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1
Flatley, Kerin. "Granite Butterfly." Digital Archive @ GSU, 2009. http://digitalarchive.gsu.edu/english_diss/45.
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ABSTRACT Granite Butterfly is a novel about three women—grandmother, mother, and daughter—and the unusual attachments that break apart their family. Tuula Laine is a Rockport, Massachusetts, native of Finnish descent, whose parents moved to Cape Ann for work in the area’s granite quarries. Her life changes one afternoon when her son Henri, a brilliant surgeon who has never seriously dated anyone before, visits with his pregnant girlfriend, Coreen. Tuula immediately senses that Coreen not the right match for him in terms of age, education, or temperament, and as the couple separates and unites over the course of one summer, Tuula witnesses, for the first time, the pattern of desire and abandonment that will define their relationship. By the time Tuula’s granddaughter, Suvi, is fourteen years old, she, too, has established a destructive relationship pattern with Coreen: whenever Coreen and Henri separate, Suvi’s mother clings to her until they develop a bond closer to that of sisters than a mother and child. In the final movement of the novel, this bond, and the bond between Suvi’s parents, is finally put to the test. Granite is cut into precise blocks—dynamite is never used, lest it shatter the stone. In a few short weeks, the Laine family is pulled apart, but unlike with quarrying, there is no way to divide them in a careful manner, no way to detach them that isn’t violent and abrupt, no way to predict, or guide, where they will split.
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Villaros, Arnaud. "Petrogenesis of S-type granites : the example of the Cape Granite Suite." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/4015.
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Thesis (PhD (Earth Sciences))--University of Stellenbosch, 2010.ENGLISH SUMMARY: S-type granite intrusions are extremely common in the continental crust and form from the partial melting of metasediments. Compositions of S-type granite range from leucogranite to granodiorite and have trace element contents that globally increase with increasing maficity (Fe + Mg). Models proposed for the formation of S-type granite do not answer satisfactorily all petrological and compositional requirements. In this study, S-type granite of the Cape Granite Suite (CGS), South Africa is used to discriminate between potential sources of compositional variation. Experimental studies show that melt produced from the partial melting of sediment is exclusively leucocratic. On this basis, the entrainment of up to 20 wt.% of peritectic garnet within S-type melt can be established to produce the observed major element variations. S-type CGS locally contains garnet. This garnet is in equilibrium with granite composition at P-T conditions (5kb and 750 C for the core of the garnet and 3kb and 720 C for the rim) well below conditions recorded by xenoliths from the same granite (10 kb and 850 C from a metabasite). From this result it seems that the originally entrained garnet no longer exists in the Stype CGS and it have been replaced by newly formed minerals (garnet, cordierite and biotite). Considering the short time necessary to emplace granites (about 100 000 years), it appears that garnet has been compositionnally re-equilibrated through a dissolution-precipitation process. The study of trace element variations in S-type CGS shows that most leucocratic compositions are undersaturated in Zr and Ce compared to predictions from experimental models for dissolution of accessory zircon and monazite in their source regions. Thus, S-type melts are likely to be formed in disequilibrium with respect to accessory phase stability. As a result the observed increase in trace element content with increasing maficity indicates that accessory minerals such as zircon and monazite are co-entrained with peritectic garnet in melt to produce the observed trace element variation in S-type granite. Trace element disequilibrium in the CGS S-type granitoids requires particularly short times of residence of melt within the source region. Together, these results provide for the first time, a fully comprehensive model for major and trace elements variations. Compositional variation in CGS S-type granite results from source processes by a selective entrainment of peritectic and accessory minerals. After entrainment, these minerals are likely to be re-equilibrated within the magma, through a dissolution-reprecipitation process. In addition, it appears that the construction of large S-type granitic bodies occurs through successive addition of magma batches of different composition that originates directly from the source region.
AFRIKAANSE OPSOMMING: S-tipe granietinstrusies is baie algemeen in die kontinentale kors en vorm deur die gedeeltelike smelting van metasedimente. Samestellings van S-tipe graniete strek vanaf leukograniet tot granodioriet en het spoorelementsamestellings wat global toeneem met ’n toenemende mafiese component (Fe + Mg). Modelle wat voorgestel is vir die formasie van S-tipe graniete beantwoord nie bevredigend al die petrologiese en komposisionele benodigdhede nie. In hierdie studie word S-tipe graniete van die Kaapse Graniet Suite (CGS), Suid Afrika, gebruik om te diskrimineer tussen potensiele bronne van komposisionele variasie. Eksperimentele studies wys dat smelt, geproduseer van die gedeeltelike smelting van sedimente, uitsluitlik leukokraties is. Op hierdie basis kan bewys word, dat die optel-en-meevoering van tot 20 wt% van peritektiese granaat in S-tipe smelt, die waargeneemde hoofelement variasies kan produseer. S-tipe CGS bevat lokale granaat. Hierdie granaat is in ekwilibrium met die graniet samestelling by P-T kondisies (5kb en 750circC vir die kern van die granaat en 3kb en 720circC vir die rand) ver onder kondisies waargeneem by xenoliete van dieselfde granite (10kb en 850circC van ’n metabasiet). Van hierdie resultaat kan afgelei word dat die oorspronklike opgetel-en-meegevoerde graniet bestaan nie meer in die S-tipe CGS en dat dit vervang is deur nuutgevormde minerale (granaat, kordieriet en biotiet). As in ag geneem word die kort tyd wat nodig is om graniete in te plaas (omtrent 100 000 jaar), wil dit voorkom dat granaat se samestelling geherekwilibreer word deur ’n oplossings-presipitasie proses. Die studie van spoorelement variasies in S-tipe CGS wys dat meeste leukokratiese samestellings is onderversadig in Zr en Ce in vergelyking met voorspellings deur eksperimentele modelle vir die oplossing van bykomstige zircon en monasiet in hulle brongebiede. Dus is S-tipe smelte meer geneig om gevorm te word in disekwilibrium in verhouding tot bykomstige mineraalstabilileit. Met die gevolg is dat die waargenome toename in spoorelementinhoud met toename in mafiese component wys dat bykomstige minerale, soos zirkoon en monasiet, word saam opgetel-enmeegevoer met peritektiese granaat in smelt om die waargenome spoorelement variasie in S-tipe graniete te verklaar. Spoorelement disekwilibrium in die CGS S-tipe granitoide benodig veral kort tye van residensie van die smelt binne die brongebied. Saam gee hierdie resultate vir die eerste keer ’n algehele antwoord vir hoof- en spoorelement variasies. Variasie in samestelling in CGS S-tipe graniete is die resultaat van bronprosesse deur ’n selektiewe optel-en-meevoer van peritektiese en bykomstige minerale. Na die optel-en-meevoer van hierdie minerale word hulle geherekwilibreer binne die magma deur ’n oplossings-presipitasie proses. Addisioneel wil dit voorkom of die konstruksie van groot S-tipe granietliggame plaasvind deur opeenvolgende toevoegings van magma lotte van verskillende samestellings wat direk uit die brongebied kom.
3
England, Richard W. "The ascent and emplacement of granitic magma : the Northern Arran granite." Thesis, Durham University, 1988. http://etheses.dur.ac.uk/6609/.
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This thesis is a study of the mechanisms by which granitic magmas rise through the crust to be empiaced at a level above their source, with particular reference to diapirisni. and how these mechanisms may be analysed by combined structural and petrological studies. The Northern Arran granite is used as an example of how this problem may be approached. The Northern Arran granite is a two component granite of Tertiary age intruded into structurally heterogeneous upper crustal rocks under regional tension. A synform concentric to the granite, synchronous with the development of a narrow thermal aureole, records the vertical ascent of a single body of magma with a hemispherical upper surface. Post ascent, radial expansion of this body, indicated by flattening strains parallel to its surface and superimposed on the concentric synform records a change in shape of the pluton. This was permitted by the reactivation of an existing fault which the pluton intersected during its ascent. Petrological studies of the outer coarse unit of the northern granite indicate that it is a single body of magma derived by differentiation of a crustally contaminated basaltic source. Theoretical modelling of the crystallisation of the coarse granite shows that textural and chemical variations, are consistent with solidification by sidewall crystallisation (liquid fractionation) but not fractional crystallisation. The inner (younger) fine granite is also a single body of magma derived from the same or a similar source as the coarse granite. The sharp undeformed contacts between the coarse and fine granites and the presence of internal sheets in the fine granite parallel to its contacts with the coarse granite are consistent with emplacement of the fine granite as a series of pulses which filled a propagating ring dyke fracture within the coarse granite. Theoretical modelling of the ascent of the coarse granite using the Hot Stokes equation indicates that bouyancy driven ascent aided by a reduction in wall rock viscosity controlled by the rate of heat loss of from the granite is a viable ascent mechanism. The patterns of strain in the aureole of the Northern Arran granite result from the ascent and emplacement of a single diapiric body. They provide examples of the types of structure which may be used to recognise and distinguish between diapiric ascent and radial expansion. This has important implications for the study of ballooning diapirs. The reactivation of an existing fault system during emplacement suggests that existing crustal structure can influence the final geometry of an intrusive body. It is shown that the complete evolution of the Northern Arran granite can be determined using a combination of structural and petrological data. Structural data provides constraints on the later stages of ascent and the emplacement of granitic plutons. Petrological data can be used to constrain the origin, early stages of ascent and the crystallisation of a magma body.
4
Miller, James Thomas Ph D. Massachusetts Institute of Technology. "Crack coalescence in granite." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/47771.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2008.Includes bibliographical references.
This thesis experimentally investigates crack coalescence in prismatic Barre Granite specimens with two pre-cut, open flaws under uniaxial compression. Using a high-speed video system, crack initiation, propagation, and coalescence are observed. Flaw geometries are chosen to allow one to compare the results with those of studies in other materials as well as to better understand fracturing and coalescence processes. Specifically, the effect of ligament length (L), flaw inclination angle (p3), and bridging angle (a) on coalescence is investigated. The same crack types as in other materials are observed. Coalescence patterns observed fit into a previously developed framework (for molded gypsum and Carrara marble) with the exception of one new coalescence pattern. Crack processes and coalescence patterns suggest a more tensile behavior as grain size increases from gypsum to marble to granite. Similar to previous work in marble and granite, white patches are observed during compression tests. These white patches can be categorized as either diffuse or linear, with linear white patches further subdivided into two more types, namely boundary-following and through-going. The white patches are essentially process zones. The effect of water pressure on coalescence pattern is also investigated. Flaw water pressure is seen to affect coalescence in granite, although further work is needed.
by James Thomas Miller.
S.M.
5
Wu, Jimin. "Description quantitative et modélisation de la texture d'un granite : granite de Guéret (France)." Bordeaux 1, 1995. http://www.theses.fr/1995BOR10600.
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Le travail présenté consiste en une analyse de la densité, de la taille, de la forme et de la distribution spatiale des principaux minéraux (quartz, feldspaths, biotite et muscovite) du granite de Guéret (France). Après un rappel des méthodes et techniques de l'analyse d'images, on développe trois méthodes d'acquisition d'images : méthode macro-photographique sur lames minces, méthode de saisie directe en microscopie et méthode semi-automatique par dessin manuel de la texture. Les paramètres mesures font l'objet d'une analyse statistique et d'une analyse critique par comparaison des résultats obtenus au moyen de chacune des méthodes. Les lois weibull, de laplace-gauss, et de poisson sont respectivement utilisées dans la modélisation de la distribution des tailles, de la forme et de la distribution spatiale des mineraux. Une analyse détaillée de la taille et de la distribution spatiale de biotite met en évidence une orientation privilégiée de la biotite parallèlement à une famille de fracture géometriquement bien identifiée. L'analyse des modèles de la distribution spatiale des minéraux se fait par adéquation de leur distribution expérimentale a une loi de poisson.
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Bland, A. M. "The geology of the granites of Western Jersey, with particular reference to the south-west granite complex." Thesis, Oxford Brookes University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355623.
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Graham, Nigel Thomas. "Fabric studies in the Galway Granite, Ireland." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362002.
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Al-Hafdh, Nabeel Mustafa Suliman. "The alteration petrology of the Cheviot granite." Thesis, University of Newcastle Upon Tyne, 1985. http://hdl.handle.net/10443/1866.
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The Cheviot Granite complex is a high-level pluton made up of six intrusive phases intruded into a pile of andesites of very similar composition to the bulk of the plutonics. The whole represents the eroded remnant of a lower Devonian volcano, erupted immediately after the continental collision that destroyed the Iapetus Ocean. The igneous history comprises two igneous cycles, both starting with basic granodiorite and including a late porphyritic ring dyke. The two cycles can be distinguished geochemically using Zr and K contents. Fractionation during each cycle involved precipitation of a biotite diorite cumulate. The second cycle ends with a highly evolved leucocratic microgranite. The geochemistry shows a rather shoshonitic - chemistry to the series, and trace elements are consistent with an immediately post-collisional origin. Hydrothermal alteration occurs in two phases, one associated in space and time with the porphyritic granodiorite of the first igneous cycle, and the other with that of the s~cond cycle. In both systems both potassic and sericitic alteration assemblages are found, and there is a wide development of propylitic alteration around these higher temperature zones. The two hydrothermal phases can be distinguished by the abundance of tourmaline in sericitic and propylitic rocks of the second cycle, and the abundance of calcium (mostly as calcite) in the sericitic rocks of the first phase. Geochemical flux calculations show that silica has been widely introduced to the granite during the alteration (in amounts up to 10\) and Ca and Sr removed. Other element fluxes are more complex, and may be coupled together. Comparison with other granites of N England and S Scotland shows that the Loch Doon complex and the Shap granite are very similar to Cheviot, that the Criffell Dalbeattie granite has a very similar early phase but diverges later, and that the Skiddaw, Weardale and Cairnsmore of Fleet granites are very different from Cheviot, being essentially granitic rather than granodioritic.
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Lee, In-Keun. "Mechanical behaviour of compacted decomposed granite soil." Thesis, Online version, 1991. http://ethos.bl.uk/OrderDetails.do?did=1&uin=uk.bl.ethos.292710.
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Kruszewska, Barbara M. "The xenolithic suite of the Strontian Granite." Thesis, London Metropolitan University, 1990. http://repository.londonmet.ac.uk/3153/.
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The Strontian Granite in Argyllshire. is a composite pluton of late Caledonian age, emplaced into Moinian psammitic and pelitic rocks. It is composed of an outer tonalitic granodiorite (dated at 435 Ma.) passing into a porphyritic granodioritic, both xenolithic, and intruded by a younger alkali granite (ca. 400 Ma.).
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ETZI, ANDREINA. "Granite By-Products for inverted pavement technique." Doctoral thesis, Università degli Studi di Cagliari, 2016. http://hdl.handle.net/11584/266695.
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As mentioned by Sardinia Region: ''Sustainable Development is what satisfies present's needs
without shattering those of future generations, thanks to smart use of environmental resources
and without waists''. This research aims to use a current resource available in high quantities
in Sardinia to optimize the uses of the extracted materials and not to take just advantage of the
Region. The mining activity in Sardinia, which is very important since ‘60s, during these
years, has produced huge amounts of granite by-products. The ornamental use of granite is an
important money source for Sardinia. Unfortunately, as the virgin material extracted must
have high aesthetic qualities, many rock blocks are rejected. This research has the aim of
making the most of the material stored in a quarry sites and of optimizing the uses of resource
stone examined.
The target is the use of granite by-products as material with high mechanical featured to be
used for road pavements, from the foundation to surface. This research gives you the
opportunity to make the most of regional resources, to minimize the thickness of asphalt,
reducing the maintenance and realization costs. This is a good start for the Island to make
money of something easy to export.
Granite by-products will be used for the construction of innovative road pavement design.
The Inverted Pavement Technique, studied and developed in South Africa since 1950, is
going to be used for road infrastructure. In particular, I have focused the attention on the
behavior of granular base layer. Thanks to this technique is actually possible to take
advantage of mechanical features of base layer, creating base layers that assure high and long
lasting performances with almost zero environmental costs. The Project is finalized to a
sustainable design by using resources, considered as waste so far, present in the Sardinian
Land and the minimal use of exhaustible and expensive row materials as asphalt layers.
The increasing costs of petrol products and their limited availability leaded to find alternative
solutions to flexible infrastructure everywhere in the world.
Another target was to make sure that European and South African Regulation matched
regarding granular aggregates. Through laboratory testing physical, chemical, and mechanical
features of granite by-products were analyzed comparing to Dolerite, used in South Africa in
the Inverted Pavement Technique.
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KATO, Takenori, Kazuhiro SUZUKI, Taisei MORISHITA, and Chinatsu YONEZAWA. "CHIME ages of zircons in granitic gneiss and granite from Samilpo, southeastern Democratic People's Republic of Korea." Dept. of Earth and Planetary Sciences, Nagoya University, 1997. http://hdl.handle.net/2237/2835.
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Linklater, Michael Anthony Leonard Flanders. "The exploration for and possible genesis of, some Archaean granite/gneiss-hosted gold deposits in the Pietersburg granite-greenstone terrane." Thesis, Rhodes University, 1992. http://hdl.handle.net/10962/d1005557.
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Abstract The gold mineralization event within Archaean granite-greenstone terranes occurred during the late Archaean, and followed the intrusion of syn- to late-tectonic granitic plutons into previously deformed greenstone belts. An Archaean granite/gneiss-hosted gold deposit, in terms of this project, is classified as having a gold-assay cutoff of 1g/metric ton over widths of at least several metres, or higher grades over narrower widths and/or verbal descriptions that indicate such values. Fluid inclusion studies and isotopic data identify two possible origins for the auriferous fluids; namely magmatic and metamorphic. The exploration target according to the magmatic model, is a late-Archaean, hydrothermally altered, mineralized and fractured granitic intrusion preferably with a granodioritic or quartz-dioritic composition. The exploration target according to the metamorphic replacement model is a granitic stock that has intruded a zone of crustal weakness such as a shear zone, active during the late Archaean. Alternatively, the granitic intrusion should be affected by regionally extensive late-Archaean shearing. It should be hydrothermally altered, deformed and mineralized. Five areas within the Pietersburg granite-greenstone terrane were selected for the 'Regional Area Selection' phase of exploration for Archaean granite/gneiss-hosted gold deposits; namely Roodepoort, Waterval, Ramagoep, Moletsie and Matlala. Roodepoort contains a known granodiorite-hosted gold deposit; the Knight's Pluton, and served as an orientation survey for this project. The use and interpretation of LANDSAT images formed an integral part of exploration techniques; to assess their usefulness in the exploration of Archaean granite/gneiss-hosted gold deposits. Area selection criteria for granite/gneiss-hosted gold mineralization at Roodepoort are the major ENE-trending shear zone, the NNW-trending lineament and hydrothermal alteration, shearing, quartz-stockworks and sulphide mineralization within the Knight's Pluton. The origin of the gold within the Knight's Pluton is uncertain; both magmatic and metamorphic models are possibilities. Ongoing exploration is in progress at Roodepoort. The only area selection criterion for granite/gneiss-hosted gold mineralization at Waterval is the sericitized, subcropping granites located within trenches. Gold mineralization is insignificant. No area selection criteria for Archaean granite/gneiss-hosted gold mineralization were located at Ramagoep, Matlala and Moletsie. No further exploration is recommended for all these areas. The MES image interpretations were successful in identifying lineaments, granitic outcrops, greenstones, vegetation and soil cover. The Clay-iron images adequately differentiated betweeen iron-rich and clay-bearing areas. However, not all clay-bearing areas were associated with hydrothermal alteratian; field checks were necessary to discriminate between weathered granites and hydrothermally altered granites. The Wallis images served to locally enhance the contrasts of the MES and Clay-iron images.
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Labarta, Charlie. "L'utilisation du granite dans les temples de Karnak." Thesis, Montpellier 3, 2014. http://www.theses.fr/2014MON30077.
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Dès le début de leur histoire, les Égyptiens ont réussi à maîtriser l'extraction et la taille du granite dans les carrières d'Assouan. Cette roche, réputée pour sa dureté, est particulièrement appréciée au Nouvel Empire où son exploitation prend une importance sans précédent. Les temples de Karnak, lieux de cultes majeurs à cette époque, constituent à ce titre les sites d'érection privilégiés de ces monuments en granite, à l'image des quinze obélisques qui furent, pendant un temps, dressés dans l'enceinte d'Amon. L'utilisation de ce matériau ne se limite cependant pas à ces monolithes ; il a également été employé pour de nombreux éléments d'architecture, de statuaire et de mobilier de culte.S'inscrivant dans une démarche pluridisciplinaire comprenant une approche égyptologique, géologique et technique, cet ouvrage propose une étude sur ces réalisations à travers le prisme du site de Karnak, suffisamment riche pour être, dans une certaine mesure, représentatif de l'utilisation générale du granite dans les temples de l'Égypte ancienneFrom the beginning of their history, the Egyptians have acquired an expert knowledge of granite quarrying and cutting in Aswan region. This stone, whose hardness made it famous, has been particularly used during the New Kingdom, when it got an unprecedented importance. The Karnak temples, as major cult spots at that time, have been a privileged site for the erection of monuments made from granite, as reflected by the fifteen obelisks which stood in the Amon enclosure for centuries. Its usage has not been limited to these large monolith pieces ; it has also been shaped in a tremendous amount of architectural elements, statues and objects for worship.Following an interdisciplinary approach combining an egyptological, a geological and a technical study, this work presents an investigation of granite monuments through the prism of the Karnak temples, whose history spreads far enough to be representative, in some way, of the general use of granite in ancient Egypt temples
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Shin, Jong Ho. "Numerical analysis of tunnelling in decomposed granite soil." Thesis, Imperial College London, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368048.
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Li, Qiuyi Bing. "Acoustic emissions in hydraulic fracturing of Barre granite." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/99581.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Civil and Environmental Engineering, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 147-148).
The purpose of this work is to observe acoustic emissions (AE) generated by laboratory scale hydraulic fracturing of Barre granite specimens with single or double flaw geometry. The scope of this work covers the experimental setup and subsequent analyses of these acoustic emissions, which in essence are elastic waves generated by displacements occurring within the rock specimen. Acoustic emissions can be analysed in a number of ways, whether individually or grouped together into events when a number of emissions arrive together. Individual emissions can be analysed for their amplitude, energy, or their frequency content while the source location and source mechanism can be inferred from events. The AE data are analysed in conjunction with water pressure, high resolution images, and high speed video taken during the experiment. Section 3 of this work outlines the selection and subsequent modification of the AE acquisition system with a specific focus on capturing AE at the end of each experiment in order to compare results to high speed video. This section describes the initial equipment selection, as well as initial experiments where it was noted that crucial data were missing around the time of the fracture event. This issue was largely resolved by modifying the system parameters as well as upgrading the PC supporting the AE acquisition cards. Section 4 of this work describes analysis of one experiment, providing an in-depth start-to-finish account of the nature of acoustic emissions at different phases of the experiment. This section also considers all of the hydraulic fracture experiments performed at different vertical loads and specimen flaw geometries, and draws some tentative conclusions regarding hydraulic fracturing in granite.
by Qiuyi Bing Li.
S.M.
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Dumont, Aaron. "Bodwell: King of the “Granite Ring” 1852-1922." Ohio University / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1089914885.
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Dumont, Aaron A. "Bodwell; king of the "Granite Ring" 1852-1922." Ohio : Ohio University, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1089914885.
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Shariati, Hossein. "Mechanical modeling of granite subjected to contact loading." Licentiate thesis, KTH, Hållfasthetslära (Avd.), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-263592.
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The mechanical properties of Bohus granite subjected to contact loading is investigated based on experimental and numerical results. An elasto-plastic constitutive material model combined with a damage description is employed. The material model parameters are determined based on experimental results. Any kind of inelastic deformation except the tensile failure is described by a linear Drucker-Prager (DP) plasticity model with variable dilation angle. As for the damage description, an anisotropic damage model (DFH model) is considered to account for the tensile failure (i.e. mode I fracture). The resulting constitutive model is implemented numerically to simulate the mechanical behavior of the material under indentation loading up to its load capacity. In paper A, the DP material model parameters are calibrated based on quasioedometric tests performed in an earlier work. It is described how the yield surface and dilation angle are determined from this test. The calibrated material model is implemented numerically in a commercial finite element software. The numerical model is validated based on quasi-static spherical indentation tests performed in this work. The force-penetration (P-h) response of the material is recorded during the indentation tests. Moreover, a high speed camera is utilized to observe the specimen surface around the contact area during the indentation test. It is detected that the observed load-drops in the P-h response correspond to material removals on the specimen surface. The tested specimens are also scanned by X-ray tomography to investigate the fracture pattern. In paper B, the anisotropic DFH damage model is employed in order to predict the fracture pattern observed in the indentation test. The chosen damage model considers the heterogeneity in the material tensile strength. It is described how the statistical distribution of the tensile strength is calibrated. The calibrated DFH model is combined with the DP model and the resulting DP-DFH model is utilized to simulate the P-h response and the fragmentation process of Bohus granite subjected to quasi-static contact loading.Examinator: Professor Mårten Olsson, KTH, Stockholm
QC 20191108
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Euzen, Tristan. "Pétrogenèse des granites de collision post-épaississement : le cas des granites crustaux et mantelliques du complexe de Pontivy-Rostrenen, Massif armoricain, France /." Rennes : Université de Rennes 1, Géosciences, 1993. http://catalogue.bnf.fr/ark:/12148/cb35606764q.
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Ramphaka, Priscilla L. "The origin of rhythmic magmatic layering in coarse-grained porphyritic S-type granite of the Peninsula pluton, Cape Granite Suite, South Africa." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85741.
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Thesis (MSc)--Stellenbosch University, 2013.ENGLISH ABSTRACT: Rhythmic magmatic layering in granites is an intriguing feature that has been reported from plutons with contrasting chemical compositions from a wide range of tectonic settings. Layered granites are rare and occur in association with volumetrically dominant non-layered rocks having similar composition. Understanding the origin of such layering in granites, particularly from well exposed outcrops, may give crucial insights on the physical-chemical conditions and processes (such as fractional crystallization, size and composition of individual magma batches, efficiency of mixing between batches etc.) within magma chambers during their construction. In the Cape Granite Suite, rhythmic layering is exceptionally well preserved in outcrops of the S-type granodioritic to monzogranitic Peninsula pluton along the coastline of the small town of Llandudno. At Llandudno, the granodioritic facies of the Peninsula pluton is exposed as a coarse-grained, cordierite and K-feldspar phenocrystic granite (referred to as Llandudno granodiorite in this study). Layering within the Llandudno granodiorite occurs within several lens-shaped bodies, of which the largest, with a thickness of about 5 m. The studied rhythmic sequence comprises 50 layers with thicknesses ranging between 5 and 50 cm. Each layer is typically characterised by a sharp lower contact overlain by a biotite-rich portion containing approximately 50 vol. % biotite. This mafic lower portion, grades upwards into a strongly leucocratic upper portion enriched in quartz, plagioclase and K-feldspar. The layered rocks host a substantially lower abundance of K-feldspar megacrysts and cordierite than the surrounding Llandudno granodiorite. In particular, cordierite crystals are five times less abundant in the layered zone than the un-layered Llandudno granodiorite. The K-Feldspars megacrysts that do occur within the layering are generally concentrated in the mafic part of some of the layers and are commonly oriented parallel to the layering. The K-feldspar megacrysts are significantly smaller than those in Llandudno granodiorite, but were found to be similar in composition. The whole rock compositions of the layered rocks are peraluminous with A/CNK >1.4. They have lower Mg#s (51 to 58) than the Llandudno granodiorite (51 to 65). The Na2O/CaO ratio of mafic and leucocratic portions is higher than in the Peninsula pluton. The mafic portions show an enrichment of trace and rare earth elements relative to the leucocratic portions and Peninsula pluton. The difference in bulk rock composition as well as trace and rare earth elements composition shows that the layered rocks were not formed by magmas produced by differentiation of the Llandudno granodiorite. The differences in biotite composition in basal sections of adjacent layers suggest that each layer represents a separate magma pulse, with the mafic portions of the layers largely representing an accumulation of the crystals in the magma batch at the time of injection and that these crystals mostly consist of orthopyroxene and biotite. This is in agreement with the findings based on the whole rock chemistry of the layers compared with the Llandudno granodiorite. The inclusion of K-feldspar megacrysts from the host granite into the layering, as well as the exceptional state of preservation of the layering, suggests that the layering formed relatively late in the crystallization sequence of the granite. This, in combination with the evidence for subtle differences in the chemistry of the magmas that formed separate layers, suggests that the layers represent a frozen feeder zone in the Peninsula pluton recording small successive pulses of magma addition. Frequent occurrence of the less-preserved layered biotite schlieren in the pluton may represent the equivalents of the layering that have become partially digested and texturally equilibrated with the host magma.
AFRIKAANSE OPSOMMING: Ritmiese magmatiese gelaagdheid in graniet is ’n interessante kenmerk van plutone met teenstellende chemiese samestellings in ’n wye verskeidenheid tektoniese omgewings. Gelaagde graniet is seldsaam en kom saam met volumetries dominante, niegelaagde gesteentes met soortgelyke samestellings voor. ’n Begrip van die oorsprong van hierdie gelaagdheid in graniet, veral in goed sigbare dagsome, kan belangrike insig verleen in die fisies-chemiese omstandighede en prosesse (soos fraksionele kristallisasie, die grootte en samestelling van individuele volumes magma, die doeltreffendheid van volume-vermenging, ensovoorts) in magmakamers gedurende die vorming daarvan. In die Kaapse granietgroep het ritmiese gelaagdheid besonder goed behoue gebly in dagsome van die S-tipe granodioritiese tot monsogranitiese Skiereilandse plutoon langs die kuslyn van die voorstad Llandudno. Die granodioritiese fasies van die Skiereilandse plutoon by Llandudno manifesteer in die vorm van ’n grofkorrelrige, kordiëritiese en K-veldspatiese fenokris-graniet (wat in hierdie studie Llandudno-granodioriet genoem word). Gelaagdheid in die Llandudno-granodioriet kom voor in verskeie lensvormige massas, waarvan die grootste sowat 5 m dik is. Die bestudeerde ritmiese opeenvolging bestaan uit 50 lae met diktes van tussen 5 cm en 50 cm. Elke laag word gekenmerk deur ’n skerp onderste kontakvlak wat bedek is met ’n biotiet-ryke gedeelte wat uit sowat 50 vol % biotiet bestaan. Hierdie mafiese onderste gedeelte gradeer opwaarts in ’n sterk leukokratiese boonste gedeelte wat ryk is aan kwarts, plagioklaas en K-veldspaat. Die gelaagde gesteentes bevat beduidend minder K-veldspatiese megakriste en kordiëriet as die omliggende Llandudno-granodioriet. Die kordiëritiese kristalle in besonder kom vyf keer minder in die gelaagde sone as in die niegelaagde Llandudno-granodioriet voor. Die K-veldspatiese megakriste wat wél in die gelaagdheid voorkom, is oor die algemeen in die mafiese gedeelte van sommige lae gekonsentreer, en is meestal parallel met die gelaagdheid georiënteerd. Die K-veldspatiese megakriste is aansienlik kleiner as dié in die Llandudno-granodioriet, maar het ’n soortgelyke samestelling. Die heelrots-samestellings van die gelaagde gesteentes is peralumineus, met A/CNK >1,4. Dit toon ook laer Mg#s (51 tot 58) as die Llandudno-granodioriet (51 tot 65). Die Na2O/CaO-verhouding van die mafiese en leukokratiese gedeeltes is hoër as in die Skiereilandse plutoon. In die mafiese gedeeltes is daar ‘n verryking in spoor- en skaarsaarde-elemente relatief tot die leukokratiese gedeeltes sowel as die Skiereilandse plutoon. Die verskil in heelrots-samestelling sowel as spoor- en seldsame-aardelementsamestelling toon dat die gelaagde gesteentes nié gevorm is deur magmas wat uit differensiasie van die Llandudno-granodioriet ontstaan het nie. Uit die verskille in die biotiet-samestelling van basissnitte uit aanliggende lae word afgelei dat elke laag ’n afsonderlike magmapuls verteenwoordig, terwyl die mafiese gedeeltes van die lae hoofsaaklik ‘n versameling van kristalle verteenwoordig wat tydens inplasing van die magma volume gevorm het, meestal ortopirokseen en biotiet. Dít stem ooreen met die bevindinge rakende die heelrots-chemie van die lae in vergelyking met die Llandudno-granodioriet. Die insluiting van K-veldspatiese megakriste vanaf die moedergraniet by die gelaagdheid, dui daarop dat die gelaagdheid betreklik laat in die kristallisasie-orde van die graniet gevorm het. Dít, tesame met bewyse van subtiele verskille in die chemie van die magmas waaruit afsonderlike lae gevorm is, dui daarop dat die lae ’n bevrore toevoersone in die Skiereilandse plutoon uitmaak wat kort, opeenvolgende pulse van magmatoevoeging vasgevang het. Die gereelde voorkoms van swakker bewaarde, gelaagde biotiet-sliere in die plutoon kan moontlik dui op sones van die gelaagdheid wat gedeeltelik verteer is en tekstureel met die moedermagma ge-ekwilbreer het.
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Yan, Wai Man. "Experimental study and constitutive modelling of re-compacted completely decomposed granite /." View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?CIVL%202003%20YAN.
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Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2003.Includes bibliographical references (leaves 168-177). Also available in electronic version. Access restricted to campus users.
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Awoleye, Olumuyiwa Adebayo. "Weathering and iron oxide mineralogy of Hong Kong granite." Thesis, University of Glasgow, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318702.
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Loh, Yu-Im 1977. "2-dimensional temperature modeling in Lower Granite Reservoir (Washington)." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/80963.
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Molyneux, Simon J. "Processes of granite emplacement : NW Ireland and SE Brazil." Thesis, Durham University, 1997. http://etheses.dur.ac.uk/4774/.
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This thesis is a study of some of the processes which operate at mid crustal levels (10- 20km) during the emplacement of granitoid magmas, with particular reference to the process of in-situ expansion and the association between magma emplacement and orogen evolution. A number of plutons were studied to assess this the Ardara pluton from Donegal, NW Ireland, together with the Atibaia, Morro Azul, Imbiricu and Itapeti plutons from the Rio Paraiba do Sul shear belt (RPSSB), Sao Paulo state, SE Brazil. The emplacement of the Ardara pluton has been the subject of studies by many authors since the 1950's. It has been interpreted as a diapir ascending along a thrust, a granite balloon which forcefully created more than 60% of its space and, most recently, as a set of nested diapirs which forcefully created only 30% of their own space. Field mapping together with the determination of finite strain within the pluton, shortening estimates, shear sense determinations, petrographic deformation fabrics and computer modelling indicates that: i) the pluton displays a concentrically increasing finite strain and it expanded in-situ from a central 'injection point', having possibly ascended along a shear zone-related conduit; ii) the country rocks partitioned intense strains into the 500m closest to the pluton, a deformation feature which is shown to be consistent with a power-law wallrock theology; Hi) earlier granite pulses and the country rock were 'shouldered aside' to the east and west, expansion of the pluton, which was preferentially in a northwards direction; iv) that the intrusion related shortening preserved within the wallrocks was approximately equivalent to the strain preserved within pluton and the space requirements for the pluton are essentially met by preserved forceful emplacement-related strains; and v) if the pluton magma is considered as having ascended through dyke-like conduits emplacement could occur in a minimum of ~4000yrs, whereas magma ascent as a Hot Stokes diapir would require hundreds of thousands to millions of years for complete emplacement. Finally, the Ardara pluton does not conform to any of the established criteria for diapir-like ascent of a magma body and the data demonstrate it to be a testable example of a pluton which expanded entirely in-situ. The Rio Paraiba do Sul shear belt (RPSSB) is a dextral transpressional segment of the Late Precambrian Brasiliano-Pan African orogenic belt. The studied plutons were emplaced in the latter stages of this orogen in close spatial association with one of the many northeast-southwest trending, sub-vertical, continental-scale shear zones. All the granites show a similar emplacement and deformation history despite their different petrographic features and isotopic ages. This history consists of an early shallowly dipping, low angle fabric, in the country rocks, associated with crustal thickening, the later development of dominantly dextral sub-vertical shear zones, followed by the emplacement of the studied plutons and finally overprinting by a pervasive dextral plane strain and late-stage discrete mylonitic shears. Field examination demonstrates that: i) each of the plutons preserves an internally homogeneous emplacement-related finite strain, weak magmatic fabric, magma sheets and weakly deformed wallrocks; ii) magmatic shear sense determinations and wallrock deformation fabrics indicate that, during emplacement, the RPSSB was extending (at least at the emplacement level) in an east-west direction creating sinistral dilatational pull-aparts along the major shear zones, into which granitic magma was preferentially emplaced; and Hi) within this generally extensional context there was a component of long axis perpendicular in-situ forceful expansion, this created no more than 20% of the width of any one granite. Applying a simple pull-apart extension model suggests that pluton emplacement was associated with approximately 40% regional extension sub-parallel to the former orogenic convergence direction. This emplacement, as a result of sheeting through dyke-like conduits, requires thousands of years, rather than the millions of years required for ascent and emplacement of a Hot Stokes diapir. Interpreting these results suggests that the intruded granitoids are associated with a mid-crustal component of orogen perpendicular extension I collapse during the latter stages of the Brasiliano orogeny. Such extension I collapse could have been initiated by: a cessation in continental convergence or; by the delamination of a thickened thermal boundary layer, a process which has been suggested to be the driving force behind orogenic collapse in younger orogenic belts. These examples demonstrate that: i) 'forceful' balloon-like emplacement of granitic magma can occur; ii) there are very close inter-relationships between granite emplacement and orogenic dynamics; and Hi) that 'space' for granitoid magma can be created by a combination of forceful and dilatational and fault-related mechanisms.
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Colas, Annie. "Flore et végétation de la côte de granite rose." Nantes, 1985. http://www.theses.fr/1985NANT366P.
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Krasner, Paul. "Strain Localization Mechanisms in the Scituate Granite, Rhode Island." University of Akron / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=akron1497285708350254.
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Tibbits, Tawny Lynn Bailey. "Geochemical sourcing of granite ground stone tools from Belize." Diss., University of Iowa, 2016. https://ir.uiowa.edu/etd/3202.
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Portable X-ray fluorescence (pXRF) provides a new alternative to destructive methods of raw material characterization, such as X-ray fluorescence (XRF), neutron activation analysis (NAA), and traditional thin section petrography, although its effectiveness on coarse-grained materials, such as granite, has been questioned. This project addressed this question by determining the effectiveness of pXRF in characterizing granites from Belize and in sourcing granite ground stone tools from Maya sites in Belize. Geochemical fingerprints were defined for three potential source areas (granite plutons in the Maya Mountains of Belize) using outcrop samples. Samples were analyzed using pXRF, XRF, electron microprobe (EMPA), and thin section analyses. PXRF data from archaeological collections of granite ground stone tools from sites in Belize were then compared to the pluton geochemical signatures.
There were two principle results of this research. First, analyses indicated that pXRF can accurately characterize the geochemistry of granites from Belize on a suite of elements. Second, this research demonstrated that the Maya of Belize exploited multiple granite outcrops and participated in different kinds of exchange networks to acquire granite, sometimes acquiring stone from the nearest outcrops and sometimes not. While Mountain Pine Ridge was the dominant source outcrop that was exploited, Cockscomb Basin and Hummingbird Ridge granites were also quarried or scavenged. Sometimes the closest source was used, as is the case at Alabama, who exploited the locally available Cockscomb Basin granite. Through this study it appears that the nearest pluton was not always used. Instead Mountain Pine Ridge granite tools were imported from a greater distance, implying that there were additional factors, such as economic partners and changing political powers, which lead to Mountain Pine Ridge granite being the most pervasive in most archaeological collections within Belize.
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Zhu, Ze-Ying. "Étude minéralogique des granites de métaux rares en Chine méridionale : étude de cas du granit de Songshugang et de Huangshan, province de Jiangxi." Thesis, Université de Lorraine, 2018. http://www.theses.fr/2018LORR0141.
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Les métaux rares, comme le niobium (Nb), le tantale (Ta), le tungstène (W) et l'étain (Sn), sont définis comme des «ressources stratégiques» ou des «matériaux critiques». Dans cette étude, nous prenons les gisements de Nb de Huangshan et de Ta de Songshugang dans le complexe de Lingshan, province de Jiangxi, en Chine du Sud, comme exemples. Les roches de ce gisement sont classées en deux catégories en fonction de la présence de micas riches en Nb et de la quantité de columbite-tantalites: granites à grain moyen avec des micas riches en Nb et sans columbite-tantalites, et granites à grain fin et pegmatites riches en columbite-tantalites. Ces columbite-tantalites sont riches en Nb et pauvres en Mn, les classant comme columbite. Ces columbites ont des zonations complexes liées à des processus répétitifs. Notre travail indique plutôt que la formation de tels minéraux est liée à des processus de mélanges multiples avec au moins deux types de magmas. Les granites à grain moyen dans la suite Huangshan sont différents des autres granites du complexe de Lingshan par la composition de leurs micas: Li-annite (granite MA) et "protolithionite" (granite MP). Ils sont caractérisés par des teneurs Nb élevées (moyenne de 144 ppm en MP et 158 ppm en MA) et des rapports Nb/Ta très élevés (moyenne 15,3 en MP et 31,2 en MA). Le niobium est principalement hébergé dans les micas, avec une teneur moyenne en Nb de 1347 ppm dans les Li annites, et 884 ppm dans le «protolithionite», concentrations encore jamais mesurées dans les micas d’origine magmatique. Avec un contenu estimé à ~80 kt Nb, les granites de Huangshan représentent un nouveau style potentiel de ressource de Nb. Le granite à albite de Songshugang est localisé dans l'ouest du complexe de Lingshan et est enrichi en Ta. Le granite de Songshugang n’affleure pas et est se trouve sous des couches de granites à feldspath K-topaze, de greisens et de pegmatite. Tous les granites et pegmatites sont fortement peralumineux. Les minéraux de columbite-tantalites, de zircons et de cassitérites sont constants pour chaque type de roches et présentent les mêmes textures bi-phasées. Les caractéristiques pétrographiques indiquent que le stade précoce de columbite et de zircon ont été formés dans un environnement strictement magmatique. Le stade postérieur de ces minéraux a été influencé par des circulations fluides à la transition magmatique-hydrothermale. Les micas montrent également une texture en deux étapes, avec une grande quantité de d’inclusions de columbite-tantalites. L'enrichissement en Rb dans les bordures (Znw-II) est le résultat d’un fractionnement magmatique, comme démontré par la diminution de la teneur en Nb (16,3-108 ppm comparé avec 109-313 ppm pour le coeur). Cependant, les teneurs faibles et invariables du Ta, W et Sn démontrent que le magma résiduel n'a eu aucune influence sur les processus post-magmatiques postérieurs, contrairement aux minéraux de columbite-tantalites. Enfin, les datations U-Pb in-situ sur zircons et columbite-tantalites démontrent que les granites de Huangshan et de Songshugang se sont mis en place vers 130 Ma durant l’épisode tardi-Yanshanien (Crétacé), au même moment que l’ensemble des roches magmatiques formant le complexe de Lingshan. Ce résultat indique que cette période géologique est d’intérêt pour la formation de ressources en Nb-Ta, définissant une nouvelle période géologique prospective pour ces ressourcesRare metals, including niobium (Nb), tantalum (Ta), tungsten (W) and tin (Sn), are defined as “strategic resources” or “critical materials”. For this work, we studied the Huangshan Nb deposit and Songshugang Ta deposit, in the Lingshan complex, Jiangxi Province, South China, as examples. The rocks from Huangshan granite are classified in two categories based on the occurrence of Nb-rich mica and the amount of columbite-tantalites minerals: medium-grained granites with Nb-rich mica and devoided of columbite-tantalites and fine-grained granites and pegmatites rich in columbite-tantalite minerals. Columbite-tantalite minerals are classified as columbite-(Fe), and characterized by complex zonings with various “go and back” processes, indicating that their formation is linked to multi-mixing processes of two different magma sources. The medium-grained granites in the Huangshan suite differed from the other granites of the Lingshan complex by their mica compositions: lithian annite (MA granite) and “protolithionite” (MP granite). They are characterized by elevated Nb contents (average 144 ppm in MP and 158 ppm in MA) and very high Nb/Ta ratios (average 15.3 in MP and 31.2 in MA). Niobium is mainly hosted in the micas, with an average Nb content of 1,347 ppm in the lithian annite, and 884 ppm in the “protolithionite”. Such contents are the highest ever reported in magmatic-related micas. With an estimated content of ~80 kt Nb, the Huangshan granites represent a new style of potential Nb resource. The Songshugang albite granite is found in the west of Lingshan complex and is specifically enriched in Ta. The major Songshugang albite granite is buried and covered by layers of K-feldspar granite, greisen and pegmatite. All the granites are strongly peraluminous. The compositions of columbite-tantalite minerals, the zircons and cassiterites are constant and display a similar two-stage texture. Petrographic features indicate that the early-stage columbite and zircon were formed in magmatic environment, whereas the later-stage of rare-element minerals were influenced by fluid fluxes at the magmatic-hydrothermal transitional stage. Micas also show a two-stage texture. The Rb-enrichment in the margin of the zinnwaldite is the result of magmatic fractionation, as also demonstrated by the decrease of Nb contents (16.3-108 ppm compare with core of 109-313 ppm). The invariable low contents of Ta, W and Sn demonstrate that the residual melt has no influence on later post-magmatic stages, contrary to the columbite minerals. Finally, in-situ U-Pb dating of zircon and columbite-tantalite by SIMS and LA-ICP-MS indicates that both Huangshan and Songshugang granites were emplaced at ca. 130 Ma during Later Yanshanian (or Cretaceous) and contemporary with the formation of the Lingshan complex. This result indicates that the Later Yanshanian is a prospective geological period for Nb-Ta deposits, and this result enlarges the time frame of rare-metal mineralization
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Zhu, Ze-Ying. "Étude minéralogique des granites de métaux rares en Chine méridionale : étude de cas du granit de Songshugang et de Huangshan, province de Jiangxi." Electronic Thesis or Diss., Université de Lorraine, 2018. http://www.theses.fr/2018LORR0141.
Full textAbstract:
Les métaux rares, comme le niobium (Nb), le tantale (Ta), le tungstène (W) et l'étain (Sn), sont définis comme des «ressources stratégiques» ou des «matériaux critiques». Dans cette étude, nous prenons les gisements de Nb de Huangshan et de Ta de Songshugang dans le complexe de Lingshan, province de Jiangxi, en Chine du Sud, comme exemples. Les roches de ce gisement sont classées en deux catégories en fonction de la présence de micas riches en Nb et de la quantité de columbite-tantalites: granites à grain moyen avec des micas riches en Nb et sans columbite-tantalites, et granites à grain fin et pegmatites riches en columbite-tantalites. Ces columbite-tantalites sont riches en Nb et pauvres en Mn, les classant comme columbite. Ces columbites ont des zonations complexes liées à des processus répétitifs. Notre travail indique plutôt que la formation de tels minéraux est liée à des processus de mélanges multiples avec au moins deux types de magmas. Les granites à grain moyen dans la suite Huangshan sont différents des autres granites du complexe de Lingshan par la composition de leurs micas: Li-annite (granite MA) et "protolithionite" (granite MP). Ils sont caractérisés par des teneurs Nb élevées (moyenne de 144 ppm en MP et 158 ppm en MA) et des rapports Nb/Ta très élevés (moyenne 15,3 en MP et 31,2 en MA). Le niobium est principalement hébergé dans les micas, avec une teneur moyenne en Nb de 1347 ppm dans les Li annites, et 884 ppm dans le «protolithionite», concentrations encore jamais mesurées dans les micas d’origine magmatique. Avec un contenu estimé à ~80 kt Nb, les granites de Huangshan représentent un nouveau style potentiel de ressource de Nb. Le granite à albite de Songshugang est localisé dans l'ouest du complexe de Lingshan et est enrichi en Ta. Le granite de Songshugang n’affleure pas et est se trouve sous des couches de granites à feldspath K-topaze, de greisens et de pegmatite. Tous les granites et pegmatites sont fortement peralumineux. Les minéraux de columbite-tantalites, de zircons et de cassitérites sont constants pour chaque type de roches et présentent les mêmes textures bi-phasées. Les caractéristiques pétrographiques indiquent que le stade précoce de columbite et de zircon ont été formés dans un environnement strictement magmatique. Le stade postérieur de ces minéraux a été influencé par des circulations fluides à la transition magmatique-hydrothermale. Les micas montrent également une texture en deux étapes, avec une grande quantité de d’inclusions de columbite-tantalites. L'enrichissement en Rb dans les bordures (Znw-II) est le résultat d’un fractionnement magmatique, comme démontré par la diminution de la teneur en Nb (16,3-108 ppm comparé avec 109-313 ppm pour le coeur). Cependant, les teneurs faibles et invariables du Ta, W et Sn démontrent que le magma résiduel n'a eu aucune influence sur les processus post-magmatiques postérieurs, contrairement aux minéraux de columbite-tantalites. Enfin, les datations U-Pb in-situ sur zircons et columbite-tantalites démontrent que les granites de Huangshan et de Songshugang se sont mis en place vers 130 Ma durant l’épisode tardi-Yanshanien (Crétacé), au même moment que l’ensemble des roches magmatiques formant le complexe de Lingshan. Ce résultat indique que cette période géologique est d’intérêt pour la formation de ressources en Nb-Ta, définissant une nouvelle période géologique prospective pour ces ressourcesRare metals, including niobium (Nb), tantalum (Ta), tungsten (W) and tin (Sn), are defined as “strategic resources” or “critical materials”. For this work, we studied the Huangshan Nb deposit and Songshugang Ta deposit, in the Lingshan complex, Jiangxi Province, South China, as examples. The rocks from Huangshan granite are classified in two categories based on the occurrence of Nb-rich mica and the amount of columbite-tantalites minerals: medium-grained granites with Nb-rich mica and devoided of columbite-tantalites and fine-grained granites and pegmatites rich in columbite-tantalite minerals. Columbite-tantalite minerals are classified as columbite-(Fe), and characterized by complex zonings with various “go and back” processes, indicating that their formation is linked to multi-mixing processes of two different magma sources. The medium-grained granites in the Huangshan suite differed from the other granites of the Lingshan complex by their mica compositions: lithian annite (MA granite) and “protolithionite” (MP granite). They are characterized by elevated Nb contents (average 144 ppm in MP and 158 ppm in MA) and very high Nb/Ta ratios (average 15.3 in MP and 31.2 in MA). Niobium is mainly hosted in the micas, with an average Nb content of 1,347 ppm in the lithian annite, and 884 ppm in the “protolithionite”. Such contents are the highest ever reported in magmatic-related micas. With an estimated content of ~80 kt Nb, the Huangshan granites represent a new style of potential Nb resource. The Songshugang albite granite is found in the west of Lingshan complex and is specifically enriched in Ta. The major Songshugang albite granite is buried and covered by layers of K-feldspar granite, greisen and pegmatite. All the granites are strongly peraluminous. The compositions of columbite-tantalite minerals, the zircons and cassiterites are constant and display a similar two-stage texture. Petrographic features indicate that the early-stage columbite and zircon were formed in magmatic environment, whereas the later-stage of rare-element minerals were influenced by fluid fluxes at the magmatic-hydrothermal transitional stage. Micas also show a two-stage texture. The Rb-enrichment in the margin of the zinnwaldite is the result of magmatic fractionation, as also demonstrated by the decrease of Nb contents (16.3-108 ppm compare with core of 109-313 ppm). The invariable low contents of Ta, W and Sn demonstrate that the residual melt has no influence on later post-magmatic stages, contrary to the columbite minerals. Finally, in-situ U-Pb dating of zircon and columbite-tantalite by SIMS and LA-ICP-MS indicates that both Huangshan and Songshugang granites were emplaced at ca. 130 Ma during Later Yanshanian (or Cretaceous) and contemporary with the formation of the Lingshan complex. This result indicates that the Later Yanshanian is a prospective geological period for Nb-Ta deposits, and this result enlarges the time frame of rare-metal mineralization
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Masmejean, Bruno. "Le complexe granito-anatectique sombre du Vivarais et les granites intrusifs associés : pétrologie et signification géodynamique." Lyon 1, 1987. http://www.theses.fr/1987LYO10131.
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L'etablissement d'une carte a 1/25 000 de la region de st felicien et d'une synthese a 1/100 000 du vivarais permet de cerner les importances respectives et les relations des diverses formations sombres affleurant dans la partie orientale du vivarais. L'etude petrographique et geochimique de chacune d'entre elles conduit a la determination de leur origine et de leur histoire
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To, Chiu-yin. "A unified elasto-plastic model for saturated loosely compacted completely decomposed granite." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/b40203554.
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SILVA, Mickey Anderson Paixão da. "Influência das características morfológicas de britas graníticas e gnaíssicas na resistência à compressão do concreto." Universidade Federal de Pernambuco, 2016. https://repositorio.ufpe.br/handle/123456789/18425.
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Em virtude dos agregados constituírem os recursos minerais mais acessíveis e também serem responsáveis por uma enorme parcela do material consumido na construção civil, faz-se necessário um estudo mais aprofundado a respeito da utilização e aplicação dessa matéria prima. O objetivo principal é qualificar a relação entre os resultados de resistências à compressão do concreto, obtidos por meio de testes feitos em corpos-de-prova moldados com diferentes tipos de brita, de modo a identificar aquela que proporciona uma maior resistência no mesmo, quando submetido aos esforços uniaxiais de compressão. Para isso foram escolhidas amostras de rochas, sendo três granitos e três gnaisses para análise da qualidade do concreto produzido a partir das respectivas britas. As britas foram analisadas macroscopicamente e todas as amostras foram submetidas às mesmas etapas de britagem, e posteriormente o material resultante dessa etapa passou pelo peneirador mecânico. Através desse processo, avaliou-se individualmente o índice de forma, o módulo de finura e o percentual dos minerais com clivagem dos devidos tipos de rochas afim de entender melhor o motivo dos posteriores resultados do comportamento do concreto com relação à trabalhabilidade e resistência a compressão uniaxial para cada um dos tipos de brita. A escolha do tipo de cimento torna-se muito relevante para esta análise. Faz-se necessário a escolha de um cimento que dê margem para que o tipo de brita seja a variável mais importante e decisiva no processo de resistência. Observa-se também que o índice de forma está relacionado ao percentual de minerais presentes na rocha que apresentam planos de clivagem. O valor do índice de forma está diretamente relacionado aos teores de minerais com um ou mais planos de clivagem contidos em cada amostra. Por fim, ficou constatado que o concreto que apresentou a maior resistência à compressão foi confeccionado por agregados com os menores módulos de finura; já os agregados com o maior módulo de finura resultaram num dos concretos menos resistentes.
Because the aggregate constitute the most accessible mineral resources and also account for a huge portion of the consumed in construction material, it is necessary to further study regarding the use and application of this raw material. The main goal is to qualify the relationship between the results of resistance to the concrete compressive obtained by means of tests made on specimens test pieces molded with different types of gravel, in order to identify one that provides greater strength in that when subjected to uniaxial compression efforts. For this rock samples were selected: three and three granite gneiss for analysis of the quality of concrete produced from the respective gravel. The gravel was analyzed macroscopically and all samples were subjected to the same steps of crushing, and then the resulting material has passed this stage by mechanical sieving. Through this process, we assessed individually the form of an index, the fineness modulus and percentage of minerals with cleavage of proper rock types in order to better understand the reason for the subsequent behavior of concrete results regarding the workability and compressive strength uniaxial for each type of grit. The choice of the type of cement becomes very relevant to this analysis. It is necessary to choose a cement margin so that the type of grit is most important and crucial variable in resistance process. It is also observed that the form of an index is related to the percentage of minerals present in the rock show cleavage planes. The value of the medium index is directly related to mineral contents in one or more cleavage planes contained in each sample. Finally, it was found that the concrete with the highest compressive strength was made by households with the lowest fineness modules; since aggregates with higher fineness modulus resulted in the least resistant concrete.
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Henrique-Pinto, Renato. "Metaconglomerados e rochas associadas do Grupo São Roque a noroeste da cidade de São Paulo: proveniência e implicações para a idade da sedimentação." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/44/44143/tde-11112008-115527/.
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O Grupo São Roque caracteriza-se por rochas de baixo grau metamórfico, depositadas em ambiente marinho com atividade vulcânica submarina. As ocorrências da Formação Morro Doce são dominadas por metarcóseos e metarenitos feldspáticos com expressivas lentes metaconglomeráticas, que formam uma seqüência considerada como unidade basal do Grupo São Roque. Os metaconglomerados, com o amplo predomínio de clastos graníticos, têm excelente potencial para identificação de suas fontes e idades. Rochas metavulcânicas ácidas e básicas intercaladas nesta seqüência constituem importante marcador tectônico e cronológico. O estudo petrográfico dos clastos graníticos dos metaconglomerados da Formação Morro Doce permitiu a identificação de quatro variedades petrográficas: biotita monzogranito porfirítico, biotita monzogranito inequigranular, biotita monzogranito equigranular e leucogranito inequigranular. O caráter comagmático entre os clastos é confirmado pelos dados petrográficos e geoquímicos. Rochas metavulcânicas ácidas que ocorrem intercaladas a metarcóseos e metaconglomerados, na região do Morro do Polvilho, correspondem a meta-traquidacitos e metariolitos porfiríticos. Os metarcóseos mostram afinidades geoquímicas com os clastos de granito dos metaconglomerados, e diferenciam-se das rochas metavulcânicas ácidas associadas pela geoquímica e pela petrotrama sedimentar composta predominantemente por feldspatos detríticos sub-angulosos. De características geoquímicas típicas de magmatismo intraplaca, em especial baixo mg# (~20), altos teores de Zr (560-730 ppm), Y e Nb, além de baixo Sr (70-120 ppm), as rochas metavulcânicas ácidas do Grupo São Roque apresentam similaridades com as metavulcânicas ácidas da base do Supergrupo Espinhaço. Datações U-Pb por LA-MC-ICP-MS em cristais de zircão extraídos das variedades predominantes de seixos graníticos revelaram idades Paleoproterozóicas (2199 ± 8.5 Ma e 2247 ± 13 Ma). Idades comparáveis só são encontradas regionalmente em núcleos do embasamento do Supergrupo Espinhaço (Complexo Mantiqueira) e Açungui (núcleos Tigre, Setuva e Betari). A idade de deposição dos metaconglomerados (1.75-1.79 Ga), indicada pelas datações U-Pb em rochas metavulcânicas intercaladas é consistente com a idade dos clastos (granito fonte), datados em 2.2 Ga, e com a ausência de indicações de contribuições de áreas-fontes mais jovens para os metassedimentos da Fm. Morro Doce.The São Roque Group is composed of low-grade metamorphic rocks deposited in marine environment with coeval volcanic activity. The Morro Doce Formation is dominated by metaarkose and feldspatic meta-sandstone with expressive metaconglomeratic lenses, which form a sequence regarded as the basal unit of São Roque Group. The metaconglomerates with wide prevalence of granite pebbles have excellent potential to identify their sources and ages. Metavolcanic acidic and basic rocks interspersed in this sequence are an important tectonic and geochronologic marker. The petrographic study of the granite pebbles from the Morro Doce Formation metaconglomerates allowed the identification of four petrographic varieties: porphyritic biotite monzogranite, inequigranular biotite monzogranite, equigranular biotite monzogranite and inequigranular leucogranite. The comagmatic character of these pebbles is confirmed by petrographic and geochemical data. Acid metavolcanic rocks interlayered with meta-arkose and metaconglomerates in the Morro do Polvilho region correspond to trachydacite and porphyritic meta-rhyolite. The metaarkose shows geochemical affinities with metaconglomerate granitic pebbles, and differs from the acid metavolcanic rocks both in their geochemical signature and in its sedimentary fabrics defined by the predominance of detritic subangulous feldspars. Their geochemical characteristics are typical of within-plate magmatism, especially the low mg # (~ 20), high Zr (560-730 ppm), Y, Nb, and low Sr (70-120 ppm), and is similar to the acid metavolcanics from the on Espinhaço Supergroup. U-Pb dating by LA-MC-ICP-MS in zircon crystals from the predominant varieties of granitic pebbles revealed Paleoproterozoic ages (2199 ± 8.5 Ma Ma and 2247 ± 13) for the main granitic source of the metaconglomerates. Comparable ages are found in the nuclei of Espinhaço Supergrup basament (Mantiqueira Complex) and Açungui (Tigre, Setuva and Betari nuclei). The depositional age of the metaconglomerates (1.75-1.79 Ga), indicated by U-Pb dating of interlayered metavolcanic rocks, is consistent with the age of the granitic source, (~2.2 Ga), and with the lack of signals of contribution from younger source areas for the Morro Doce Fm metasediments.
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Yang, Wenjin. "Géochimie et minéralogie des granites de la région de Hetai, province de Guangdong, Chine méridionale = Geochemistry and mineralogy of granites in the Hetai area, Guangdong, South China /." Thèse, Chicoutimi : Université du Québec à Chicoutimi, 1993. http://theses.uqac.ca.
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Thèse (D.R.Min.)-- Université du Québec à Chicoutimi, 1993.Thèse presentee en collaboration de l'Université du Quebec à Chicoutimi et Institute of geochemistry, Academia Sinica, China. CaQCU Document électronique également accessible en format PDF. CaQCU
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Foster, Pedro Luiz Luppi [UNESP]. "Geologia e petrologia do Maciço Palanqueta, Mina Bom Futuro, Rondônia." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/144675.
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Topázio granitos são rochas ácidas ultrafracionadas que ocorrem sob a forma de stocks, cúpolas ou diques em suítes graníticas pós-orogênicas ou anarogênicas, e são caracterizadas por seu enriquecimento extremo em flúor, associação com elementos litófilos e relação direta com muitos depósitos primários de metais raros (ex. Sn, W, Ta e Nb) encontrados pelo mundo. A mina Bom Futuro localiza-se no município de Ariquemes, região centro-norte de Rondônia, e é umas das maiores produtoras de estanho do país e congrega dois morros contíguos denominados Bom Futuro e Palanqueta, este último sendo o representante em superfície do Maciço Palanqueta. No Maciço Palanqueta são reconhecidas 5 fácies graníticas, sendo 4 delas topázio granitos: biotita-álcali-feldspato-granito equigranular, topázio-zinnwaldita-álcali-feldspato-granito equigranular, topázio-zinnwaldita-álcali-feldspato-granito porfirítico, topázio-zinnwaldita-álcali-feldspato-granito pórfiro e topázio-zinnwaldita-álcali-feldspato-granito miarolítico, além de diques de aplito, veios de pegmatito e veios e pipes de greisen mineralizados em cassiterita. Os veios pegmatíticos encontram-se cortando os diques de aplito e estes as demais fácies graníticas. As relações de contato entre as fácies graníticas é brusca, mas só é identificada relação de idade entre as fácies topázio-zinnwaldita-álcali-feldspato-granito porfirítico e topázio-zinnwaldita-álcali-feldspato-granito pórfiro. As características de campo, petrográficas e geoquímicas do Maciço Palanqueta permitem classifica-lo como um maciço granítico multifásico, intraplaca, tipo A e integrante peraluminoso da Suíte Granitos Últimos de Rondônia. Apesar de cronologicamente correlatos a seguinte ordem para a colocação das fácies graníticas é proposta: biotita-álcali-feldspato-granito equigranular topázio-zinnwaldita-álcali-feldspato-granito equigranular topázio-zinnwaldita-álcali-feldspato-granito porfirítico topázio-zinnwaldita-álcali-feldspato-granito miarolítico topázio-zinnwaldita-álcali-feldspato-granito pórfiro. O Maciço Palanqueta ainda não possui seus limites físicos definidos, bem como sua variação faciológica em seção, o que implica na possibilidade de potencial metalogenético em profundidade, em acordo com outros exemplos de topázio granitos encontrados na literatura.
Topaz granites are acidic ultrafracionated rocks that occur in the form of stocks, domes or dykes in granitic post-orogenic or anarogenic suites, and are characterized by their extreme enrichment in fluorine, association with lithophile elements and direct relationship with many primary deposits of rare metals (eg. Sn, W, Ta and Nb) found around the world. The Bom Futuro mine is located in the county of Ariquemes, north-central region of Rondonia State, and is one of the largest tin producer in the country and brings together two adjacent hills called Bom Futuro and Palanqueta, the last one being the representative surface of the Palanqueta massif. At the Palanqueta massif are recognized 5 granitic facies, 4 of them of topaz granites: equigranular biotite-alkali-feldspar granite, equigranular topaz-zinnwaldita-alkali-feldspar granite, porphyritic topaz-zinnwaldita-alkali-feldspar granite, porphyry topaz-zinnwaldita- alkali-feldspar granite and miarolitic topaz-zinnwaldita-alkali-feldspar granite, and aplite dikes, pegmatitic veins and veins and pipes of greisen mineralized in cassiterite. The pegmatite veins are cutting the aplite dykes and these all the other granitic facies. The contact relationships between the granitic facies is abrupt, but age relationship are only identified between the porphyritic topaz-zinnwaldita-alkali-feldspar granite and porphyry topaz-zinnwaldita-alkali-feldspar granite facies. The field, petrographic and geochemical data of Palanqueta massif allow classifies it as a within plate, A type, peraluminous. multifacies granitic massif, and member of the Younger Granites of Rondonia Suite. Although chronologically related the following order for placement of the granitic facies is proposed: biotite alkali-feldspar granite equigranular topaz-zinnwaldita-alkali-feldspar granite equigranular topaz-zinnwaldita-alkali-feldspar granite porphyry topaz-zinnwaldita -álcali-feldspar granite miarolítico topaz-zinnwaldita-alkali-feldspar granite porphyry. The Palanqueta massif does not have its physical boundaries defined, as well as their facies variation in vertical section, which implies the possibility of depth metallogenic potential, in accordance with other examples of topaz granites found in the literature.
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REJEB, AMEL. "Comportement thermomecanique du granite. Application au stockage des dechets radioactifs." Paris, ENMP, 1992. http://www.theses.fr/1992ENMP0357.
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L'enfouissement des dechets radioactifs en formation geologique profonde produira une elevation de temperature susceptible d'entrainer d'importantes modifications dans le milieu envisage. Cette these porte sur le stockage dans le granite et presente une etude du comportement thermomecanique basee sur les resultats de l'experience in situ thermo-hydro-mecanique de fanay-augeres. Des modelisations bidimensionnelle et tridimensionnelle ont permis de rendre compte, d'une maniere satisfaisante, de l'ensemble des observations faites in situ. La base de donnees experimentales issues de l'experience thm a permis de juger de la validite des nouveaux outils numeriques, construits en trois dimensions et utilisant la methode des elements finis. Ces codes de calcul pourront servir ulterieurement a simuler des cas de site de stockage reel
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Dubois, Isabelle E. "Specific surface area of some minerals commonly found in granite." Licentiate thesis, KTH, Industriell ekologi, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-41259.
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The specific surface area, determined by the BET method, is a parameter often used to scale results of mineral studies of surface reactions in terms of rate and capacity to the field scale. Such extrapolations of results from small-scale laboratory experiments to the field-scale are important within many environmental applications. An example of this is for the prediction of radionuclide retention in the bedrock surrounding a deep repository for radioactive waste, following failure of the engineered barriers, where radionuclides may sorb onto minerals constituting the geological environment. As a first step, the approach used in this work is to study the relationship between specific surface area and the particle size (0.075-8 mm) and to approach the field scale via measurements on large, centimetre-sized pieces, for seven natural minerals commonly found in granite: apatite, biotite, chlorite, K-feldspar, hornblende, labradorite and magnetite. The underlying assumption is that sorption of radionuclides can be related to specific surface area of a particular mineral in a continuation of this project.The results show that the phyllosilicates biotite and chlorite have a specific surface area that is about 10 times larger than the other minerals. Over the range of particle size fractions studied, the specific surface area varies between 0.1 and 1.2 m2g-1 for biotite and chlorite. The other studied minerals have specific surface areas varying between 0.01 m2g-1 for the largest fraction and up to 0.06 - 0.12 m2g-1 for the smallest. Results show linear relationships between the specific surface area and the inverse of the particle size for all studied minerals for small particle sizes, as expected. For some minerals, however, the data seemingly can be divided in two linear trends, where a change in internal surface area, surface roughness and/or particle geometry as the particle size decreases may explain this behaviour. Interestingly, for larger particles, there is a deviation from the linearity observed for small particles. Tentatively, this behaviour is attributed to a disturbed zone, created by the mechanical treatment of the material during particle size reduction, extending throughout small particles, but not altering an undisturbed core of the larger particles. In agreement with this, measurements on large pieces show a surface area 5 to 150 times lower than expected from the linear trends observed for the crushed material, implying an overestimation of the surface area and possibly also of the sorption capacities of the rock material from simple extrapolations of experimental results employing finely crushed material to the field situation.QC 20110929
Äspö Radionuclide sorption
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Lewis, Andrew M. "A gravity and magnetic investigation of the Monarto granite, S.A /." Title page, abstract and contents only, 1985. http://web4.library.adelaide.edu.au/theses/09SB/09sbl673.pdf.
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Toouli, Sarah Julia. "Sustainable management of the fairy penguin colony at Granite Island /." Title page, contents and abstract only, 2001. http://web4.library.adelaide.edu.au/theses/09AEVH/09aevht672.pdf.
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Bammeke, B. O. "Geochemical prospecting in a greenstone-granite complex, South West Nigeria." Thesis, Swansea University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.636029.
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A low-density reconnaissance geochemical survey was made of the stream sediments and rocks in the Akaka/Ago-Iwoye, Egbe and Igbo-Ora districts of the southwestern basement complex, Nigeria. The areas are underlain by mainly Precambrian greenstone rocks in close association with granites, gneisses, metasediments (quartzites, quartz-mica schists) and pegmatites. Typical rain forest areas and streams are dissected by a closely and deeply developed dentritic-subdentritic drainage pattern. This study compares the three areas and includes recommendations for further prospecting. Field and mineralogical petrological evidence indicates sulphide mineralization, and geochemical trends in the amphibolites favour a tholeiitic affinity with ultrabasic igneous proliths overprinted by post-magmatic processes. The range of concentrations and geochemical characteristics of elements commonly found in rocks and sediments are reviewed. More than 350 samples were collected and analysed for 17 trace and 10 major elements by X-ray fluorescence, atomic absorption and inductively coupled plasma emission spectroscopy. Analytical precision was monitored using duplicates, standards and reference materials and the statistical basis of analytical quality control examined. Computer based univariate and multivariate statistical techniques are applied to the geochemical data. Initial univariate analyses clearly establish anomalous elemental abundances. Anomalously high Mo, significant Ni and Au values are characteristic of the areas investigated. Particular geochemical patterns of single-element distribution were found. In general, multi-element associations in the sediments were similar to those discerned in the associated bed-rocks. The application of multiple regression analysis to sediments from the Egbe area revealed enhanced Cu and Ni anomalous populations which were suppressed by iron-oxide coprecipitation. R-mode analysis identified models meaningful in terms of correlation either with underlying parent rock, secondary processes of the surifical environment and mineralization. However, there are no clearly defined indications of the ore potential of the Akaka area. The fourth-factor (Au-Sr) for rock samples in the Igbo-Ora complex confirms occurrence of gold mineralization. A clear-cut association of rare-earths are shown in all the areas. The most significant findings of the present work were the identification of exploration target areas worth further investigations. Other aspects highlighted were the possibility of reliable indicator elements for ore mineralization in these areas, significant anomalies being evident in the rocks and sediments.
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Kane, Heather L. "Backgound controls on the weathering of granite in polluted environments." Thesis, Queen's University Belfast, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301719.
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Mdyusoff, Zainuddin. "Feldspar dissolution during the weathering of granite under tropical conditions." Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/11854.
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Much of Malaysia is composed of granite. Samples ranging from unweathered granite to surface soils from newly exposed cut slopes and drill-holes were analysed using Quantitative X-ray Powder Diffraction (QXRPD), X-ray Fluorescence spectrometry (XRF), Inductively-coupled plasma mass spectrometry (ICP-MS), Scanning Electron Microscopy (SEM) and Optical microscopy. Samples were also sent to commercial laboratories for the determination of geotechnical engineering index and strength properties. The analyses have brought about a categorization of the weathering profiles into 4 ‘zones’: top soil, saprolite, weathering boundary and unweathered granite zones. The reactions within the active weathering boundary zone dictate the formation of secondary minerals. The findings in each different zone have enlightened the understanding of the development of secondary minerals especially clays in a deep weathering profile. The study also confirms and furthers understanding of the way chemical weathering occurs on the K-feldspar grains and is followed by the mechanical collapse of the grains leading to the reduction in the geotechnical strength of the material. The major element mobility study did not show any relation to the degree of weathering within the saprolite. Trace element study did not give conclusive results. However, a rare earth element (REE) study shows that the mobility of REE depends on the degree of weathering. The presence of clay minerals and feldspar grains are related to the geotechnical engineering properties, especially the strength properties which are responsible to the stability of slopes.
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Oak, Keith Alan. "The geology and geochemistry of Closepet granite, Karnataka, South India." Thesis, Oxford Brookes University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278897.
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The Archaean craton of southern India has four main components. The multi-phase Peninsular gneiss, with ages from 3360-2900 Ma, is spatially dominant and grades from granulite facies in the south to greenschist facies in the north. Ages for the Peninsular gneiss range from 3360-2900 Ma. Within the craton are two suites of Greenstone Belts and supracrustal rocks. The older, high-grade Sargur type occur as enclaves in the Peninsular gneiss and are in places older than 3360 Ma. The younger, lower-grade type occur occasionally have unconformable bases with the Peninsular gneiss and have been dated from 3100-2605 Ma. Granitoids form the last major component with the Closepet granite being the largest, ages for the emplacement of the Closepet granite and many of the other granitoids cluster around 2500 Ma. The Closepet granite outcrops from Kabbal Durge in the south to the Deccan Plateau in the north, a distance of some 450 km. A 320 km section from Kabbal Durga to Hospet in the north exposes a linear trending granite. The granite outcrop varies from one of essentially partial melting and melt extraction in the south to a zone of melt accumulation in the central zone to a zone of high level intrusion of large granite bodies. Related to these changes in primary processes are changes in the granite phases, size, shape and intrusive style. The petrography of the granite phases is described. These studies help to constrain phase relationships. The petrography also provides evidence to suggest that the K-feldspar megacrysts are in fact phenocrysts. Analyses of major and trace elements utilised standard X.R.F. methods. However, the analyses of REE on selected samples involved the setting up of the department's "ICP for routine operation. This procedure is outlined. The geochemistry of the granite's is described melting and crystallization models being used to explain their petrogenesis. Harker diagrams indicate that plagioclase, sphene and apatite have strong controls on major element composition and that biotite was a residual or fractionating phase. The removal of restite biotite as granite magmas intrude is thought to be a significant process.Evidence from the petrography agrees with the equilibrium phase diagram at PH2 0 ~ 5 kbar. Plots of Peninsular gneiss in the granite phase diagram have a range of compositions which could provide minimum and non-minimum melts capable of producing the Closepet granite trend. Predicted fractional crystallization would produce a sequence of magma compositions comparable to those of the Closepet granite with an order of phase crystallization that agrees with petrographic evidence. The phase relationships further constrain subsequent melting and crystallization models utilising trace elements and REE.
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Neighbour, Matthew W. "Tantalum and niobium mineralogy and recovery from kaolinised Cornish granite." Thesis, University of Exeter, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.548619.
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The china clay industry in the UK produces vast quantities of benign waste through the production of clay and aggregate products. These wastes contain a wide array of minor quantities of accessory minerals, none of which have been quantitatively studied or properly classified in detail. In view of the potential for recovering rare elements, this project investigates the presence of these accessory minerals with particular focus on the tantalum and niobium ore mineral series, columbite-tantalite. Although these minerals are already known to be present, no research on their distribution within the potential ore body has been undertaken and knowledge of the structure of these and other tantalum minerals present is very limited. The thesis sets out to assess the potential resources available through analysis and interpretation of samples collected from Goonvean Ltd. SW England. Initial samples were taken from five operating pit faces to confirm the presence of tantalum mineralogy across the three areas worked by Goonvean Ltd (Goonvean, Rostowrack and Trelavour Downs's pits) for clay extraction. Detailed information of the elemental and mineralogical differences between these areas was gathered, using a variety of analytical techniques. To determine which single site had the most potential for concentrating tantalum efficiently. Based on element abundance, mineralogical content and characteristics of ore grains to upgrade, (Le. grain size, density and liberation) material from Trelavour Downs pit was selected for investigation. Drill core samples were collected and elemental distribution analysed, including Ta, Nb, Sn, Wand other trace level elements. Using geostatistical techniques the presence of trends or patterns within the area, which can give an insight into the mineralization, was investigated. This information was used to generate an estimate of grade and tonnages available. Although literature reports the presence of tantalum and niobium within the area, only one paper investigates the mineralogy from concentrates, (Scott et al. 1998) which from a small number of grains of columbite-tantalite showed a high variation in chemistry; Manning and Hill (1990) also recorded traces of the niobium and tantalum containing mineral ilmenorutile. In this study, QEMSCAN is applied to measure thousands of grains instead of tens of grains, providing improved detail into the mineralogical variability. The drill core samples were combined into composite samples which respect the geology. This produced eighteen samples which were analysed in full detail utilising mineral processing coupled with analytical techniques. Through this analysis, the tantalum minerals were classified, and other mineral species previously undiscovered in the area were identified. Notably QEMSCAN analyses enabled identification of the minerals present, including the gangue mineralogy and their characteristics. Laboratoryscale tests were conducted to assess the viability and variability of gravity separation for production of a tantalum pre-concentrate as well as monitoring the behaviour of other elements, notably niobium, tin and tungsten. QEMSCAN and XRF analyses of gravity separation products from the composite samples allowed insight into the effect of varying tantalum mineralogy on separation efficiency and a model was devised based on these results to predict the grade and recovery of tantalum for the eighteen composites. Compared to other operations, Tailson's Wodgina mine produces a pre-concentrate grade at 8% Ta20S, Haddington resources Ltd. Produces a pre-concentrate at 7.5% and Noventa's Morrua mine in Mozambique at 10% Ta205 (Serjak, 2004, Antonio, 2008).Tantalum grade after a rougher and cleaner Mozley table circuit was measured at 8.9% Ta20S and the combined tantalum recovery was 66%; this is greater than Tanco's sand recovery circuit at 55% , which has a similar size fraction (200-20 ~m), although their overall recovery reaches 70% (Flemming et aI, 1982) and Haddington's preconcentrate tantalum recovery is 65% (Serjak, 2004). The topaz granite contains variable levels of topaz which is heavy gangue mineral with a density ranging between 3.5-3.6 glcm3 (Barthelmy, 2010). This mineral is dominant in any concentrate produced from heavy liquid and gravity tests. Although its content is significantly reduced through gravity separation on the Mozley table, it remains at high levels and dilutes the concentrates. Niobium and tin were also shown to respond well to gravity separation. However, tungsten responds very poorly due its very fine grain size. It is the opinion of the author that further investigation into the extraction and refinement of these metals may lead to an economic added value product(s) if demand and prices for these metals is favourable. Although concentration by DMS upgraded the grain counts of tantalum mineralogy analysed by QEMSCAN, the grade was still too low to discern the variability of tantalum minerals within a single sample. This resulted in the model incorrectly predicting the Mozley table concentrate grade and recovery. Finally, a relationship between the mineralogy, mineral density and the tantalum and niobium assays of composites is proposed as well as a methodology to predict the mineralogical properties which affect the performance of mineral grains on the Mozley table. An integration of this estimated data is proposed and its uses outlined.
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Corbett, Helen Elizabeth. "Petrogenesis of the Tusas Mountain Granite, north-central New Mexico." The Ohio State University, 1986. http://rave.ohiolink.edu/etdc/view?acc_num=osu1343318854.
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Shimoyae, Akitsu. "Soil Erosion and Human Impacts in Hilly Devastated Granite Mountains." Kyoto University, 2003. http://hdl.handle.net/2433/148964.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第10235号
農博第1307号
新制||農||862(附属図書館)
学位論文||H15||N3756(農学部図書室)
UT51-2003-H656
京都大学大学院農学研究科森林科学専攻
(主査)教授 水山 高久, 教授 野渕 正, 教授 谷 誠
学位規則第4条第1項該当
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Frindt, Stephen. "Petrology of the Cretaceous anorogenic Gross Spitzkoppe granite stock, Namibia." Helsinki : University of Helsinki, 2002. http://ethesis.helsinki.fi/julkaisut/mat/geolo/vk/frindt/.
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Griffault, Lise. "Bilan des transferts de matière (majeurs et terres rares) dans les altérations hydrothermales des granites : exemple du granite du ballon d'alsace (vosges méridionales)." Poitiers, 1987. http://www.theses.fr/1987POIT2302.
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Etude de deux systemes d'alteration hydrothermale: - une alteration pervasive, se manifestant par la chloritisation des ferromagnesiens, le formation d'illite dans les plagioclases et la cristallisation de calcite; - une alteration a illite dans les epontes de veines liees a la mise en place de filins de fluorine. Cette etude montre que le comportement geochimique des terres rares ne peut etre assimile au comportement des elements majeurs au cours des processus hydrothermaux ou des mineraux argileux sont formes. Les mecanismes de fixation des terres rares correspondent a des phenomenes de sorption des elements sur les surfaces des particules argileuses et non a des substitutions
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Yu, Feng. "Failure characteristic of Hong Kong granite laboratory investigation and numerical simulation /." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23273100.
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