MINERAL DEPOSITS

Author: DEMOUSTIER AXELLE.
Year: 2001.
University: POLITÉCNICA DE MADRID [www.upm.es].
Place of defense: E.T.S. INGENIEROS DE MINAS.
Place of preparation: E.T.S.I. MINAS Y FACULTÉ POLYTECHINQUE DE MONS.

Summary: In order to investigate the conditions of formation of the veins epitermales low sulfuracion (type adularia-sericita) of Cabo de Gata, in the province of Almeria (Spain Southeast Region Volcanic Neógena) and deposition of the mineralization in Pb-Zn and Au-Ag have been studied stages siliceous through multidisciplinary methodology including several techniques which come from the observation of field filoniano, the study of microscopic defects at (fluid inclusions) and scaled to the network crystalline (luminiscencias crystalline: thermoluminescence and catodoluminiscencia) . The textural study underlines the great diversity of textures in these quartz veins and enables a new terminology in Spanish, with their equivalents in English and French as well as the selection of fluid inclusions microtermométricos for further studies. The study of fluid inclusions microtermométrico primaries, with the criterion of Family inclusions Fluidas allows determination of the conditions of formation of the veins. The homogenization temperatures (200 to 225Â ° C) and salinity (from 4 to 5 wt% NaCl equiv.) Exhibit excellent uniformity and relate to data from the literature on deposits epitermales. The fluids responsible for the formation of the veins of Cabo de Gata meteorite are moderately hot, aqueous, without gas and little salt. The study luminiscencias crystal is at the same time in a study of termoluminiscenica and catadoluminsicenica. This is the first time that applies a study of termoluminiscenica to cuarzos epitermales both in the delineation of curves intensidad-temperatura as in the autofotograífas emission. This is an entirely innovative method, which allows carografíar textures and demonstrate the relationship on the one hand, between the peaks of low temperature and structural flaws in the network of crystalline quartz and, moreover, among the peaks of high temperature chemical and defects. The termoluminiscenica is a good tool for prospecting for gold deposits, as a complement to the textural characterization, although there is no direct link between it and the contents of Au in quartz. As for the catodoluminiscenica, its relationship with the character at Au mineralized quartz is too indirect. It is a technique that is also applied to the study of fluid inclusions, especially the criterion of Families inclusions Fluidas.

Author: CARRILLO ROSÚA FRANCISCO JAVIER.
Year: 2004.
University: GRANADA [www.ugr.es].
Place of defense: FACULTAD DE CIENCIAS.
Place of preparation: INSTITUTO ANDALUZ DE CIENCIAS DE LA TIERRA (CSIC-U. GRANADA) - DEPARTAMENTO DE MINERALOGÍA Y PETROLOGÍA (F. CIENCIAS).

Summary: The epithermal deposit of Au-Cu of Palai-Islica (Carboneras, Almeria) is embedded into andesitas-dacitas calcoalcalinas neógenas presenting a strong hydrothermal alteration, associated with which are two types of mineralization: quartz veins with sulphides (more plentiful) and silicification mass. This deposit has been found enrichments metals (Au, Ag, Cu, etc.) concentrated on two levels between +40 and +50, and between -60 and -70 meters. Veins of quartz with sulphide: They consist of a network of quartz veins (+-chl, my, dol, gyup apt and sid) with abundant pyrite, chalcopyrite, sphalerite and galena. The minority are very diverse: aleacciones of Au-Ag, sulphides, sulfosales and telururos Ag, Bi minerals with .., thereby three stages: oxide increased pirítica = = higher base metal sulphides. The gold rush at the end of the stage pirítica while metals such as Ag, Cu, Zn .., they do during the base metals. The volcanic rock surrounding a hydrothermal alteration variable rate sericítico in proximal areas. The contents of Fe in chlorite, KyF in mica and F apatito have proved discriminating between alteration and mineralization, as well as indicators of the intensity of hydrothermal processes. The study IF in the veins and alteration associated indicates the existence of three types of fluids (KCl system H2O-NaCl-CaCl2-Â Do? -Â Do MgCl2?): 1-Baja-moderada salinity (5% + - 5% eq.NaCl) and Th variable (109-430Â ° C). 2-Salinity moderada-alta (10-30% eq.NaCl) and Th ranging between 200 and 430Â ° C. 3-Fluent hipersalino (36.6 -mayor 60% ep.NaCl) and high Th (265-largest 500Â ° C). The fluid I the most common, is indicative of a cooling process, whereas fluids II and III, associated with the event mineralizador more importantly, are possibly connected with a boil-induced boom hypersaline magmatic origin. The sulfide veins presented delta34S mostly between 4 and 9% (not compatible with equilibrium isotopic sulfuro-sulfato) to be originated from a hydrothermal fluid that has built and reduced S magmatic (delta34S volcanic: 9.5%). The values of delta18O (y87 Sr/86Sr) and filosilicatos of quartz veins and associated alteration indicate that the hydrothermal fluids are modified isotope seawater mixed with a certain amount of H2O of magmatic origin. Silicificacion mass: It consists of a metal spread in a totally silicified volcanic rock on the surface of the deposit. The phases are little metal abundant and diverse, with the only native gold ore. Surrounding the massive silicification appears a zone of alteration arcililítica with caolinita, pyrophyllite, mica +-interestratificado mica-esmectita and quartz, indicating conditions for formation of high acidity. The study indicates the existence IF fluid similar to those of type I and type II defined time for the veins, though Th and the maximum frequency of salinity are relatively high compared with those in the veins. Data from delta34S sulfides and sulfates are consistent with a balance between the two isotopic (300Â ° C) and which have been formed by a process of hydrolysis of SO2 from magmatic origin to be directly responsible for the high acidity. The values of delta 18O of curzo and filosilicatos are consistent with the hydrothermal fluids that led to the massive silicification and to a lesser extent, the associated hydrothermal alteration, had a dominant share of magmatic water. It is concluded that the veins features of a high-temperature epithermal deposit involving marine waters and to a lesser extent magmát 8 icas yd 3aa and an intermediate sulphidation, while the massive silicification has characteristics of epithermal deposit of high temperature and high sulphidation involving a character magmatic fluids.

Author: MACHUCA PEREZ FERNANDO ANTONIO.
Year: 2005.
University: POLITÉCNICA DE MADRID [www.upm.es].
Place of defense: ETS. INGENIEROS DE MINAS.
Place of preparation: ETS. INGENIEROS DE MINAS.

Summary: The control environment is a major challenge for mining, drilling operations as a unit, Blasting, Carguío Transportation are sources of emission of particulate matter PM10, which makes it necessary to control comply with environmental legislation. The increasing air pollution leads to the implementation of preventive measures, aimed at preventing the degradation of the air we breathe. The growing impact on the health of the population to live in an environment polluted has been quantified by respiratory diseases, premature deaths, besides air pollution causes the deterioration of equipment and facilities, and others. Air pollution measure through monitoring networks, is directly related to the baseline emissions when it exceeds the limits of the primary rules of air quality is imperative to develop a plan for reducing emissions, as well as a set strategies, action and measures to at least meet those standards in the long term. Develop a plan to address critical pollution episodes, which are those in which the concentration of pollutants reached critical levels due to the convergence of a number of factors adverse weather. Moreover, the plan incorporates environmental criteria for ensuring the sustainability of the mining operations in the future, once reached the targets for reducing emissions. The main objective is to enhance and maintain the Environmental Conditions of Rajo Chuquicamata:-Protecting the health of people - Get the most out of the operations-Complying with the regulations on environmental issues. - Development of new Mining Projects in the Area

Author: CASTAÑON FERNANDEZ CESAR.
Year: 2005.
University: OVIEDO [www.uniovi.es].
Place of defense: E.T.S.DE INGENIEROS DE MINAS.
Place of preparation: ESCUELA TECNICA SUPERIOR DE INGENIEROS DE MINAS DE OVIEDO.

Summary: The methods most commonly used for the calculation of Mineral Resources and Reserves bodies in tabular form or layer, as may be the method of polygons, the triangles and the method of sections, are major constraints in terms of its presentation three dimensions, and how to interpolate the results. As for the method of the blocks, the most commonly used today for all kinds of calculations of Resources and Reserves, in the case of narrow layers, it also has its limitacions in terms of the graphical representation of the layer as well as to the interpolation and the way to define the directions of the continuity of the mineralization. In this Doctoral Thesis deals with the research study of a new method for the calculation of Mineral Resources and Reserves Corps in Tabular, called Method Pentaédrico and addressing constraints before Reviewed for this type of ore bodies. The idea is innovative and is in the process of being patented, is part of a set of applications united in a single software package and is called RecMin (Mineral Resources-www.recmin.com-), which is discussed and treated in the Doctoral Thesis and has also been developed in its entirety by the author.

Author: RODRIGUEZ TERENTE LUIS MIGUEL.
Year: 2006.
University: OVIEDO [www.uniovi.es].
Place of defense: FACULLTAD DE GEOLOGIA.
Place of preparation: DEPARTAMENTO DE GEOLOGIA.

Summary: The gold deposit of Salave is located about 120 km. West of Oviedo in Asturias West, within the belt of Oscos. This reservoir is at the moment the largest gold reserve northwest of the Iberian peninsula remains untapped. The site is embedded in the granodiorite of Salave, which belongs to a group Porcía-Salave-Represas and are sealing the cabalgamiento the Mantle of Mondoñedo. At the western end of the granodiorite witnessed intense hydrothermal alteration with which relates the site. The microscopic and geochemical studies performed allow differentiate two types of mineralization. The first is molibdenífera and is composed almost exclusively of molybdenite, with some bismutinita in subvertical quartz veins embedded in the meta-sedimentario as in the intrusive. Later, it develops a second gold mineralization in nature and volumetrically much more important than the first. The hydrothermal fluids used the network of preexisting fractures in the granodiorite (about subvertical and others with soft buzamientos west) for the development and movement around them reemplazamientos and alterations. In areas near the fracture occurred intense reemplazaomientos albíticos and moscoviticos (phengita) from the granodiorite and intense carbonatización, which are the carriers of the mineralization. The feeding areas of hydrothermal fluid would fractures sub-verticales and since they would extend by fractures low angle, preferably towards the surface. These reemplazamientos pass laterally and gradually sericitazaciones, propilitizaciones and cloritizaciones of granodiorite. The old process moscovitización has been established at 295.4 +-1.6 Ma. The mineralization was caused by a fluid magmatic, acuoso-carbónico and aqueous both low salinity, with a minimum temperatures entrapment of approximately 350 ° C. This mineralization is composed of a first phase arsenical (which form the bulk of the reservoir) characterized by the presence of arsenopyrite rich in gold, pyrite and free gold, and a second phase antimonial, sobreimpuesta to first on a random basis and characterized by presence of estibinita, sulfosales of Sb-Pb-Ag, scheelita and native gold. For Salave proposes a model gold deposit embedded in intrusive igneous rocks formed during the late stages of a orógeno colisional.