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On 22.12.2005 the General Assembly of the United Nations Organization unanimously decided to proclaim the year 2008 as International Year of the Planet Earth. UNESCO and the International Union of Geosciences decided to develop the programmes within a Trienium of Geosciences 2007- 2009. Thus, the United Nations acknowledge the special role that geosciences may and should play in establishing a better world, their huge potential being utilized in a more rational manner for the benefit of humanity and its sustainabl...

In the course of years in the engineering practice are formed mathematical procedures which are marked as “engineering calculations”. We will characterize the engineering calculations with the following specific features: • the engineering calculations are pointedly pragmatic; • the engineering calculations are based on working formulas; • the results are approximate; • the engineering calculations are developed by experts and should be applied by experts.

Sungun Porphyry Copper deposit is located 75 kilometers northwest of Ahar and 130 kilometers northwest of Tabriz. In order to model the deposit and estimate its reserve, 31068 input data gained from 152 boreholes were used. Cu grade was selected as the major regional variable on which the present research has focused. All of the available data were changed to 12.5-meter composites so that statistical equalization could be reached. Studies indicated that Cu input data had single - population characteristics. To car...

The long-going petroleum exploitation in the Section Cocu determined the increase of chloride concentrations in groundwater. The aquifer system in this area comprises four aquifers, with different extensions, separated by semipervious units. The third and the fourth aquifer are more extended. The third aquifer is in direct relationship with potential pollution sources, such as oil wells and oil pipelines and it is drained by the River Cotmeana. Several monitoring wells were drilled for the purpose of this study, p...

The Chahargonbad area is located in southern part of the central Iranian volcano–sedimentary belt, in Kerman province. The intrusion of several intrusives bodies such as granodiorite, monzonite, diorite, granite and quartz diorite in the volcanic sedimentary sequence have given rise to an intense and vast alteration and copper mineralization in the southern part of this belt different image processing techniques such as color composites, image filtering, band ratioing and principal component analysis have been a...

Rocks are complex and heterogeneous materials. Their complexity is described depends on their mineralogical constitutions which is characterized based on the features of the rocks such as their fabric and texture. It is considered that the texture is an important parameter to evaluation of the mechanical properties of the rocks. In this study, physical and mechanical properties of 9 different rocks were tested according to standards of International Society of Rock Mechanics (ISRM, 1981). In order to analyze the t...

Methane drainage and utilization can be a profitable activity for gassy underground coal mines, also it protects our environment by decreasing “greenhouse” gases. One of the key parameters for methane drainage is permeability of coal. The flow of gas and water through coal samples was studied to investigate its permeability to methane and water. A relationship was found between the coal permeability to methane, and its permeability to water. As the measurements of permeability should be in-situ representative,...

In this paper, we investigate the the lateral displacement of a Gaussian beam by a conductive thin slab is investigated. A description of the Gaussian beam and a lateral displacement of Gaussian beam at a conductive thin slab is given. We construct a plane wave representation of a Gaussian beam incident upon a homogeneous, lossless, isotropic conductive slab. The waves inside and outside the slab are solved analitically by matching the conductive boundary conditions at the interface. Numerical results including th...

The crack propagation researches carried out on rock and rock mass are important in mining, petroleum and natural gas engineering studies. It is assumed that crack propagation is an important design parameter in underground and open-pit mining applications. It has positive effects in some mining activities such as drilling, blasting, excavating, block caving but also negative effects due to cracks formed around mine roadways, tunnels and in landslides. In this research, the marble and travertine were selected as n...

An exploratory data analysis (EDA) technique is based on the box plot and robust-class selection. Calculation of the threshold of anomalous data is based on the determined classes. In contrast to classic statistical processing ( ), in these methods, normalization isn’t needed. This paper is devoted to presentation of EDA application on stream sediment survey data of 1:50000 Shirinkand sheet. 180 Samples were analyzed for 23 elements and because of high censored values of Cd and P, they are omitted from data proc...

A major producer of zinc on the Balkans is Bulgaria (about 100 000 tons per year). The two zinc plants in Plovdiv and Kardjali deliver a part of the necessary raw materials from Bulgaria and the Balkan countries – Turkey, Romania, Greece, Serbia and Macedonia. In this connection an analysis is made of the delivered sulfide zinc concentrates through statistical processing of data about their chemical content. For the aim of processing them according to the classic hydrometallurgical scheme studies are carried out...

The uniaxial compressive strength (UCS) of rocks is an important parameter used in rock mechanics studies. The standard test procedures in order to determine UCS value has been developed by ISRM and ASTM. According to these standards, the tests should be carried out on core samples but they say that the tests should be also being carried out on cube samples. There are a lot of papers published about the size effect of intact core samples. According to the articles and standards, the length (l) - diameter (d) ratio...

Variability of stream sediment survey data have two principal component including syngenetic component relates to lithogenesis and lithogeochemical variation, and epigenetic component relates to mineralization which its determination is the target in geochemical exploration. In regional stream sediment surveys, effective lithologic units in syngenetic component are located in the upstream of related sample. Various methods are used for neutralization of syngenetic component in stream sediment geochemical surveys s...

This study presents preliminary results of our study on the kaolinisation of Tertiary magmatic units in the Biga Peninsula. Volcanic and intrusive rocks of Tertiary age crop out in the vicinity of the HarmancД±k and \"U\ccpД±nar villages of \cCanakkale country, Lapseki town. Volcanic rocks consist of andesites, basalts and rhyolites, whereas intrusive rocks consist of granitic plutons. The granitic intrusions cut the volcanic rocks. Kaolin deposits appears to have formed within the andesitic rocks. The kaoline dep...

Collection and analysis of well data is important process, allowing a reconstruction of the penetrated rocks. Numerous charts and diagrams illustrate all sorts of geological information. Some of them are demonstrated and generalized by well sections from south-western part of the Central North Bulgaria. Logs together with well core and cuttings are the bases for construction of a general Mesozoic lithostratigraphy column. Besides the major lithotypes the source rocks, reservoirs and seals are also outlined. Select...

The Correspondence Analysis Method (CAM) is actually a Non-structural method that could be used to define the anomaly from the background. To apply this method, representative samples of a large area are necessary but knowing the exact location of each sample is not necessary. Base on this method, the litho-geochemical data would be mathematically process to extract the valuable factors needed to plot a two by two diagram. This method has been applied on available data in Enjerd skarn deposit. Five factors have be...

The system is intended for operatively planning and management of the quality of extracted ore in real time. The system includes following features: Creating and maintenance of data base which contains the numeral samplers of the detonated fields, the needed technical and technological indicators etc. Planning of the extracted activities for period, day, shift and part of a shift by different optimization measures. Distribution of the extraction between the coal-faces. Reverse connection with GPS information relat...

A significant range of the landscaped damaged by brown coal mining is one of the base problems of the region of the North Bohemian Brown Coal Basin. The proper application of fertilizable rocks to sterile and phyto-toxic sits is the condition of the success of reclamation works. Natural clayey sorbents are usually of very good use, but the North Bohemian Basin is quite poor with them. Bentonite deposits are significant exceptions. They are a part of tertiary vulcanodetritic strata of the subsoil of a coal seam. Th...

The paper deals with a potential utilization of a laboratory device of a column flotation machine for the flotation of coal. The flotation tests, which were carried out in the laboratory of the Institute of Environmental Engineering at the Faculty of Mining and Geology of V\vSB-TU Ostrava, made use of samples of black coal slurries from Darkov Mine in the Ostrava-Karvin\'a District. The research was aimed to identify optimal condensation of the flotation pulp as well as the most efficient flotation time. The follo...

Question about identification of the dangerous situations during industrial explosive works’ execution is treated in the report. A test is made for systematization of the aspects that cause some damages and problems when work with explosive materials.

Excess amount of coals produced more than demand has to be deposited in stockyards. During this period, coals lose both their economical values and cause environmental problems. It is often that spontaneous combustion event of coals can take place in the cases of convenient conditions are available. In this work, two industrial sized stockpiles were constituted at coal stockyard of Western Lignite Corporation (WLC) in Tuncbilek, Turkey. The size of the stockpiles formed as triangle prism was about 10 m by 5 m widt...

In the report you can see the question for the common requirements towards technologies during executing explosion duties and work consecutiveness. Right technology choice and following the requirements will provide people safety, without refusal high efficiency of the explosion duties.

Four main mineralized vein Groups within the Sar-Cheshmeh Porphyry system have been identified: I) quartz + molybdenite + anhydrite В± K-feldspar with minor pyrite, chalcopyrite and bornite; II) quartz + chalcopyrite + pyrite В± molybdenite В± Calcite; III) quartz + pyrite + calcite В± chalcopyrite В± anhydrite (gypsum) В± molybdenite; IV) quartz В± calcite В± gypsum В± pyrite В± Dolomite. Early hydrothermal alteration produced a potassic assemblage (orthoclase-biotite) in the central part of the stock, propylitic...

This paper presents the geology, reserve estimation and quality assessment of the Sindhali limestone deposit located in allochthonous succession of the eastern Nepal Lesser Himalaya. Geologically, the limestone deposit lies in the Bhainsedobhan Marble of the Bhimphedi Group where the Bhimphedi Group is divided into three formations: the Raduwa Formation, the Bhainsedobhan Marble and the Kalitar Formation from south to north respectively. The study area is further divided into Northern, Central and Southern tectoni...

In this study, optimum enriching possibilities of Topraktepe chromite ore were investigated by shaking table. Shaking table tests were carried out using -1000+500, -500+300, -300 +212, 212+106, -75+53, -53+38 $\mu$m particle sizes and 1000 g samples. From the experimental results, the obtained optimum results are as follow: -300+212 $\mu$m particle size, 12 mm shaking stroke, 6o table angle, \% 25 solid ratio, 300 rpm shake frequency.

Salt weathering is a process of rock disintegration that takes place in a variety of environments and affects many kinds of rocks. Salt crystallization is one of the most important degradation mechanisms on the effect of rock weathering. Salt weathering is especially effect on the pores rock and affects the rocks, which contains cracks and micro cracks. In this study, the resistance of stones against salt weathering was estimated by ultrasonic measurements and weight loss approximation. Experiments were carried ac...

Norm Statements Actual that settle the questions related to the execution of industrial explosive work are considered in the report. There are shown the main requirements stationary for all who execute some industrial explosive works and actions with explosive materials.

Problem about the directions for improving the healthy and safe work conditions during the execution of explosion duties is put into attention in this article. It is about the assessment for the enabled risks during operation with the explosion duties and the necessity of using some precautions and actions for averting, decreasing, and limiting their existence or inventing a protection towards them.

This paper present a geophysical investigation performed for the Bakhtiary dam site in Iran. As it has been designed with 330 meter high, this dam would be the highest dam in the world. In the context of engineering seismology, seismic tomography may be relevant in problems where seismic refraction is currently used. Both of these techniques aim to detect subsurface velocity. In Bakhtiary dam site we used seismic refraction, tomography and borehole seismic tomography methods. For refraction seismic method Geotomo ...

The method for exploiting the coal layers by using the crazing and submitting the roofs of the mining works from the underground is an alternative applied on large scale into the brown coal mines from the main coal basin Jiu Valley situated into the S-W of Romania. The technology of individual supporting – by using the open circulation hydraulic props together with the linked metallic bars with blocking bolts and wedges, assume some great physical efforts and the factor of working security is not totally assured...

The principal disturbances created by blasting in open pit mines can be listed as ground vibrations, air blast and fly rock. All of them can, under some circumstances, cause damage to structures nearby, and can become the source of permanent conflict with the inhabitants living close to the operation site. Therefore, the prediction of ground vibration components is of great importance for the minimization of the environmental complaints. This paper presents the result of ground vibration measurements induced by be...

The ultramafic rocks around Kizildag have very important economic reserves of chromite and olivine. The ultramafic rocks are mainly composed of dunites and in lesser amount diabases. The dunites are mainly made of forsteritic olivine which is about 90 \% of the rock mass. The chemical composition of the rock is as follows: MgO 52.25 \%, SiO2 37.5 \% and Fe2O3 8.3 \%. These mineralogical and chemical characteristics are met the need of iron-steel and refractory industry. The olivine deposits of Kizildag with 9 bill...

In the condition that drilling and blasting technique is inevitable depending on the rock mass and material characteristics on mining activities, the fragmentation rate and particle size distribution of the muckpile after blasting has important influences on the performance of subsequent mining activities such as loading, hauling, crushing, grinding etc. and the total costs of that mine. Drilling and blasting is an important step in this process chain and it’s results such as fragmentation, muckpile shape and lo...

In this study, the amenability of Akoluk (Ordu -Turkey) ore to the extraction of gold and silver by cyanide leaching was investigated. Mineralogical analysis of the ore has revealed the presence of native gold and a variety of minerals including barite, zinkenite, stibnite, orpiment, realgar, cinnober, pyrite and sphalerite. No silver was detectable under microscope suggesting that it could be present as occluded in minerals such as fahlerz, antimonite and zinkenite. Gold particles as 1-88 $\mu$m in size were obse...

A structural analysis on the used in processes of open cast mining formula is made and some functional dependences are deduced. This shows the relation between optimal speed on temporary rail ways and the productivity of mounding excavator – single – bucket and with many buckets.A structural analysis on the used in processes of open cast mining formula is made and some functional dependences are deduced. This shows the relation between optimal speed on temporary rail ways and the productivity of mounding excav...

The flyrock from blasting operations can harm, damage or expose the workers of a particular worksite or the dwellers of a wider area of extractive activities (quarry, mine, construction site) to damage risks; in some cases even death might be caused, too. There are certain and different ideas and theoretical approaches regarding the evaluation of causes and the implementation of flyrock prevention measures to be taken, as well. This implementation, however, in practice requires a more delicate and rather professio...

Paste backfill is composed of a mixture of mine tailings, process and/or fresh water for the desired solid-water consistency and hydraulic binder to ensure a target mechanical resistance. This paper presents some studies undertaken on the strength development and deformation behaviour of paste backfill mixtures made from a Turkish zinc mine tailings. A series of laboratory experiments was conducted to determine the strength and deformation properties of paste mixtures with binder content ranging from 4 to 7 wt\% a...

The transport represents one of the main sides of the mining technological process, the preponderance of the expenses of this activity reported to the expenses for producing a tone of useful mineral substance extracted from the underground reaching almost 40\%. A good transport system presumes to assure a permanent continuity with passive time cycles having minimum values and functioning in well correlated cascade dimensionally and capacitive speaking. It’s obvious that a transport flow is performing if starting...

Nickeliferrous laterite is a source of ferronickel alloy extracted by a pyro-metallurgical process. Laterite deposits found in Greece are mainly secondary depositions and their nickel content is about 1\%. Beneficiation of the run of mine ore is limited to the +1 mm fraction by magnetic or gravitational processes and its effect is rather unsatisfactory due to the insufficient liberation of the nickel bearing minerals. The mineralogical structure of the ore consists mainly of hematite nodules (pissoids) and quartz ...

In this study, diagnostic leaching and ultrafine grinding as pretreatment step ahead of two-stage cyanidation of KaletaЕџ ore were studied to shed light on the refractory characteristics of ore. The overall gold extraction of 93\% was achieved in two-stage cyanidation of ultrafinely ground ore suggesting the presence of readily recoverable gold (74\%) and slowly reacting gold (19\%) in the ore. Diagnostic leaching approach provided information into the cause of the refractoriness of the ore. The findings of diagno...

In this study, flotation concentration of Trabzon-KayabaЕџД± Massive Sulphide ore was investigated. The effects of particle size, reagent concentration (collector and depressant) and agitation speed on the recovery of copper were studied. The results have shown that the ore responded poorly to concentration by flotation with low efficiency of seperation of copper minerals from sphalerite and pyrite. Changing the flotation conditions i.e. decreasing particle size to >99\% passing 38 $\mu$m or increasing the concent...

The influence of temporary rail ways over transporting ability through the mining railway net in open cast mines is researched. A functional relation between optimal speed of temporary ways and the transporting ability is found.

As it is well known, the process of extracting from the underground the reserves of useful mineral substances by using mechanical methods had been extended mainly regarding the energetic coal a series of countries in the period of 1970 ? 1990, that generated many actions of conception and manufacturing of some specific equipments being remarked mainly Germany, England, Poland, ex - countries of Soviet Union, etc. The main idea consists in choosing and correlating dimensionally, capacitive and functionally some com...

The optimization of the coal winning process using different mechanical and alternative cutting techniques using appropried mathematical models is an up to date reserch methodology. In the paper, two kind of such models are presented, first using deterministic analytical relations evaluated by numerical calculus, and the second using Monte-Carlo simulation of the process using experimentally obtained test data to generate random values of intrinsic rock parameters and logic diagram for the functional connections b...

In this material offers mechanical model that builds on the basic technological characteristics of the system rock – frictional pipe anchor bold (FPA). In the presentation, the anchor is divided on the modeling elements. Their size is determined from the physical model that describes combined anchor-rock system work. Key words: mechanical model, system anchor-rock, stress field

An ongoing geologic and geophysical investigation in the deep-water Black Sea, offshore Bulgaria reveals conditions suitable for hydrocarbon accumulations with giant field size potential. This potential lies within the buried offshore extension of the Paleogene Balkanide fold belt and its adjacent Eocene-Oligocene foreland basin, in water depths of 500-1,700 meters. With the benefit of onshore geologic studies and new offshore seismic acquisition and processing, it is possible to recognize and evaluate the basic e...

In this study, diagnostic leaching and ultrafine grinding as pretreatment step ahead of two-stage cyanidation of KaletaЕџ ore were studied to shed light on the refractory characteristics of ore. The overall gold extraction of 93\% was achieved in two-stage cyanidation of ultrafinely ground ore suggesting the presence of readily recoverable gold (74\%) and slowly reacting gold (19\%) in the ore. Diagnostic leaching approach provided information into the cause of the refractoriness of the ore. The findings of diagno...

The paper makes a general presentation of the firedamp resources of the world and the exploiting methods used before, during and after mining activitites. The evaluation of firedamp quantities from the coal bed in exploitation at active mines in Jiu Valley Outgas systems in exploitation at mining units in Jiu Valley and the monitoring of firedamp emissions from these mines Solutions to recovery the firedamp from closing mines Firedamp marketplace – energetic resource for the future.

Results from students’ education in subject “Explosions in Industry” are noted in the protocol. It is towards sector “Education of Bulgarian Citizens” to the Complex Center for Education and Qualification of MGU “St. Ivan Rilski”. There is a short analysis for study plans, programs, way of taking certificate for work with explosives and there are some offers for improving the education quality.

The Sabzevar complex ophiolite including igneous rocks consist of peridotites (lherzolite, dunite and harzburgite), serpentinite, gabbros and a volcanic sequence composed of basalts, andesites, rhyolites and basanites. Based on petrographic observations and geochemical analyses of incompatible trace and rare earth elements, three different types of extrusive rocks have been classified. a: Initial molten originated N-MORB-like basalts, which formed after a LREE depleted magmas, and are petrogenetically related to t...