Dissertations / Theses: 'Metamorphic 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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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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Wartho, Jo-Anne. "Argon isotope systematics and mineralogy of metamorphic hornblendes from the Karakoram." Thesis, University of Leeds, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.304839.

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Sigler, Joshua T. "The metamorphic and structural evolution of the Davis Peak area, northern Park Range, Colorado." Laramie, Wyo. : University of Wyoming, 2008. http://proquest.umi.com/pqdweb?did=1798480831&sid=1&Fmt=2&clientId=18949&RQT=309&VName=PQD.

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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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Yun, Samuel. "Mechanical Analysis of a Detachment Shear Zone, Picacho Mountains Metamorphic Core Complex (AZ)." Thesis, University of Louisiana at Lafayette, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10814249.

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On I-10 between Tuscon, AZ, and Phoenix, AZ, is the Picacho Mountains Metamorphic Core Complex (MCC). The Picacho Mountains MCC represents the northwest of the Greater Catalina MCC which includes Tortolita, Santa Catalina, and Rincon Mountains. To the immediate south of I-10 is Picacho Peak, an early Miocene andesitic volcanic center, and opposite of Picacho Peak are the granitic Picacho Mountains. The detachment shear zone (DSZ) is well exposed at Hill 2437. The mylonitic DSZ is separated into an upper, middle, and lower plate by two detachment faults. The DSZ is estimated to have undergone deformation at ~500?C based on recrystallized quartz microstructures and a previous thermochronologic study by previous graduate student Maxwell Schaper. We obtained an average flow stress of 43 ? 9 MPa using a quartz paleopiezometer by Stipp and Tullis (2003). Using a flow law by Hirth et al. (2001), we found strain rate values between 10-13 and 10-12 s-1. Grain size analysis indicates that quartz recrystallized grains have relatively moderate aspect ratio (1.55 < Rf < 1.87) which correlates to small amount of finite strain (1.13 < Rs < 1.33). Results from vorticity analysis based on the recrystallized quartz grain shape foliation method reveals that quartz was deformed under ~60% pure shear and ~40% simple shear (0.48 < Wm < 0.70, assuming plane strain), and the DSZ experienced ~18% of shortening perpendicular to mylonitic foliation, and up to ~22% of stretching parallel to the flow plane up. We found that despite high strain rate values and evidence of high strain rate (e.g. undulose extinction in quartz, chessboard structures, cataclasites, and possible pseudotachylytes), this is not reflected in the amount of finite strain recorded by the mylonitic DSZ.

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Borel, Megan E. "A Microstructural and Geochronological Investigation of the Coyote Mountain Metamorphic Core Complex (AZ)." Thesis, University of Louisiana at Lafayette, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10814678.

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The Coyote Mountains is a metamorphic core complex that makes up the northern end of the 80-km long Baboquivari Mountain complex. The Baboquivari Mountain complex is composed of Mesozoic rocks, Cenozoic granites, pegmatites, and metasediments (Wright and Haxel, 1982; Haxel et al., 1980, 1984). In the Coyote Mountains, there is an intrusion of the Pan Tak granite, a muscovite-biotite-garnet peraluminous granite dated at 58 Ma based on U-Pb analysis of zircon. The Pan Tak and other intrusions within the Baboquivari Mountains have been interpreted as anatectics melts representing the culmination of a Laramide crustal shortening orogenic event that started in the Late Cretaceous, about ~70 mya (Goodwin and Haxel, 1990). However, field evidence, as well as petrographic and microstructural analyses of metamorphic and deformational fabrics/structures show that the ~58 mya intrusive/magmatic fabric is overprinted by a secondary tectonic event. This event is particularly well recorded in the northern part of the Coyote Mountains, where a northdipping mylonitic shear zone is exposed. This study focuses on the Pan Tak granite with twenty samples from the northern portion of the Coyote Mountains, directly north of Coyote Peak, from the mapped areas of granites and mylonites.

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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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Christy, Andrew Gregor. "The structure and stability of sapphirine in relation to its metamorphic environment." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.278298.

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Krabbendam, Maarten. "Structural and metamorphic evolution of eclogite gneisses during exhumation in SW Norway." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389057.

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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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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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Moore, John Michael. "A comparative study of metamorphosed supracrustal rocks from the western Namaqualand metamorphic complex." Doctoral thesis, University of Cape Town, 1986. http://hdl.handle.net/11427/22585.

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Bibliography: pages 346-370.
A regional study of highly metamorphosed supracrustal rocks was undertaken in the western portions of the Namaqualand Metamorphic Complex. The study area was essentially restricted to a north-south section some 50 kilometres wide and 220 kilometres long. Eight east-west-trending belts of supracrustal rocks were examined, together with several smaller paragneiss remnants, in an area dominated by quartzo-feldspathic gneisses of granitic composition. The supracrustal rocks were classified into seven major lithological groups: quartzitic rocks, metapelitic and metapsammitic rocks, quartzo feldspathic rocks, metabasites, metacarbonate rocks, magnesium-rich cordierite rocks and iron formations. Further subdivision, based on variations in mineral constituents within each group, also occurred, as well as the presence of lithologies with compositions transitional between certain groups. The various supracrustal sequences were subdivided into formations containing minor distinctive members on an informal lithostratigraphic basis. Correlation between the major supracrustal belts was then undertaken. Four subgroups were identified across the study area, comprising a quartzo feldspathic gneiss subgroup and an overlying feldspathic quartzite/garnetcordierite gneiss subgroup that both predominate in the southern and central part of the area, a glassy quartzite/mica- sillimanite schist subgroup that predominates in the northern part, and a cordierite gneiss/metacarbonate subgroup that is restricted to the Geselskapbank synform. The supracrustal rocks appear to have been emplaced on a basement of augen gneisses. This relationship is, however, complicated by the intrusion of granit i c rocks within the contact zone.

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Dean, Andrew. "Upper Palaeozoic palynomorphs from the low grade metamorphic rocks of Devon and Cornwall." Thesis, University of Exeter, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.303917.

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Konrad-Schmolke, Matthias [Verfasser], and Patrick [Gutachter] O'Brien. "Thermodynamic and geochemical modeling in metamorphic geology / Matthias Konrad-Schmolke ; Gutachter: Patrick O'Brien." Potsdam : Universität Potsdam, 2017. http://d-nb.info/1218402547/34.

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Schaan, Susan. "Stratigraphy, structure and metamorphic petrology of the Turner Lake area, Archean Slave Province, Northwest Territories." Thesis, University of Ottawa (Canada), 1994. http://hdl.handle.net/10393/9677.

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Lithological, metamorphic and structural relationships are established in the Turner Lake area of the Archean Hood River supracrustal domain. Four map units define a stratigraphic sequence of subvertical beds that appears to young eastward. Metamorphosed greywacke to mudstone turbidites (Unit 1) are overlain with local discordance by polymict conglomerate (Unit 2, James Falls Conglomerate) with clasts mainly of diorite, volcanic and sedimentary rocks interpreted to be of local origin. An intercalated metamorphosed sequence (Unit 3) of arenite, layered volcaniclastic rocks, breccia and conglomerate (including tonalite cobbles), pyroxenite and dioritic to gabbroic intrusions, is apparently overlain further east by a second sequence (Unit 4) of greywacke-mudstones. Sheet-like trondhjemitic to tonalitic intrusions, one with a U-Pb zircon age of 2607 $\pm$ 1.3 Ma, are common within Unit 3; minor tonalitic sheets intrude Unit 1. Larger plutons include the (2600 $\pm$ 2 Ma, U-Pb zircon) Pistol Lake granodiorite to tonalite in the south and the Fish-hook Lake monzogranite in the west. Proterozoic diabase dykes of at least three ages cross-cut the Archean rocks. Metagreywacke-mudstones of Units 1 and 4 have similar rare earth element signatures and may be derived from a similar source terrane. The signatures resemble those of Yellowknife Supergroup metasedimentary rocks in the Yellowknife area. Trace element signatures of epiclastic amphibolites and mafic tuffs suggest mixed ultramafic and felsic sources. They may be consanguineous with the metapyroxenite. Highly foliated tonalite sheets and less deformed trondhjemite sheets have similar whole rock and rare earth element signatures to the Pistol Lake pluton. The lack of negative europiom anomalies in the rare earth element signatures of the plutonic rocks is comparable to synkinematic granites in the Yellowknife area. (Abstract shortened by UMI.)

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Strickland, Evan. "Geology of the Footwall of the Northern Plomosa Mountains Metamorphic Core Complex, West-Central Arizona." Thesis, Colorado State University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10640375.

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The northern Plomosa Mountains is a N-S trending range in the lower Colorado River Extensional Corridor, west-central Arizona—a region which hosts several highly extended terrains known as metamorphic core complexes. Metamorphic core complexes are characterized by low-angle normal faults (detachment faults) which have accommodated tens of kilometers of extension, and juxtapose a brittlely-deformed hanging wall against a ductilely-deformed footwall. The primary structural feature of the northern Plomosa Mountains is the Plomosa detachment fault, a gently-dipping low-angle normal fault. Though 1:24,000 scale geologic mapping had previously been conducted in the northern Plomosa Mountains, little work had been done in the metamorphic footwall of the Plomosa detachment fault, which was the focus of this study.

New 1:10,000-scale geologic mapping, structural and microstructural analysis, and U-Pb zircon geochronology reveals that the footwall of the Plomosa detachment fault is dominated by early Miocene mylonitic fabrics associated with detachment faulting, demonstrating that the northern Plomosa Mountains is a metamorphic core complex similar to adjacent core complexes in the region. Three mylonitic units dominate the footwall of the Plomosa Mountains core complex: 1) Orocopia Schist, 2) an early Miocene intrusive complex, and 3) gneiss. The quartzofeldspathic Orocopia Schist encompasses 10.5 km2 of the northern Plomosa Mountains, and locally contains graphitic plagioclase porphyroblasts, and coarse-grained green actinolite pods 0.2–1.5 m wide are scattered throughout the Orocopia Schist. These pods are high in Mg, Cr, and Ni, strongly suggesting derivation from an ultramafic protolith. A laterally continuous unit of amphibolite (~3.5 km long, 10–150 m thick), interpreted as Orocopia metabasalt, is localized along a moderately SE-dipping contact between the Orocopia Schist and the gneiss, and contains metachert layers 3–30 cm thick. L>S mylonitic fabrics are common throughout the Orocopia Schist and gneiss, and a zone of L-tectonites is localized along their contact. The Miocene intrusive complex, which is dominated by biotite granodiorite and hornblende diorite, parallels the detachment fault along its eastern margin, and the gneiss is corrugated about a NE-trending subhorizontal axis.

Mylonitic fabrics have systematic NE-SW-trending lineations (average T/P = [220/09]), and record top-to-the-NE shear. The Plomosa detachment fault defines a broad NE-trending corrugation parallel to its slip direction, and on average dips ~12° to the NE. NW-striking normal faults, joints, and dikes throughout the footwall record NE-SW extension consistent with that of the mylonitic fabrics, indicating there was no change in extension direction between the ductile and brittle regimes. Dynamically recrystallized quartz grain sizes and mechanisms suggest the gneiss and the Orocopia Schist underwent amphibolite-facies mylonitization, locally with evidence of overprinting by upper- to middle-greenschist-facies mylonitization, whereas the Miocene intrusive complex dominantly records upper- to middle-greenschist-facies mylonitization. Based on the geometry and deformation conditions of footwall fabrics, three separate mylonitic shear zones were identified: I) A pre-Miocene, originally moderately NE-dipping (~50°) normal-sense shear zone which deformed the corrugated gneiss. II) An originally shallowly NE-dipping (~25°) normal-displacement Miocene shear zone, active before initiation of the detachment fault, and which primarily deformed the Orocopia Schist and Miocene intrusive complex. III) A detachment-subparallel Miocene shear zone that deformed rocks adjacent to the Plomosa detachment fault. The Miocene intrusive complex was mylonitized prior to exhumation by the Plomosa detachment fault, suggesting that magmatism slightly predated or was coeval with initiation of detachment faulting.

U-Pb zircon geochronology of the Orocopia Schist reveals an abrupt drop-off of Th/U ratios > 0.1 at 68–70 Ma, which demarcates the maximum depositional age of the Schist. A high density of Th/U ratios < 0.1 between 75–50 Ma zircons record metamorphism of the Schist after it was subducted. Xenocrystic zircons in the Miocene intrusive complex have an identical distribution of ages and Th/U ratios as the Orocopia Schist, indicating that the Schist was melted or assimilated during early Miocene plutonism. The early Miocene pre-detachment paleo-depth of the top of the Orocopia Schist is 3–4 km, suggesting a Paleogene exhumation event brought the Schist to upper-crustal depths after it was subducted beneath the crust.

Late-stage dextral and sinistral faults strike N and ENE, respectively, and associated barite and carbonate veins strike NE. These faults locally cut moderately-consolidated colluvium, and veins cut NW-striking joints and faults associated with detachment faulting. Together these structures record a minor phase of WNW-ESE extension, which is attributed to regional post-middle Miocene dextral faulting, with the northern Plomosa Mountains having occupied a transtensional step.

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Childe, Fiona. "Uranium-lead geochronology of metamorphic accessory minerals south of the Grenville Front, western Québec, Canada." Thesis, McGill University, 1992. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61060.

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U-Pb ages were determined on single grains of monazite and xenotime as well as small populations of rutile from amphibolite to granulite facies metasediments of the Quebec Gneiss Segment of the Grenville Province in an area extending 45 to 135 km south of the Grenville Front in La Verendrye Park, Quebec. Recent geochronological studies include Pb-isotope ratios of metamorphic minerals corresponding to ages of 2.5 to 2.65 Ga and U-Pb monazite ages to 2649 to 2655 Ma, which define a lower discordia intercept of approximately 1.01 Ga. Recent thermobarometric studies indicate the presence of two metamorphic episodes in the region.
Monazite and xenotime grains obtained from high grade metasediments at five locations between 45 and 70 km southeast of the Grenville Front yielded $ sp{207}$Pb/$ sp{206}$Pb ages of 999 $ pm$ 5 Ma to 1021 $ pm$ 2 Ma. Monazite from the norther part of this terrane also defined an upper intercept age of 2596 $ pm$ 3 Ma.
The southernmost sample location, 135 km south of the Grenville Front, yielded both monazite and rutile. Monazite gave an age of 1072 $ pm$ 2 Ma. Small populations of rutile yielded an age of 916 $ pm$ 2 Ma. (Abstract shortened by UMI.)

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Dransfield, Malcolm. "Extensional exhumation of high-grade metamorphic rocks in western Norway and the Zanskar Himalaya." Thesis, University of Oxford, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387017.

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Wellings, Simon Arthur. "Structural, metamorphic and thermal studies of the Dawros-Currywongaun-Doughruagh Complex, Connemara, Western Ireland." Thesis, University of Oxford, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.318588.

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Tadesse, Tarekegn. "A stratigraphic, structural and metamorphic analysis of Dalradian Rocks west of Ballater, northeast Scotland." Thesis, Queen's University Belfast, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241492.

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Trainor, Robert J. "Structural/Kinematic and Metamorphic Analysis of the Mesoproterozoic Novillo Gneiss, Tamaulipas, Mexico." Ohio University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1268932865.

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44

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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Koppens, Kohl M. "Petrographic Constraints on the Exhumation of the Sierra Blanca Metamorphic Core Complex, AZ." Thesis, University of Louisiana at Lafayette, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=10816907.

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The Sierra Blanca metamorphic core complex (SBMCC), located 90 miles west of Tucson, is part of the southern belt of metamorphic core complexes that stretches across southern Arizona. The SBMCC exposes Jurassic age sedimentary rocks that have been metamorphosed by intruding Late Cretaceous peraluminous granites and pegmatites. Evidence of this magmatic episode includes polysythetic twinning in plagioclase, albite exsolution of alkali feldspar resulting in myrmekitic texture, and garnet, mica and feldspar assemblages. The magmatic fabric is overprinted by a Tertiary (Miocene?) tectonic fabric, associated with the exhumation of the Sierra Blanca metamorphic core along a low-angle detachment fault, forming the SBMCC. The NW-SE elongated dome of metamorphic rocks forms the footwall of the detachment shear zone, and is separated from the hanging wall, composed of Paleozoic and Mesozoic metasedimentary rocks, by a low-angle detachment shear zone. Foliation is defined by gneissic layering and aligned muscovite, and is generally sub-horizontal, defining the dome. The NNW-SSE mineral stretching lineation is expressed by plagioclase and K-feldspar porphyroclasts, and various shear sense indicators consistent with a top-to the-NNW shear sense. Lineation trends in a NNW-SSE orientation; however, plunge changes across the domiform shape of the MCC. Much of the deformation is preserved in the blastomylonitic gneiss derived from the peraluminous granite, including epidote porphyroclasts, grain boundary migration in quartz, lozenged amphiboles, mica fish, and retrograde mineral alterations. Detailed petrologic observation and microstructural analysis indicate deformation temperatures of 450-575 ? ?C presented here provide thermomechanical constraints on the evolution of the SBMCC.

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Ghassemi, Mohammad Reza. "Tectonic evolution of the Late Archean Pontiac Subprovince, Superior Province, Canada: Structural, metamorphic, and geochronological studies." Thesis, University of Ottawa (Canada), 1996. http://hdl.handle.net/10393/9932.

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The Pontiac Subprovince is a Late Archean (ca. 2.7 Ga) metasedimentary-metavolanic-granitoid-gneiss terrane situated along the southeastern margin of the Superior Province in Quebec. Detailed structural study of the northwestern part of this amphibolite facies metasedimentary belt has revealed a protracted history of deformation in Late Archean and Early Proterozoic time. An early contractional event (D$\sb1$) resulted in development of steep foliations now preserved as folded or straight relics within microlithons of S$\sb2$ foliation. During this stage, the Cadillac-Larder Lake fault zone acted as a major fault zone along which greenstones for the Abitibi Subprovince were thrust over the Pontiac Subprovince. Regional metamorphism resulted from both thickening of the crust, and intrusion of voluminous I-type graintes. D$\sb2$ structures record peak metamorphic high-temperature deformation of the crustal rocks during which large-scale D$\sb2$ nappes moved towards the south-southeast. The basal thrust faults of these nappes are preserved as high-strain shear zones within the study area. Second order east-trending recumbent F$\sb2$ folds, a penetrative S$\sb2$ crenulation foliation, and a north-northwest-trending L$\sb2$ elongation lineation are other important structures of this deformational event. A later D$\sb3$ contractional event superimposed east-trending upright folds on all earlier structures. Extensional D$\sb4$ structures are associated with reactivation of the Cadillac-Larder Lake fault zone as a normal fault zone, and are only recorded in or close to normal faults within this fault zone. Finally, brittle D$\sb5$ thrust faults and kink structures are superimposed on all older structures in the northwestern Pontiac Subprovince. Gneisses of the Lac Opasatica area record pre-D$\sb1$ penetrative structures that are not present within the other rock types of the study area. Increasing metamorphic grade from biotite zone to sillimanite zone is evident from north (the Cadillac-Larder Lake fault zone) to south in the study area, close to outcrops of the S-type granites. Thermobarometry of samples from the study area indicates that regional metamorphism of the rocks in the northwestern Pontiac Subprovince occurred at about 590$\sp\circ$C and 6.2 kbar. Investigation of the metamorphic and structural history of these Late Archean rocks suggests a clockwise PT path similar to that of Phanerozoic collisional belts. $\sp{40}$Ar/$\sp{39}$Ar age constraints from this study combined with other geochronologic indicate a slow cooling rate of about 2$\sp\circ$ to 6$\sp\circ$C/Ma, and reveal that temperatures as high as 350$\sp\circ$C and 280$\sp\circ$C were persistent in crustal rocks of the area until ca. 150 Ma after attainment of peak metamorphic conditions. (Abstract shortened by UMI.)

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Bowman, Dannena Renee Steltenpohl Mark G. "Exhumation history of Caledonia eclogites in Liverpool Land, East Greenland, and comparisons with eclogites in Norway." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SPRING/Geology_and_Geography/Thesis/Bowman_Dannena_35.pdf.

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McDonald, Wayne M. Hames W. "⁴⁰Ar/³⁹Ar ages of muscovite from the western Blue Ridge and Talladega belt, Georgia and North Carolina." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SPRING/Geology_and_Geography/Thesis/Mcdonald_Wayne_42.pdf.

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Hollick, Louise Marie. "The metamorphic and structural evolution pf the Alpujarride complex (internal zone, Betic Cordillera, S. Spain)." Thesis, University College London (University of London), 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.271139.

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Evans, Marc. "Phenomena associated with tectonic discontinuities in the Scottish Metamorphic Caledonides, and their role during orogenesis." Thesis, University of Liverpool, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321119.

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Dissertations / Theses on the topic 'Metamorphic geology'

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