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In the last decade important results have been achieved with the usage of geostatistical methods for the solution of geologic and mining problems, particularly in the estimate process of resources in Cuban lateritic deposits. Their uses imply on the one hand, to master fundamental concepts such as: the semivariogram calculation and adjustment, the kriging estimate and the geostatistical simulation, on the other hand, it is necessary to carry out a suitable processing interpretation in each moment, which depends on the experience of specialists on the subject. In this paper, some comments are presented on the article Geostatistical models of the nickel concentration in the domain 7 of Punta Gorda deposit with regard to the geostatistical simulation. [ABSTRACT FROM AUTHOR]

This paper analyzed the importance of integrating disaster risk reduction and climate change adapting policies into the socio-economic development plans of coastal municipalities in Cuba. To this end, a literature review was carried out to locate the main theoretical and bibliographical sources on Disaster Risk Reduction, Climate Change Adaptation, coastal municipalities and government policies and triangulate them to create a four-phase integration tool. This tool will improve the territorial development plans and make them more effective while promoting an integrated vision of disaster risk reduction and adapting to climate change as a fundamental basis for the sustainability of development in Cuba. [ABSTRACT FROM AUTHOR]

Presence of uranium in carbonated petroleum reservoirs has been linked to areas of good permeability, due to the existence of open fractures through which uranium-rich salt waters have circulated. Moreover, uranium is related to organic matter in reducing environments. This paper aims to shed light on nature of uranium in carbonated reservoirs that appear in Cuban gascontrolled formations. For this purpose, wells containing these reservoirs possessing geophysical well logs with electrical images of well wall, natural radioactivity of samples measured in low bottom chamber and total organic carbon content by interpretation of well logs were selected in the North Cuban Petroleum Gas Province. There is evidence that the presence of uranium cannot be considered a direct index of permeability when it appears associated with open fractures as well as closed. It was also showed its association with organic matter in areas where there is no fracturing; hence, in the resulting model, the presence of uranium cannot be considered as index of fracturing and permeability in Cuban carbonates. Integrating data from conventional geophysical well logs, the FMI well wall-imaging tool alongside laboratory work, forms the key to defining the nature of uranium in carbonates. [ABSTRACT FROM AUTHOR]

Mining is an activity that causes considerable damage to ecosystems. This paper aims to argue the convenience of generalizing the implementation of rehabilitation procedures for open-pit mined areas with a socioenvironmental and economic approach, which is essential to make sustainable development viable. The recommended procedure to be generalized incorporates novel elements in the social, environmental and economic dimensions whose effects transcend the rehabilitation of the affected ecosystem and generate impacts that contribute to sustainability in the broadest sense. [ABSTRACT FROM AUTHOR]

The article aims to clarify how the deep sea tailings depositions have been used worldwide as alternative mining practice. The paper is a checking of case studies where this technology is used. The available information sources were consulted, which included: case reports, scientific papers, theses and reports by proper authorities. It is achieved to expose the fundamental principles of operation and environmental impact of this technology in the marine environment by applying empirical methods and theoretical research, as well as an assessment of main cases in the world. [ABSTRACT FROM AUTHOR]

Kaolinitic clays have broad prospects in cement production and as a source of pozzolanic materials. The present paper focused on the petrographic and mineragraphic analysis of the Dumañuecos kaolinitic clay deposit, in the municipality of Manatí, Las Tunas province. In the petrographic and mineragraphic characterization of the rocks, polarized light and reflected light microscopy were used. Petrographic analysis revealed the presence of quartz, feldspars and tourmalines; as well as the predominance of granoblastic and cataclastic textures. It was established, through mineragraphic analysis, that the main mineralogical association is quartz + hematite + goethite + pyrite and cement and zonal textures predominate. The occurrence of feldspar spherules with a fibrous-radial internal structure and traces of feldspar phenocrysts indicate the possibility that the source rock of the reservoir is lava with a rhyolitic composition. [ABSTRACT FROM AUTHOR]

Cojímar Formation, --Lower Miocene (upper part) to Middle Miocene (lower part)--, is a unit in Western Cuba well known for its extensive development and exposure outcrops. It has been widely used in bioestratigraphic studies. However, paleoecological studies on this unit through foraminifera, both planktonic and benthic species, are considered insufficient. The richness and variety of microfossils, especially foraminifera, has allowed us to address the paleoecological aspect. In this paper, the sedimentary environment is established. Besides the systematic classification of these species was updated and the biozonation re-evaluated from planktonic foraminifera. A detailed sampling, from material taken every 15 meters was fulfilled along with a compilation of all species of foraminifera reported for the studied unit. The micropalaeontological analysis allowed the identification of 40 taxa of planktonic foraminifera grouped into 12 genera, being the most representative Globigerina, Globigerinoides, Orbulina, and Globorotalia. Moreover, 226 taxa of benthic foraminifera belonging to 102 genera were determined. These included: Lituolida, Loftusiida, Textulariida, Lagenida, Rotaliida and Miliolida suborders. The main genres represented were Cibicides, Cibicidoides, Cibicobis, Uvigerina, Angulogerina, Anomalinoides, Planulina, Bolivina, Amphistegina, Lenticulina, Nodosaria, and Textularia. Cojímar Formation corresponds to a deep platform, which was determined from the benthic microforaminifera (Uvigerina, Lenticulina, Marginulina) analyzed. Thanatocenoses developed in outer neritic to upper bathyal depths between 100 m - 500m. New reports of both planktonic foraminifera species for that unit as small benthic, such as Anomalinoides flintii, A. trinitatensis, Planulina valued cf. P. mantaensis, Catapsydrax cf. C. dissimilis, Globigerinoides cf. G. obliquus, Globigerinoides primordius, and Hastigerina praesiphonifera were evaluated. As a contribution Gyroidinoides cibaoensis taxon is here first reported to Cuba. [ABSTRACT FROM AUTHOR]

Modeling safety scenarios for dams strengthens effectiveness of disaster risk management plans in this kind of work by reducing risk of failures that can cause considerable damage. The aim of the present paper was a proposal of a modeling methodology for safety scenarios in tailing dams from the Cuban nickel industry, to determine indicators and failure mechanisms, in order to achieve early detection risks and their reduction, as well as to minimize the negative impacts on the economy, the population, and the environment through a risk and disaster management plan. [ABSTRACT FROM AUTHOR]

The article aims to clarify how the deep sea tailings depositions have been used worldwide as alternative mining practice. The paper is a checking of case studies where this technology is used. The available information sources were consulted, which included: case reports, scientific papers, theses and reports by proper authorities. It is achieved to expose the fundamental principles of operation and environmental impact of this technology in the marine environment by applying empirical methods and theoretical research, as well as an assessment of main cases in the world.

This paper presents a multivariate UPD estimator, family member [A,U,T] with parameters p and s, which allows to calculate simultaneously parameters of Weibull K and C at a point Pe from the measured values of these variables in several sampling points. During the 3D estimation, the spatial relationship between the data and the associated values of elevation and roughness of the terrain is taken into account; with the estimated results, a model of wind energy resources is developed, given by a 3D mesh where to each node is associated the values of K and C. Finally, a method of combinatory optimization is described to find the values of p and s such that the mesh model is feasible and optimal for the given data. [ABSTRACT FROM AUTHOR]

The southeastern region of Cuba is the most seismically dangerous area of the country because of its close location to the border of the Caribbean plate with the North American plate. This paper presents two possible scenarios of strong earthquakes, located about 30 km south of the city of Santiago de Cuba, in terms of peak ground acceleration (PGA) and spectral acceleration (PSA). Acceleration values were calculated for most of the municipalities in the eastern region and for several points in the city of Santiago de Cuba. Two earthquakes of magnitudes 7.0 and 7.3 were modeled, with epicenter in the Oriente fault zone. Necessary parameters were investigated in the calculations such as the stress drop and the attenuation function of the seismic waves. The results indicate significant rock accelerations in the municipalities of Santiago de Cuba and Guamá with values exceeding 180 cm/s2. A shaking map is also obtained for the city of Santiago de Cuba considering the spectral amplification of the soil. The maximum values of spectral acceleration for periods of 0.3 s reach 480 cm/s2.

A controversial and a highly debated issue has been estimated the hydrogeological properties of aquifers at the system scale from the geoelectrical parameters that characterize them due to the lack of a theory that supports the existence of functional relationship between geoelectrical parameters and hydrogeological properties. Equations that support a theory that back up the existence of such relationships are developed in this paper. [ABSTRACT FROM AUTHOR]

To obtain the necessary quality in the lateritic ore that is processed at Comandante Ernesto Che Guevara nickel plant, it was designed an integrated system of mining exploitation. This system conceives a technology for the natural drying of the mineral which has important advantages, but it has restrictions that limit its efficient implementation. In this paper, we propose the modifications that make possible to mitigate the limitations of technology, from the systematization of previous results obtained in simulation, modeling, and optimization of natural drying. The proposed innovations, integrally implemented, will improve the planning, execution and control of the process and, therefore, improving the natural drying technology of the laterites. [ABSTRACT FROM AUTHOR]

The welding of steel of low carbon content is a common practice in the nickel industry, where components with steels of these characteristics are manufactured. The objective of the paper was to establish the microstructural behavior of the AISI 1025 steel when it was welded with two types of electrodes (E 6010 and E 7018), the first one deposited as a mattress, and the second one to guarantee mechanical resistance; they were made in a 240 x 240 x 10 mm plate with simple bevel preparation. The microstructures obtained with the electrode E 6010 are of the ferrite type Widmanstátten, columnar ferrite and intergranular pearlite, with a hardness of 345 HV, while with the electrode E 7018 the microstructures are ferrite Widmanstátten, austenite and martensite, with hardness of 332 HV. The decrease in hardness in the latter case is associated with the thermal treatment of multipass annealing. [ABSTRACT FROM AUTHOR]

The objective of this paper is to elaborate a geological-geotechnical model in three dimensions for the Cenozoic section which is the shallowest of Pinar del Rio City. It is intended that the model obtained is used in future as an interpretative basis for geotechnical phenomena arising in the urban environment. The procedure fallowed can be easily applied to other worldwide studies, mainly in the areas that exist a big volume of geotechnical information. The procedure fallowed can be easily reproduced in other study cases worldwide, specifically counting on a wide volume of geotechnical information. Six Engineering Geological Types (EGT) are identified in the model, namely, Artificial fill, Vegetation layer, Marine alluvial coarse grained soil, Marine alluvial fine grained soil, Eluvial soil and Bed rock. The 3D geological-geotechnical model illustrates the spatial arrangement of the EGT above, and can contribute significantly at decision making in urban planning. [ABSTRACT FROM AUTHOR]

Crushing mathematical modeling using particles population balance method is a fundamental tool for process analysis, optimization and design. This paper deals with the evaluation of the fracture events and process in cone and rolls crushers. For that proposes, is taken as reference Whiten (1972) structural model modifying fragmentation distribution function. This function was replaced by Austin and Luckie (1972) expression. For model development, was created an algorithm using Matlab 13a like determining resource of fractures parameters. Model estimated error for evaluated crushers established the viability of its use for modelling and simulation, particularly for rolls crushers that even before were simulated by simple fragmentation models. Classification and fragmentation distribution functions obtained, describe the events and process fracture essentials that take place in both crushers. [ABSTRACT FROM AUTHOR]

Cutting tool condition monitoring system in the industry is mainly used to detect tool wear, breakage and chatter on the tool. In this paper, tool wear with two inclination surfaces angles was investigated in end milling inclined surface using cutting force signals. This study is focused in the time domain radial force amplitude analysis and Root Mean Square (RMS) values for tool wear monitoring in milling process. The RMS value of the radial cutting force is increased with the flank wear and inclination angle increases. The analysis of the RMS values of the radial cutting force can be effectively used for the tool wear progression monitoring during milling operations. It was confirmed that in end milling inclined surface the predominant mechanism of damage is adhesive-abrasive. [ABSTRACT FROM AUTHOR]

This paper summarizes a method to determine the optimum spacing of grade-control drillholes drilled with reverse-circulation. The optimum drillhole spacing was defined as that one whose cost equals the cost of misclassifying ore and waste in selection mining units (SMU). The cost of misclassification of a given drillhole spacing is equal to the cost of processing waste misclassified as ore (Type I error) plus the value of the ore misclassified as waste (Type II error). Type I and Type II errors were deduced by comparing true and estimated grades at SMUs, in relation to a cuttoff grade value and assuming free ore selection. True grades at SMUs and grades at drillhole samples were generated with conditional simulations. A set of estimated grades at SMU, one per each drillhole spacing, were generated with ordinary kriging. This method was used to determine the optimum drillhole spacing in a gold deposit. The results showed that the cost of misclassification is sensitive to extreme block values and tend to be overrepresented. Capping SMU's lost values and implementing diggability constraints was recommended to improve calculations of total misclassification costs. [ABSTRACT FROM AUTHOR]

It is paper has as objective to characterize microstructures the aluminium alloys that are used in the production of cases for slings and obtained by foundry processes. After having lathed and the resistance among the two elements (case-sling) they were pressed with the employment of prints. The magnetic noise Barkhausen allowed to determining the effect of the compression on the cable according to the alloy type. The obtained microstructure is characterized by the size of the grain and their morphology by an orientation of the phase alpha in the alloy Al-Si-Mg, structures dendrites with silicon very fine eutectic in the alloy Al-Si-Cu and it structures polyhydric or acicular for the alloy Al-Si-Mg, this behaviour and a hardness of 224.8 HV, allow to settle down that the alloy of Al-Mg presents better properties to be subjected to compression process. [ABSTRACT FROM AUTHOR]

Kaolinitic clays have broad prospects in cement production and as a source of pozzolanic materials. The present paper focused on the petrographic and mineragraphic analysis of the Dumañuecos kaolinitic clay deposit, in the municipality of Manatí, Las Tunas province. In the petrographic and mineragraphic characterization of the rocks, polarized light and reflected light microscopy were used. Petrographic analysis revealed the presence of quartz, feldspars and tourmalines; as well as the predominance of granoblastic and cataclastic textures. It was established, through mineragraphic analysis, that the main mineralogical association is quartz + hematite + goethite + pyrite and cement and zonal textures predominate. The occurrence of feldspar spherules with a fibrous-radial internal structure and traces of feldspar phenocrysts indicate the possibility that the source rock of the reservoir is lava with a rhyolitic composition.

Cojímar Formation, —Lower Miocene (upper part) to Middle Miocene (lower part)—, is a unit in Western Cuba well known for its extensive development and exposure outcrops. It has been widely used in bioestratigraphic studies. However, paleoecological studies on this unit through foraminifera, both planktonic and benthic species, are considered insufficient. The richness and variety of microfossils, especially foraminifera, has allowed us to address the paleoecological aspect. In this paper, the sedimentary environment is established. Besides the systematic classification of these species was updated and the biozonation re-evaluated from planktonic foraminifera. A detailed sampling, from material taken every 15 meters was fulfilled along with a compilation of all species of foraminifera reported for the studied unit. The micropalaeontological analysis allowed the identification of 40 taxa of planktonic foraminifera grouped into 12 genera, being the most representative Globigerina, Globigerinoides, Orbulina, and Globorotalia. Moreover, 226 taxa of benthic foraminifera belonging to 102 genera were determined. These included: Lituolida, Loftusiida, Textulariida, Lagenida, Rotaliida and Miliolida suborders. The main genres represented were Cibicides, Cibicidoides, Cibicobis, Uvigerina, Angulogerina, Anomalinoides, Planulina, Bolivina, Amphistegina, Lenticulina, Nodosaria, and Textularia. Cojímar Formation corresponds to a deep platform, which was determined from the benthic microforaminifera (Uvigerina, Lenticulina, Marginulina) analyzed. Thanatocenoses developed in outer neritic to upper bathyal depths between 100 m - 500m. New reports of both planktonic foraminifera species for that unit as small benthic, such as Anomalinoides flintii, A. trinitatensis, Planulina valued cf. P. mantaensis, Catapsydrax cf. C. dissimilis, Globigerinoides cf. G. obliquus, Globigerinoides primordius, and Hastigerina praesiphonifera were evaluated. As a contribution Gyroidinoides cibaoensis taxon is here first reported to Cuba.

Modeling safety scenarios for dams strengthens effectiveness of disaster risk management plans in this kind of work by reducing risk of failures that can cause considerable damage. The aim of the present paper was a proposal of a modeling methodology for safety scenarios in tailing dams from the Cuban nickel industry, to determine indicators and failure mechanisms, in order to achieve early detection risks and their reduction, as well as to minimize the negative impacts on the economy, the population, and the environment through a risk and disaster management plan.

The objective of the present paper is to model the behavior of the compressive and thermal surface stresses originated in the wheel of the rotary dryer with the aim of carrying out fatigue and superficial wear tests on the wheels. Firstly, a theoretical model to estimate the surface stresses that originate in the wheel was established. An equivalent geometrical model of the wheel and the contact zone was discretized using ANSYS v.12.1. Lastly, simulations were carried out using the finite element method in order to determine the behavior of the contact stresses. The results showed that the maximum stress acts along the middle of the contact strip and its magnitude increases proportionally with the force on the wheel and its temperature. The highest value of maximum contact stress (415,14 MPa) was observed when the force acting on the wheel was 1 254 467 N and its temperature 100 °C, whereas the smallest value (87,662 MPa) was obtained for 1 153 915 N and 40 °C [ABSTRACT FROM AUTHOR]

This paper deals with the characterization of boride layers formed on the 316 stainless steel AISI type. A superficial treatment was applied through the method of boronizing with solid powder. The characterization of the microstructure was achieved by observing the boride layer and measuring thicknesses using optical microscopy, scanning, EDX and XRD techniques and calculating the superficial micro-hardness based on process parameters. With the results it was possible to evaluate the influence of technological variables on the microstructure of the treated area as well as on the superficial properties in terms of micro-hardness. The analysis of the test results indicates an improvement in the mechanical properties of the superficially modified material. [ABSTRACT FROM AUTHOR]

In this paper, we report several examples of Simpson's paradox in resource evaluation of Cuban lateritic deposits and discuss effects and boundary conditions of the Simpson's reversal. [ABSTRACT FROM AUTHOR]

This paper presents a wavelet-based two-stage progressive compression scheme to compress digital elevation models. This two-stage approach uses the best of two worlds: it uses a high performance and low complexity wavelet-based coding techniques for lossy compression as first stage; during the second stage the reconstructed model is subtracted from the original digital elevation model in order to obtain residuals which later are uniformly quantized and encode without loss to ensure the maximun height error in each point. [ABSTRACT FROM AUTHOR]

This paper summarizes more than three decades of investigation in relation to existing quaternary marine deposits in Cuba. These studies have revealed the existence of some quaternary lithostratigraphic units which are exclusive of the marine environment (Alegrías, Cayo Romano and Cayo Guillermo) and important to improve the Quaternary stratigraphy of Cuba. Some lithostratigraphic units of marine origin exposed in firm ground are missing as their deposits should have been removed as a result of marine transgressions and regressions. In nearly all the 5000 cays of the marine platform, there are unnominated Holocene deposits of marine and paludal environments. The marine platform bottom is partially covered by unnominated Holocene deposits of different granularity and composition, mainly overlaying the Jaimanitas formation. Sedimentation is calcareous in the morphogenetic external zone of the marine platform, with scarce accumulation of sand and vigorous coral growth. The morphogenetic internal zone is dominated by calcareous and calcareous-terrigenous muds and clay. The sectors with no marine platforms are dominated by an outcrop of Jaimanitas formation and Holocene bioclastic breccias. Only at the mouth of the rivers and in the bay there is accumulation of marine and terrigenous sediments with varying grain size. In general, the deposits are characterized by their small thickness and a granulometry and composition complex distribution; which is related to its origin, low input of sediments and the variation in hydrodynamic activity. [ABSTRACT FROM AUTHOR]

This paper presents an overview of the studies in non-nickeliferous weathering crusts initiated more than six decades ago in Eastern Cuba. This overview is based on a detailed literature review and a descriptive-critical discussion on these studies with the main objective of highlighting their achievements and failures. These investigations were motivated by the existence of large mineral deposits associated with different types of weathering crusts in this region and were mainly focused on finding bauxites. However, prospects could not be delineated because the alumina contents in these geological objects were below those required to classify them as bauxites. This limited the evaluation of the possibilities of assimilating these crusts in such industries as the ceramic, construction and refractory, among others, which can contribute significantly to the sustainable local development. Generally, in all these investigations there is an absence of solid mineralogical and geochemical criteria for the characterization and classification of different aluminium-rich weathering crusts. The SiO2-Al2O3-Fe2O3 contents in the region show that most of the weathering crusts as ferrosialitic. There are possibilities of finding sialitic, ferrallitic and allitic types in Cayo Guam, Centeno, Quesigua, Puriales de Caujeri, Quemado del Negro and Cantarrana. In overview, the level of study of the non-nickeliferous weathering crusts widely developed on gabbros, volcanic, metamorphic and sedimentary rocks in Eastern Cuba is relatively low. Further investigations including detailed profile sampling, chemical and mineralogical analyses in Téneme, Centeno, Cayo Guam, Quemado del Negro and Cantarrana are proposed which, in our opinion, are perspectives for allitic deposits. [ABSTRACT FROM AUTHOR]

The difference in the solubility of amylxanthate copper complexes is the main factor of the flotation process for the recovery of dissolved copper ions, aspects in which it hasn't been researched enough. For this reason, it is presented the results of a research in this paper about the behavior of copper complexes as a function of aqueous average pH, evaluating the results from the specific contribution of both: the recovery and the kinetic of the flotation process, which is developed in a laboratory column flotation with potassium amylxanthate as a collector. The main operational variables of the column: liquid and gas superficial rate were constant as well as the initial foaming concentration. The transformation effects that take place in the system amylxanthate-copper-water are evaluated in the pH range from 4 to 13. The result shows an enhancement or increasing in the recovery of copper ions with the increment in the pH value to 11. It demonstrates the strong dependence between the copper recovery with the chemical characteristic of the system, an increment in the concentration of crystalline copper(I) amylxanthate has an increment in the floated copper, associated with this, it shows an increment in the retained gas fraction and in the bubble surface flow, which has direct effect in the kinetic of the flotation process. [ABSTRACT FROM AUTHOR]

In this paper we report a study about the behaviour of the copper amylxanthate complex by means of UV-Visible spectrophotometric technique in the pH range of 2-13 as well as a kinetic study of its formation showing the type of this process. A higher concentration of cupric amylxanthate was found in the range of pH 7 to 10. The Formation of carbon disulphide, in the pH values lower than 7 and higher than 10, shows decompositions of the amylxanthate ion diminishing the complex concentration. Kinetic study of the copper amylxanthate formation in the temperature range of 298-333 K shows that this process is controlled by a chemical reaction. It was also obtained the mathematical model for the kinetic process during the formation of cupric amylxanthate. Models reflect the behaviour of the studied parameters and their statistical significance. [ABSTRACT FROM AUTHOR]

The existence of the zeolite mineral, thomsonite, is reported for the first time in this paper. Thomsonite was found with other zeolites in veinlets that cut brown palagonite tuffs interbedded with green tuffs of Sabaneta Formation (Paleocen-Middle Eocen). The brown tuffs contain analcime and phillipsite and they appear mainly in Farallones locality at about 30 km to the Southwest part of Moa city. These tuffs may constitute a more basic composition member than the zeolitic green tuffs rich in clinoptilolite. The presence of high silica thomsonite of a moderate structural disorder was established, using X rays fluorescence analysis and X rays diffractions, a polarization microscopy and electron microprobe methods. Besides thomsonite, it was found analcime in the veinlets, possibly as a bedrock relic, and natrolite. [ABSTRACT FROM AUTHOR]

The present paper gives recommendations for developing researches oriented to improve prediction of solids concentration in sludge obtained by gravitational sedimentation. In thickener plant of PSA- Moa Nickel S.A. Company this prediction is studied by means of the historical, logical and passive experimentation methods. It is concluded that in order to solve the problem concerning the prediction of the solids concentration in sludge obtained by gravitational sedimentation, it is advisable to focus the research to the theoretical and empiric study of statistical correlation between this variable and the solids concentration obtained by others mechanical separation methods. [ABSTRACT FROM AUTHOR]

The main purpose of the present paper was to determine the multi-variable models to predict the Efficiency of Nickel reduction with greater effectiveness, when varying the chemical-mineralogical composition of lateritic ores in the Herreshoff furnaces. The research was made in a Loza (8 furnaces) of Punta Gorda Plant for working periods of 8 hours during three months. The data bases and their statistical processing were made in EXCEL. As a result, several multi-variable models were obtained , with effectiveness of prognosis superior than 95 %; the high effectiveness to predict the Efficiency of Nickel reduction was demonstrated when organizing the procedure of filtering Data Base by intervals of Limonite: Serpentine ratio (R5); it was confirmed the validity of the procedure of filtering Data Base to adjust the multi-variable models in the particular case of reduction roasting of lateritic ores, which can be employed to create an integrated software for its use in real time with the information in the INTRANET of Plant; it was explained the regularity in the signs and values behaviour of regression and correlation coefficients when comparing the best models of chemical and mineralogical Data Bases, with emphasis on the contradictions of the Ni variable, as well as the variables of Fe, Al and its minerals. [ABSTRACT FROM AUTHOR]

This paper has as main objective to establish a classification of the different types of movements of masses in slopes developed in the territory of Moa. The typology classification is based on the documentation of the movements found in the area, as well as characterization of all the geometric, structural elements and compositional of the material in which it has been developed; besides keeping in mind the classifications more accepted at international level. As a results a proposal is made of classification and description of the movements of masses containing the mechanisms of the slips in three main groups: mechanisms related with fall free of the rock, mechanisms of slips through a defined failure surface and mechanism of movements of masses in a disorganized way. [ABSTRACT FROM AUTHOR]

In this paper are shown the results of utilisation of the Differential Thermal Analysis technique (ATD), in the non- isothermal kinetic investigation of thermal decomposition of industrial basic nickel carbonate purified (free of sulphates) in 513- 633 K interval of temperatures, that excludes the water of hydration eliminated at lowest temperatures. Attention is dedicated to the possibility to use the Kissinger generalisated equation and the application of classical Kissinger method for the determination of kinetic parameters and the limitations of both methods. Also it is determinate the kinetic model for this step of the transformation and are compared the results with others reported previously by the authors. [ABSTRACT FROM AUTHOR]

A wide and detailed review of specialized papers about methods and diagnose index used to soil erosion assessment was done. It was evident the variety of existent methods that allow researchers to select between all of them, those that better satisfy their aims and data availability. Methods based on erosion landform mapping, evaluation and thematic mapping of factors that influence on erosion, field observations, radioactive isotopes, and modeling are described, being remarkable the importance of Geographic Information Systems (GISs) for developing some of them. The exposed methods are classified in qualitative and quantitative taking into consideration the result type they offer. The methods and diagnose index used to soil erosion assessment in Cuba during the last decades was reviewed. [ABSTRACT FROM AUTHOR]

Continuos regimes productions, as nickel production, require the stable operation of electric power systems (eps) against faults, so it is necessary, in order to avoid the prolongation of damage in all the eps, the installation of the protective system that can operate as fast as possible disconnecting the area of the eps faulted. the wrong operation of the protective systems may increment the cost of the industry production and in order to achieve to correct function of them, adequate tools as digitals simulators, are needed. this paper deals with modeling and simulation of protective relays used in the power transformers of two nickel industry. using a virtual library it is analyzed the performance of the protective system install in the industries, detecting deficiency and offering adequated solutions to avoid the increment of maintenance cost, sudden disconnection and wrong operation. using the protective virtual library created in matlab/simulink it is possible to predict wrong operations of the protective systems and offer solutions. [ABSTRACT FROM AUTHOR]

Very often the complexity and variability of a mineral deposit makes difficult to define homogeneous geologic domains that can be used to apply geological control to the estimation of the most important parameters. The fact, that it is not possible to create a geologic model with very well defined units, leads to work with a complex population and considerably downgrades the estimation quality. The cement raw material deposit Pastelillo is a typical case study where it is difficult to reproduce the geometry of the different technological types using the traditional method of geologic correlation. The different lithologies forming the deposits are mixed up as much in the plane as for the vertical direction. These frequent facial changes cause a great lithological and technological variability in the deposit. Considering this fact, it is proposed to use an interpolation method that allows estimating in the presence of complex populations. This paper focuses on the solution to the problem of establishing a technological and resources model of Pastelillo deposit, which involves the use of nonlinear geostatistical estimation technique: the indicator kriging. [ABSTRACT FROM AUTHOR]

The investigation was made in a Loza (8 furnaces) of Punta Gorda Plant for turns of 8 hours during three months The purpose of the paper was to determine the multi-variable models to predict the Efficiency of Nickel reduction with greater effectiveness, when varying the chemistry-mineralogical composition of lateritic ore in the Herreshoff furnace, which constitutes the base for the advanced control of the technological circuit: Mine-Ore Preparation Plant- Reduction furnaces Plant, with the purpose of elevating the productivity, reducing energy consumption and diminishing the production costs. The data bases and their statistical processing were made in EXCEL. As a result, several multi-variable models were obtained , with effectiveness of prognosis superior than 91 %; the efficacy of COMPRAC Software was validated to obtain models based on the mineralogical composition; the utility of the diagnosis method was demonstrated to detect the causes of subjective errors and to select the reliable information in the evaluated technological circuit; An efficient research methodology for the empirical modeling on scale of Demonstrative Production Unit was validated , based in the securing of the technical-operative Similarity of great Plants with continuous regime of operating. [ABSTRACT FROM AUTHOR]

In this paper is developed a methodology to carry out an energetic diagnostic in a given area of a production process. The methodology is particularly applied to the milling section in an ore improvement plant and it allows to reveals the main factors influencing in the unstable behavior of the specific energy consumption in that section. Regulation of feed to the ball mill, states to be the main factor to be controlled in order to reduce the specific energy consumption in 16 % respect the actual media. It is shown the feasibility to get this reduction, so that can be achieved an important profit when the section moves to a more rational use of electric energy. [ABSTRACT FROM AUTHOR]

The precipitation of Ni and Co mixes sulphides is one of the stages of the ammoniacal technological process in the cuban nickel industry, but the oxidation of sulphides disturbs its storage and transportation. This paper exposes results from chemical characterization by X-ray diffraction and mineragraphic analysis of mixed sulphides as well as from the kinetic investigation of the thermal oxidation of samples in isothermal and no isothermal regime. It's determined de most probable model and kinetic parameters of the physical-chemical transformations that occurs in oxidation process. It's concluded that oxidation of mixed sulphide concentrate follows 4 stages: lost of water and ammonio, degradation of superior sulphides, formation of sulphates and degradation of sulphates into oxides. Degradation of sulphides into oxides degradation of sulphides to oxides Nickel and cobalt sulphides obtained through leaching technology carbonates ammoniacal of laterític ferrous nickelitic ore is characterized and is studied in the kinetics of oxidation concentrated in nickel and cobalt sulphides applying the isothermic and not isothermic methods, being determined the most probable pattern and the kinetic parameters of the physical chemical transformations that take place in the process of oxidation. [ABSTRACT FROM AUTHOR]

The paper represents a hydrogeologic regionalization of Pinar del Río province in GIS platform. The principles of elaboration of this map propose the division of the territory starting from the automatic integration of a group of such natural variables as: physical-geographical characteristics, hydrology, geomorphology, hydrogeology and structure particularities. It is recognized the regional regularities and the common features of each hydrogeologic structure, such as: the sources of the underground waters, the recharge conditions, circulation and discharges of the horizons and aquifer complexes, hydrochemical and hydrodynamic zoning. [ABSTRACT FROM AUTHOR]

In this paper a quantitative physical characterization of the chromite concentrated with refractory characteristic belonging to the deposit Merceditas is presented, using for it technicals of infrared and Mössbauer spectroscopies, X-ray difractometry, chemical and grain size analysis. It settles down that the concentrate is constituted by the phases mineralogical well-known as chromopicotite, antigorite and chlorite, being determined its respective cristalo-chemical formula. By means of the techniques of thermal analysis (DTA, TG and DTG) the thermal behavior of a mixture of chromite concentrated and aluminum is studied with the purpose to valuing the possibilities of the products of the reduction like component of saturating mixtures for the thermodifusives surfaces of chromium and silicon in steels. [ABSTRACT FROM AUTHOR]

The potential field inverse problems are difficult to solve by means of automatic methods, one major reason for this is the inability of conventional procedures to locate the globally optimal set of parameters. This paper establish clearly the nature of the multiple optima problem for the research to inversion of potential field data in the six parameters model and investigates the consistency with three global optimization methods. The Multistart Simplex (MSX) method, a Genetic algorithm combined with Simplex (GSX) and the Shuffled Complex Evolution (SCE) method. All of them are able to find the optimal parameters set during the inversion of potential field data for a six-parameter model. In 100 independent trials of each algorithm the SCE procedure appears to be about 3 times more efficient than MSX procedure and twice time more efficient than GSX. The GSX procedure appears to be about 2 times more efficient than MSX. [ABSTRACT FROM AUTHOR]

In the smelting-workshop of the Mechanical Company of Nickel, Moa city, Holguín province, the creation and control of norms of materials consumption in the production of pieces is made of manual form, being a process slow and, sometimes, unreliable. This paper shows software that systematizes economic-technical information of the smelting that is very useful in the decision making from a scientific and technician analysis. The design and development of software are based on the use of the methodologies of analysis and structured design of computer science systems and the object-oriented programming by means of the tools of programming of Borland Delphi version 5.0. It can be used in smelting-workshops dedicated to produce and to repair pieces for the mechanical industry in Cuba. [ABSTRACT FROM AUTHOR]

The exploitation of sand and cruhed stone deposit, establish special problem for the characteristic of the natural environment where it is done. The prejudice for protecting the environment, joined to the legislation does that the mining activity should be done with a rational project that observe previosly the recovering of the affected ground according with the existing ecosystems. This paper presents an evaluation of the environmental impact that carries out the exploitation of fluvial deposit with sand and crushed stone, located into the limits of Alejandro de Humboldt park, both and the prevent measurement that will have to adopt themselves for minimizing the impact over the environment in order to resemble the exploitation and the protection of natural environment. [ABSTRACT FROM AUTHOR]

The synthesis of the Catalogue of Perceptible Earthquakes from 1528 to 1990, which have been obtained and elaborated to be used at the same time as a Data Base in a PC, is presented. Although usually, the periods of time which are used in seismic analysis are limited due to the lack of instrumental information, this Catalogue contain the enough amount of information to allow the extension of that periods of time. As a complement of the Catalogue, examples from the Atlas of Isoseismal Maps of Perceptible Earthquakes which epicenter located in Cuba, was also finished. The last one is fundamental for the characterization of Seismic Attenuation in Cuba in terms of intensity, for Seismic Hazard assessment. The temporal-spatial analysis of the perceptible earthquakes permit us to evaluate the Seismogenic Zones from the Seismotectonic point of view. Furthermore a theoretic-experimental analysis of the Attenuation's Law of Seismic Intensity from Greater Antilles, and the main parameters associated to Seismogenic Zones of Cuba, is showed. These ones were obtained from Isoseismal Maps of perceptible and large earthquakes. The results obtained from the probabilistic and deterministic Seismic Hazard Assessment, for different regions all over the country, have been unified in this paper. From the Seismic Hazard Map resulting, the Seismic Zonation Map with Engineering Purposes was also obtained; the last one was proposed for the New Seismic Cuban Design Code. As a contribution to the characterization of Cuban Seismicity an spatial -- temporary -- energetic analysis of the perceptible aftershocks was made, including their relation with our Seismogenic Zones, obtaining an empirical relationship between the Length of Rupture and the Magnitude values, estimated by Macroseismic Data. [ABSTRACT FROM AUTHOR]

Mineral deposit descriptive models are valuable geological information network usefull to explore and assessment the territories with these atributes in their geologic pattern and makes them perspectives for the discovery of new mineral resources. In this paper a generalized approach is given about weathering as main process in the formation of laterites as well as three proposal of Fe-Ni-Co laterite descriptive models developed on Mayarí-Baracoa Ophiolitic Belt located in Eastern Cuba. [ABSTRACT FROM AUTHOR]