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1
Hyslop, Ewan Kennedy. "Strain-induced metamorphism and pegmatite development in the Moine rocks of Scotland." Thesis, University of Hull, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.341013.
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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.<br>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.<br><p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: Submitted. Paper 3: Manuscript.</p>
3
Eriksson, Sarah. "Tracing the Origin of Metasedimentary Rocks in the Faroe-Shetland Basin." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-297082.
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The Faroe-Shetland region has been exposed to a long history of tectonic events and the geology in the area is rather complex. This history has led to the formation large metasedimentary deposits, though the origin of these deposits is not yet fully understood. Possible source areas are Greenland, Norway and Scotland. To give a further understanding of the geology in the Faroe-Shetland basin and its regional relationship this study will analyze metasediments to classify them and compare them with other related sediments. Geochemical, petrographical and isotopic data will be for classification. Through this comparison it is evident that the metasediments from the Faroe-Shetland basin contain remnants from several different deposits and cannot be rated to one specific origin. This is shown by the 143Nd/ 144Nd , 87Sr/ 86Sr and 206Pb/204Pb , 207Pb/204Pb, 208Pb/204Pb isotope ratios found in the Faroe-Shetland basin compared with other possible source areas from Greenland, Norway and Scotland. This has shown that the isotope from the Faroe region correlate well with Caledonian traces from both Greenland and Scotland. Though the Torridonian sandstone from Scotland can also be correlated with the metasediments in the Faroe-Shetland basin.<br>Regionen kring Färö-Shetland bassängen har blivit utsatt för en lång historia av tektoniska orogeneser och extensioner vilket har lett till geologisk komplexitet i området. Metasediment täcker stora delar av bassängen, men ursprunget av dessa avsättningar är ännu inte helt fastställt. Grönland, Skottland och Norge är några av de föreslagna ursprungsområdena till de sedimentära avsättningarna. För att fördjupa förståelsen kring dessa metasediment och deras regionala relationer till andra platser, så fokuserar denna studie på att jämföra och klassificera metasediment från Färö-Shetland bassängen. Geokemisk, petrologisk och isotopdata kommer användas för klassifikation, medan isotopdata huvudsakligen kommer att ligga till grund för jämförelsen av troliga sedimentära källor. Genom denna jämförelse så har det blivit tydligt att metasedimenten från Färö-Shetland bassängen innehåller spår från flertalet olika områden och avsättningarna kan inte enbart förklaras utifrån ett ursprungsområde. Detta framgår genom isotopförhållandena 143Nd/144Nd , 87Sr/86 Sr and 206Pb/204Pb , 207Pb/204Pb, 208Pb/204Pb, vilka hittats i Färö-Shetland bassängen i jämförelse med andra möjliga källor från Grönland, Skottland och Norge. Detta påvisar en komplex metasedimentär sekvens, en sekvens efter den komplexa tektoniska historian.
4
Ford, Frederick Dean Carleton University Dissertation Geology. "Petrology of the Flinton Creek ultramafic rocks, central metasedimentary belt, Grenville province." Ottawa, 1989.
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Taylor, Jeanne. "The anatectic history of Archaean metasedimentary granulites from the Ancient Gneiss Complex, Swaziland." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/20311.
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Thesis (DSc)--Stellenbosch University, 2012<br>ENGLISH ABSTRACT: This study is an investigation of the anatectic history of high-grade paragneisses from the Ancient
Gneiss Complex (AGC) in Swaziland. The work involved an integrated field, metamorphic,
geochemical, geochronological and structural study of metasedimentary granulites from three
separate, but spatially related areas of outcrop in south-central Swaziland, which were subjected to
multiple high-grade partial melting events throughout the Meso- to Neoarchaean. The project has
aimed to constrain the age(s) and conditions of metamorphism, so as to contribute to the
understanding of geodynamic processes in the Barberton and AGC granite-greenstone terranes, as
well as to investigate certain physical and chemical aspects of anatexis in the migmatites. The
metamorphic record retained in these rocks, constrained by phase equilibria modelling as well as
zircon and monazite SHRIMP and LA-ICP-MS geochronology, informs on the state of the mid- to
lower-crust of the southeastern Kaapvaal Craton during key events associated with early lithosphere
assembly and crustal differentiation. It also suggests that the region is comprised of more than one
high-grade terrane. Two of the areas investigated experienced high-temperature metamorphism at
ca. 3.23-3.21 Ga, in addition to a major 830-875º C, 6.5-7.6 kbar anatectic event at ca. 3.11-3.07
Ga. Intermediate and younger high-temperature events are recorded at ca. 3.18 Ga, ca. 3.16 Ga and
2.99 Ga. The timing of these metamorphic events coincided with the amalgamation of the eastern
domain of the proto-Craton via subduction and accretion of micro-continental fragments at ca. 3.23
Ga, including the Barberton Greenstone Belt (BGB) and AGC terranes, as well as discrete episodes
of crustal differentiation and potassic granitic magmatism between ca. 3.23 and 3.10 Ga. The third
area investigated holds no record of Mesoarchaean metamorphism, but instead experienced a 830-
855 ºC, 4.4-6.4 kbar partial melting episode at ca. 2.73 Ga. This broadly coincided with the
formation of a large continental flood basalt province, the ca. 2.71 Ga Ventersdorp LIP, and
widespread intracratonic granitic magmatism on the Craton towards the end of the Neoarchaean. An
explanation for the contrast in metamorphic record in the two terranes may be that the 2.71 Ga
granulites represent a much younger sedimentary succession, and that granulites from the older
terrane were left too restitic, after substantial partial melting during the Mesoarchaean, to record
subsequent high-grade events. Finally, this study documents the details of S-type granitic magma
production and extraction from a typical metapelitic source. Using the 2.73 Ga granulites from the
AGC as a natural field laboratory, a case is made for the selective entrainment of peritectic garnet to
the magma as a mechanism for generating relatively mafic, peraluminous S-type granite
compositions. The work demonstrates the evolution of entrained peritectic garnet in such magmas,
and is in strong support of a ‘peritectic phase entrainment’ process by which relatively mafic granite
magmas are produced from melts which, in theory, should be highly leucocratic.<br>AFRIKAANSE OPSOMMING: Hierdie studie ondersoek die anatektiese geskiedenis van hoëgraadse metasedimentêre gneise uit die
Ancient Gneiss Complex (AGC) in Swaziland. Die werk behels 'n geïntegreerde veld,
metamorfiese, geochemiese, geochronologiese en strukturele studie van metasedimentêre granuliete
van drie afsonderlike, maar ruimtelik verwante gebiede in suid-sentraal Swaziland, wat aan verskeie
hoëgraadse anatektiese gebeure onderworpe was gedurende die Meso-tot Neoargeïese tydsperiode.
Die studie is daarop gemik om die ouderdomme en die kondisies van metamorfose vas te stel, om
sodoende by te dra tot die begrip van die geodinamiese prosesse in die Barberton en AGC granietgroensteen
terrein, asook om sekere fisiese en chemiese aspekte van die anatektiese proses te
ondersoek. Die metamorfe rekord, bepaal deur mineraal ewewigsmodellering sowel as sirkoon en
monasiet SHRIMP en LA-ICP-MS geochronologie, belig die toestand van die middel-tot laer-kors
van die suidoostelike Kaapvaal Kraton tydens vroeë litosfeer samesmelting en differensiasie. Dit
stel ook voor dat die streek uit meer as een hoëgraadse terrein bestaan. Twee van die gebiede het
hoë-temperatuur metamorfose by 3.23-3.21 Ga ervaar, asook 'n hoof 830-875 ° C, 6.5-7.6 kbar
anatektiese gebeurtenis by 3.11-3.07 Ga. Intermediêre en jonger hoë-temperatuur gebeure was ook
by 3.18 Ga, 3.16 Ga en 2.99 Ga geregistreer. Die metamorfose van die gebied stem ooreen met die
samesmelting van die oos Kaapvaal Kraton domein deur subduksie en aanwas van mikro-kontinente
by 3.23 Ga, insluitend die Barberton en AGC terreine, asook diskrete episodes van kors
differensiasie en kalium-ryke graniet magmatisme tussen 3.23 en 3.10 Ga. Die derde gebied hou
geen rekord van Mesoargeïkum metamorfose nie. In plaas daarvan het dit 'n 830-855 ° C, 4.4-6.4
kbar anatektiese episode by 2.73 Ga ervaar, wat ooreenstem met die vorming van 'n groot
kontinentale vloedbasalt provinsie, die 2.71 Ga Ventersdorp Supergroep, en wydverspreide
intrakratoniese graniet magmatisme teen die einde van die Neoargeïkum. 'n Moontlike
verduideliking vir die kontras in metamorfe rekord in die twee terreine mag wees dat die 2.71 Ga
granuliete 'n jonger sedimentêre afsetting verteenwoordig, en dat granuliete van die ouer terrein te
restieties gelaat was na aansienlike anateksis in die Mesoargeïkum, om daaropvolgende hoëgraadse
gebeure te registreer. Ten slotte, hierdie studie dokumenteer die besonderhede van S-tipe graniet
magma produksie en ontginning van 'n tipiese metasedimentêre bron. Die 2.73 Ga granuliete word
gebruik as 'n natuurlike veld laboratorium om die selektiewe optel-en-meevoering van peritektiese
granaat tot die magma te ondersoek. Die werk toon die evolusie van peritektiese granate in sulke
magmas aan, en ondersteun lewering van relatiewe mafiese graniet magmas deur 'n ‘peritektiese
fase optel-en-meevoerings’ proses.
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Cope, Natalie J. "Thermochronology and geochronology of the Otter Lake region, QC, Central Metasedimentary Belt, Grenville Province." Kent State University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=kent1333295679.
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Rahmani, Amel. "Petrologie et geochimie d'une serie metasedimentaire dans le massif du khanfous (in ouzzal, hoggar, algerie)." Paris 6, 1992. http://www.theses.fr/1992PA066303.
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Le mole in ouzzal est un fragment de croute archeenne, metamorphise dans le facies granulite. Ce segment de croute est l'outil ideal pour l'etude des cratons anciens. L'etude des sediments et de granites associes, a permis de mettre en evidence des conditions metamorphiques de haute temperature (sa-qtz), de l'ordre de 1000c. Ces roches diversifiees traduisent une origine sedimentaire alimentee par des sources ultrabasique et acides. L'age de depot est tres mal contraint cependant, toutes les methodes radiometriques utilisees datent le metamorphisme granulitique a environ 2000 ma. L'etude des isotopes de l'oxygene a montre que ces roches ont preserve une memoire ante-metamorphique qui n'a pas ete perturbe par les transformations subies par la roche au cours du metamorphisme. Il en resulte qu'au cours de ce metamorphisme la quantite de fluide pervasif n'etait pas suffisante pour servir de vehicule aux echanges des isotopes de l'oxygene
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Ribeiro, Ligia Maria de Almeida Leite. "\"Estudo geológico-geocronológico dos terrenos granito-gnáissicos e sequências metavulcanossedimentares da Região do Betara (PR)\"." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/44/44141/tde-20032007-092356/.
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A Região do Betara, objeto desta pesquisa, localiza-se a nordeste da Cidade de Curitiba, entre os Municípios de Rio Branco do Sul e Campo Largo. Inclui Rochas granito-gnáissicas proto a miloníticas (Núcleo Betara) e seqüências metavulcanossedimentares de baixo a médio grau metamórfico (Formação Betara). Esses terrenos ocorrem na porção sul da Faixa Ribeira, em meio a seqüências metavulcanossedimentares da Formação Votuverava. Este trabalho teve como objetivo principal realizar estudos geológico-geocronológicos (UPb zircão) de rochas metabásicas associadas à seqüências metavulcanossedimentares (Formação Betara), bem como dos terrenos granito-gnáissicos proto a miloníticos (Núcleo Betara). Na região centro-sul do Betara, foram reconhecidas rochas granodioríticas proto a miloníticas formadas durante o paleoproterozóico (~2200 Ma) com heranças (núcleos de zircões) arqueanas (~2800 Ma). Valores arqueanos (~3200 Ma) foram obtidos através do método Sm-Nd (TDM) indicativos da época de derivação do manto dos protolitos crustais dessas rochas. Estes terrenos são limitados a sul pela Zona de Cisalhamento Lancinha, que baliza o domínio da Faixa Apiaí (à norte) daquele pertencente ao Complexo Atuba (a sul). Neste contexto tectônico, os terrenos granodioríticos proto à miloníticos representam lascas de embasamento, possivelmente relacionadas ao cráton do Paranapanema. Tal correlação, no entanto, não é tarefa fácil, uma vez que as características geológicas acopladas ao padrão geocronológico são bastante similares às observadas para o Núcleo Setuva (Siga Júnior et al., 2006 no prelo) e para o Complexo Atuba ( Siga Júnior et al., 1995 e Sato et al., 2003). Em contato tectônico com os terrenos granodioríticos ocorrem rochas sienograníticas proto a miloníticas, intimamente associadas a rochas metabásicas (mistura de magmas ? mixing, mingling). Os valores U-Pb (zircão) obtidos para os litotipos sienograníticos referem-se ao paleoproterozóico superior (1780 ? 1750 Ma; Kaulfuss, 2001 e Cury et al., 2003), similar às idades aqui obtidas para as rochas metabásicas (U-PB, zircão de 1789+-22 Ma). A ocorrência de rochas sienograníticas associadas a rochas metabásicas, com características anorogências, sugestivas de regimes extencionais representa um importante marco na região, relacionado à Tafrogênese Estateriana. Acrescente-se ainda a possibilidade de haver sedimentação associada a esse magmatismo de natureza anorogênica, relacionado a bacias do tipo rift desenvolvidas nesse período. Idades desse intervalo (1800 ? 1600 Ma) ocorrem no âmbito da Faixa Apiaí, em rochas sienograníticas proto à miloníticas do Núcleo do Tigre, a sul do corpo granítico Passa Três e no setor NE do batólito granítico Três Córregos (Kaulfuss, 2001; Cury et al., 2003 e Prazeres Filho, 2005). No continente Sul-Americano são reconhecidos ao longo de grande parte de sua porção centro-oriental (Província Borborema, Sistema Espinhaço, Grupo São João Del Rei, Província Tocantins e Faixa Ribeira), conforme discutido em Brito Neves et al. (1995). Esses registros tafrogenéticos, embora relativamente sincrônicos, variam em magnitude e extensão e são na maioria das vezes, caracterizados como rifts crustais com magmatismo de natureza alcalina ou sub-alcalina e sedimentação siliciclástica associada. Devem representar importantes cicatrizes associadas à rupturas de grandes massas continentais aglutinadas durante o Paleoproterozóico (Supercontinente Atlântica ? Rogers, 1996), ou mesmo durante o Paleo-Mesoproterozóico (Supercontinente Columbia; Rogers e Santos, 2002; Zhao et al., 2004). Os estudos geológicos relativos as seqüências metavulcanossedimentares (Formação Betara), em contato tectônico com os terrenos sienograníticos e granodioríticos (Núcleo Betara), permitiram reconhecer três unidades maiores: Sequência metapsamítica (basal) representada principalmente por quartzitos, uma Sequência de mármores, calciossilicáticas e metamargas (intermediária) e uma Sequência metapelítica (superior) onde predominam filitos com metabásicas associadas. Os dados geocronológicos obtidos através do método U-Pb (zircão) referem-se a corpos de rochas metabásicas (possíveis sills ou diques), que ocorrem intercalados concordantemente com a Sequência pelítica superior. O estudo petrográficos e geoquímicos desses corpos, embora bastante preliminar indica a natureza orto derivada dessas rochas e um quimismo de basaltos subalcalinos sugestivos de ambientes tectônicos distensivos. As idades obtidas do intervalo de 1500-1450 Ma são aqui interpretadas como mínimas de deposição da Formação Betara, possivelmente próxima desta. Valores de intervalo (1500-1450 Ma.) foram recentemente obtidos para as seqüências metavulcanossedimentares das Formações Votuverava, Perau e Água Clara. O Mesoproterozóico representa portanto, um importante marco relacionado a deposição de grande parte das seqüências metavulcanossedimentares do sul da Faixa Ribeira. O padrão geológico-geocronológico aliado ao padrão estrutural observado para a região do Betara, sugere que a colocação desses terrenos a níveis crustais superiores tenha ocorrido durante o Neoproterozóico, função de uma tectônica controlada em grande parte por cisalhamentos.<br>The Betara region was located at nothwest of the Curitiba City between the Campo Largo and Rio Branco do Sul municipal districts. This region includes granite-gnaissic rocks, proto to milonitics (Betara Nucleous) and metavolcanossedimentary sequences with low to intermediate metamorphic grade (Betara Formation). These terrains occur at the southern portion of the Ribeira Belt, surrounded by metavolcanossedimentary sequences of the Votuverava Formation. The main objective of this work was realize geologic-geochronologic studies (U-Pb zircon) of metabasic rocks associated with the metavolcanossedimentary sequences (Betara Formation), as well the metabasic rocks associated with the proto milonitic to milonitic granite-gnaissic terrains (Betara Nucleous). At the center-southern portion of the Betara Region, was recognized granodioritic rocks, proto to milonitic formed during the Paleoproterozoic (~2200 Ma) with archean inheritances (zircon nucleous ~2800 Ma). Archean values (~3200Ma) where obtained with Sm-Nd (TDM) method. This values where indicative for the mantle carries away ages for the crustal protolites of these rocks. These terrains are limited at the south by the Lancinha Shear Zone, who separates the Apiaí Domain (north) from the Atuba Complex (south). In this tectonic context, the proto to milonitc ganodioritic terrains represents peaces from the basement and possibly can be related to the Paranapanema Cratonic Region. This correlations are not a simple work and the geologic propers with the geologic patterns was to close to that observed for the Setuva Nucleous (Siga Júnior et al., 2006 no prelo) and for the Atuba Complex ( Siga Júnior et al., 1995 e Sato et al., 2003). In tectonic contact with the granodioritic terrains occurs some sienogranitic rocks proto to milonitics associated with metabasic rocks (magma mixing and/or magma mingling). The U-Pb zircon values obtained to the sienogranitic rocks was related to the Upper Paleoproterozoic (1780-1750 Ma; Kaulfuss, 2001 e Cury et al., 2003), very close to the ages obtained for the metabasic rocks (U-Pb zircon at 1789+-22 Ma). The occurrence of the sienogranitic rocks associated with metabasic rocks; with anorogenic characteristics may imply extensional systems and represents an important frame on this region, related to the Estatherian Tafrogenetic Event. Increases the possibilities to occur some sedimentation associated to this anorogenic magmatism, related to rift type basins developed during this period. Ages from this interval (1800 - 1600 Ma) occurs at the Apiaí Belt for the sienogranites proto to milonitics from the Tigre Nucleous at the south of the Passa Tres granitic body and at the nothwesthern portion of the granitic bathollite Três Córregos (Kaulfuss, 2001; Cury et al., 2003 e Prazeres Filho, 2005). In the South American Continent was recognized at a great part of this center west portion (Borborema Province, Espinhaço System, São João Del Rei Group, Tocantins Province and Ribeira Belt) according with Brito Neves et al. (1995). This tafrogenetic record was relatively synchronic, but variate in magnitude and extension and at most part of the time was related to crustal rifts with alkaline to sub alkaline magmatism associated with siliciclastic sedimentation. Might represent important scars associated with the breakage of some large continental masses agglutinated during the Paleoproterozoic (Atlantica Suercontinent, Rogers, 1996) or as same during the Paleo-Mesoproterozoic (Columbia Supercontinet; Rogers and Santos, 2002; Zhao et al., 2004). The geologic studies of the metavolcanossedimentary sequences (Betara Formation) in tectonic contact with sienogranitic-granodioritic terrains (Betara Nucleous) admit to recognize three major units: Metapsamitic sequence (lower), recognized mainly by quartzites, a marble, calciossilicatic and marly sequence (intermediary) and a metapelitic sequence (upper) where predominate phyllites associated with metabasic rocks. The geochronological data obtained from the U-Pb (zircon) method refers to metabasic rock bodies (dikes or sills) who occurs in conformity and intercalated with the upper pelitic sequence. The geochemical studies of this bodies indicates this ortho derived nature and a subalkaline chemical characteristics who suggests a distensive ambient. The ages obtained in a range between 1500-1450 Ma can be interpreted like minimal ages to deposition for the Betara Formation. Values at this same range (1450-1500 Ma) were obtained recently to the Votuverava, Perau and Água Clara Formations. The Mesoproterozoic represents an important frame related to deposition of the great part of the metavolcanossedimentary sequences of the southern Ribeira Belt. The geologic-geochronologic patterns, with the structural patterns observed to the Betara Region suggests whom the placement of this terraines at the upper crustal levels occurs at the Neoproterozoic, function of a shear-controlled tectonics.
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Grammatikopoulos, Tassos A. L. "Wollastonite skarn mineralization and associated plutonic rocks in the Grenvillian Central Metasedimentary Belt, SE Ontario." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0003/NQ42944.pdf.
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McEachern, Sally J. (Sally Jane) Carleton University Dissertation Geology. "Structure and U-PB geochronology of the Pembroke thrust stack, central metasedimentary belt boundary thrust zone." Ottawa, 1990.
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Woodhouse, Ailsa Jane. "Provenance of late archaean metasedimentary rocks on the southern Gawler craton : implications for its early crustal development /." Title page, table of contents and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09SB/09sbw889.pdf.
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Okonkwo, C. T. "The geology and geochemistry of the metasedimentary rocks of the Loch Laggan - Upper Strathspey area, Inverness-shire." Thesis, Keele University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355609.
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Duff, Jason. "A Geochemical and Isotopic Investigation of Metasedimentary Rocks from the North Caribou Greenstone Belt, Western Superior Province, Canada." Thèse, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/30972.
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The North Caribou Greenstone Belt (NCGB) lies at the core the granitoid-dominant North Caribou Terrane (NCT). Two sedimentary assemblages; the Eyapamikama (ELS) and Zeemal-Heaton Lake (ZHA) form the core of the NCGB.
Geochemistry of garnets from the orogenic Au deposit at Musselwhite suggest that the auriferous fluids have a contribution of metamorphic fluids and mineralization consisted of prolonged, multi-stage periods. Chemical zoning suggests changes in the influx of chalcophile and lithophile elements and that Au/sulphide ratios during nucleation were lower relative to later growth events.
Zircons from the ELS and ZHA suggest a c. 100 My hiatus in the onset of sedimentation, with the ZHA showing younger, “Timiskaming-type” ages. Age distributions from each assemblage reflect proximal, igneous sources. Nd isotopic compositions of the ZHA suggest a mixture of ancient and contemporaneous sources which are similar to external TTG rocks. Deplete mantle model ages of the ZHA rocks indicate a Mesoarchean inheritance.
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Thern, Eric Royal. "Geological Histories from 4372 Ma to 26 Ma Recorded in Siliciclastic Metasedimentary Rocks from the Central Yilgarn Craton." Thesis, Curtin University, 2012. http://hdl.handle.net/20.500.11937/69345.
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This study presents an investigation of detrital, metamorphic, and hydrothermal minerals from siliciclastic metasedimentary rocks of the Illaara and Maynard Hills greenstone belts, central Yilgarn Craton. This research assesses how 4.3 to 3.0 Ga detrital zircon populations came to be found in dispersed metasedimentary rocks, how these rock occurrences relate to each other and what this may reveal about the early Earth and the formation of the Yilgarn Craton.
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Sendek, Callie. "Using Structural Analysis to Assess Possible Formation Mechanisms of the Gneiss Domes of the Harvey Cardiff Domain, Eastern Ontario." Scholarship @ Claremont, 2012. http://scholarship.claremont.edu/scripps_theses/84.
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Gneiss domes are structural features associated with orogens worldwide. This study provides a structural analysis of the domes of the Harvey Cardiff Domain, associated with the Grenville Orogeny. Structural data and oriented samples were collected during field work in the summer of 2012. These were used in combination with published and unpublished foliation and lineation data to analyze structural patterns and determine a mechanism of formation for the domes. The end member scenarios for dome formation were taken from the gneiss dome classification scheme devised by Yin (2004). Most of these mechanisms were eliminated based on a lack of necessary large scale geologic features in the region of the study area. An analysis of the foliation pattern of the Cheddar and Cardiff domes was most consistent with formation by diapirism. However, the foliation patterns of the domes differ from the expected diapiric pattern, and seems to represent a non-horizontal slice through a diapir, cutting through a diapir neck in the north and a diapir hat in the south. This pattern can also be explained by rotation of diapiric foliation due to strain induced by the main orogenic event. This hypothesis was tested using COMSOL, a finite elastic strain model, and found to be realistic. With the methods used in this study it is not possible to tell whether this rotation occurred after or during dome emplacement.
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Gebremariam, Solomon Gebresilassie. "Nature and characteristics of metasedimentary rock hosted gold and base metal mineralization in the Workamba area, central Tigray, northern Ethiopia." kostenfrei, 2009. http://edoc.ub.uni-muenchen.de/10882/.
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Gebremariam, Solomon. "Nature and characteristics of metasedimentary rock hosted gold and base metal mineralization in the Workamba area, central Tigray, northern Ethiopia." Diss., lmu, 2009. http://nbn-resolving.de/urn:nbn:de:bvb:19-108823.
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Loan, MaryEllen Louise. "New Constraints on the Age of Deposition and Provenance of the Metasedimentary Rocks in the Nashoba Terrane, SE New England." Thesis, Boston College, 2011. http://hdl.handle.net/2345/2422.
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Thesis advisor: J. Christopher Hepburn<br>The Nashoba terrane of SE New England is one of three peri-Gondwanan tectonic blocks caught between Laurentia and Gondwana during the closure of the Iapetus Ocean in the early to mid- Paleozoic. U-Pb analyses (LA-ICP-MS) were carried out on zircon suites from the meta-sedimentary rocks of the Nashoba terrane. The youngest detrital zircons in the meta-sedimentary rocks of the Nashoba terrane are Ordovician in age. There is no significant difference in age between meta-sedimentary units of the Nashoba terrane across the Assabet River Fault Zone, a major fault zone that bisects the NT in a SE and a NW par. Zircon in meta-sedimentary rocks in the Marlboro Fm., the oldest unit of the Nashoba terrane, is rare, which may reflect the basaltic nature of the source material, and is commonly metamict. The Marlboro Fm. contained the oldest detrital grain of all the analyzed samples, with a core of ~3.3 Ga and rim of ~2.6 Ga indicating that it was sourced from Archaen crustal material. Detrital zircons from the Nashoba terrane show a complete age record between the Paleoproterozoic and Paleozoic that strongly supports a provenance from the Oaxiqua margin of Amazonia. The detrital zircon suite of the Nashoba terrane is distinct from both Avalonia and the Merrimack belt; however, they resemble zircon suites from Ganderia. This study proposes that the Nashoba terrane of Massachusetts correlates with the passive trailing edge of Ganderia. Finally, metamorphic zircon analyses of the terrane show that the Nashoba terrane experienced a peak in hydrothermal fluid infiltration during the Neoacadian orogeny<br>Thesis (MS) — Boston College, 2011<br>Submitted to: Boston College. Graduate School of Arts and Sciences<br>Discipline: Earth and Environmental Sciences
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Roy, Baishali. "Structure and physical properties of the earth's crust in the Central Metasedimentary Belt, Grenville Province, Ontario from near vertical seismic reflection data." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq28520.pdf.
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Zeng, Lingsen Taylor Hugh P. "Non-modal partial melting of metasedimentary pendants in the southern Sierra Nevada and implications for the deep origin of within-pluton isotopic heterogeneity /." Diss., Pasadena, Calif. : California Institute of Technology, 2004. http://resolver.caltech.edu/CaltechETD:etd-10272003-131444.
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Séjourné, Brianna L. "Behaviour of Accessory Monazite and Age Significance During Metamorphism and Partial Melting During Grenville Orogeny: An Example from Otter Lake Area, Central Metasedimentary Belt, QC." Thesis, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31574.
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The accretionary Mesoproterozoic Grenville Orogeny (ca. 1300 – 980 Ma) involving the Central Metasedimentary Belt is a key building block of the eastern Laurentian margin. A petrographic, mineralogical, geochemical and geochronological study of the migmatite complex in Otter Lake (QC) within the Marble Domain is used to resolve regional metamorphic and magmatic events primarily recorded in the leucosome accessory minerals (i.e. monazite). The relationship between the different stages of monazite and garnet growth and dissolution during the tectonic evolution of the orogenic history for the interpreted metasomatic (injected) and anatectic (in situ) monazite-bearing neosomes from this study supports published thermochronological work in the area and challenges the claim that the Central Metasedimentary Belt was not heated above 500 °C during the Ottawan phase. Instead, the region shows Grenville magmatic and anatectic events were overprinted by high-temperature, fluid-rich Ottawan-phase metamorphism recorded within both injected (monazite-bearing) and in situ (monazite- and garnet-bearing) neosomes.
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Wang, Qian. "A geological traverse across the Jack Hills Metasedimentary Belt, Western Australia: Isotopic constraints on the distribution of proterozoic rocks and the evolution of Hadean Crust." Thesis, Curtin University, 2014. http://hdl.handle.net/20.500.11937/2275.
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Samples of every rock type present along a traverse through the Jack Hills belt were examined and processed for zircon, monazite and xenotime isotopic study. Zircon U-Pb ages range from 1618±22 Ma to 4381±5 Ma, confirming the presence of both Archean and Proterozoic successions. Lutetium-Hf data for Hadean zircons imply a primitive source that was reworked with little juvenile input from the mantle. Monazite data confirm that the Archean rocks were metamorphosed at 2.65 Ga.
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Lentz, David Richard. "Petrogenesis of uranium-, thorium-, molybdenum-, and rare earth element-bearing pegmatites, skarns, and veins in the central metasedimentary belt of the Grenville Province, Ontario and Quebec." Thesis, University of Ottawa (Canada), 1992. http://hdl.handle.net/10393/7941.
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Field examination of late-tectonic, U-, Th-, Mo-, and REE-bearing pegmatites, skarns, and veins in the southwestern Grenville Province indicates that they are spatially and temporally related. These observations lead to a renewal of the hypothesis that the deposits were related to intrusion of the pegmatites and formation of the skarns. The granitic pegmatites are related either to chemical fractionation of late-tectonic granitic plutons or mid-crustal anatectic melts with emplacement at the present structural level. This interpretation is based primarily on their discordant nature, late tectonic age, and moderately-evolved chemical composition. At the time of pegmatite emplacement the host rocks remained above 500$\sp\circ$C. Endoskarns (within pegmatite) are dominated by calc-silicate minerals (Ca pyroxene, scapolite, andradite, and titanite) and have a similar origin to the hybridized pegmatites involving metasomatic reaction of the pegmatite and skarn by either diffusion or infiltration of chemical components into the pegmatite. The exoskarns are dominantly primary with a mineralogical zonation which may be characterized as proximal to distal with relation to the pegmatite. The absence of calcite within the proximal skarn is explained in that the pegmatite-derived fluids were undersaturated in calcite resulting in dissolution. Calcite veins represent distal primary skarn. Secondary tremolite-phlogopite-sulphide replacement veins occur within the primary skarn. Fluorite-apatite-calcite veins, have inclusions and selvages of coarse-grained biotite, K-feldspar, Ca amphibole, Ca pyroxene, and titanite with occasional magnetite, sulphides, and rate-element minerals. Common minerals within the pegmatites, skarns, and veins facilitated a chemical comparison of these minerals. The colour of ferromagnesian phases, particularly Ca pyroxene and biotite/phlogopite was used in the field to describe the relative iron contents of these phases. In general, iron was highest in the minerals associated with the pegmatites, and proximal skarn; more magnesium rich in the skarns not directly associated with a pegmatite. Major- and trace-element distribution coefficients (K$\sb{\rm D})$ for coexisting phases in veins and skarns are indistinguishable, although only a few elements (Fe, Mg, Mn, and Zn) have regular distributions. In a more detailed study of the Hunt Mo skarn, four zones have been identified in the exoskarn which is, in part, consistent with observations from many other skarns in the region. The proximal zone 1 assemblage is narrow, coarse-grained (1 metre), and dominantly composed of Fe-rich Ca pyroxene, scapolite (or microcline or albite), titanite, pyrite, and molybdenite (rare quartz). The dominant skarn type, zone 2, is fine- to coarse-grained and consists of Fe-bearing Ca pyroxene, phlogopite/biotite, titanite, pyrite, and pyrrhotite, with irregular phlogopite (possibly secondary) veinlets throughout. Apatite is an accessory phase within zone 2 skarns. The third zone is composed of Ca pyroxene; phlogopite, and tremolite, and occasionally calcite and pyrite which are fine to medium grained. The fourth zone represents small veins hosted in graphite-bearing phlogopite-diopside-dolomite-calcite marble, and is dominated by fine- to medium-grained tremolite, phlogopite, calcite, pyrite $(\pm$ graphite). (Abstract shortened by UMI.)
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BODIN, EUGENE JOELLE. "Le devonien inferieur et moyen des pyrenees ariegeoises et centrales : biostratigraphie, series heteropiques et mise en evidence de nappes hercyniennes precoces." Toulouse 3, 1987. http://www.theses.fr/1987TOU30211.
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L'etude biostratigraphique, a l'aide des conodontes, du devonien inferieur et moyen des pyrenees ariegeoises et centrales a permis de distinguer 3 domaines paleogeographiques allonges selon l'axe de la chaine pyreneenne. Ils se dfferencient egalement par leur lithologie. On met en evidence une tectonique tangentielle varisque qui amene les series du nord a chevaucher les series sud et ces dernieres a chevaucher le substratum. Ces nappes precoces a vergence du nord vers le sud, d'ampleur plurikilometrique, constituent un trait essentiel de l'orogenese varisque pyreneenne
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Toteu, Sadrack-Félix. "Chronologie des grands ensembles structuraux de la région de Poli : Accretion crustale dans la chaîne panafricaine du Nord Cameroun." Nancy 1, 1987. http://www.theses.fr/1987NAN10057.
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Les nouvelles données structurales, géochimiques et géochronologiques indiquent un important volume de matériel d'âge protérozoïque supérieur dans le "complexe de base" et dans la "série de Poli". L'évolution tectonique et métamorphique est comparable pour les deux ensembles. Les caractéristiques géochimiques et isotopiques de l'essentiel des formations plutoniques et volcaniques de l'essentiel des formations plutoniques et volcaniques montrent qu'il s'agit de matériel juvénile nouvellement mis en place en bordure d'une croûte plus ancienne. Une chronologie des évènements panafricains est établie. Les nouveaux résultats permettent d'interprêter l'orogénèse panafricaine du Nord Cameroun en terme de tectonique des plaques
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Chisonga, Benny Chanda. "Metasedimentary manganese ores of the Serra do Navio deposit, Amapa Province, Brazil." Thesis, 2009. http://hdl.handle.net/10210/1952.
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Bjornerud, Marcia. "Structural evolution of a Proterozoic metasedimentary terrane, Wedel Jarlsberg Land, SW Spitsbergen." 1987. http://catalog.hathitrust.org/api/volumes/oclc/17281906.html.
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Thesis (Ph. D.)--University of Wisconsin--Madison, 1987.<br>Typescript. Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 187-194).
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Rector, Sharon. "Fabric analysis of deformed Proterozoic metasedimentary rocks, western Wedel Jarlsberg Land, Spitsbergen." 1987. http://catalog.hathitrust.org/api/volumes/oclc/17483160.html.
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Thesis (M.S.)--University of Wisconsin--Madison, 1987.<br>Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 91-95).
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Liao, Kelley. "Geochemical Diagnostics of Metasedimentary Dark Inclusions: a Case Study from the Peninsular Ranges Batholith, California." Thesis, 2012. http://hdl.handle.net/1911/71667.
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Dark enclaves rich in amphibole and biotite are ubiquitous in granitoid rocks and generally thought to represent fragments of mafic magmas, cumulates or restites. However, magmatic assimilation of metamorphic or sedimentary country rock can also form dark enclaves. To develop criteria for identifying dark enclaves of non-magmatic origin, we investigated dark enclaves from a complete spectrum of light (carbonate- or feldspar-rich) to dark (amphibole-rich, biotite-rich, or composite) enclaves, reflecting progressive thermal and chemical equilibration with host tonalite from the Domenigoni Valley pluton in the Peninsular Ranges Batholith, California. Metasedimentary dark enclaves have a number of major and trace element characteristics that overlap those of literature-compiled igneous dark enclaves. Comparison to modeled igneous differentiation paths shows metasedimentary enclaves can have anomalous CaO and K2O contents for a given SiO2, but other major element systematics may not deviate noticeably from igneous differentiation trends. In addition, the fact that there are literature-compiled mafic enclaves trending towards high K2O and high CaO suggests that not all mafic enclaves are of igneous origin. While the majority of dark enclaves may not be metasedimentary, this work provides some criteria for identifying enclaves should a case of metasedimentary origin arise.
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Gardner, David A. "Foliations in upper Proterozoic metasedimentary rocks of the Chamberlindalen area, Wedel Jarlsberg land, Spitsbergen." 1988. http://catalog.hathitrust.org/api/volumes/oclc/17574463.html.
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Thesis (M.S.)--University of Wisconsin--Madison, 1988.<br>Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 114-118).
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Luz, Filipa. "Multi-elemental and isotope geochemistry of metapelites from the Volcano-Sedimentary Complex (Iberian Pyrite Belt, Portugal) : unravelling fingerprints of different sources, sedimentary environments and exhalative-hydrothermal activity." Doctoral thesis, 2020. http://hdl.handle.net/10451/49765.
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Over the last two decades, promising steps have been made in the development of new greenfield and brownfield exploration methods for massive sulphide ore-forming systems in the Iberian Pyrite Belt (IPB). However, the effects of lateral and vertical facies variations in metasedimentary piles forming the two main lithostratigraphic units that potentially host massive sulfide deposits [the Phyllite-Quartzite Group (PQG) and the Volcanic-Sedimentary Complex (VSC)] on mineral exploration remain unknown. Massive sulphide deposits of the IPB document the progression of ore-forming processes in the SW Iberian Variscides, throughout uppermost Devonian to Early Carboniferous. Sulphide ores are usually hosted in volcanic-dominated or shale-dominated successions belonging to the VSC (Late Fammenian to Late Visean). Yet, several important orebodies at Neves Corvo are sitting within upper sections (Fammenian) of the early deposited Phyllite-Quartzite Group (PQG). Four key sectors of the Portuguese segment of IPB were revisited and 262 samples collected to characterize the geochemical features of metapelites from PQG and VSC sequences in barren and fertile settings. The selected sectors include active (Neves Corvo and Aljustrel) and old (Lousal) mines, besides promising brownfield (Gavião) and greenfield (Sesmarias) prospects, and other lithostratigraphic sections without known mineralization. The composition of PQG and VSC metapelites is similar and mainly controlled by a mixture of clayey-derived and quartz sandy-derived components largely resulting from different sources of granitic to granodiorite/quartz-diorite composition. Mineral transformations during diagenesis and/or hydrothermal alteration/mineralization partially overprinted the primary composition. During sedimentation/diagenesis, prevalent redox conditions were mostly confined to oxic environments, at places transiting to suboxic. Subsequent multi-stage interaction with reducing hydrothermal fluids (to which the sulphide mineralization is related) generated heterogeneous anoxic signs. Significant hydrothermal/mineralization imprints exist when Fe2O3/TiO2 ≥ 10 and Al2O3/(Al2O3+Fe2O3+MnO) ≤ 0.6. The 5x[(Fe2O3+MgO+MnO)/Al2O3], (Cu+Zn+Pb)/Sc and (As+Sb)/Sc geochemical ratios were recently proposed to separate barren from altered/mineralized metasedimentary successions in the IPB. When all these three ratios are above 10, a realistic vectoring towards massive sulphide accumulations occurs.
From this dataset, 98 samples were chosen to conduct a Pb-Nd-Sr isotope study from different sections of the PQG and VSC successions (from Givetian to Upper Visean), including footwall and hanging wall domains of mineralized horizons in Neves Corvo, Aljustrel and Lousal. An extensive review of the isotopic data for pelite rocks in the IPB allow the evaluation of their sources and the potential of radiogenic isotopes as exploration tools, when combined with trace element geochemistry. The whole-rock Nd and Sr isotopic compositions along with Th/Sc ratios shows that PQG and VSC sediments are mostly composed of a silicilastic mix supplied by the dismantling of an old basement: -11 ≤ ƐNdi ≤ -8; 87Sr/86Sri up to 0.727; and TDM ages ranging from 1.08 to 1.91 Ga (𝑥̅ = 1.67 ± 0.16 Ga). The rising of ƐNdi values recorded by many samples of upper VSC (up to ± 0.2 in the Aljustrel sector) is interpreted as a result of local incorporation of volcanic-derived contributions completed during sedimentation processes during and after Upper Tournaisian. The PQG succession, at times complemented by VSC thick piles, represent the main crustal reservoirs of metals that supplied the hydrothermal inflows in IPB, which were dominated by modified seawater. Other sources, more radiogenic, should be involved in the IPB metal budget when the role of Sn- and Cu-rich fluids became central in the ore system, as documented for the Neves Corvo deposit. The increasing of 207Pb/204Pbi ratios in sediments is sensitive to the circulation of mineralizing fluids. On the contrary, significant rise in 206Pb/204Pbi (and 207Pb/204Pb) values in sediments bearing disseminated sulphides other than pyrite only occur when conditions for a protracted interaction with radiogenic hydrothermal inflows of moderate to high temperature existed. The proximity to massive sulphide ore systems could be recognized in sedimentary levels of PQG and VSC whenever 207Pb/204Pbi > 15.60 together with other multi-elemental geochemical ratios such as Fe2O3/TiO2 and (Cu+Zn+Pb)/Sc > 10.
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Woodhouse, A. J. "Provenance of Late Archaean metasedimentary rocks on the southern Gawler Craton: Implications for its early crustal development." Thesis, 2002. http://hdl.handle.net/2440/123522.
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This item is only available electronically.<br>Geochemical, whole rock Sm-Nd and detrital zircon U-Pb isotopic data from Archaean metasedimentary successions in the southern Gawler Craton indicate derivation from Late Archaean sources. Detrital zircons from the upper amphibolite-grade Wangary Gneiss have dominant U-Pb age groupings at 2500-2580 Ma and 2600-2720 Ma, with a few analyses ranging up to 2950-3150 Ma. Steep LREE enrichment REE with (La/Yb)N = 46 – 58 and low abundances of compatible trace elements point to a major felsic source component, with REE patterns typical of Na-rich granites. Detrital zircons from the metasedimentary dominated Hall Bay Volcanics (2500-2560 and 2660-2710 Ma) show a similar range of detrital zircon ages to the Wangary Gneiss, suggesting both sequences were derived from a temporally similar Late Archaean source terrain. The Carnot paragneisses and the Hall Bay Volcanics metasedimentary rocks show comparative HREE enrichment ((La/Yb)N = 7.4-12.5 and (La/Yb)N = 10.2-15.7 respectively), suggesting a greater input of mafic or intermediate material relative to the Wangary Gneiss. The correspondence in detrital zircon ages between the Wangary Gneiss and Hall Bay Volcanic metasedimentary rocks suggests both units form part of the same succession. Existing zircon U-Pb data provides no evidence for input of Early Archaean crust into the Wangary Gneiss, Hall Bay Volcanics or Carnot paragneisses, which is further substantiated by Sm-Nd depleted mantle model ages that range from 2900 to 3200 Ma in all metasedimentary rocks. The overlap of detrital zircon and depleted mantle model ages suggests that all three successions in the southern Gawler Craton comprise a single basinal succession. The geochemical compositions of the late Archaean sequences in the southern Gawler Craton are consistent with derivation from a bimodal terrain with variable mixing of three distinct sources: (1) intermediate-felsic volcanics; (2) mafic rocks and (3) highly fractionated Na-rich felsic rocks (tonalites-trondhjemites). These source regions are currently unidentified in the Gawler Craton, however, source terrains for the late Archaean sequences may be preserved in association with the 2500-3000 Ma age crust in rifted off components of the Gawler Craton in Antarctica. Although speculative at this stage, deposition of the Late Archaean sequences in the southern Gawler Craton is likely to have occurred on a rifting margin to a Late Archaean terrain. Sedimentation was terminated during collisional closure of the basin system leading to the 2500-2400 Ma Sleafordian Orogeny.<br>Thesis (B.Sc.(Hons)) -- University of Adelaide, School of Physical Sciences, 2002
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Yeh, Chih-Ying, and 葉芝穎. "New constraints and interpretations on peak pressure-temperature conditions of metasedimentary rocks in the Yuli belt, eastern Taiwan." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/6n5846.
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碩士<br>國立東華大學<br>自然資源與環境學系<br>107<br>P-T conditions of the in-situ metasedimentary rocks in the Yuli belt are mostly unclear owing to lack of HP minerals or assemblages. To solve this problem, this study applied Raman Spectroscopy of Carbonaceous Material (RSCM) geothermometer to estimate peak metamorphic temperatures of metasedimentary rocks in the Juisui and Chinshuichi areas. In the Juisui area, from east (structurally lower) to west (higher), average temperature data of the four units are in the range of 385-414 °C, 478-532 °C, 380-421 °C, and 408-472 °C, respectively. In the Chinshuichi area, average temperature data of the two units are in the range of 497-505 °C (structurally lower) and 356-420 °C (higher), respectively. Average temperature data of the low-grade slate unit on the east side of the Yuli belt are in the range of 333-334 °C. The temperature results from the highest grade unit (Juisui unit) show a wide variation.
This study also applied Raman spectroscopy to constrain residual (entrapment) pressures of quartz inclusions in garnet from the highest grade units. Combining the RSCM thermometric results, the pressure-temperature condition of garnet-bearing pelitic schist samples are 16.8-17.8 kbar / ~590 °C and 13.9-14.7 kbar / ~550 °C, respectively. These results are consistent with those of high-pressure metamorphic rocks in the Yuli belt in previous studies.
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Barrett, L. "The structural geology of the Rapid BaySecond Valley area, Fleurieu Peninsula, South Australia." Thesis, 1995. http://hdl.handle.net/2440/128629.
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This item is only available electronically.<br>Whilst the geology of the Rapid Bay-Second Valley area is known to be both structurally and stratigraphically complex, previous workers (Daily, 1963; Evans 1987; Drayton, 1963; Campana and Wilson, 1955) have been unable to agree on many aspects of the area. Neoproterozoic and Cambrian aged sediments were first deposited in an extensional basin, which was formed due to lithospheric thinning, and associated subsidence (Jenkins, 1986, 1990). These rocks have then been subjected to at least one phase of deformation, the Cambro-Ordovician Delamerian Orogeny (Offler & Fleming, 1968; Thompson, 1970). Listric extensional faults were formed both before and during sedimentation of the rocks, which has created narrow zones of weakness that the subsequent compressional event has exploited, creating thrust faults (Flottman et al., 1994).
Structural mapping of the area has revealed that it is transected by two thrust faults and is intensely folded in places. Structural data has been collected during eight weeks of field work and has been compiled into a 1:10 000-scale geological map which accurately represents the area. A computer-generated three-dimensional model has been created for the area, based on this map, and cross and profile sections constructed from the data collected. The model was constructed using Vulcan™ software. Strain analysis has also been conducted on many of the folds in the area.<br>Thesis (B.Sc.(Hons)) -- University of Adelaide, School of Physical Sciences, 1995
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Howard, K. E. "Provenance of Palaeoproterozoic metasedimentary rocks in the eastern Gawler Craton, Southern Australia: Implications for reconstruction models of Proterozoic Australia." Thesis, 2006. http://hdl.handle.net/2440/123593.
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This item is only available electronically.<br>Detrital zircon ages obtained from the Corny Point Paragneiss and the Massena Bay Gneiss in the southeastern Gawler Craton, Australia, constrain their deposition to the interval ca. <1880 Ma. The presence of 2020 Ma, 2450 Ma and 2520 Ma detrital zircons within the Corny Point Paragneiss constrains the source region for the sedimentary protoliths to three possible domains within Australia; the Gawler Craton, the Glenburgh Orogen in the Western Australian Proterozoic, and the North Australian Craton, all of which contain rock systems with similar ages.
Whole rock εNd (1850Ma) values from the Corny Point Paragneiss range from -1 to -5. These values potentially preclude the Late Archaean to mid Proterozoic crust of the Gawler Craton as a sole or major source region due to its highly evolved average εNd (1850Ma) of around -10. Preclusion of the Gawler Craton as a source is apparently confirmed by Hf isotopic compositions of 2020 Ma detrital zircons from the Corny Point Paragneiss, which have εHf (2020Ma) ranging between +3 to +7. This compares with εHf (2020Ma) of -1 to -4 for zircons from the 2020 Ma Miltalie Gneiss in the Gawler Craton. Available Nd isotopic data suggests that the Glenburgh Orogen is too crustally evolved to have provided the majority of sediment into the Corny Point Paragneiss protolith. The 2020 Ma detrital Hf isotopic compositions of the Corny Point Paragneiss are similar to the 2020 Ma Wildman Siltstone (εHf (2020Ma) +2 to +7) in the Pine Creek Orogen in the North Australian Craton.
Two possible scenarios can be extrapolated from the detrital zircon and Nd isotopic data; (1) the Corny Point Paragneiss sediment was derived from a source region within the North Australian Craton and could share source regions with the Wildman Siltstone, or (2) the sediments were derived from a Gawler Craton source region that included a dominant juvenile component of the 2020 Ma Miltalie Gneiss in the adjacent Gawler Craton which has since been eroded. In the first scenario, the absence of connection to the Gawler Craton allows for the Betts and Giles (2006) plate reconstruction model, which proposes that the Corny Point Paragneiss formed part of the North Australia Craton, and was sutured to the Proto Gawler Craton at 1730-1700 Ma. The second scenario highlights a significant limitation in evaluating the significance of provenance data, particularly when considering old potential source terrains that have undergone significant levels of denudation. The proximity of the Corny Point Paragneiss to the rifted southern and eastern margins of the Australian Proterozoic means a thorough evaluation of the palaeogeographic significance of the Corny Point Paragneiss detrital signature requires corresponding datasets from regions such as Antarctica which were formerly contiguous with the Gawler Craton.<br>Thesis (B.Sc.(Hons)) -- University of Adelaide, School of Physical Sciences, 2006
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Alexander, Sharyn Anne. "Geological significance of deformed metavolcanic, metasedimentary, and plutonic rocks in the Composite Arc Belt, southwest Grenville Province, near Actinolite, Ontario." 2004. http://link.library.utoronto.ca/eir/EIRdetail.cfm?Resources__ID=81093&T=F.
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Palya, Annie P. "Storage and mobility of organic nitrogen and carbon in the continental crust: Evidence from partially melted metasedimentary rocks, Mt. Stafford, Australia." 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1463953.
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Fox, Don. "Structure, metamorphism and tectonic setting of metasedimentary rocks and mafic-ultramafic inclusions in the Dashwoods subzone of the Dunnage zone, southwestern Newfoundland /." 1992. http://collections.mun.ca/u?/theses,75451.
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[Verfasser], Solomon Gebresilassie Gebremariam. "Nature and characteristics of metasedimentary rock hosted gold and base metal mineralization in the Workamba area, central Tigray, northern Ethiopia / Solomon Gebresilassie Gebremariam." 2009. http://d-nb.info/999398962/34.
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Cao, Zheng Hong, and 曹恕中. "The geological significances of illite crystallinity, zircon fission-track ages, and K-Ar ages of metasedimentary rocks of the central range of Taiwan." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/61589133333717691389.
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Zeng, Lingsen. "Non-Modal Partial Melting of Metasedimentary Pendants in the Southern Sierra Nevada and Implications for the Deep Origin of Within-Pluton Isotopic Heterogeneity." Thesis, 2004. https://thesis.library.caltech.edu/4275/2/zeng-thesis.pdf.
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<p>Results from field mapping, structural analysis, major and trace element geochemistry, and radiogenic isotopic data from the Goat Ranch migmatite complex on the south shore of Lake Isabella, southern Sierra Nevada, California, are presented to (1) determine the major and trace element, Sr and Nd isotopic compositions of anatectic melts from pelitic sources; (2) investigate the structural and metamorphic responses of the Isabella pendant to the emplacement of the Goat Ranch pluton at ~100 Ma; and (3) evaluate the magnitude of assimilation of metasedimentderived melts by the Goat Ranch pluton at a mid-crustal level. Nd and Sr isotopic compositions were measured on the non-migmatitic distal wallrocks, leucosomes, migmatites, traverses into the Goat Ranch pluton, leucogranite dikes, and samples from the Rabbit Island, Heal Peak, and Bob Rabbit plutons. Major and trace element analyses were performed on selected samples of the leucosomes, migmatites and metapelites. Major and trace element analyses in addition to field and petrographic data demonstrate that leucosomes are products from partial melting of the pelitic protolith host. These data show that (1) contamination of Goat Ranch intrusion is restricted to the immediate proximity to migmatitic wallrocks. Isotopic heterogeneity of the Goat Ranch intrusion is not related to assimilation at or near the level of exposure, but from a deeper source; (2) as compared to the metapelites, leucosomes have higher Sr and lower Sm concentrations and lower Rb/Sr ratios. Sr and Nd isotope compositions of leucosomes, migmatites and metapelites suggesting a disequilibrium partial melting of the metapelite protolith; (3) based on their Sr, Nd and other trace element characteristics, two groups of leucosomes have been identified. Group A leucosomes show distinct positive Eu anomalies, relatively high Rb, Pb, Ba and K<sub>2</sub>O contents, and low Rb/Sr ratios. Group B leucosomes have negative Eu anomalies, relatively low Rb, Pb, Ba and K<sub>2</sub>O contents, and low Rb/Sr ratios as well; (4) the leucogranite dikes also can be subdivided into Group A (high <sup>87</sup>Sr/<sup>86</sup>Sr(T) and low <font face="symbol">e</font>Nd(T)), and Group B (low <sup>87</sup>Sr/<sup>86</sup>Sr(T)) and high <font face="symbol">e</font>Nd(T)); (5) H<sub>2</sub>O-fluxed melting of quartz + plagioclase with minor involvement of muscovite melting dominated the leucosome production; (6) Group A leucogranite dikes resulted from partial melting of the lower pelite, and Group B dikes from partial melting of the upper pelite; and (7) the Bob Rabbit pluton represents an extreme end-member case that was derived completely from melting of the upper pelite or its equivalent in depth in the I-SCR (strongly contaminated and reduced I-type pluton) zone. Strain analysis shows that progressive partial melting resulted in the loading framework transition in the upper pelite unit from LBF structure (the stronger phase forms a load-bearing framework) to IWL structure (the weaker phase forms an interconnected weak matrix) with proximity to the pluton. The presence of melts has greatly affected the strain partitioning within the migmatite zone.</p>
<p>By incorporating accessory phase dissolution kinetics into non-modal partial melting of metasedimentary sources, theoretical modeling shows that non-modal partial melting of a pelitic source results in melts following two paths in <font face="symbol">e</font>Nd-<sup>87</sup>Sr/<sup>86</sup>Sr ratio space. Path 1 represents those partial melting reactions that favor muscovite/biotite dehydration and apatite but not monazite dissolution, leading to melts with elevated Rb/Sr, <sup>87</sup>Sr/<sup>86</sup>Sr, Sm/Nd, and <font face="symbol">e</font>Nd values. In contrast, Path 2 represents those partial melting reactions in which muscovite/biotite dehydration plays an insignificant role, and favor monazite over apatite dissolution, and lead to melts with lower Rb/Sr, <sup>87</sup>Sr/<sup>86</sup>Sr, Sm/Nd, and <font face="symbol">e</font>Nd values than their sources.</p>
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Burt, Emelia Anna. "Oxygen isotope studies of some sedimentary and metasedimentary rocks of the central and northern Appalachian Mountains, the Colorado Plateau, and the Ouachita Mountains." Thesis, 1993. https://thesis.library.caltech.edu/7295/1/Burt_ea_1993.pdf.
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<p>Terrigenous sedimentary rocks from the Colorado Plateau show a relatively
uniform bulk silicate δ^(18)O of +14.8 with an SEM of 0.32. Shales and calcilutites in this
region have a mean bulk silicate δ^(18)O of +17.7 which is significantly heavier than the
mean for interbedded sandstones and siltstones. Bulk silicate δ^(18)O is decoupled from
carbonate δ^(18)O due to differences in mode of deposition and diagenetic behavior.</p>
<p>Central Appalachian terrigenous sedimentary rocks show a surprisingly uniform
bulk silicate δ^(18)O of +14.8 with an SEM of 0.1. The mean bulk silicate δ^(18)O for all
shales (+15.2) is only 0.3 per mil heavier than the mean for all sandstones and siltstones
(+14.9). The oxygen isotope uniformity of Central Appalachian sedimentary rocks is
mainly a primary depositional feature that is the result of thorough, grand-scale mixing of
terrigenous sediment in the Appalachian geosyncline, probably involving several cycles of
sedimentation, uplift, erosion, and reworking extending over hundreds of millions of years
during the Paleozoic era. The bulk silicate δ^(18)O of siltstones and shales shows a
significant (P ˂ 0.05) correlation with conodont color alteration index, which is a measure of
diagenetic temperature. As a result of isotopic exchange with porewater during diagenesis,
the bulk silicate δ^(18)O of shales and siltstones can apparently be lowered by as much as 2.5
to 4.0 per mil. These diagenetic effects contributed to the overall homogeneity of these
sedimentary rocks because the shales started out at higher δ^(18)O.</p>
<p>A reconnaissance ^(18)O/^(16)O study of 14 samples of terrigenous sedimentary rocks
from the Ouachita Mountains suggests more inherent isotopic variation in these samples,
perhaps in part as a result of greater heterogeneity of source regions. Some of the isotopic
variation also seems clearly attributable to diagenetic effects. A significant (P ˂ 0.05)
correlation was found between mean vitrinite reflectance, also a measure of diagenetic
temperature, and the bulk silicate δ^(18)O difference between shale-sandstone pairs in three
different sedimentary formations.</p>
<p>Northern Appalachian metasedimentary rocks show a decrease in bulk
silicate δ^(18)O at garnet grade and higher. The terrigenous facies metamorphic rocks have
been depleted in ^(18)O by about two per mil relative to their unmetamorphosed counterparts
in the Central Appalachians, except where they are adjacent to carbonate-rich sections.
Carbonate facies metasedimentary rocks are 5 to 6 per mil higher than interbedded
terrrigenous facies rocks, but at the margins of that formation there is a distinct lowering of
bulk silicate δ^(18)O and carbonate δ^(18)O due to influx of metamorphic hydrothermal fluids
from the adjacent terrrigenous rocks. This is attributed to the involvement of isotopically
light fluids during metamorphism. Further work is need to elucidate the differences
between metamorphic processes in pelitic and calcareous sediments.</p>
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"Diffusion of oxygen and lithium isotopes at a contact between the Bushveld Complex and metasedimentary rock: Implications for the timescale of Phepane Dome diapirism." UNIVERSITY OF MARYLAND, COLLEGE PARK, 2009. http://pqdtopen.proquest.com/#viewpdf?dispub=1465548.
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葉晃伸. "Petrological and geochemical studies of the back arc basinal volcanic and metasedimentary rocks from Laohushan area, east section of north Qilian fold belt, NW China." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/51578930515655648981.
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