 | | Journal (article/letter/editorial) | | TOPOGRAPltlCAL EUROPE Norway (Norge) Eiksundsdal, Sunm6re, omphacite, 6L Fen, magnesio-arfvcdsonite, 317. Hasvik, SOrOy...Westphalia, ullmannite, 26. Silberbaeh, Bavaria, omphacite, 6I. Wolf~berg, Harz, gersdorffite, 26; plagionite...Berkshire; Ha#on attd Shabbington Wood, Buckinghamshire; Lower Froyle, Selt)orne, and West Worldham, tlampshire;...lithiophorite, 618. Leverburgh, South Harris, omphacite, 61. Loch Don, Mull, plumbogummite group, 935...plumbogummite group, 935. IRELAND Ballyshannon, Donegal, omphacite, 61. Slieve Gullion, Armagh, alkali feldspar, |  | | Journal (article/letter/editorial) | | from Nové Dvory yielded Sm– Nd ages for garnet–omphacite pairs of 342 ± 9 Ma (Beard et al., 1992). The...weakly foliated and consists mainly of garnet, omphacite, kyanite and quartz with minor amounts of rutile...in diameter) are locally present (Fig. 2a,b). Omphacite and kyanite are present in the matrix and as inclusions...inclusions in garnet (Fig. 2). Omphacite grains are about 0.25 mm in diameter, and kyanite is <0.25 mm...(c) Relatively small garnet grain that includes omphacite (Omp). Kyanite and quartz (Qtz) are present near |  | | Journal (article/letter/editorial) | | plagioclase–spinel in kyanite; and diopside–plagioclase in omphacite. The microfractures are often arranged en echelon...Kayal et al., 1993) are evidence that the present lower crust may fracture. Pseudotachylyte formed at granulite...mineral infill changes in type. From garnet to omphacite, the fracture-fill changes from orthopyroxene...Symplectites after clinopyroxene in upper left and lower right corner. Sample ÅS12/94. Scale bar is 100...with an X ratio between 0.43 and Mg 0.64, which is lower than its garnet host (Table 1). Plagioclase and |  | | Journal (article/letter/editorial) | | Mgy1 Al IVAlVI . yet reported for sapphirine. Omphacite has been completely transformed into clinopyroxeneq...indicates that kyanite and omphacite breakdowns were coupled. The kyanite and omphacite pseudomorphs exchanged...for the omphacite breakdown Ži.e., jadeitess q SiO 2 ™ albite ss .. The kyanite and omphacite pseudomorphs...mobility of the chemical components. The kyanite and omphacite pseudomorphs give information about the P–T path...Corresponding author. E-mail: gg@ccr.jussieu.fr. omphacite breakdown during retrogression of eclogite requires |  | | Journal (article/letter/editorial) | | plagioclase±corundum±spinel after kyanite. Kyanite and omphacite were the main reactants in the formation of sapphirine...eclogitization at 969±14 Ma (Johansson et al., 1998). The lower age limit for the peak metamorphism and the deformation...conspicious tectonic and metamorphic break to overlying lower-grade amphibolite facies rocks in the Western Segment...(Johansson & Möller, 1986), the Moldanubian Zone in Austria (Carswell et al., 1989), the Central Gneiss Belt...symplectite (upper left). Resorbed kyanite (Ky; black, lower right) surrounded by sapphirine+plagioclase symplectite |  | | Journal (article/letter/editorial) | | authors are printed in SMALLCAPITALS,Subjects in lower-case roman, and Localities in italics. The minerals...arsenolamprite, 732. Ala di Stura, Piemonte, Italy, omphacite, 6I. Albite, Nigeria, opt., 37o; natural and synthetic...opt., X-ray, 26. Amos Stream, New Caledonia, omphacite, 6I. Ampamatoa, Madagascar, grandidierite, 6~5...Cornwall, anal., 52o. Asahine, Kanto Mts., Japan, omphacite, 61. Ascension Id., arfvedsonite, 317. Ashcroftine...anal., hour-glass structure in, 472; and see Omphacite. Avelinoite, relation to wardite, 598. Axinite |  | Vrabec, Mirijam, Janák, Marian, Froitzheim, Nikolaus, De Hoog, Jan C.M. (2012) Phase relations during peak metamorphism and decompression of the UHP kyanite eclogites, Pohorje Mountains (Eastern Alps, Slovenia) Lithos, 144. 40-55 doi:10.1016/j.lithos.2012.04.004 | Journal (article/letter/editorial) | | contain a peak metamorphic assemblage of garnet, omphacite, kyanite and phengite. Pyrope-rich garnet is unzoned...supersilicic omphacite contains up to 5 mol% of Ca-Eskola molecule. Breakdown of omphacite during decompression...inclusions in peak-pressure minerals – garnet, omphacite and kyanite – are surrounded by radial fractures...symplectites of diopside + plagioclase + amphibole after omphacite, plagioclase + biotite after phengite and sapphirine+... 1989; Powell, 1985) and the garnet–phengite–omphacite–kyanite–quartz/coesite thermobarometer (Krogh |  | | Journal (article/letter/editorial) | | complete conversion of igneous plagioclase to omphacite. In the evolution following the culmination in...la conversion complète du plagioclase igné en omphacite. Au cours de l’évolution suivant le paroxysme...consistent additions by Meyre et al. (1997) for omphacite (diopside, jadeite and hedenbergite endmembers)...occasional relics of kyanite and very rarely omphacite are preserved. Conditions of high-pressure metamorphism...amphibole ± clinopyroxene + plagioclase replacing omphacite. The rare occurrence of spinel and corundum in |  | | Journal (article/letter/editorial) | | Greece and the approximate boundary between the lower and upper tectonic unit marked by the thrust faults...(1981) subdivided western and central Rhodope into a lower and an upper tectonic unit separated by an approximately...approximately SSE–NNW striking thrust plane. A lower and an upper tectonic unit were recognized also by Mposkos...metamorphic overprint), in rocks close together: the lower and upper tectonic units are characterized by metamorphic...(Fig. 2A). The typical eclogite-facies mineral omphacite was found only as an inclusion in kyanite and |  | | Journal (article/letter/editorial) | | peraluminous granulites from the Gföhl Nappe System, Austria Konstantin Petrakakis1 , Nathalie Schuster-Bourgin2...Vienna, Vienna, Austria of Lithospheric Research, University of Vienna, Vienna, Austria Correspondence:...tectono-metamorphic evolution of the Gföhl Nappe System, Austria. They contain the primary assemblage garnet + Al-rich...Variscan orogen exposed in the Czech Republic and in Austria (see Fig. 1). Over approximately the last 3 decades...granulites) at the steep flanks of Mitterbachgraben. The Gansbach–Kicking road and the GPS coordinates |  | | Journal (article/letter/editorial) | | eclogites have been extensively overprinted by lower pressure assemblages and exhibit a variety of coronitic...high-pressure, plagioclase-free assemblage was garnet q omphacite" kyanite" clinozoisiteq rutile. Compositional...clinopyroxene–plagioclase intergrowths after omphacite; the replacement of kyanite by sapphirine–plagioclase...rims can form during the subsequent unloading to lower crustal levels, and provide information on the shape...intergrown with plagioclase in symplectites after omphacite Sample 419576a 419576a 419576b 419583b 419583c |  | Medaris, L. G., Ghent, E. D., Wang, H. F., Fournelle, J. H., Jelínek, E. (2006) The Spačice eclogite: constraints on the P–T–t history of the Gföhl granulite terrane, Moldanubian Zone, Bohemian Massif. Mineralogy and Petrology, 86 (3) 203-220 doi:10.1007/s00710-005-0095-3 | Journal (article/letter/editorial) | | recrystallization. The eclogite assemblage, garnet þ omphacite þ quartz þ rutile plagioclase, yields an estimate...and omphacite (55%), with small amounts of quartz, rutile, ilmenite, and apatite. Many omphacite grains...are sporadically distributed between and within omphacite grains (Fig. 2). Fig. 2. Photomicrograph of the...polarized light). am amphibole; grt garnet; omp omphacite; pl plagioclase; sympl symplectite. Black grains...of inclusions. am amphibole; ilm ilmenite; omp omphacite; pl plagioclase; qtz quartz; rt rutile; ttn titanite |  | | Journal (article/letter/editorial) | | assemblage garnet + omphacite + kyanite + phengite. A prograde metamorphic evolution from a lower P–T (1.5–1.7...clinopyroxene. Near isothermal decompression of eclogite to lower crustal levels (~0.8–1.0 GPa ) led to formation...basin and platform sediments that now occur in the lower nappes and underlying autochthon (Gee, 1975). These...units in the SNC are dominated by psammites in the lower parts, giving way upwards into more semi-pelitic...ultramafites. The SNC is underlain by lower grade units of the Middle and Lower Allochthons and overthrust by |  | | Journal (article/letter/editorial) | | solid-state reaction between kyanite and coexisting omphacite, sometimes involving garnet or other phases as...and Mabit, kyanite replacement is coupled with omphacite symplectitization, the two phases undergoing bimetasomatism...model, especially those regarding the kyanite-omphacite closed system, the zonality of the kyanite pseudomorphs...embedded in a light grey matrix of symplectite after omphacite, or diablastic amphibole + plagioclase replacing...a diopside-plagioclase symplectite indicating omphacite as the parent phase. Original clinopyroxene, unlike |  | | Journal (article/letter/editorial) | | Zone in Lower Austria and W Moravia present evidence for introduction of segments of the Lower Palaeozoic...peridotite massifs in the Moldanubian Zone of Lower Austria (Becker, 1996). Besides, some metasedimentary...normalized REE pattern. Although the rock shows a lower-pressure overprinting, fine-grained garnet has highly...from Dunkelsteiner Wald granulite, Gföhl unit, Lower Austria (Becker & Altherr, 1992) are also shown. Rock...Dunkelsteiner Wald granulite, Gföhl unit of Lower Austria (Becker & Altherr, 1992). Full data on these |  | | Journal (article/letter/editorial) | | secondary and is a product of reactions at pressures lower than the peak recorded pressure. In contrast to...which form at conditions attainable in the mid to lower levels of normal continental crust, high-pressure...Ca-Tschermaks-rich granulite facies pyroxene from those of lower grade (cf. Lovering & White, 1969). In metapelitic...orthopyroxene is taken to mark the transition to the lower temperature amphibolite facies. In this study, HP...replaced by orthopyroxene as melting occurs. At lower pressures, in the sillimanite field, this marks the |  | Li, Yunshuai, Santosh, M., Zhang, Jianxin, Yu, Shengyao, Peng, Yinbiao (2021) Tracking a continental deep subduction and exhumation from granulitized kyanite eclogites in the South Altyn Tagh, northern Qinghai-Tibet Plateau, China. Lithos, 382. 105954pp. doi:10.1016/j.lithos.2020.105954 | Journal (article/letter/editorial) | | mafic-ultramafic associations at the base of the lower crust, which were subsequently exhumed, forming... 3, 4). Inclusions of rutile, clinopyroxene, omphacite, amphibole, plagioclase and kyanite are wrapped...of residual kyanite; (d) Retrograde texture of omphacite with Na-rich plagioclase; (e) Microtextures of...plagioclase around garnet; (f-g) Inclusions of omphacite, rutile, clinopyroxene, Na-rich plagioclase, amphibole...(Grt2a; Table 1). 5.1.2. Clinopyroxene Original omphacite was only retained as inclusions in a few garnet |  | | Journal (article/letter/editorial) | | 1) comprising parts of Czechoslovakia, Poland, Austria and Germany. The block is truncated to the north-east...similar high grade nappes within the Moldanubian of Austria and Czecho- slovakia. On this basis, and following...granodioritic (Finger et al., 1989) Thaya (in Austria) or Brno (in Czechoslovakia) batholith yielding...now exposed, beneath the MZ, in the Thaya (in Austria) and Svratka (in Czechoslovakia) windows (Schulmann...with the Ramzova overthrust separating it from the lower temperature garnet-staurolite-andalusite schists |  | Medaris, L. G., Beard, B. L., Johnson, C. M., Valley, J. W., Spicuzza, M. J., Jelínek, E., Mísâr, Z. (1995) Garnet pyroxenite and eclogite in the Bohemian Massif: geochemical evidence for Variscan recycling of subducted lithosphere. Geologische Rundschau, 84 (3) 489-505 doi:10.1007/bf00284516 | Journal (article/letter/editorial) | | tectonic insertion of upper mantle slices into the lower parts of the thickened continental crust, accompanied...less than 80, low Cr and Ni contents and contain omphacite (jadeite contents mostly greater than 25 tool...Nov6 Dvory bodies (Beard et al. 1992) and from Austria (Scharbert and Carswell 1983; Carswell and Jamtveit...garnet pyroxenite, with symplectitization of omphacite, kelyphitization of garnet and growth of amphibole...garnet pyroxenite, but average N - M O R B has a lower mg n u m b e r than most Gf0hl eclogite samples |  | Medaris, L. Gordon, Beard, Brian L., Jelínek, Emil (2006) Mantle-Derived, UHP Garnet Pyroxenite and Eclogite in the Moldanubian Gföhl Nappe, Bohemian Massif: A Geochemical Review, New P-T Determinations, and Tectonic Interpretation. International Geology Review, 48 (9) 765-777 doi:10.2747/0020-6814.48.9.765 | Journal (article/letter/editorial) | | with no consistent difference, either higher or lower, from the two. Two versions of the Al-in-Opx geobarometer...Ravna formulation yielding temperatures about 90º lower at 30 kbar (Fig. 6B). The equilibrium position for...temperatures for these samples are appreciably lower than those for garnet peridotite, which may be an...Ma were obtained from garnet pyroxenites at Mitterbachgraben, Níhov, and Bečváry, respectively (Carswell...subduction of the former under the latter (Fig. 8, lower panel). Penetration of Moldanubia to lithospheric |  | BALDWIN, J. A., POWELL, R., WILLIAMS, M. L., GONCALVES, P. (2007) Formation of eclogite, and reaction during exhumation to mid-crustal levels, Snowbird tectonic zone, western Canadian Shield. Journal of Metamorphic Geology, 25 (9) 953-974 doi:10.1111/j.1525-1314.2007.00737.x | Journal (article/letter/editorial) | | granulite terrane, and consists of anastamosing lower crustal high-grade granulite facies rocks (Hanmer...accentuated by, partial melting and melt loss but at lower temperatures (<800 C). Given the ambiguity associated...clinopyroxene are devoid of plagioclase and preserve a lower jadeite content, most probably reflecting re-equilibration...metamorphism were 750 C, and were at least 250 lower than would be required to form ternary feldspar...clinopyroxene; g, garnet; hb, hornblende; ky, kyanite; o, omphacite; opx, orthopyroxene; pl, plagioclase; q, quartz; |  | Medaris, Gordon, Wang, Herb, Jelínek, Emil, Mihaljevič, Martin, Jakeš, Petr (2005) Characteristics and origins of diverse Variscan peridotites in the Gföhl Nappe, Bohemian Massif, Czech Republic. Lithos, 82 (1) 1-23 doi:10.1016/j.lithos.2004.12.004 | Journal (article/letter/editorial) | | Moldanubian zone of the Bohemian Massif, consists of a lower unit of migmatitic, granitic orthogneiss, with subordinate...Type II peridotites are characterized by generally lower Mg#’s than those of Type I, association with abundant...that such bodies are generally situated in the lower level of the nappe complex. Occurrences and mineralogical...Type II-Mg. However, most peridotite samples have lower Mg#’s and are designated as Type II-Fe. In Type...been partly to completely replaced by kelyphite, omphacite in eclogite has been largely replaced by symplectite |  | | Journal (article/letter/editorial) | | F., 1967: Die Eklogite Meidling im Tal und Mitterbachgraben im niederSsterreichischen Moldanubikum s~dlich...eclogites and metagabbros of the ~tztal Alps, Tirol, Austria. Contr. Min. Petr. 28, 42--56. Mottana, A., 1970:...of an eclogite from the type locality (Saualpe, Austria). Contr. Min. Petr. 18, 338--346. Mueller, R. F...of clinopyroxeneplagioclase symplectite from omphacite. N. Jb. Min., Mh., Jg. 1966, 185--189. - - and |  | | Book | | Salzburg Hellbrunnerstr. 34lIII 5020 Salzburg Austria P.A. FLOYD Department of Geology University of...Salzburg Hellbrunnerstr. 34/III 5020 Salzburg Austria H.J. FRANZKE Geologisches Institut Leibnizstr...Graz Austria G. FUCHS Geologische Bundesanstalt Wien Rasumowsky-Gasse 23 - 25 1030Wien Austria P. ...Salzburg Hellbrunnerstrasse 34lIII 5020 Salzburg Austria H. KREUZER Bundesanstalt fUr Geowissenschaften...Geologie und Palaontologie Heinrichstr. 26 8010 Graz Austria Z. MisAR Department of Geology Charles University |  | | Journal (issue) | | countries now co-operating include: AUSTRALIA, AUSTRIA, BELGIUM. BULGARIA, C A N A D A , CZECHOSLOVAKIA...Dept, James Cook University, Townsville QLD 4811 Austria: P R O F . H. G. SCHARBERT, Institut ftir Petrologic...y.); 3) the mafic and ultramafic magmas o f the lower volcanic sequence of the Kuhmo—Suomussalmi greenstonc...mineralizing activity in the St Andreasherg 01 district (southwest H a r z , F e d e r a l Republic o...24(1), 1989. p: 9-13. In the St Andreasberg ore district, S W Harz, at some time between t h main and subsequent |
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