 | | Journal (article/letter/editorial) | | scapolite-wollastonite calc-silicates from East Antarctica: the application and limitations of activity-corrected...of the northern Prince Charles Mountains, East Antarctica, preserve a number of reaction textures including...from the northern Prince Charles Mountains, East Antarctica, to show that interpretations made using such...Land are part of the Proterozoic Complex of East Antarctica (Fig. la) which comprises granulite facies mineral...Archaean cratons and the Proterozoic Complex in East Antarctica between 50 and 70"E. NC, Napier Complex; NPCM |  | | Journal (article/letter/editorial) | | Australia, and the Northern Prince Charles Mountains, Antarctica, are consistent with cooling without fluid influx...reaction products. In the case of the Rauer Group, Antarctica, near-isothermal decompression from ca. 8 to...in calc-silicates from granulite terranes in Antarctica and central Australia are then described and...restricted compositional group between mizzonite and meionite. Substitution for C a C O 3 may range up to 10...exceeds 4 mol% in the examples considered here. Meionite contents calculated as equivalent anorthite based |  | | Journal (article/letter/editorial) | | recently published on calc-silicate granulites from Antarctica, Australia and Italy (Schenk 1984; Warren et...of other parts of Eastern Ghats and parts of Antarctica is presented in Fig. 5, which shows a distinct...assemblage with meionite component varying from 74 to 95, whereas in Gr. II and III, meionite component is...This meionite content of scapolite is similar to that reported from Rauer group of East Antarctica (Harley...reaction probably occured during peak P-¹ condition meionite#4wollastonite#calcite"3grossular#quartz#2CO 2 |  | | Journal (article/letter/editorial) | | in Precambrian granulites from Australia and Antarctica calc-silicate R.G. WARREN, Bureau of Mineral...rock from the granulite terrain of Enderby Land, Antarctica, contains scapolite, wollastonite, calcite, diopside...Zo = diopside garnet gehlenite = grossular = meionite = plagioclase = quartz = scapolite = vapour =...Calc-silicate rocks from McLeod Nunataks, Enderby Land, Antarctica, also contain wollastonite and scapolite (Sheraton...Milton locality consists of diopside, scapolite (meionite, approx. [AnWAbl&. CaC03, see Table 2), calcite |  | | Journal (article/letter/editorial) | | of Cl-rich scapolite boudins in Skallen, East Antarctica: evidence for changing fluid condition in the...crust exposed in the Lützow–Holm Complex, East Antarctica, provide insights into the changing fluid composition...rims in contact with biotite or clinopyroxene are meionite rich. Fine-grained recrystallized equigranular...end-member Na3Al3Si9O24ÆCaCO3; meionite, Ca3Al6Si6O24ÆCaCO3; and sulphate meionite, Ca3Al6Si6O24ÆCaSO4 (Evans...composition in deep crustal rocks from Skallen, East Antarctica. Based on reaction textures, mineral chemistry |  | | Journal (article/letter/editorial) | | Pressure-Temperature-Fluid Histories: The Rauer Group, East Antarctica by SIMON L. HARLEY 1 AND IAN S. BUICK 2 * 1 ...fades calc-silicates from the Rauer Group, East Antarctica, contain grossular-wollastonite-scapolite-clinopyroxene...SETTING AND BACKGROUND The Rauer Group, East Antarctica (Fig. 1), is an orthogneiss-dominated granulite...generalized geology of the Rauer Group, Prydz Bay, East Antarctica, showing the distribution of calc-silicate boudins...north. Inset: location of main map area in East Antarctica. D, Davis Station; M, Mawson Station; N, Archaean |  | | Journal (article/letter/editorial) | | Scapolite in all three associations is rich in meionite (Table 4). The EqAn [= lOo(Al - 3)/3] of scapolites...of the type wollastonite + andradite + CaTs + meionite = hedenbergite + calcite + grossular + 0,. ...calcite + quartz = wollastonite + C 0 2 , (a) + meionite calcite + wollastonite = grossular + COz. (b)...disorder in meionite resulting in drastic changes in reaction gradients and a-X relations in meionite (Moecher...Gibbs free energy and to model mixing relations in meionite for scapolite-bearing equilibria. Subsequently |  | | Journal (article/letter/editorial) | | granulites from the Bolingen Islands, Prydz Bay, East-Antarctica: implications for the retrograde P-T path Y ...granulites from the Bolingen Islands, Prydz Bay, East Antarctica, exhibit a sequence of reaction textures that...inclusions in cordierite. + + + Key words: Antarctica; Bolingen Islands, Prydz Bay; calc-silicates;...approximately 120 km west of the Vestfold Hills in East Antarctica (Fig. l), and are part of a high-grade metamorphic...Islands and surrounding areas in Prydz Bay, East Antarctica. Areas in black are outcrops not covered by ice |  | | Journal (article/letter/editorial) | | temperature stability of the scapolite end member meionite relative to the reactant phases. Scapolite is...plagioclase and calcite; 3Anorthite + Calcite = Meionite (2) With increasing temperature most mineral...Essene, 1990; Harley and Buick, 1992) indicate meionite is stabilized relative to its component phases...the need to assign a configurational entropy to meionite corresponding to complete AI-Si disorder in order...completely disordered standard state for meionite, the meionite component in natural scapolite solid solutions |  | | Journal (article/letter/editorial) | | calcsilicate granulites stabilization of nearly pure meionite and of the wollastonite-plagioclase-andradite-rich...facies terrains of the world (Napier Complex, East Antarctica-Ellis 1980, 1983; Harley 1985; Labwor Hill, Uganda-Sandiford...textures are listed in Table 1. At Borra, nearly pure meionite (Eq An = 95) broke down to a symplectite of anorthite...anorthite and calcite according to the reaction Meionite = anorthite + calcite This reaction with near-zero...An, Anorthite; Cc, calcite; Gr, grossular; Me, meionite; Qz, quartz; Sc, scapolite; and Wol, wollastonite |  | | Journal (article/letter/editorial) | | 99.76 99.02 Si Ti Al Fe Mn Mg Ca Na K Total %Meionite Eq An XAn Cations on the basis of Si q Al s 13...relation of Oterdoom and Gunter Ž1983. were used for meionite and that of Aranovich and Podlesskii Ž1989. were...Ž XAn s 0.99.. In assemblage A the activity of meionite in scapolite is 0.79 " 0.02 ŽEq An s 85., whereas...grossular-absent assemblage B the activity of meionite is only 0.55 " 0.03 ŽEq An s 76.. These ac- 93...Grs—grossular, An—anorthite, Wo–wollastonite, Mei–meionite, Cal–calcite and Qtz —quartz. 94 M. Satish-Kumar |  | | Journal (article/letter/editorial) | | granulite facies gneisses in MacRobertson Land, east Antarctica, and preserve evidence of ductile non-coaxial...is dependent on it remaining dry. Key words: Antarctica; geobarometry; geothermometry; granulite; P-T...of rock exposures in MacRobcrtson Land, east Antarctica. Fe.2. increase of u)o-4oo"C above the temperatures...from near Mawson Base, MacRobertson Land, east Antarctica (Fig. l), which cut Mawson Charnockite and xenoliths...poor in neoblastic clinopyroxene. Scapolite is meionite-rich [Eq. 1- (Si-6)/3] and garnet is a grossular-rich |  | | Journal (article/letter/editorial) | | This includes an evaluation of Al-Si disorder in meionite, as this has the greatest effect on derived phase...phase relations. Available experimental data on meionite stability, X-ray diffraction refinements and nuclear...constrain the Al-Si ordering state of synthetic meionite. However, the data are most consistent with a...to calculate P-T and T-X^^ equilibria involving meionite in the CaO-Al 2 O 3 -SiO 2 -CO 2 -H 2 O (CASCH)...disordered standard state for meionite. The Gibbs free energy of meionite was calculated from reversals |  | | Journal (article/letter/editorial) | | CaoAluSi.OroCO. morthite (An) in plagioclase (l) meionite (Me) in spotite calcite with NaSi(CaAI)-, substitution...Baker reagentprecipitated calcite, and synthetic meionite and plagioclasesof composition An,ooand Anrr....scapolite structure. An activity model for the meionite component in terms of its mole fraction, Xr",...calcium carbon- composition closer to the meionite and sulfate meionite (Me); a so- end-members,with many scapolitegrains...scapolitegrains having closeto ate end-member,meionite, CaoAluSiuOroCO, dium chloride end-member, marialite |  | Gallien, Florian, Mogessie, Aberra, Bjerg, Ernesto, Delpino, Sergio, Castro de Machuca, Brigida (2009) Contrasting fluid evolution of granulite-facies marbles: implications for a high-T intermediate-P terrain in the Famatinian Range, San-Juan, Argentina. Mineralogy and Petrology, 95 (1) 135-157 doi:10.1007/s00710-008-0026-1 | Journal (article/letter/editorial) | | Scapolitewollastonite calc-silicate granulites from East Antarctica have been studied by Motoyoshi et al. (1991)...Scapolite (Table 2) is a solid solution between meionite (Ca4Al6Si6O24CO3) and mizzonite (NaCa3Al5Si7O24CO3)...with minor variations in Na2O, Cl and SO3. The meionite content ranges between 75 mol% and 80 mol%. Equivalent...electron microprobe analyses of scapolite. Calculated meionite activities are also given Sample B06-18 1 Rim...X-meionit 0.76 0.75 0.76 eqAn 0.68 0.66 0.68 a-meionite 0.25 0.23 0.25 XCl 0.06 0.08 0.03 0.02 0.03 0 |  | | Journal (article/letter/editorial) | | (anhydrous) end-members marialite (Ma) Na,Al&O,,Cl and meionite (Me) Ca,Al,Si,O,,CO,. Intermediate members do...marialite (15 < Me < SO), sodian meionite (50 < Me < 65) and meionite (Me 65-100). A large number of scapolite...formulae of marialite (Ma) Na,Al,Si,O,,Cl and meionite (Me) Ca,Al,Si,O,,CO,? Are proportions of Na-Ca...(or An, - CaCO,). Marialite (Ca/4 < 0.5) a n d meionite (Ca/4 2 0.5) are the only two currently accepted...Along Ca-richer portions of the series joining to meionite, Evans et al. (1969) suggested that if the only |  | | Journal (article/letter/editorial) | | compositional zoning in scapolite, Skallen, East Antarctica. Research Expedition −39. The rock types of...continental crustal evolution. Holm Bay, East Antarctica（Fig. 1）during the Japanese Antarctic Fig. 1...distinct compositional zoning with marialite core and meionite rim. References Osanai, Y., Toyoshima, T., Owada...Shiraishi, K., 2004, Geological map of Skallen, East Antarctica（Revised version） Antarctic Geol. Map. Ser., Sheet...microfractures in calcite from a marble from East Antarctica: Evidence from gigantic（21 ‰）oxygen isotopic |  | | Journal (article/letter/editorial) | | (Al − 3)/3 = 0.71–0.81, Table 2a) with maximum meionite content found in Association II (EqAn up to 0...wollastonite can be explained by the reaction: Meionite + 5wollastonite → 3grossular + 2quartz + CO2 (Cal...reactions: Wollastonite + 3CaTs + 2quartz + CO2 → meionite (8) CaTs + quartz → anorthite (9) Drop in...be explained by the reaction: 3Wollastonite + meionite + 2calcite → 3grossular + 3CO2 (An, Qtz) (10)...scapolite-forming reaction: Wollastonite + anorthite + CO2 → meionite + quartz(Cal, Grs) (11) Lack of sufficient quartz |  | | Journal (article/letter/editorial) | | Glacier, northern Prince Charles Mountains, East Antarctica N. C. N. STEPHENSON AND N. D. J. C OOK* Department...Glacier, northern Prince Charles Mountains, East Antarctica, contain prograde metamorphic assemblages comprising...which are common throughout the area. Key words: Antarctica; calcsilicate rocks; granulites; Prince Charles...in the northern Prince Charles Mountains, East Antarctica. They are used to infer the peak metamorphic...compositions are expressed in Table 5 as per cent meionite endmember [Me= 100Ca/(Ca+Na+K)] and equivalent |  | | Journal (article/letter/editorial) | | from West Ongul Island, Lfitzow-Holm Bay, East Antarctica KANENORI SUWA, MASAKI ENAMI ANDTATSUROHORIUCHI...on West Ongul Island, Lfitzow-Holm Bay, East Antarctica. The amphibolite lens and hornblende gneiss were...calcic amphiboles, hastingsite, West Ongul Island, Antarctica. Introduction LARGE concentrations of C1 in...hastingsite are shown in Table 5. The average meionite molecules of the primary scapolite in the calcareous...occurs in the rim of the plagioclase grains. The meionite molecule of secondary scapolite averages 39.1% |  | | Journal (article/letter/editorial) | | paragneissesfrom Little Italy Island, Rauer Group, east Antarctica underwent granulite-facies metamorphism (P :...adjacent pelitic gneissesfrom the Rauer Group, Antarctica. We propose that diffusion of carbon isotopes...granulite-facies orthogneiss-dominatedterrain in east Antarctica (e.g., Harley 1987, 1988; Harley and Fitzsimons1991...reactions between anorthite, calcite, grossular,meionite, quartz,and wollastonitefor fluid-presentassemblages...reactions between anorthite, calcite, grossular, meionite, qtrrtz, and wollastonite for fluid-present assemblages |  | | Journal (article/letter/editorial) | | marbles and calcsilicates of Dronning Maud Land, Antarctica: new data for Gondwana reconstructions S . P...calcsilicates in Central Dronning Maud Land (CDML), East Antarctica. The paleogeographic positioning of CDML as part...bearings on theories concerning the position of East Antarctica in the Gondwana supercontinent. The samples for...Fuhrmann & Lindsley (1988). For the activity of meionite, two different models were tested, namely those...(1990, 1991) derived the Gibbs free energy of meionite from experimental data at 790–815 °C and at pressures |  | | Journal (article/letter/editorial) | | (4),2r 123-135 (1896)' ON THE MINERALOGY OF ANTARCTICA DuNc.qN SrnwAnt, Jr.., Corleton College,Northf'eld...Christensen(Christensen-Vulkan)of Robert' son Island, West Antarctica. The following is a list of the 167 mineral species'subspecies...questionable occurrence, that have been reported from Antarctica. A number of these have been determined only...Leucoxene Limonite Magnetite Malachite Malacolite Meionite Mesolite Microcline Microperthite Mirabilite...petrography. II. Rocks from Ingrid Christensens Land, Antarctica. Sci. Res. Norwegian Antarctic Exped'. 1927-1928 |  | | Journal (article/letter/editorial) | | in computing anorthite activity in plagioclase. Meionite thermometry (Oterdoom & Gunter, 1983) indicates...kbar using reduced activities of anorthite and meionite from mineral chemical analysis (cf. Tables 2,...abbreviations are An – anorthite, Cal – calcite, Mei – meionite, Qtz – quartz, Wo – wollastonite, V – vapour....an aCO2 of 0.85 at 4 kbar (Fig. 4). Thus, the meionite– quartz symplectites may result from near isothermal... The peak temperature was constrained using a meionite thermometer. Retrograde carbonic influx has incremented |  | | Journal (article/letter/editorial) | | granulites in Tonagh Island, Napier Complex, East Antarctica record peak metamorphic pressure − temperature...fragments including the Napier Complex in East Antarctica (e.g., Harley and Motoyoshi, 2000), Eastern Ghats...(Napier Complex, East Antarctica) The Napier Complex of Enderby Land in East Antarctica, a fragment of the...Eastern Ghats Belt is juxtaposed against East Antarctica, and there are a number of reports on sapphirine...This textural association suggests the reaction: meionite + anorthite + diopside = garnet + quartz. Thermodynamic |
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