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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]

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. [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]

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]

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]

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]

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]

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]

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]