No description available.

The Newer Granites of the Eastern Grampians form a distinctive suite of predominantly pink biotite granites, although white hornblende-bearing granites are also found. All of the plutons in the study area are composite bodies, although internal boundaries are rarely seen. They have been emplaced by stoping at crustal levels between 4.6 km, and are all currently exposed close to their roof zones. Biotite is the only mineral to show significant compositional variation, and does so in response to increasing subsolidus interaction with the fluid phase. All the pink granites are highly oxidised, and equilibrated at an fO2 of approximately 10-18 bars and temperature less than 400o C. The pink granites are highly chemically evolved, with marked enrichment in K, Si, Rb and HFS elements. The evolution of the fluid phase has played a dominant role in their geochemical evolution. The pink granites represent limited partial melts of depleted granulite, whereas the white (hornblende-bearing) granites have evolved from a melt of gabbroic lower crustal material. The granites were all emplaced between 419 and 404 Ma, and represent the transition between late, subduction-generated high-K magmas to melts generated by volatile degassing and heat focussing of a mantle source at pre-Caledonian basement lineaments.

Resumo: O stock granítico Serra do Barriga é pós-tectônico, polintrusivo, com 522,2l7.6Ma, apresenta tipos faciológicos de sienogranitos e monzogranitos inequigranulares a megaporfiríticos diferenciados pela coloração, aspectos composicionais e texturais. Investigou-se os tipos ornamentais Rosa Iracema, Rosa Olinda, Branco Savana e Branco Cristal Quartzo. Geoquimicamente são rochas peraluminosas, cálcio-alcalinas alto potássio formadas por magmas evoluídos, em ambiente orogênico pós-colisional. Transformações pós-magmáticas indicam origem por fracionamento de mesmo magma parental, acrescidos por pulso mais máfico (Rosa Olinda). A correlação entre índices físicos, resistência física e mecânica ocorre em função dos aspectos petrográficos. Os granitos rosas apresentam melhor desempenho para fachadas. Os parâmetros tecnológicos apresentados são superiores ou próximos aos valores limítrofes estabelecidos, qualificandoos como detentores de boa qualidade. No ataque químico os granitos reagem de forma semelhante, com variações cromáticas e alterações minerais sutis, indicando serem resistentes. Entretanto granitos rosas apresentam maior perda de brilho e corrosão mineral em contato com ácidos cítrico e clorídrico, reagentes mais destrutivos. Embora resistentes, deve-se evitar exposições prolongadas dos granitos estudados à substâncias contendo ácidos. Estes granitos são adequados para fins ornamentais, sendo os rosas (Iracema e Olinda) altamente resistentes, eficientes para aplicação em pisos e fachadas de ambientes interiores e exteriores, com cuidados na manutenção. / Abstract: The polyintrusive Serra do Barriga granitic stock is post-tectonic, with a 522.2 l 7.6 Ma age. It presents inequigranular to megaporphyritic syenogranitic and monzogranitic faciological types differing by collor, composition, and textural aspects. In this research we investigated the following ornamental types: Rosa Iracema, Rosa Olinda, Branco Savana, and Branco Cristal Quartzo. Geochemically these are peraluminous, high-potassium calcium-alkaline rocks formed from highly evolved magmas in a post-collisional orogenic environment. Late-magmatic transformations indicate an origin by fractioning of a unique parental magma, added by a mafic pulse (Rosa Olinda). The correlation between the physical indices and the physical and mechanic resistance were done as a function of the petrographycal analyses. The technological parameters obtained are higher or close to the bordering values, which characterises these rocks as good quality ones. The granites react to the chemical attack by slight both chromatic variations and mineral alterations, indicating to be resistant rocks. The rose colored granites, however, show a greater alteration when in contact with the more destructive citric and chloridric acids. Although resistant, one sends regards to prevent expositions to acid-bearing substances. The granites of the Serra do Barriga stock are adequate for ornamental use, being the Rosa Iracema and Rosa Olinda types highly efficient for both floor pavement and wall covering, with care in the maintenance. / Orientador: Antonio Carlos Artur / Coorientador: José de Araújo Nogueira Neto / Banca: Tamar Milca Bortolozzo Galembeck / Banca: Antenor Braga Paraguassú / Banca: Eleno de Paula Rodrigues / Banca: Maria de Fátima Bessa Torquato / Doutor

No description available.

Τα δείγματα που μελετήθηκαν στην παρούσα διπλωματική εργασία προέρχονται από τη θέση Τούμπα - Ανθοβούνι, στις ΒΔ-Δ-ΝΔ υπώρειες του όρους Βαρνούντα του νομού Φλώρινας. Στην περιοχή αυτή κατασκευάστηκε Αιολικό Πάρκο, όπου πραγματοποιήθηκαν συνολικά τριάντα τέσσερις γεωτρήσεις για την εγκατάσταση ανεμογεννητριών. Η ευρύτερη περιοχή τη Φλώρινας ανήκει γεωλογικά στην Πελαγονική Ζώνη και δομείται γενικά από γνευσίους και ημι-μεταμορφωμένα πετρώματα. Στα πλαίσια αυτής της εργασίας εκτελέστηκαν εργαστηριακές δοκιμές σε δείγματα βραχωδών σχηματισμών. Στο τρίτο κεφάλαιο περιγράφονται αναλυτικά οι δοκιμές που χρησιμοποιήθηκαν. Μετά τη συλλογή τους, τα βραχώδη δείγματα διαμορφώθηκαν σε κυλινδρικό σχήμα, διαμέτρου 53 mm με εργαστηριακή καροταρία. Τα άκρα των δοκιμίων κόπηκαν σε μήκη ανάλογα των προβλεπόμενων εργαστηριακών δοκιμών. Οι βάσεις τους λειάνθηκαν ώστε να είναι κάθετες προς τον μεγάλο άξονα του δοκιμίου. Στο επόμενο κεφάλαιο αναφέρεται η δειγματοληψία των γρανιτών. Η θέση δειγματοληψίας εντοπίζεται στην περιοχή Πισοδερίου, που βρίσκεται στο νομό Φλώρινας. Επίσης, στην ενότητα αυτή περιγράφονται και οι δύο τρόποι διαμόρφωσης των δειγμάτων μετά από τη δειγματοληψία με το δειγματοληπτικό γεωτρύπανο. Στο εργαστήριο εξετάστηκαν τα φυσικά και τα μηχανικά χαρακτηριστικά των γρανιτών. Οι εργαστηριακές αυτές δοκιμές βραχομηχανικής γίνονται για τον προσδιορισμό της πυκνότητας, του λόγου κενών, του πορώδους, και της αντοχής των γρανιτών σε μοναξονική ανεμπόδιστη θλίψη. Στο κεφάλαιο αυτό, τα αποτελέσματα από κάθε εργαστηριακή δοκιμή προβάλλονται σε πίνακες, καθένας από τους πίνακες αυτούς αναφέρεται και σε μία άλλη δοκιμή. Ο αριθμός των δοκίμια που χρησιμοποιήθηκαν για κάθε δοκιμή είναι ο εξής: για τον προσδιορισμός των φυσικών παραμέτρων οκτώ (8) δοκίμια, για τον προσδιορισμός των δυναμικών παραμέτρων έξι (6) δοκίμια και για τον προσδιορισμός των παραμέτρων αντοχής χρειάστηκαν δέκα (10) δοκίμια. Στο έκτο κεφάλαιο συγκεντρώνονται σε ένα πίνακα όλα τα αποτελέσματα από όλες τις δοκιμές που εκτελέστηκαν. Οι δοκιμές αυτές πραγματοποιήθηκαν στους γνεύσιους, γρανίτες και γρανιτογνεύσιους. / The samples that have been studied in the current diplomatic project come from Toumpa-Anthovouni, at the NW-W-SW foot of the mountain Varnouda of county Florina. At these area was built a wind park, where had taken place thirty-four drilling for the installing of the wind turbines. The wider area of Florina geologically belongs to the Pelagonian zone and is generally structured by gneisses semi-transformed stones. Within the project laboratory testing have taken place on samples of rock formations. In the third chapter the testing that were used are described in depth. After their collection, the rock samples were reformed into cylindrical shape, diameter 53mm by laboratory karotaria. The ends of the samples were cut into lengths as the planned laboratory tests. Their bases were planished to be perpendicular to the long axis of the specimen. In the next chapter the sampling of the granites are mentioned. The place of the sampling is located in the area of Pisoderio, which belongs to the county Florina. Also, on that section both two ways of forming the samples after the sampling by sampling rig are described. At the laboratory the natural and mechanical characteristics of the granites were examined. These laboratory tests on rock mechanics have been done for the determination of the density, the ratio of spaces, the porosity and the durability of the granites under uniaxial unconfined compression. In this chapter, the results from each laboratory test are displayed on tables, each one of them mentions a different test. The number of the samples that were used for each test are the following; for the determination of the natural parameters eight (8) samples, for the determination of the dynamic parameters six (6) samples and for the determination of the durability parameters were used ten (10) samples. In the sixth chapter all the results from all the tests that have been executed are gathered in one table. These tests took place in gneiss and granites.

No presente trabalho abordou-se inicialmente as principais características da indústria de rochas ornamentais, a lavra das jazidas e o beneficiamento, compreendendo a serragem, semitransformação e transformação até os tipos mais importantes de produtos que são normalmente comercializados. Em seguida, estudou-se as rochas ornamentais desde seus tipos, suas cores , brilhos, suas classificações relativas a gênese, estruturas e valor comercial Foi dada ênfase especial as cores tanto das rochas como dos ambientes onde elas serão aplicadas, lembrando a influência psicológica das cores com relação aos seres humanos. Apresentou-se proposta de identificação das cores utilizando recursos atuais da informática, além de uma proposta de criação de um Banco de Dados, com informações específicas de interesse para os projetos de engenharia e arquitetura. Como exemplo, analisou-se uma aplicação onde utilizou-se o Banco de Dados que foi criado, além de conceitos importantes relativos a uma intervenção arquitetônica. / In present work, initially was approached the main characteristics of the dimension stones industry, explotation of the deposits and the processing, understanding the sawing semitransformation and transformation, as well the types most important of products that are normally commercialized. After that, one studied the dimension stones from the types, colors and brightness to the relative classifications geneses, strutures and commercial value. It was given special emphasis to the colors of the rocks as well as the of environments where they will be applied, remembering the psychological influence of the colors related to the human beings. One presented proposal of identification of colors identification using current resources of computer science, beyond a proposal of creation of a data base, with information of interest for the projects of engineering and architecture. This work presents, as example, an application, using the data base created, as well as relative important concepts to an architectural intervention.

La croûte de granitoïdes de la Terre Primitive la plus ancienne qui ait été préservée remonte au Paleoarchéen et se compose principalement de granitoïdes sodiques tonalite-trondhjémite-granodiorite (TTG) qui se sont formés par fusion partielle de métabasaltes hydratés. En revanche, les granites (stricto sensu) sont en général postérieurs aux TTG et apparaissent tardivement dans les cratons anciens.Cependant, l’existence de zircons Hadéens préservant des suites d’inclusions minérales qui sont compatibles avec la cristallisation à partir d’un magma granitique peralumineux, indique que les roches granitiques faisaient aussi partie de la croûte felsique de la Terre Primitive; même si nous n’avons pas de preuves directes et que cette dernière n’ait pas conservée. Dans cette thèse, je présente une variété inhabituelle de granites et rhyolites peralumineux qui sont marqués par un forte teneur en K2O et une faible teneur en CaO et qui possèdent du rutile. Ces roches sont situées dans le conglomérat basal du Groupe du Moodies (Afrique du Sud). Elles défient la vision commune que l’on a de l’évolution des cratons Archéens puisqu’elles ont été produites en même temps que des magmas TTG, pendant trois cycles magmatiques qui ont affectés la ceinture de roches vertes de Barberton (CRVB). Ces roches ont été par la suite mises en place, comme galets, dans un conglomérat plus jeune.L’étude des inclusions minérales localisées dans des zircons présents dans les granites et les rhyolites qui font le sujet de cette étude, montre que les inclusions de feldspaths alcalins sont plus abondantes que les inclusions de plagioclases et démontre que les principales caractéristiques de ces granites, c’est à dire qu’ils sont riches en K et pauvres en Ca, ont une signature magmatique. La signature isotopique de l’oxygène de ces zircons révèle que ceux-ci ont conservé la valeur du δ18O du magma à partir duquel les granites se sont formés. De plus ceci montre que la valeur du δ18O de la source des granites etait proche de celle de TTG contemporains. La poursuite de l’étude des zircons montre que leur système isotopique Lu-Hf reflète la signature crustale du magma dans lequel ils ont cru. L’étude Sm-Nd des granites et rhyolites indique que l’âge minimum du protolithe de leur source est de près de 3,9 milliards d’années, ce qui est en accord avec la signature Lu-Hf des zircons. De plus, je montre dans cette thèse que le caractère peralumineux des granites et des rhyolites, avec leur forte teneur en Sr et basse teneur en Ca associés à leurs Eu / Eu * ~ 1, est une conséquence de la fusion partielle de phengite dans une source métagrauwacke à des pressions supérieures a celle de la stabilité du plagioclase. Mon travail montre donc que des granites peralumineux riches en K et pauvres en Ca ont été générés durant le Paléo et Méso-Archéen, aux côtés des TTG sodiques, par la fusion partielle de sédiments, à haute pression. Non seulement ce processus a démontré la capacité de la Terre Primitive à recycler du matériel relativement jeune et ce, dès 3,9 milliards d’années; mais il a également contribué à chaque épisode de croissance crustale à travers le Paleo- et Méso-Archéen dans la CRVB, malgré l’absence de pluton mis en place à des profondeurs identiques à celles des TTG. / Earth’s oldest preserved granitoid crust dates back to the Paleoarchean and consists predominantly of sodic tonalite-trondhjemite-granodiorite (TTG) granitoids that arose through the partial melting of hydrated metabasalts. In contrast, granites (sensu stricto) typically postdate the TTG and appear late in the plutonic record of the old cratons. However, the existence of Hadean zircons with mineral inclusion suites that are consistent with crystallization from peraluminous granitic magmas indicates that granitic rocks formed part of the earliest felsic crust; although we have direct evidence, this earliest felsic crust is not preserved. In this PhD I present an unusual variety of markedly CaO-poor, K2O-rich, rutile-bearing, peraluminous granite and rhyolite that are located in the basal conglomerate of the Moodies Group (South Africa). These rocks challenge the common view of the Archean craton evolution as they were produced concurrently with TTG magmas during three magmatic cycles in the Barberton Greenstone Belt (BGB) and were later emplaced, as clasts, in a younger conglomerate. The study of mineral inclusions located in the zircons present within the granites and rhyolites, shows that alkali feldspar inclusions are abundant relative to plagioclase inclusions and demonstrates that the main characteristics of these granites, i.e. they are K-rich and Ca-poor, are a magmatic signature. The oxygen isotope signature of these zircon grains reveals that the zircons have preserved the δ18O value of the magma from which the granites originated and that the source of the granites had a magmatic oxygen isotope value close to the one of the regional coeval TTG. Further study of the zircons shows that their Lu-Hf isotopic system reflects the crustal signature of the magma into which they grew. Sm-Nd study of the granites and rhyolites whole rock indicates that the minimum age of the source’s protolith of the granites and rhyolites is close to 3.9 billion years, which is in agreement with the zircons’ Lu-Hf signature. Additionally I show in this thesis that the peraluminous character of the granites and rhyolites, along with their high Sr and low Ca content associated to their Eu/ Eu* ~ 1 is a consequence of phengite melting in a metagreywacke source at pressures in excess of plagioclase stability. My work therefore illustrates that K-rich, Ca-poor peraluminous granites were generated in the Paleo and Meso Archean, alongside with the sodic TTG, through partial melting of sediments at high pressures. Not only has this process demonstrated the ability of the early Earth to recycle relatively young material since 3.9 billions years ago, but it has also contributed to each episode of continental crustal growth through the Paleoarchean to Mesoarchean in the BGB, despite leaving no plutonic record at the typical mid-crustal level of exposure that the TTG plutons around the belt represent.

No presente trabalho abordou-se inicialmente as principais características da indústria de rochas ornamentais, a lavra das jazidas e o beneficiamento, compreendendo a serragem, semitransformação e transformação até os tipos mais importantes de produtos que são normalmente comercializados. Em seguida, estudou-se as rochas ornamentais desde seus tipos, suas cores , brilhos, suas classificações relativas a gênese, estruturas e valor comercial Foi dada ênfase especial as cores tanto das rochas como dos ambientes onde elas serão aplicadas, lembrando a influência psicológica das cores com relação aos seres humanos. Apresentou-se proposta de identificação das cores utilizando recursos atuais da informática, além de uma proposta de criação de um Banco de Dados, com informações específicas de interesse para os projetos de engenharia e arquitetura. Como exemplo, analisou-se uma aplicação onde utilizou-se o Banco de Dados que foi criado, além de conceitos importantes relativos a uma intervenção arquitetônica. / In present work, initially was approached the main characteristics of the dimension stones industry, explotation of the deposits and the processing, understanding the sawing semitransformation and transformation, as well the types most important of products that are normally commercialized. After that, one studied the dimension stones from the types, colors and brightness to the relative classifications geneses, strutures and commercial value. It was given special emphasis to the colors of the rocks as well as the of environments where they will be applied, remembering the psychological influence of the colors related to the human beings. One presented proposal of identification of colors identification using current resources of computer science, beyond a proposal of creation of a data base, with information of interest for the projects of engineering and architecture. This work presents, as example, an application, using the data base created, as well as relative important concepts to an architectural intervention.

High Purity Quartz (HPQ; quartz containing less than 50 ppm trace elements) is of increasing economic significance due to its use in certain high-tech components (computer chip/semiconductor manufacture) and in green technologies (silicon wafer production). Current HPQ deposits (hydrothermal veins/leuco-granites/alaskites) are rare and volumetrically small. Unless significant new deposits are found, increasing demand will raise its prices, elevating the strategic nature of this limited commodity. The large volumes and simple mineralogy of pegmatites and the high chemical purity of their constituents make them an attractive target for HPQ. PhD studies are being carried out on quartz from the Evje-Iveland pegmatite field of the Bamble-Evje pegmatite cluster, southern Norway. The area was targeted due to its well constrained geological setting and previously identified potential for HPQ. The aim of the investigation is to develop exploration tools for HPQ by determining the genetic history of the pegmatites and mode of HPQ formation. The study is focussing on 7 pegmatites and their country rocks. Each shows typical pegmatite zonation, with quartz/feldspar intergrowths at the margins, a massive quartz core and a variety of accessory (including REE-bearing) phases. The proximal Høvringsvatnet granite was previously suggested to have supplied late-stage, highly fractionated melts to form the pegmatites. However, from their trace element systematics (no relationship was observed between trace element content and degree of fractionation in each pegmatite body), and a difference in U/Pb age of approximately 70 Ma, the pegmatites cannot be related to the granites. From field evidence (corroborated by geochemical modelling) the pegmatites formed by ‘in situ’ anatexis of country rocks; some locally, some from distal sources. Some pegmatites contain brecciated feldspar and replacement quartz. From LA-ICP-MS analyses, hydrothermal quartz, compared with magmatic quartz, typically contains lower quantities of trace elements. Hydrothermal material shows relatively elevated levels of Al and Li, low Ge and a complete absence of Ti, indicating relatively low temperature hydrothermal formation. Different quartz domains (from SEM-CL imaging) show distinct δ18O values; late stage low trace element zones show values consistent with meteorically derived fluids. In situ LA-ICP-MS studies will provide further information about the characteristics of the fluids which have replaced/refined magmatic quartz to form HPQ. This beneficiation process is a potential mechanism for the generation of economically significant HPQ deposits.

Este trabalho apresenta uma contribuição experimental cujo objetivo é fornecer elementos para o aprimoramento tecnológico das etapas de polimento de rochas ornamentais. Alguns aspectos da tribologia, ramo do conhecimento amplamente utilizado nas engenharias mecânica e de materiais, foram transferidos para o estudo do polimento de rochas ornamentais e subsidiaram a investigação da interação do tribossistema composto pela rocha, pelo abrasivo e por condições operacionais. Foi desenvolvido um equipamento em laboratório que possibilitou a simulação do processo de polimento, em diversas condições operacionais, considerando as variáveis tempo, velocidade de rotação e intensidade das cargas aplicadas. Foram comparados polimentos, em condições industrial e laboratorial de rochas graníticas, visando estabelecer as influências das suas características composicionais, texturais e estruturais no processo. Os resultados permitiram definir as condições ideais para a obtenção de melhor qualidade no brilho das rochas e representa uma contribuição tanto para o entendimento do processo de polimento propriamente dito como também para a otimização do processo industrial. / This work shows an experimental contribution which goal is to provide elements to the technological improvement of each step of dimension stones polishing. Some aspects of tribology, a discipline of mechanical and material engineering, has been used on the research of dimension stones polishing and has supported the investigation of the interaction of the tribosystem composed of rock, abrasive and operational conditions. For this research, a device was developed in the lab in order to make possible the simulation of the polishing process at different operational conditions, considering the variables time, rotation speed, and intensity of the loads applied. The polishing of granite rocks at industrial and lab conditions has been compared, aiming at determining the influence of each rock characteristics such as mineral composition, texture and structure during the process. The results allowed for the definition of the ideal conditions to obtain the best quality of rock brightness and they represent a contribution to the understanding of the polishing process itself as well as provide an optimization of the industrial process.