Thèses : « Metamorphic Metamorphism (Geology) »

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Rougvie, James Russell. « Metamorphism in the northern Park Range of Colorado : fluid-rock interactions and thermobarometry / ». Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.

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Standley, Carl E. « Banda forearc metamorphic rocks accreted to the Australian continental margin : detailed analysis of the Lolotoi Complex of East Timor / ». Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd1696.pdf.

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Cui, Xiaojun. « Numerical modeling of reactive fluid flow in the Notch Peak contact metamorphic aureole, Utah / ». free to MU campus, to others for purchase, 2002. http://wwwlib.umi.com/cr/mo/fullcit?p3060092.

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Walker, James David. « The structure and metamorphic evolution of the High Himalayan Slab in SE Zanskar and NW Lahaul ». Thesis, University of Oxford, 1998. http://ora.ox.ac.uk/objects/uuid:fc8b8fd3-e155-4f2f-9256-3667c2b31f4f.

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This thesis attempts to unravel the complex thermal and structural history of part of the High Himalayan Slab in NW India and combines reconnaissance-style field structural mapping of an area covering ~10,000 km² with petrography, microstructural analysis, thermobarometry and geochronology techniques. The results of this work show that the oldest protoliths of the High Himalayan Slab are at least Cambrian in age and that they may have experienced a major pre-Himalayan metamorphism at c.500 Ma. The youngest protoliths are Mesozoic in age (the Tandi Group) and demonstrate that the High Himalayan Slab represents the metamorphosed equivalents of the Tibetan Sedimentary Series. Metamorphism was achieved via substantial crustal shortening and thickening following the India-Asia collision at 50-54 Ma ago. Phase relationships demonstrate that metamorphism was a regional Barrovian-type event associated with the growth of biotite-, garnet-, staurolite-, kyanite- and sillimanite-bearing assemblages in metapelites. Quantitative thermobarometry demonstrates that near-peak conditions of c.6-8 kbar and 550-650°C were attained in the deepest exposed levels. Growth of metamorphic assemblages was underway by at least 30 Ma, as indicated by U-Pb ages of metamorphic monazites. Exhumation of the High Himalayan Slab was achieved through a combination of extensional unroofing along major detachments (namely the Zanskar Shear Zone), thermal doming, thrusting along the Main Central Thrust and surface erosion. Exhumation is closely associated with the growth of sillimanite- and cordierite-bearing assemblages in pelites and the generation and emplacement of crustal melt leucogranites in the upper parts of the slab. U-Pb dating of accessory phases from one of the crustal melt leucogranites (the Gumburanjon leucogranite) constrains its crystallisation and emplacement age at c.21-22 Ma. This is only slightly older than its ⁴⁰Ar/³⁹Ar muscovite and biotite cooling ages of c.20-21 Ma, which is attributed to the emplacement of the Gumburanjon leucogranite into the immediate footwall of the ZSZ. Field and geochronological data therefore support a strong temporal and spatial relationship between upper crustal melting and extension in a convergent orogen.

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Ambrose, Tyler. « Structure, metamorphism, and tectonics of the northern Oman-UAE ophiolite and underlying metamorphic sole ». Thesis, University of Oxford, 2017. http://ora.ox.ac.uk/objects/uuid:e9520624-0f91-4c9d-a9b9-e9e2fc5d5517.

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Ophiolites - thrust sheets of oceanic lithosphere that have been emplaced onto the continental margin - provide the opportunity to explore the structure and genesis of oceanic crust. As many ophiolites formed above subduction zones, they also allow for the investigation of mantle wedge and subduction interface processes. This the- sis examines the Oman-United Arab Emirates (UAE) ophiolite, which is the largest and most intensely studied ophiolite on Earth. Three distinct problems are addressed. (1) Recent research has proposed that the architecture and tectonic evolution of the ophiolite in the UAE differs from in Oman. In Chapter 2, I test this hypothesis by integrating new geological mapping and field observations with previously published maps of the ophiolite in the UAE. My results indicate that the ophiolite is gently folded, but otherwise largely intact. I demonstrate that the architecture of the ophi- olite in the UAE is not significantly different from in Oman. Thus, there is no basis for a different tectonic evolution as recently proposed. (2) Observations from exper- iments and small-scale natural shear zones indicate that volumetrically-minor phases can control strain localization. In Chapter 3, I test the hypothesis that minor phases control strain-localisation at plate boundaries. To do so, I analyzed peridotites from the base of the ophiolite, a palaeosubduction interface. My results demonstrate that minor phases limited olivine grain growth, which led to rheological weakening. (3) The mechanisms by which metamorphic soles detached from the downgoing slab and accreted to the hanging-wall mantle is unclear. In Chapter 4, I examine a transect across the metamorphic sole in the UAE. My results reveal that granulite formation was more extensive than is typically considered. I propose that granulite formation resulted in rheological strengthening, which caused the subduction interface to migrate into the downgoing slab and accrete the metamorphic sole.

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Strowbridge, Susan Leah. « Metamorphic evolution of anatectic metapelites from the Gabriel high strain zone, Grenville Province / ». Internet access available to MUN users only, 2005. http://collections.mun.ca/u?/theses,62592.

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Baker, Andrew James. « Metamorphic studies in the Scottish Highlands ». Thesis, University of Oxford, 1985. http://ora.ox.ac.uk/objects/uuid:0000df07-a390-4b43-af48-31f04ba628ec.

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Conditions of 8kb and 800°C are estimated for sillimanite K feldspar bearing metapelites and garnet-clinopyroxene bearing amnphibolites in Glen Muick. These conditions are inconsistent with the simultaneous nearby presence of equilibrium between andalusite and kyanite. Andalusite in the Glen Muick area is late. The sillimanite zone may have been in part primary. There is a transition without major structural break between Tay Nappe flat belt and the "Banff Nappe". A dataset has been derived for phases in the system KCMASHCO₂. The MHSRK equation of Kerrick and Jacobs (1981) has been used to extract data from mixed devolatilisation equilibria. Heats of formation are in agreement with calorimetrically determined values. Phlogopite equilibria calculated using disordered phlogopite data seem most appropriate to natural metapelite assemblages. Variations in pressure and temperature have been constrained across the Dalradian using various calibrated reactions. Temperatures vary from about 500°C in the low kyanite zone to 800°C in the sillimanite-K feldspar zone and pressures vary from 4kb to 10kb. Pressure estimates are justified on the basis that they are consistent with the aluminosilicate phase diagram. Rocks from the Central Highlands to Glen Clova underwent a decrease in pressure during evolution through peak metamorphic conditions. Amphibolites from the southern Moines show evidence of a former eclogitic assemblage of early Grampian age or earlier. High temperature regional metamorphic rocks lie at high structural levels and are are suggested to be an allochthonous unit, the Banff Nappe of Grampian age. The western margin of the Banff Nappe is marked by a temperature maximum to the immediate east, sharp thermal transitions, a train of metabasites and a high strain zone. It is suggested that emplacement of a Banff Nappe resulted in the deformation and metamorphism of structurally lower rocks.

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Huff, Timothy A. « Fluid inclusion evidence for metamorphic fluid evolution in the Black Hills, South Dakota / ». free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p1421144.

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Miller, Martin Gregg. « Structural and kinematic evolution of the Badwater Turtleback, Death Valley, California / ». Thesis, Connect to this title online ; UW restricted, 1992. http://hdl.handle.net/1773/6716.

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Tollefsen, Elin. « Thermal and chemical variations in metamorphic rocks in Nautanen, Gällivare, Sweden ». Thesis, Stockholms universitet, Institutionen för geologiska vetenskaper, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-149643.

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This study focuses on the geology of the Nautanen area. It is part of the SGU-financed project, Metamorphic Map of Sweden, which aims to compile metamorphic data from Sweden and takes the form of a number of Bachelor and Master projects. The main metamorphic event in the Nautanen area is the Svecokarelian Orogeny (1.96 – 1.75 Ga). The samples are metamorphosed sedimentary and volcanic rocks, which were intruded by intermediate to mafic intrusions and a later granite intrusion. The supracrustal rocks are folded and the Nautanen Deformation Zone (NDZ) traverses the area in a NW to SE direction. Petrographic studies, XRF analysis and THERMOCALC were used to estimate pressure and temperature and to elucidate evidence of fluid mobility. The average pressure was assumed to be below 4 kbar because of the presence of andalusite. The lowest and highest temperatures for metamorphism were 474±43°C and 681±14°C, with highest temperatures recorded nearest to the granite intrusion. XRF analysis revealed high concentrations of Ba (up to 7000 ppm) in the NDZ. High concentrations of Ba, skarn formation and replacement of garnet by chlorite indicate fluid-controlled metamorphism in the NDZ. The increasing temperature towards the granite intrusion suggests regional or contact prograde metamorphism that need not be related to the NDZ.
Metamorphic Map of Sweden, SGU-project

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Daczko, Nathan Robert. « The Structural and Metamorphic evolution of cretaceous high-P granulites, Fiordland, New Zealand ». University of Sydney. Geosciences, 2002. http://hdl.handle.net/2123/822.

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Fiordland is located southwest of South Island of New Zealand. The field area of this thesis is in northern Fiordland, at the boundary of pristine arc rocks (Median Tectonic Zone) and a belt of Paleozoic paragneisses and orthogneisses of variable age that represent the metamorphosed paleo-Pacific Gondwana margin.

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Hicks, Judith Anne. « Gahnite and its formation in the context of regional metamorphism and mineralization in the Namaqualand metamorphic complex ». Master's thesis, University of Cape Town, 1988. http://hdl.handle.net/11427/22024.

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Bibliography: pages 150-158.
Gahnite (ZnAl₂O₄) is commonly associated with sulphide mineralization in metamorphosed massive sulphide deposits, and also occurs in marbles, pegmatites and quartz veins. Its formation has been attributed to the breakdown of Zn-staurolite or desulphidation of sphalerite during metamorphism. The stability of zinc-rich spinels under a wide range of metamorphic conditions in a variety of lithologies results in its persistence in rocks where many other prograde, high temperature minerals and sulphides have been altered. Thfs has resulted in various investigations into its use in exploration and potential for determining metamorphic parameters. With the interest in finding new ore bodies and in determining the metamorphic history and mineralogy in Namaqualand, some gahnite-bearing localities have been investigated in this study.

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Mawby, Joanna. « Metamorphic and geochronologic constraints on Palaeozoic tectonism in the eastern Arunta Inlier ». Title page, table of contents and abstract only, 2000. http://web4.library.adelaide.edu.au/theses/09PH/09phm462.pdf.

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Appendix 4 and 5 in pocket on back cover. Bibliography: p. 123-130. The isotopic data indicates the Harts Range Metamorphic Complex formed within a previously unrecognized intracratonic tectonic province in Central Australia

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Bailey, David Elliott. « Metamorphic evolution of the crust of south-western Norway : an example from Sognefjord ». Thesis, University of Oxford, 1989. http://ora.ox.ac.uk/objects/uuid:9c297189-fe46-4d4d-8821-4fce08d5f5cd.

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It is suggested that the Mafic Units and HS are allochthonous and were emplaced onto the WGR during an early stage of the Caledonian Orogeny. All units, including the Basement Gneisses, have suffered retrogression during a late extensional phase which continued into at least the Middle Devonian.

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Lawrence, Robert William. « The structure and metamorphism of the Irindina supracrustal assemblage on the western side of the Entia Dome, Harts Range, central Australia / ». Title page, contents and summary only, 1987. http://web4.library.adelaide.edu.au/theses/09PH/09phl4225.pdf.

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Thesis (Ph. D.)--University of Adelaide, Dept. of Geology and Geophysics, 1987.
Typescript. Maps in back pocket of v. 1. Microfiches in back pocket of v. 2. Microfiches contain petrographic descriptions, total rock XRF analyses and microprobe analyses. Includes bibliographical references (leaves 160-183 (v. 2)).

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Trainor, Robert J. « Structure/kinematic and metamorphic analysis of the mesoproterozoic Novillo Gneiss, Tamaulipas, Mexico ». Ohio : Ohio University, 2010. http://www.ohiolink.edu/etd/view.cgi?ohiou1268932865.

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Barboza, Scott A. « Anatexis and metamorphism of crustal rocks during magmatic accretion : field and numerical results / ». Thesis, Connect to this title online ; UW restricted, 1998. http://hdl.handle.net/1773/6741.

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Schwarz, Steven H. « Structural, metamorphic and tectonic studies in Central Gagnon Terrane, Grenville Province / ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0034/MQ47431.pdf.

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Chavagnac, Valérie. « Behaviour of the Sm-Nd isotopie system during metamorphism : Examples from the HT-LP metamorphic terrane of the Limpopo Belt, South Africa and the UHP metamorphic terrane of Dabieshan, Central China ». Phd thesis, Université Rennes 1, 1998. http://tel.archives-ouvertes.fr/tel-00620022.

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Les buts de cette thèse sont (1) de déterminer si les âges modèles en Nd obtenus sur des terrains protérozoïques migmatisés correspondent réellement à l'âge d'extraction du magma de sa source mantellique (exemple du Limpopo Belt en Afrique du Sud) et (2) de comparer les âges Sm-Nd sur grenat et les âges U-Pb sur zircon déterminés sur des éclogites (exemple du Dabieshan en Chine Centrale). La Zone Centrale du Limpopo Belt est constituée principalement d'orthogneiss et de paragneiss. Elle a subi un métamorphisme granulitique suivi par des conditions métamorphiques de décompression à 2.0 Ga (trajectoire pression et température dans le sens horaire). Nous avons effectué des analyses isotopiques en Sm-Nd et U-Pb combinées aux analyses en éléments majeurs et traces sur trois examples de migmatites formées à 2.0 Ga afin d'étudier le fractionnement chimique et isotopique qui pourrait avoir lieu au cours de la migmatisation. La fusion partielle selon la réaction de déhydratation de la biotite met en exergue des comportements différents du système isotopique Sm-Nd dans les métagreywackes et dans les métapélites. Dans le premier cas, l'équilibre chimique et l'homogénéisation isotopique en Nd n'ont pas été achevés à cause de la fusion incongruente du plagioclase et de l'influence des minéraux accessoires sur la composition chimique des liquides. Il est démontré que la monazite est préférentiellement entraînée dans les leucosomes plutôt que l'apatite, provoquant ainsi la domination de la composition chimique de la monazite sur celles des liquides. De plus, la composition isotopique en Nd non-radiogénique de ce minéral accessoire domine celle du leucosome. Ainsi, les âges modèles en Nd des leucosomes sont jusqu'à 400 Ma plus vieux que ceux obtenus sur les paléosomes. Les âges modèles en Nd obtenus sur ces roches ne peuvent donc pas être uti lisés comme âge de formation de la croûte continentale en Afrique du Sud. Dans le cas des métapelites, la fusion incongruente du plagioclase a influencé la distribution des éléments majeurs, des Larges Ion Lithophi le Element ainsi que des Rare Earth Efement entre les paléosomes et les leucosomes. L'échange isotopique -en Nd entre les différents composants migmatitiques a été pratiquement atteint, au contraire des isotopes du Pb qui ne montrent qu'une homogénéisation partielle. Cependant, deux leucosomes à grenat présentent des compositions isotopiques en Sm-Nd et U-Pb supérieures aux autres composants migmatitiques. Ceci suggère qu'en règle générale les minéraux accessoires ont été chimiquement et isotopiquement équilibrés avec les leucosomes et les paléosomes. De ce fait, les âges modèles en Nd calculés sur les paléosomes et les leucosomes représentent des âges significatifs pour la formation de la croûte continentale dans la Zone Centrale du Limpopo Belt. Le dernier exemple est un orthogneiss migmatitique qui s'est formé par ségrégation métamorphique à des conditions subsolidus. La distribution des éléments majeurs et traces est directement proportionnelle à la quantité de chaque minéraux formant les composants migmatitiques. L'échange __ _ ___ _ isotopique en Pb a été achevé comme le montre l'isochrone en Pb-Pb sur les roches -:_~~ totales à 2.0 Ga. De plus, les caractéristiques géochimiques associées à une modélisation de la distribution des REE indiquent que le système est resté clos à - -----l'échelle de la roche totale durant le processus de migmatisation .. Ainsi, la composition isotopique en Nd du protolithe a pu être déterminée grâce à l'équation de conservation de masse et peut être utilisée pour défini~ l'âge de la formation de la croûte continentale. Le terrain Métamorphique de Ultra-Haute Pression (UHPM) du Dabieshan ______ est caractérisé par la présence de coésite et de quartz pseudomorphe dans les éclogites de composition basaltique mais aussi dans les roches d'origine sédimentaire. Les Isochrones en Sm-Nd sur grenat-omphacite-roche totale des éclogites à coésite du Massif de Bixiling donnent des âges variant entre 210 ± 9 Ma et 218 ± 4 Ma, très similaires aux âges U-Pb sur zircon à 218.4 ± 1.8 Ma et 218.4 ± 2.5 Ma (Ames et al., 1995). De plus, une isochrone Sm-Nd sur grenat-disthène-roche totale d'une éclogite rétromorphosée donne un âge à 231 ± 35 Ma en accord avec un âge à 233 ± 21 Ma (intercepte bas dans le diagramme concordia). Nous avons (:lffectué des datations par les méthodes Rb-Sr et Ar-Ar sur des phengites et des biotites de l'encaissant des éclogites à coésite de Bixiling. Les âges varient entre 198 ± 4 Ma et 212 ± 2 Ma recouvrant les âges précedemment obtenus par Sm-Nd sur les éclogites à coésite. Par conséquent, les âges Sm-Nd sur grenat sont en accord avec les âges U-Pb sur zircon et montrent que les gneiss quartzo-feldspathiques ont subi un événement métamorphique à -210 Ma comme les éclogites. L'homogénéisation isotopique en Nd entre les différents minéraux semblent être atteinte à l'âge du métamorphisme.

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Widanagamage, Inoka Hasanthi. « EMPA dating of Monazite from high grade metamorphic rocks along the Highland- Vijayan boundary zone, Sri Lanka ». Kent State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=kent1321633720.

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Friedman, Richard M. « Geology and geochronometry of the eocene Tatla Lake metamorphic core complex, western edge of the intermontane belt, British Columbia ». Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/28780.

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The Tatla Lake Metamorphic Complex (TLMC) underlies 1000 km² on the western side of the Intermontane Belt (1MB) northeast of the Yalakom fault Three fault-bounded lithotectonic assemblages are recognized in the area studied: an amphibolite grade gneissic and migmatitic core, structurally overlain by a 1 to 2.5 + km-thick zone of amphibolite and greenschist grade mylonite and ductilely sheared metamorphic rocks, the ductilely sheared assemblage (DSA), which is in turn structurally overlain by weakly deformed to unstrained subgreenschist grade rocks of the upper plate which flank the TLMC on three sides. Structures in the gneissic core include a gneissic foliation and schistosity (Sic), which has been deformed by west to northwest-trending tight to isoclinal folds (F2c). Tectonic fabrics observed throughout the DSA which formed during Ds deformation include a gently dipping mylonitic foliation (Ss), containing a mineral elongation (stretching) lineation (Ls) which trends towards 280° ± 20°. Minor folds of variable trend (Fs), almost exclusively confined to DSA metasedimentary rocks, are interpreted as coeval with ductile shear. Vergence of these folds defines movement sense and direction of top towards 290° ± 20°. Kinematic indicators from DSA rocks which have not been deformed by syn-ductile shear folds indicate a top-to-the-west sense of shear while those deformed by Fs folds yield conflicting results, with a top-to-the-west sense predominating. The entire lower plate comprising the TLMC has been deformed by broad, upright, west to west-northwest trending, shallowly plunging map-scale folds (F3) during D3, which deform Sic and Ss surfaces. The steeply dipping, northwest-trending Yalakom fault truncates all units and structures of the TLMC. Gently to moderately dipping normal faults of Ds and post-D3 relative age are the southern and eastern boundaries between DSA upper plate rocks and 1MB lower plate rocks. U-Pb zircon dates from igneous arid meta- igneous rocks from the lower plate range from Late Jurassic (157 Ma) through Eocene (47 Ma). These dates bracket the timing of Cretaceous (107 Ma to 79 Ma, in the core) and Eocene (55 Ma to 47 Ma, in the DSA) deformation and metamorphism in the lower plate. Biotite and hornblende K-Ai dates of 53.4 Ma to 45.6 Ma for lower plate rocks are in sharp contrast to Jurassic dates from nearby upper plate rocks; they record the uplift and cooling of the TLMC. Whole rock initial ⁸⁷Sr/⁸⁶Sr ratios (and for most samples present-day values) of less ≤0.704 have been determined for igneous and meta-igneous rocks of the TLMC; such values are typical of magmatic arc rocks of the 1MB and Coast Plutonic Complex of B.C. Whole rock major and trace element chemistry of lower plate igneous and meta-igneous rocks indicate sub-alkaline, calcalkaline, volcanic arc affinities. Garnet-biotite temperatures (interpreted as Eocene in age), from pelitic schist in the southern part of the DSA increase from about 400 ± 50 to 650 ± 50 C with increasing structural depth. A GT-BI-QZ-Al₂SiO₅ pressure of 8 ± 3 kb has been calculated for one of these samples. A T-P of 650 ± 50 C and 5.3 ± 3 kb, calculated from inclusions and garnet cores in a small pelitic pendant in the northwest part of the DSA, reflects conditions during intrusion of the surrounding 71 ± 3 Ma igneous body. A pressure of 7.2 ± 1.4 kb, based on the total Al in hornblende, has been calculated for this body. Cretaceous ductile deformation in the gneissic core may be related to folding and thrusting which occured in high level rocks to the west and east of the field area. During Early Eocene time (55-47 Ma) the TLMC acquired the characteristics of a Cordilleran metamorphic core complex. Mylonites of the DSA were emplaced by faulting beneath weakly deformed, low metamorphic grade rocks of the upper plate. Synchronously, metamorphic rocks of the gneissic and migmatitic core of the TLMC were moved to higher crustal levels along the footwall of the DSA normal ductile shear zone. The formation of F3 folds and final uplift of the TLMC (47-35 Ma) is postulated to be the consequence of transpression related to later Eocene dextral motion along the Yalakom fault The TLMC has structural style and timing of deformation similar to metamorphic core complexes in southeastern B.C. Local and regional evidence is consistent with the formation of the TLMC in a regional extensional setting within a vigorous magmatic arc.
Science, Faculty of
Earth, Ocean and Atmospheric Sciences, Department of
Graduate

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Tettelaar, Tanya Anne. « Emplacement history of the Pearly Gates anorthosite pluton and spatially related Tessiarsuyungoakh intrusion, and metamorphic petrology of the adjacent Tasiuyak paragneiss, northern Labrador / ». Internet access available to MUN users only, 2004. http://collections.mun.ca/u?/theses,61302.

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Piercey, Patricia. « PROTEROZOIC METAMORPHIC GEOCHRONOLOGY OF THE DEFORMED SOUTHERN PROVINCE, NORTHERN LAKE HURON REGION, CANADA ». Ohio University / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1149204676.

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Ho, Hoi-to Lucas, et 何海濤. « The Nielaxiongbo metamorphic core complex and its associated granites,in Southern Tibet ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B30252052.

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Moyer, Griffin Amoss. « Strain Accommodation, Metamorphic Evolution, And 3d Kinematics Of Transpressional Flow Within The Lower Crust Of A Cretaceous Magmatic Arc In Fiordland, New Zealand ». ScholarWorks @ UVM, 2019. https://scholarworks.uvm.edu/graddis/1110.

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The George Sound Shear Zone (GSSZ) exposed in Bligh Sound within Fiordland, New Zealand allowed us to reconstruct the kinematics of transpressive flow in >100 km2 of exhumed Cretaceous lower crust. We compare the three-dimensional characteristics of the deformation to theoretical models of transpression that assume steady-state flow in a homogeneous medium. This assumption is rarely the case for shear zones that experience metamorphism during deformation. We determined the three-dimensional kinematics of the GSSZ and evaluated the effects of metamorphism on strain accommodation and structural fabric evolution in the GSSZ to determine if metamorphism is an important parameter that transpressional models should account for. We found that metamorphism aided strain localization within the GSSZ and resulted in a style of structural fabric development that deviates from predictions made by theoretical models. We used foliation and lineation orientation data and field observations to determine GSSZ kinematics. Asymmetric pyroxene σ-porphyroclasts and hornblende fish show top-down-to-the-SW apparent normal shear sense with a sinistral component. The Z-axes of oblate SPO ellipsoids define the vorticity normal section and the moderately WNW-plunging vorticity vector. Foliation deflections relative to the shear zone boundaries yielded a vorticity magnitude (Wk) of ≥0.8. Our kinematic results suggest that the GSSZ records inclined, triclinic transpression with sinistral, top-down-to-the-SW simple shear-dominated flow. We used finite strain analysis and petrographic analysis to determine that metamorphism influences strain accommodation. Finite strain analyses were performed in 3D on 16 samples using the Rf/ɸ, Fry, and Intercept methods to determine the SPO fabric ellipsoids at different stages of deformation. Petrographic analysis was performed to identify metamorphic reactions using syn-kinematic minerals and constrain deformational temperatures using deformation mechanisms of plagioclase. Early deformation formed a ~13 km wide prolate fabric at granulite facies. Deformation later localized into a ~2-4.6 km wide oblate, mylonitic fabric at upper amphibolite facies. This fabric cross-cuts the prolate fabric and is characterized by metamorphic hornblende and biotite produced from retrogressive hydration reactions. Samples with syn-kinematic biotite contain more shear bands and display more grain size reduction of plagioclase than samples without this phase, suggesting these samples may have accommodated more strain. Changes in syn-kinematic metamorphic minerals were accompanied by steepening of stretching lineations and by changes in foliation orientation. Our analyses show that retrogressive hydration metamorphism aided strain localization within a cross-cutting oblate fabric, and the uneven distribution of biotite within this domain potentially influenced along strike variation in strain magnitude and fabric ellipsoid symmetry. Our results highlight the influence of fluid-induced metamorphism on shear zone evolution and call for new transpressional models to incorporate changes in rheology due to syn-kinematic metamorphism.

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Diener, Johann F. A. « The tectono-metamorphic evolution of the Theespruit Formation in the Tjakastad Schist Belt and surrounding areas of the Barberton Greenstone Belt, South Africa ». Thesis, Stellenbosch : University of Stellenbosch, 2004. http://hdl.handle.net/10019.1/16309.

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Thesis (MSc)--University of Stellenbosch, 2004.
ENGLISH ABSTRACT: The southern portions of the Early- to Mid-Archaean Barberton granitoid-greenstone terrain of South Africa consists of a high-grade metamorphic granitoid-gneiss terrain that is juxtaposed against the low-grade metamorphic supracrustal sequence of the Barberton Greenstone Belt. The boundary of the two different crustal domains corresponds to the Theespruit Formation, an amphibolite-facies, highly tectonized mélange of metabasites, felsic volcanics and rare, aluminous clastic sediments that occurs along the granitoidgreenstone margins. Amphibolite-facies lithologies in the Theespruit Formation are characterized by strongly prolate mylonitic fabrics that formed in a constrictional tectonic regime. Away from the granitoid-greenstone margin and towards the central parts of the greenstone belt, these rocks grade to, and are overprinted by, greenschist-facies S-L mylonites that formed during non-coaxial deformation. Both peak and retrograde minerals define, and are aligned parallel to, the fabrics in these rocks, indicating that shearing was initiated under peak metamorphic conditions and continued during retrogression. S-C’ fabric relationships indicate that shearing occurred in an extensional tectonic regime and that, during deformation, the gneiss terrain was uplifted relative to the greenstone belt. Peak metamorphic assemblages of grt-st-bt-chl-pl-qtz and ky-st-btms- pl-qtz in metasediments and grt-ep-hbl-pl-qtz in amphibolite constrain peak metamorphic conditions of 7.4 ± 1.0 kbar and 560 ± 20 ºC that were attained during the main accretionary episode in the Barberton terrain at 3229 ± 25 Ma. Peak assemblages in all rocks are pre-tectonic and were deformed and re-equilibrated during retrogression, resulting in these being minimum estimates of peak metamorphic conditions. Petrographic evidence and retrograde pressure-temperature estimates indicate that retrogression involved near-isothermal decompression of ca. 4 kbar prior to cooling into the greenschist-facies. The style and timing of metamorphism in the Theespruit Formation is similar to that of the granitoid-gneiss terrain, suggesting that the Theespruit Formation shares a geological history with the gneiss terrain and that it is allochtonous to the greenstone belt. The main deformational and fabric-forming event exhibited in the Theespruit Formation occurred during the exhumation of the granitoid-gneiss terrain subsequent to peak metamorphism. Consequently, the juxtaposition of this terrain againstthe greenstone belt was achieved by tectonic underplating and core complex formation at ca. 3.23 Ga. The occurrence of high-grade constrictional mylonites that are overprinted by low-grade non-coaxial mylonites as well as extension in an overall compressional tectonic regime is consistent with exhumation by extensional orogenic collapse. Burial of the high-grade terrain to depths of 25 – 30 km is only possible in a relatively cold and rigid crustal environment, while the extremely low apparent geothermal gradients of ca. 20 ºC/km preserved in this terrain suggest that burial and exhumation occurred rapidly, within a time-span of ca. 15 – 20 Ma. These parameters strongly suggest that metamorphism occurred in response to a lateral plate tectonic process that was operational in the Barberton terrain at 3230 Ma.
AFRIKAANSE OPSOMMING: Die suidelike dele van die Vroeg- tot Middel-Argaïese Barberton graniet-groensteen terrein van Suid-Afrika bestaan uit ‘n hoë-graad metamorfe graniet-gneiss terrein wat die lae-graad metamorfe groenstene van die Barberton Groensteen Gordel begrens. Die grens tussen die twee verskillende kors-domeine hang saam met die Theespruit Formasie, ‘n amfiboliet-fasies, getektoniseerde melange van metabasiete, felsiese vulkaniese gesteentes en skaars, alumineuse klastiese sedimente wat langs die graniet-groensteen kontakte voorkom. Amfiboliet-fasies gesteentes in die Theespruit Formasie word gekenmerk deur sterk prolaat milonitiese maaksels wat in ‘n vernouende tektoniese omgewing gevorm het. Hierdie rotse word weg van die graniet-groensteen kontak en na die sentrale dele van die groensteen gordel oordruk en vervang deur groenskis-fasies S-L miloniete wat tydens nie-koaksiale vervorming gevorm het. Beide piek en retrograad minerale definieer, en is georienteer parallel aan, die maaksel in die rotse, wat daarop dui dat skuifskeur onder piek metamorfe toestande begin het en volgehou het tydens retrogressie. S-C’ maaksels dui daarop dat skuifskeur in ‘n verlengende tektoniese omgewing plaasgevind het en dat die gneiss terrein opgehef is relatief tot die groensteengordel tydens vervorming. Piek metamorfe versamelings van grt-st-bt-chl-plqtz en ky-st-bt-ms-pl-qtz in metasedimente en grt-ep-hbl-pl-qtz in amfiboliet bepaal piek metamorfe toestande van 7.4 ± 1.0 kbar en 560 ± 20 ºC wat bereik is gedurende die hooffase van akkresie in die Barberton terrein teen 3229 ± 25 Ma. Die piek metamorfe versamelings in alle rotse is pre-tektonies en is vervorm en geherekwilibreer tydens retrogressie, wat maak dat die beramings minimum skattings van piek metamorfe toestande is. Petrografiese getuienis asook druk-temperatuur beramings dui daarop dat retrogressie gepaard gegaan het met byna-isotermiese drukverligting van naastenby 4 kbar voor afkoeling tot in die groenskis-fasies. Die styl en tydsberekening van metamorfose in die Theespruit Formasie is vergelykbaar met metamorfose in die granietgneiss terrein, wat daarop dui dat die Theespruit Formasie ‘n geologiese geskiedenis met die gneiss terrein deel en allochtoon is tot die groensteen gordel. Die hooffase van vervorming en maakselvorming in die Theespruit Formasie het plaasgevind gedurende die herontbloting van die graniet-gneiss terrein na piek metamorfose. Gevolglik is dieteenplasing van dié terrein teen die groensteen gordel vermag deur tektoniese onderplasing en kernkompleksvorming teen ongeveer 3.23 Ga. Die verskynsel van hoëgraadse vernoude miloniete wat oordruk word deur lae-graadse nie-koaksiale miloniete asook verlenging in ‘n algeheel saamdrukkende tektoniese omgewing dui daarop dat herontbloting plaasgevind het deur middel van verlengende orogenetiese ineenstorting. Die begrawing van die hoë-graadse terrein tot dieptes van 25 – 30 km is net moontlik in ‘n relatief koel en star kors-omgewing, terwyl die uitermate lae geotermiese gradiente van ongeveer 20 ºC/km wat in die terrein behoue gebly het daarop dui dat begrawing en herontbloting vinnig geskeid het, binne ‘n tydsverloop van ongeveer 15 – 20 Ma. Hierdie beperkings is ‘n sterk aanduiding dat metamorfose plaasgevind het as gevolg van ‘n laterale plaattektoniese proses wat werksaam was in die Barberton terrein teen 3230 Ma.

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Burri, Thomas. « From high-pressure to migmatisation : on orogenic evolution of the Southern Lepontine (Central Alps of Switzerland/Italy) / ». [S.l.] : [s.n.], 2005. http://www.zb.unibe.ch/download/eldiss/05burri_t.pdf.

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McLaren, Sandra. « The role of internal heat production during metamorphism of the Eastern Arunta Complex, central Australia, and the Mount Isa Inlier, Queensland / ». Title page, contents and abstract only, 1996. http://web4.library.adelaide.edu.au/theses/09SB/09sbm161.pdf.

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Thesis (B. Sc.(Hons.))--University of Adelaide, Dept. of Geology and Geophysics, 1997?
National Grid reference SF53-14 (Alice Springs), SF54-1 (Mount Isa) (1:250 000). Includes bibliographical references (leaves [32-36]).

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Chavagnac, Valérie. « Behaviour of the Sm-Nd isotopic system during metamorphism : examples from the HT-LP metamorphic terrane of the Limpopo Belt, South Africa and the UHP metamorphic terrane of Dabieshan, Central China / ». Rennes : Géosciences, Université de Rennes I, 1999. http://catalogue.bnf.fr/ark:/12148/cb370399598.

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Lewerentz, Alexander. « Fluid-induced alteration of metasedimentary rocks in the Scottish Highlands ». Doctoral thesis, Stockholms universitet, Institutionen för geologiska vetenskaper, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-146121.

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Fluids, mainly H2O and CO2, are released from H- and C-bearing phases during prograde metamorphism. Because of the buoyancy of these fluids, they rise within the crust towards the surface of the Earth. Metamorphic fluids take advantage of permeable horizons, shear zones, fold hinges, fractures, and are channelled into high-flux zones. Fluid fluxes for channelized fluid flow may exceed background pervasive fluxes by several orders of magnitude. Metamorphic fluids react with the surrounding rock during fluid flow, and altered zones are commonly observed adjacent to high-flux conduits. Fluid-altered rock is texturally, mineralogically, chemically, and isotopically different from rock unaffected by fluid flow. In this thesis, fluid-rock interaction is studied at two localities in the Scottish Highlands: Glen Esk and the Isle of Islay. Glen Esk is one of the type localities used by George Barrow (1853-1932) to propose the concept of metamorphic zones and metamorphic index minerals as an approximate determination of metamorphic grade. In several of the metamorphic zones in Glen Esk, index mineral distribution is highly dependent on proximity to veins. The occurrence of index minerals is therefore not only controlled by pressure and temperature, but also by the availability of metamorphic fluids. Evidence of a retrograde fluid flow event from the North Esk Fault is observed in Glen Esk, for which a time-averaged fluid flux of 0.0003 – 0.0126 m3∙m-2∙yr-1 is calculated. The duration of the fluid event is estimated to between 16 and 334 kyr. On the Isle of Islay, kyanite is observed in rocks of chlorite or lower-biotite metamorphic grade, i.e. much lower temperatures than usually associated with kyanite formation. The favoured explanation for this is retrograde infiltration of extremely high-CO2 fluids, at least locally XCO2 > 0.7, at ~340°C, which altered these rocks and stabilised kyanite in a carbonate-bearing assemblage. Oxygen and carbon stable isotope profiles across the Islay Anticline reveals highly channelized fluid flow along the axial region of this fold, with fluid:rock ratios at least four times higher than in rock farther away from the fold. Although carbon and oxygen isotope ratios of metacarbonate rocks were altered along the Islay Anticline, negative anomalies observed below and above the Port Askaig Tillite Formation cannot solely be attributed to metamorphic fluid flow, which implies that these rocks to varying degree retain their primary paleoclimatological isotopic signatures.
Stora volymer H2O och CO2 frigörs som fluider under prograd metamorfos. Metamorfa fluider har lägre densitet än det omgivande berget, varför de stiger genom jordskorpan mot jordytan. Metamorfa fluider kanaliseras i permabla lager, skjuvzoner, veckaxlar, sprickor och andra högflödeszoner. Kanaliserade fluidflöden kan vara flera storleksordningar högre än bakgrundsvärdet för fluidflöde inom en bergart. Metamorfa fluider reagerar under transport med det omgivande berget och bildar fluidomvandlade zoner i anslutning till högflödeskanaler. Fluidomvandlat berg uppvisar texturella, mineralogiska, kemiska och isotopsammansättningsmässiga skillnader i jämförelse med berg som inte utsatts för fluidomvandling. I denna avhandling behandlas reaktioner mellan fluid och berg som studerats i två lokaler i de skotska högländerna: Glen Esk och Islay. Glen Esk är en av de typlokaler som George Barrow (1853-1932) använde för att lägga fram konceptet om metamorfa zoner och metamorfa indexmineral som används för att ungefärligt uppskatta metamorf grad. I flera av de metamorfa zonerna är förekomsten av indexmineral i hög grad beroende av närhet till kvartsådror, vilket visar att bildandet av indexmineral inte bara styrs av tryck och temperatur, utan också av åtkomst till metamorfa fluider. I Glen Esk finns också spår av ett fluidflöde från North Esk-förkastningen, under retrograda metamorfa förhållanden, för vilket mededfluidflödet över tid uppgår till 0.0003 – 0.0126 m3∙m-2∙år-1. Denna fluidflödeshändelse beräknas ha pågått mellan 16 000 och 334 000 år. På ön Islay i de sydvästra högländerna återfinns bergarter, som trots sin låga metamorfa grad i klorit- eller biotitzonen innehåller mineralet kyanit, dvs. temperaturer långt under vad som vanligen associeras med kyanitbildning. Detta förklaras med infiltration av fluider med extremt hög CO2-halt, åtminstone lokalt så högt som XCO2 > 0.7, vid ca. 340°C. Fluidomvandling av dessa bergarter stabiliserade kyanit tillsammans med karbonatmineral. Syre- och kolisotopprofiler över Islayantiklinen påvisar hög kanalisering av fluider längs dess veckaxeln. Förhållandet mellan fluid och berg var mer än fyra gånger så högt i närheten av veckaxeln jämfört lokaler längre ifrån densamma. Påverkan av metakarbonatbergarters isotopförhållanden har skett längs Islayantiklinen, men fluidpåverkan kan inte ensamt förklara de isotopanomalier som observerats under och ovan Port Askaig-tilliten, varför dessa bergarter kan ha bibehållit sin primära paleoklimatologiska isotopsignatur.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 3: Manuscript.

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Nicoli, Gautier. « The metamorphic and anatectic history of Archaean metapelitic granulites from the South Marginal Zone, Limpopo Belt, South Africa ». Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97041.

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Thesis (DSc)--Stellenbosch University, 2015.
ENGLISH ABSTRACT: Anatexis is the first step in granite genesis. Partial melting in the lower crust may produce leucoratic features of unusual chemical compositions, very different from the final products of crustal differentiation. Therefore, the links that exists between some migmatites and crustal-derived granites can be ambiguous. This study is an investigation of the anatectic history of a high-grade terrain: the Southern Marginal Zone of the Limpopo Belt (SMZ), north to the Kaapvaal Craton in South Africa. The work involved an integrated field, metamorphic, geochemical and geochronogical study of the metasedimentary granulites from two separate quarries in the northern zone of the Southern Marginal Zone, the Bandelierkop quarry and the Brakspruit quarry, where Neoarchean high-grade partial melting features can be observed. The project has aimed to address two main issues: (1) to accurately constrain the pressuretemperature conditions and the age of the metamorphic episode in the SMZ, with implication for the geodynamic processes near the end of the Archean, (2) to investigate the fluid-absent partial melting reactions that control formation of K2O-poor leucosomes and to understand the chemical relationships in the system source-leucosome-melt–S-type granite. The P-T-t record retained in the Bandelierkop Formation metapelites, constrained by phase equilibria modelling as well as zircon LA-ICP-MS geochronology, gives an insight into crustal differentiation processes in the lower crust. Rocks in both quarries indicate high-temperature metamorphism episodes with peak conditions of 840-860 oC and 9-11 kbar at c. 2.71 Ga with formation of leucosomes (L1) during the prograde path. Minor leucocratic features (L2) were produced during decompression to 6-7 kbar. The end of the metamorphic event is marked by the granulites/amphibolites facies transition (< 640 oC) at c. 2.68 Ga. The maximum deposit age for the detrital zircons in the metapelites (c. 2.73 Ga) indicates a rapid burial process ( 0.17 cm.y1). Those evidences strongly support that the Southern Marginal Zone contains sediments deposited in an active margin during convergence, and that the metapelites were metamorphosed and partially melted as a consequence of continental collision along the northern margin of the Kaapvaal Craton at c. 2.7 Ga. The leucocratic features generated along this P-T-t path display an unusual chemistry with low K2O and FeO+MgO content and high CaO content. The combination of field observations, chemical mapping and geochemical analyses leads to the conclusion the major part of the leucosomes (L1) crystallized prior to syn-peak of metamorphism concurrent with melt extraction from the source. This study documents the details of leucosomes formation using field observations in the Southern Marginal Zone and numerical modelling. This work demonstrates that the formation of K2O-poor leucosome in the metasedimentary lower crust is controlled by the difference in volume of equilibration and heterogeneities within the migmatites. The partial melting of the source coupled with melt loss and water diffusivity within the melt transfer site is a potential mechanism to explain the chemical link in the sytem residuum– melt–S-type granite.
AFRIKAANSE OPSOMMING: Anateksis is die eerste stap in granietgenese. Meganismes wat in die onderste kors aan die werk is, is verantwoordelik vir korsdifferensiasie en bepaal die chemiese samestelling van die graniet. Hierdie studie het’n ondersoek behels van die anatektiese geskiedenis van ’n ho egraadse terrein: die suidelike randstreek van die Limpopo-gordel, noord van die Kaapvaal-kraton in Suid-Afrika. Die werk het ’n ge integreerde veld- , metamorfiese, geochemiese en geochronologiese studie van die metasedimentêre granuliete van twee afsonderlike groewe in die noordelike sone van die suidelike randstreek (SRS), die Bandelierkop-groef en die Brakspruit-groef, waar Neoarge iese ho egraadse gedeeltelike smeltkenmerke waargeneem kan word, ingesluit. Die projek was gerig op die ondersoek van twee belangrike kwessies: (1) om die drukâtemperatuurtoestande en die ouderdom van die metamorfiese episode in die SRS akkuraat te beheer, met implikasie vir die geodinamiese prosesse naby die einde van die Arge ikum, en (2) om die reaksies onder gedeeltelik gesmelte toestande wat die vorming van migmatiete beheer, te ondersoek en die chemiese verwantskappe in die stelsel bron - leukosoom - smelt - S-tipe graniet te begryp. Die P-T-t-rekord wat in die Bandelierkop-formasie metapeliete behoue is, ingeperk deur modellering van fase-ekwilibria asook sirkoon LA-ICP-MS-geochronologie, gee insig in korsdifferensiasieprosesse in die onderste kors. Rotse in albei groewe dui op metamorfismeepisodes teen hoÃ« temperature met piektoestande van 840â860 oC en 9â11 kbar teen ongeveer 2.71 Ga met vorming van leukosome (L1) gedurende die progradeerpad. Geringe leukokratiese eienskappe (L2) het tydens dekompressie tot 6â7 kbar ontstaan. Die einde van die metamorfiese voorval word gekenmerk deur die fasiesoorgang van granuliete / amfiboliete (<640 oC) by ongeveer 2.68 Ga. Die maksimum afsettingsouderdom vir die detitrale sirkone in die metapeliete (ongeveer 2.73 Ga) dui op Å snelle begrawingsproses ( 0.17 cm.y1). Daardie bewyse bied sterk ondersteuning daarvoor dat die SRS sedimente bevat wat gedurende konvergensie in Å aktiewe rand afgeset is, en dat die metapeliete gemetamorfoseer en gedeeltelik gesmelt het as gevolg van kontinentbotsing langs die noordelike rand van die Kaapvaal-kraton teen ongeveer 2.7 Ga. Die leukokratiese eienskappe wat langs hierdie P-T-t-pad opgewek word, toon Å ongewone chemiese samestelling met lae K2O en FeO+MgO-inhoud en ho e CaO-inhoud. Die kombinasie van veldwaarnemings, chemiese kartering en geochemiese ontledings lei tot die gevolgtrekking dat die grootste deel van die leukosome (L1) gekristalliseer het voor die syn-piek van metamorfisme tesame met smeltekstraksie van die bron. Hierdie studie het die besonderhede van leukosoomformasie met behulp van veldwaarnemings in die SRS en numeriese modellering opgeteken. Hierdie werk toon aan dat korsdifferensiasie in die metasedimentêre onderste kors deur Å ander volume van ekwilibrasie en heterogeniteite in die migmatiete beheer word. Die gedeeltelike smelting van die bron gepaard met smeltverlies en waterdiffusiwiteit tot in die smeltoordragterrein is ’n potensiele meganisme om die chemiese skakel in die stelsel residuum-smelt-S-tipe graniet te verklaar.

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Cox, Richard Alexander. « Eclogite facies metamorphism of mafic and ultramafic rocks in the Tshenukutish terrane, Manicouagan Imbricate Zone, eastern Grenville Province ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ54832.pdf.

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Worden, R. H. « Transmission electron microscopy of metamorphic reactions ». Thesis, University of Manchester, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234381.

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Rose, Shellie R. « Timing constraints and significance of Paleoproterozoic metamorphism within the Penokean orogen, northern Wisconsin and Michigan (USA) ». Ohio : Ohio University, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1090940526.

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Gupta, Saibal. « Structure and metamorphism of Sikinos, Cyclades, Greece ». Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363344.

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Dorans, Hugh. « METEX : An expert system for metamorphic petrography ». Thesis, Aston University, 1988. http://publications.aston.ac.uk/14370/.

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Classification of metamorphic rocks is normally carried out using a poorly defined, subjective classification scheme making this an area in which many undergraduate geologists experience difficulties. An expert system to assist in such classification is presented which is capable of classifying rocks and also giving further details about a particular rock type. A mixed knowledge representation is used with frame, semantic and production rule systems available. Classification in the domain requires that different facets of a rock be classified. To implement this, rocks are represented by 'context' frames with slots representing each facet. Slots are satisfied by calling a pre-defined ruleset to carry out the necessary inference. The inference is handled by an interpreter which uses a dependency graph representation for the propagation of evidence. Uncertainty is handled by the system using a combination of the MYCIN certainty factor system and the Dempster -Shafer range mechanism. This allows for positive and negative reasoning, with rules capable of representing necessity and sufficiency of evidence, whilst also allowing the implementation of an alpha-beta pruning algorithm to guide question selection during inference. The system also utilizes a semantic net type structure to allow the expert to encode simple relationships between terms enabling rules to be written with a sensible level of abstraction. Using frames to represent rock types where subclassification is possible allows the knowledge base to be built in a modular t'ashion with subclassirication frames only defined once the higher level of classification is functioning. Rulesets can similurly be added in modular fashio'n with the individual rules being essenrially declurative allowing for simple updating and maintenance. The knowledge base so far developed for metamorphic classification serves to demonstrate the performance of the interpreter design whilst also moving some way towards providing a useful assistant to the non-expert metamorphic petrologist. The system demonstrates the possibilities for a fully developed knowledge base to handle the classification of igneous, sedimentary and metamorphic rocks. The current knowledge base and interpreter have been evaluated by potential users and experts. The results of the evaluation show that the system performs to an acceptable level and should be of use as a tool for both undergraduates and rese:1rchers from outside the metamorphic petrogr:1phy field.

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Zumsteg, Cathy L. « Metamorphism of the Wales Group and Moria Group on Prince of Wales and Dall Islands, southeastern Alaska ». Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/5957.

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Thesis (Ph. D.)--University of Missouri-Columbia, 2007.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on December 28, 2007) Includes bibliographical references.

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Pressler, Rebecca E. « An integrated petrofabric study of the high-pressure Orlica-Śnieźnik Complex, Czech Republic and Poland ». Ohio : Ohio University, 2006. http://www.ohiolink.edu/etd/view.cgi?ohiou1149180445.

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GruÌˆtter, Hermanus Smalberger. « Structural and metamorphic studies on Ios, Cyclades, Greece ». Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.282815.

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Heiligmann, Martin. « Genesis and metamorphism of the Hemlo gold deposit, Ontario ». Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=100622.

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The worldclass Hemlo deposit is one of Canada's largest gold producers, containing 95 million tons of ore grading ~8 g/t Au; the mineralization is hosted mainly by two sub-parallel shear zones. However, unlike most Archean lode gold deposits, the ore occurs as finely disseminated Hg- and Ag-bearing native gold in potassically altered rocks, and is associated with molybdenite, stibnite and realgar.
Mineralization occurred at greenschist conditions (400 to 500°C), and was subsequently overprinted by a single metamorphic event that peaked at ~630°C and 5 to 7 kb, which recrystallized the ore and alteration assemblages. Retrograde cooling lasted for ~80 m.y., with temperature decreasing on average ~5°C per m.y. Ore formation involved three reactions that affected ∫S2,∫O2, and pH: the dissolution of sedimentary barite, the precipitation of pyrite, and the replacement of muscovite by K-feldspar. During sulfidation, caused by the dissolution of barite, iron partitioned preferentially into pyrite, which prevented the formation of Fe-bearing metamorphic index minerals (such as garnet and staurolite), oxides (e.g., magnetite, hematite, ilmenite), and low- ∫S2 sulfides (e.g., pyrrhotite). In addition, K-alteration strongly enriched the ore zones in K-feldspar (microcline) and muscovite, which buffered pH, and prevented formation of aluminosilicates. Hemlo is an example of a mesothermal deposit which formed from metamorphic fluids with a significant magmatic component. Deposition of native gold and molybdenite occurred due to decreases in pH and ∫O2 that accompanied potassic alteration and pyrite precipitation. Other elements, such as Sb and As were adsorbed initially onto pyrite growth surfaces. Near peak metamorphism, the deposit evolved a sulfide melt that formed through release of As and Sb from pyrite during metamorphic recrystallization, partial decomposition of primary minerals (such as native gold), and interaction of the melt with sulfur-bearing aqueous metamorphic fluids. The mineral assemblages that crystallized from this melt are similar to those predicted by experimental data for the As-Sb-S and related systems, and are interpreted to have formed by fractional crystallization.

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Grills, John Andrew. « Chemical, metamorphic and structural relationships of certain sheared metadolerites ». Thesis, Queen's University Belfast, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.484277.

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Primmer, T. J. « Low-grade Variscan regional metamorphism in south west England ». Thesis, University of Bristol, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370706.

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Poulton, Rachel Jane. « The structural and metamorphic evolution of Sifnos, Cyclades, Greece ». Thesis, University of Cambridge, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.243058.

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Chan, Heung-ngai. « Igneous and metamorphic rocks from SW Cyprus and NW Syria evidence for Cretaceous microplate collision and subsequent tectonic events in the Eastern Mediterranean / ». Click to view the E-thesis via HKUTO, 2004. http://sunzi.lib.hku.hk/hkuto/record/B30711940.

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45

Bendersky, Claire. « The onset of thermal metamorphism in enstatite chondrites / ». Connect to online version, 2006. http://ada.mtholyoke.edu/setr/websrc/pdfs/www/2006/189.pdf.

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46

Weiland, Richard John. « Emplacement of the Irian ophiolite and unroofing of the Ruffaer metamorphic belt of Irian Jaya, Indonesia / ». Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.

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47

McKee, G. (Gavin). « Evolution of the southwestern region of the Manicouagan reservoir, Grenville province, eastern Quebec : structural and metamorphic controls on the exhumation of high-pressure metamorphic rocks ». Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27549.

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The southwestern region of the Manicouagan reservoir occupies the structurally uppermost position in the Parautochthonous belt, in the Grenville province, in eastern Quebec. The region consists principally of well banded grey gneisses composed essentially of plagioclase, quartz and biotite. An assemblage of rocks consisting of dolomitic marbles, quartzites, iron formations and pelites, occurs throughout the region. This assemblage can be correlated to rocks in the tectonic foreland to the north of the Grenville Front, that were deposited on the continental margin of Laurentia during the Paleo-Proterozoic.
The east-striking, and moderately south-dipping, Utishku fault zone runs through the middle of the region, and juxtaposes eclogite-facies rocks to the north with amphibolite-facies rocks to the south. Kinematics on the Utishku fault zone are unclear. The relationship, however, of high-pressure rocks in the footwall, and lower-pressure rocks in the hangingwall, indicates a predominant normal fault motion. Mineral lineations on the Utishku fault zone plunge due south. Normal faulting was, therefore, oblique to the regional northwest-directed compression of the Grenville in eastern Quebec.
Mafic rocks from the Utishku fault zone preserve a prograde P-T path. In contrast, pelitic rocks from the Utishku fault zone preserve a retrograde P-T path. The mafic rocks were probably incorporated into the fault at a relatively late stage. It seems likely that the mafics were initially buried by a thrust fault, structurally below the Utishku fault zone, that was active synchronous to normal motion on the Utishku fault zone. The eclogite-facies rocks, to the north of the Utishku fault zone, may, therefore, be bounded by a thrust fault below and a normal fault above, that were coeval.
It is suggested that normal faulting and rapid exhumation of eclogite-facies rocks occurred synchronous to regional compression and relatively early in the history of the Grenville orogen.

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48

Hames, Willis E. « Multidisciplinary analysis of a polymetamorphic terrane, western New England ». Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-08232007-113000/.

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49

Forest, Richard C. « Structures and metamorphism of Ptarmigan Creek area, Selwyn Range, B.C ». Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63337.

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50

Miller, Stephen John. « High pressure acadian metamorphism of the Straits Schist, Western Connecticut ». Thesis, This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-03242009-040839/.

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Thèses sur le sujet « Metamorphic Metamorphism (Geology) »

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