are represented by low-moderate salinity two-phase inclusions in co-existing quartz. These are interpreted as mixtures of evolved magmatic fluids (d18O dD: -42ë to -20ë) with evolved Pliocene sea water (d18O: + 4.0ë; dD: +4ë). The isotopic evidence for sea water involvement in the hydrothermal system suggests that porphyry emplacement and associated diatreme formation could have occurred in a submarine setting. An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation.

Jan 1, 2008