The stability of osumilite in metapelitic granulites. This hypothesis is supported by the similarities in U–Pb and Hf data between the protoliths of EGMB-south and the metasedimentary protoliths from the North Australian Craton, implying that the source could be the Antarctic for both the regions. In typical low-temperature eclogite, omphacite and garnet often coexist with glaucophane and clinozoisite over a fairly wide range of conditions. New approaches to crustal evolution studies and the origin of granitic rocks: what can the Lu-Hf and Re-Os isotope systems tell us?. Accessory Mineral Behaviour in Granulite Migmatites: a Case Study from the Kerala Khondalite Belt, India. The geochemistry and geochronology of the upper granulite facies Kliprand dome: comparison of the southern and northern parts of the Bushmanland Domain of the Namaqua Metamorphic Province, southern Africa and clues to its evolution. Granulite facies and eclogite xenoliths are plentiful in eastern Australia and Pearson & Oâ ReiUy demonstrate, on the basis of detailed petrography and geochemistry, that the xenoliths come from a depth of 35-75 km. . Mesoproterozoic granulites of the Shillong–Meghalaya Plateau: Evidence of westward continuation of the Prydz Bay Pan-African suture into Northeastern India. Segregation of leucogranite microplutons during syn‐anatectic deformation: an example from the Taylor Valley, Antarctica. Summary of the assembly and breakup history of India-Antarctica through different stages. Anatexis during High-pressure Crustal Metamorphism: Evidence from During this final assembly of Gondwana, the orogen was further deformed through thrusting and strike-slip shearing of the Rayner Complex against the Archean Napier Complex and the EGMB against the eastern margin of Archean Dharwar/Bastar cratons, (5) 0.3–0.2 Ga Permian–Triassic: the conjugate margins were crossed by a system of rift valleys, which accumulated the Gondwana succession of basal glacial sediments followed by coal measures and red beds, (6) 0.16–0.14 Ga Jurassic-Cretaceous: after preliminary rifting, continental breakup along the EGMB–Rayner complex, (7) to 0 Ma: the newly formed margins accumulated onlapping drift successions. The origin of high temperatures during regional low-pressure granulite facies metamorphism within the Proterozoic Broken Hill Block, Australia, has been reinterpreted to be the result of burial of anomalously ... tectonic setting, and its relationship to other similar Australian … It is contemporaneous with the Capricorn Orogeny and the Yapungku Orogeny in the West Australian Craton, and the Early and Late Strangways orogenies in the North Australian Craton, and may represent a series of intraplate and plate margin events reflecting convergence and accretion of the Gawler Craton to what was then the south-eastern North Australian Craton. Several bodies of charnockite and other granulite facies rocks occur in close association with garnet-bearing gneisses (Fig. Ukwang, E. E. and Ekwueme, B. N. (2009). and you may need to create a new Wiley Online Library account. Ultra-high temperature overprinting of high pressure pelitic granulites in the Huai'an complex, North China Craton: Evidence from thermodynamic modeling and isotope geochronology. Regional metamorphism at extreme conditions: Implications for orogeny at convergent plate margins. Chakrabarti, in Geology of the Himalayan Belt, 2016. Prograde and retrograde reactions, garnet zoning patterns, and accessory phase behaviour in SW Finland migmatites, with implications for geochronology. Age, Correlation, and Provenance of the Neoproterozoic Skelton Group, Antarctica: Grenville Age Detritus on the Margin of East Antarctica. However, muscovite is coarse grained and cuts across the schistosity and was possibly formed during the cooling phase. 4.3. Tyler, in Encyclopedia of Geology, 2005. P.G. Protolith lithostratigraphy of the Greater Himalayan Series in Langtang, Nepal: implications for the architecture of the northern Indian margin. This proposal is supported by the recently obtained U–Pb zircon data from the EGMB-south, which preserves a record of a prolonged accretionary process that started in the arc-continent collision and culminated in the continent–continent collision (Pacific-type) during c. 1850–1600 Ma (Vijaya Kumar, Ernst, Leelanandam, Wooden, & Groves, 2009). (2002) made a division of this sequence into two segments with a thrust in between, the Kaghtang Thrust. Fig. 20 C) consistent with granulite facies metamorphism occurring contemporaneously with eclogite facies meta-morphism along strike to the northeast. Single zircon ages of migmatitic gneisses and granulites in the Obudu Plateau: Timing of granulite-facies metamorphism in southeastern Nigeria. naceous facies in the east and calcareous facies in the west (Heron, 1953; Sen, 1981). Lithoprobe—parameters, processes, and the evolution of a continent Reference Module in Earth Systems and Environmental Sciences. Tectonic setting is Arc collision. Therefore, it is abundantly evident from the available geochronological data that the EGMB must have been affected by the Neoproterozoic-Cambrian events indicating that the EGMB was juxtaposed against east Antarctica during Gondwana assembly. The so-commonly observed high T, low P phase (M2) at the high levels of the HHC, according to them, might have an initial stage of higher T and P. Pecher and Le Fort (1986) incorporated the work of Gansser (1983) in their metamorphic map of Central Himalaya (see Fig. Granulite is a high-grade metamorphic rock containing granular minerals, typically red garnet mixed with grains of pyroxene, quartz, and feldspars formed under great heat without melting. Felsic and bimodal volcanics and interlayered metasedimentary rocks of the Myola Volcanics and the Broadview Schist, and the Peake Metamorphics were deposited on the Gawler Craton ∼1790 Ma, contemporaneous with syntectonic granitic rocks of the Lincoln Complex. Number of times cited according to CrossRef: Deep infiltration of surface water during deformation? Mineral assemblages and microstructures indicate that these rocks were affected by granulite-facies metamorphism and anatexis followed by decompression and cooling. Rb depletion in biotites and whole rocks across an amphibolite to granulite facies transition zone, Tamil Nadu, South India. The full text of this article hosted at iucr.org is unavailable due to technical difficulties. The most common mineral assemblage of granulite facies consists of antiperthitic plagioclase, alkali feldspar containing up to 50% albite and Al 2 O 3-rich pyroxenes. Large‐scale melt‐depletion in granulite terranes: an example from the Archean Ashuanipi Subprovince of Quebec. (1989): The origins of granulites: a metamorphic perspective. In mafic rocks, the greenschist–amphibolite facies transition is designated by the appearance of hornblende and Ca-rich plagioclase and the disappearance of actinolite and Na-rich plagioclase. Granulite facies metapelite, biotite gneiss and metabasic gneiss in Namaqualand contain coarse‐grained, discordant, unfoliated, anhydrous segregations, surrounded by a finer grained, foliated matrix that commonly includes hydrous minerals. Nonetheless, direct expulsion of CO2 from crystallizing intrusions could lower aH2O dramatically, promote granulite facies metamorphism and, in some cases, result in graphite precipitation (Farquhar and Chacko, 1991). Thus, the tectonic setting of the eclogite facies was somewhat enigmatic. Local post-and anorogenic events (bimodal magmatism including gabbro–anorthosite and rapakivi–granite intrusions, and high-grade metamorphism) in different places within a reborn Palaeoproterozoic supercontinent developed at various times after termination of the collisional and accretionary processes, generally after 1.7 Ga. The postkinematic mineral assemblages, however, formed at around 640°C and 6 kb. The Lindås Nappe in the Bergen Arcs is composed of granulite facies remnants of Proterozoic lower crust belonging to the former Jotun-Lindås microcontinent (Fig. The creation of the first supercontinent at the end of the Archaean (section 3.2), covering a significant part of the Earth’s surface, must have played an essential role in the reorganisation of the convection cell system in the underlying mantle. Although igneous textures were not observed, the homogeneity, massive nature, and the presence of enclaves within the charnockite gneisses of the NGB indicate an igneous origin for the protoliths. Regionally extensive metamorphic overprints include Devonian and Cretaceous polymetamorphic amphibolite–granulite facies gneisses (formed from Buller, Takaka, Median, and Karamea–Paparoa protoliths). Reassessment of the nature of granulite-facies metamorphism leads to the recognition of the within-plate and plume-related origin of major granulite–gneiss belts. In the Curnamona Craton, the shallow-marine, immature clastic sedimentary rocks and bimodal volcanics of the Willyama Supergroup were deposited between ∼1715 and ∼1645 Ma. Abstract Transactions of the Royal Society of Edinburgh: Earth Sciences. Mafics are subordinate in the rock, and muscovite is conspicuous by its presence in the Sure gneiss. Some Remarks on Melting and Extreme Metamorphism of Crustal Rocks. The size, shape, distribution and modes of segregations suggest only limited migration and extraction of melt. The LSL is positioned at the central region of the HHC, much higher up from the MCT. This metamorphism preserves important records of the tectonic history of orogenic belts and the formation of cratons. The Sure gneiss is reported to be a two-mica granite gneiss, which is locally migmatitic. Features of the amphibolite–granulite facies boundary (line 3, in Figure 5) and the lower limit of the greenschist facies (line 1, in Figure 5) have been briefly discussed. With the recognition that much of the intrusion, metamorphism, and deformation in the Buller and Takaka terranes (‘Tuhua Orogen’) occurred during the Cretaceous (of ‘Rangitata’ age), the orogen terminology became obsolete. Grujic et al. Thermal granulite‐facies metamorphism with diffuse retrogression in Archaean orthogneisses, Fiskefjord, southern West Greenland. Learn about our remote access options, Department of Geology, University of Cape Town, Rondebosch, 7700 South Africa. Fluid-induced Dehydration of the Paleoarchean Sand River Biotite-Hornblende Gneiss, Central Zone, Limpopo Complex, South Africa. Exhumation of the Haast Schist belt was episodic, with most of the schist being at the surface by 105 Ma and deeper levels being exhumed along the Alpine Fault from 20 Ma to the present day. In this paper, we summarize the Proterozoic tectonother- mal evolution of the Broken Hill Block in light of structural, metamorphic and geochronological analysis conducted within a high-temperature shear zone located in the south of the terrane (Forbes et al., 2005, 2007). The amphibolite to granulite facies rocks overlying the MCT occupies a vast expanse of Bhutan and is named the Thimphu Group/Great Himalayan Zone/HHC/Tibetan Slab (Fig. The basal Sure Formation is a sequence of granite gneiss and schists, and is the most widespread amongst the three formations. Grew and Manton (1986) reported 2507 and 2520 Ma age from the study of allanite in pegmatoid veins cutting across amphibolite in the Kabbaldurga Charnockite. The plume-related riftogenic and spreading processes within the continental areas can be attributed to “weak attempts” to disrupt the supercontinent (Mints, 1998). The boundaries between the Zhujiafang … The granulite-facies metamorphism with peak P-T conditions at 718–729 ºC and 0.46–0.53 GPa is characterized by an anticlockwise P-T path. 4.4a). The 90 Ma Kigluaik pluton forms the core of a granulite facies gneiss dome and is The transition from blueschist to eclogite facies (line 7, in Figure 5) is a very gradual boundary. The third phase of the orogeny took place between 1745 and 1690 Ma and involved deformation, medium-grade metamorphism, and further granite intrusion (Figure 4). Phase relations and fluid inclusion evidence indicate greatly reduced water activity (aH2O) in the granulite facies (cf. The final breakup of Columbia at about 1.3–1.2 Ga was immediately followed by the assembly of the supercontinent Rodinia along the globally distributed Grenvillian orogens at 1.0 Ga (Dalziel, 1997). Cordierite as a sensor of fluid conditions in high‐grade metamorphism and crustal anatexis. The Neoarchean and Paleoproterozoic granulite-gneiss complexes of the northern East European Craton, including their tectonic setting, accompanying igneous and sedimentary rocks, character of metamorphism and deep structure are considered in this paper. The reworking of granulite facies rocks of the region was correlated and a possible linkage between both the domains was suggested (Dasgupta & Sengupta, 2003). Timing and conditions of regional metamorphism and crustal shearing in the granulite facies basement of south Namibia: Implications for the crustal evolution of the Namaqualand metamorphic basement in the Mesoproterozoic. Geochemical signatures of metasedimentary rocks of high-pressure granulite facies and their relation with partial melting: Carvalhos Klippe, Southern Brasília Belt, Brazil. Grujic et al. Journal of South American Earth Sciences. Chinese Journal of Geochemistry, vol. This contribution ... and tectonic setting remains unclear. mean1 Median ±1σ 1 Archaean gneisses 95 3000– 2500 Dominantly tona-litic to granitic gneisses Early Proterozoic (c. 2.0–1.8 Ga) amphibo-lite- to granulite-facies metamorphism. The ages of granulite facies metamorphism in the southern part of the Dharwar Protocontinent range between 2500 ± 50 and 2540 ± 17 Ma (Hansen et al., 1997). Petrological studies of metagabbros from the southwest periphery of the Biligirirangan Block reveal clockwise prograde and retrograde metamorphism in a subduction zone setting at a HP of 18–19 kbar and temperature of ~840°C (Ratheesh-Kumar et al., 2016). sent day, different plate tectonic settings exhibit contrasts in heat flow that are registered as differing metamorphic facies series in distinct crustal terranes (Miyashiro, 1961), although how far back in time these relationships are reliable is unclear. Mesoproterozoic granulite and amphibolite facies gneisses of the Musgrave Block were overprinted during the Petermann Orogeny (-550 Ma)with zones of high strain concentrated along broadly east-west trending shear zones. Granulite facies xenoliths from the Yuhuashan complex, central Jiangxi, South China constraints on Late Palaeozoic orogeny and middle-lower crust components Trace element geochemistry and tectonic setting characterization of granulite facies rocks from southwest Obudu Plateau, southeastern Nigeria. The ridges are composed of volcanic mountains that erupt basalt onto the surface of the ocean and by that process create new oceanic crust. Consequently, brines are probably more effective deep crustal transport agents, and have the potential to cause metasomatic effects, including alkali metasomatism and regional rubidium depletion, owing to their high chlorine contents and alkali exchange capacities (cf. 2012; and references therein). P–T Conditions, Mechanism and Timing of the Localized Melting of Metapelites from the Petronella Shear Zone and Relationships with Granite Intrusions in the Southern Marginal Zone of the Limpopo Belt, South Africa. Columbia had a long-lived history of subduction related growth via accretion at important continental margins for nearly 500 Myr and a correlation of major accretionary belts of c. 1760–1700 Ma orogenesis around the preexisting cratons involving Laurentia, Antarctica, South Africa, and Australia including the eastern margin of India was proposed (Zhao, Sun, Wilde, & Li, 2004). granulitic slab suggest emplacement in a brittle extensional setting whereas garnet coronas attest to subsequent burial under high-pressure (HP) granulite facies at relatively high temperature. The Grenvillian Provinces including the EGMB skirting east Antarctica were reworked, truncated and offset by Pan-African mobile belts, there by implying that east Gondwana underwent significant reorganization during the Cambrian, unlike in many models where it was assumed to have stabilized during the late Mesoproterozoic (Fitzsimons, 2000). 28(3), pp. Geochemical signatures of mid-crustal melting processes and heat production in a hot orogen: The Kerala Khondalite Belt, Southern India. See also Palin et al. Orthopyroxene‐bearing, mafic migmatites at Cone Peak, California: evidence for the formation of migmatitic granulites by anatexis in an open system. Department of Earth Sciences, University of Cambridge, Downing Street, Rondebosch, 7700 South Africa. Evidence from a low- δ18O shear zone at Koegel Fontein, Namaqualand, South Africa. In north-central Bhutan northeast of Thimphu, Swapp and Hollister (1991) studied metamorphic textures and assemblages in the higher levels of the HHC (Tibetan Slab), which they divided into a Lower Structural Level (LSL) and a Higher Structural Level (HSL) zone. The boundaries between facies (and corresponding areas on the tempera… The segregations have modes consistent with the hypothesis that they are the solid and liquid products of the dehydration‐melting reactions: Bt + Sil + Qtz + PI = Grt ° Crd + Kfs + L (metapelite), Bt + Qtz + Pl = Opx + Kfs + L (biotite gneiss), and Hbl + Qtz = Opx + Cpx + Pl + L (metabasic gneiss). Both muscovite and quartz are significantly present in the highest grade. Most metamorphic terranes, especially in the internal parts of continents, are composed of greenschist, amphibolite, and granulite facies rocks, including migmatites at the high metamorphic grades. According to them, the P-T condition of the last equilibration in the HSL was about 630°C and 4 kb. Conditions during the formation of granitic magmas by crustal melting – hot or cold; drenched, damp or dry?. Strain distribution within a km-scale, mid-crustal shear zone: The Kuckaus Mylonite Zone, Namibia. In article View Article [5] Geologiska Föreningen i Stockholm Förhandlingar. Granulite facies amphibole (pargasite) in the olivine gabbro is distinguished from the amphibolite facies amphibole of dykes and gneiss by sodium content that reaches 4.2wt%. Seemingly disparate temperatures recorded in coexisting granulite facies lithologies. The sillimanite–granulite facies rocks contain sillimanite–biotite–garnet–plagioclase–K-feldspar–quartz–cordierite–muscovite–hercynite. Curiously, granulite facies terrains of Brazil are not cited, possibly due to the paucity of published P-T data on Brazilian granu- lites in international journals. 10. (2012) Rocks which contain certain minerals can therefore be linked to certain tectonicsettings, times and places in the geological history of the area. Granulites and charnockites of the Gruf Complex: Evidence for Permian ultra-high temperature metamorphism in the Central Alps. However, the highest grade rocks in sillimanite (±cordierite) zone of Pecher and Le Fort (1986) containing leucogranites were shown by Gansser (1983) under sillimanite–granulite facies. Granulite facies metamorphism in the Mallee Bore area, northern Harts Range: implications for the thermal evolution of the eastern Arunta Inlier, central Australia. We use cookies to help provide and enhance our service and tailor content and ads. On ultrahigh-temperature crustal metamorphism. The Takhsang Formation is composed of garnet–sillimanite–biotite gneiss largely devoid of muscovite (Golani, 1995, p. 96), which, if present, occurs as a second-generation grain. Geological Society, London, Special Publications. In other words, the concept implies a continuity of the Archaean Dharwar rocks further south of the defined boundary. Experimental Study of the Melting Reaction and Genetic Mechanism of Mineral Phase Transformation in Granulite Facies Metamorphism. Anatectic migmatites in medium‐ to low‐pressure granulite facies metasediments exposed in the Larsemann Hills, East Antarctica, contain leucosomes with abundant quartz and plagioclase and minor interstitial K‐feldspar, and assemblages of garnet–cordierite–spinel–ilmenite–sillimanite. The continuity of Peninsular Gneiss into the massive granulite-charnockite ensemble is detected by the presence of relict banding within granulite facies rocks (Fig. The opening of the Mesoproterozoic rift between India and east Antarctica subsequent to the breakup of Columbia may have formed a large oceanic basin between the two where in the sedimentary sequences of the EGMB were deposited (Zhao et al., 2004). 248-257. K. Bucher, in Encyclopedia of Geology, 2005. Palaeoproterozoic tectonic and crust-forming processes were instigated mainly by 2.51–2.44 Ga and 2.0–1.95 Ga mantle plumes of global significance (“superplumes”) (sections 3.2 and 3.3). 4.3), banded iron formation, calc-silicate rocks, quartzites, and amphibolites in the southern part of the Dharwar Protocontinent. Metamorphism and partial melting of high-pressure pelitic granulites from the Qianlishan Complex: Constraints on the tectonic evolution of the Khondalite Belt in the North China Craton. Contradicting the traditional usage, the recent studies help to reinterpret the ‘Fermor Line’ as a metamorphic isograd boundary marking a transition between the upper amphibolite facies and the hypersthene-bearing granulite facies metamorphism in the south (Janardhan, 1983; Srikantappa et al., 2003). Metamorphism probably took place in the deep parts of a Jurassic–Early Cretaceous accretionary wedge. Spatially‐focussed melt formation in aluminous metapelites from Broken Hill, Australia. Fluid composition and propagation in the deep crust: Case studies from the Limpopo Complex, South Africa. Petrology of an intrusion‐related high‐grade migmatite: implications for partial melting of metasedimentary rocks and leucosome‐forming processes. Please check your email for instructions on resetting your password. The lower amphibolite facies rocks contain kyanite–garnet–biotite–muscovite–plagioclase–quartz–staurolite assemblage, and the higher amphibolite facies rocks bear sillimanite–muscovite–garnet–plagioclase–quartz–staurolite assemblage, and the higher amphibolite facies rocks bear sillimanite–muscovite–garnet–plagioclase–quartz ± kyanite ± staurolite ± K-feldspar. timing of the peak and retrograde metamorphism for the granulites, the tectonic position of the HP granulite terrane and tectonic evolution in the eastern Himalayan syntaxis in an attempt to resolve this controversy. In the early 1980s it was realized that the Mesozoic Rangitata Orogeny was probably a composite of an older subduction-related event and a younger extension-related event. Lithology Tectonic setting Tectonometamorphic history Heat-production rate (μW m-3) Area wtd. Concentrated aqueous solutions of strong electrolytes, including (Na,K)Cl, would have low aH2O, as would CO2-rich fluids. (2002) considered the Great Himalayan Sequence (GHS) as a core crustal channel of low-viscosity layer of 10–15 km thickness below the Tibetan plateau and extending for over 200 km. Kyanite occurs in muscovite-rich parts of the schists. Retrograde melt–residue interaction and the formation of near‐anhydrous leucosomes in migmatites. Metamorphic Petrology: Mineralogical, Field, and Tectonic Aspects. Leucogranulites from the Bohemian Massif. Dehydration‐melting reactions, in which water from a hydrous phase enters the melt, leaving an anhydrous solid assemblage, are the dominant mechanism of partial melting of high‐grade rocks in the absence of externally derived vapour. A metamorphic facies is a set of mineral assemblages in metamorphic rocks formed under similar pressures and temperatures. A comparison of observed and thermodynamically predicted phase equilibria and mineral compositions in mafic granulites. If both chlorine and CO2 contents are high, then it is likely that immiscible CO2-rich and chlorine-rich fluids would coexist at high P and T (Duan et al., 1995; Schmidt and Bodnar, 2000), consistent with fluid inclusion evidence for multi-phase granulite facies fluids (Touret, 1985; Crawford and Hollister, 1986). The eclogite zone in the Dabie Shan Complex is sandwiched between amphibolite facies gneiss slices. The hot central and upper portion together were rapidly exhumed during and after the thrusting event. Harald Fritz, Veronika Tenczer, Christoph Hauzenberger, Eckart Wallbrecher, Sospeter Muhongo Hot granulite nappes — Tectonic styles and thermal evolution of the Proterozoic granulite belts in East Africa, Tectonophysics 477, no.3-4 3-4 (Nov 2009): 160-173. When water activity is low, pervasive partial (dry) melting will occur at much higher temperatures and hydrous minerals (muscovite, biotite, and amphibole) may decompose to anhydrous ones by local dehydration melting. Physics and Chemistry of the Earth’s Interior. The main ocean closure was probably some where in ice-covered central East Antarctica within inferred blocks of 1.2–0.8 Ga mafic granitoids. Isotopic constraints on fluid infiltration from an eclogite facies shear zone, Holsenøy, Norway. Mount Isa) during the Proterozoic. An overview of metamorphism in relation to tectonic regimes: In the host Ama Drime orthogneiss, the granulite event is correlated with synkinematic sillimanite-grade metamorphism and muscovite dehydration melting. The fundamental change in the Earth’s history at the Archaean–Palaeoproterozoic boundary was linked to the transition from Archaean “microplate tectonics” to Palaeoproterozoic “supercontinent tectonics” (or “micro-ocean tectonics” having in mind the limited size of the predominantly Red Sea-type oceans that originated within a partially disrupted supercontinent) (sections 3.4 and 3.6). The thermal pulse recorded at c. 1600 Ma in the EGMB-south is similar to the reworking of the NRBF in East Antarctica and may indicate a connection involving the EGMB-south and Napier-Rayner complex at this time (Bose, Dunkley, Dasgupta, Das, & Arim, 2011). Ma c dykes as monitors of hp granulite facies metamorphism in the Grenville front tectonic zone (western Quebec). The metapelite-dominated schist horizon overlying the Sure Formation is named the Naspe Formation (Paro Formation of Gansser, 1983), which consists of a thick interlayered sequence of kyanite–staurolite–garnet–mica schist, commonly graphitic, along with dolomite (Golani, 1995). A. Feenstra, G. Franz, in Reference Module in Earth Systems and Environmental Sciences, 2015. Another possible aspect in such comparisons is with regard to the source rocks for the sedimentary protoliths of EGMB-south. In the Gawler Craton, Archaean gneissic rocks of the Sleaford and Mulgathing complexes were deformed, metamorphosed to, Reference Module in Earth Systems and Environmental Sciences, Most metamorphic terranes, especially in the internal parts of continents, are composed of greenschist, amphibolite, and.

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