Hostname: page-component-76fb5796d-skm99 Total loading time: 0 Render date: 2024-04-25T17:27:29.569Z Has data issue: false hasContentIssue false
  • English
  • Français

Wollastonite-bearing assemblages from the Dalradian at Fraserburgh, northeast Scotland and their bearing on the emplacement of garnetiferous granitoid sheets

Published online by Cambridge University Press:  05 July 2018

T. E. Johnson ,
N. F. C. Hudson  and
G. T. R. Droop
T. E. Johnson*
Affiliation:
Division of Earth Sciences, University of Derby, Kedleston Road, Derby DE22 1GB, UK
N. F. C. Hudson
Affiliation:
Division of Earth Sciences, University of Derby, Kedleston Road, Derby DE22 1GB, UK
G. T. R. Droop
Affiliation:
Department of Earth Sciences, University of Manchester, Oxford Road, Manchester M13 9PL, UK
*
*E-mail: timothy.johnson@kfunigraz.ac.at
Get access Rights & Permissions [Opens in a new window]

Abstract

Metasediments of the Tayvallich Subgroup of the Dalradian at Kinnairds Head, Fraserburgh are metamorphosed to sillimanite + K-feldspar grade and form part of the classic high-T low-P Buchan metamorphic terrain. Pelitic samples constrain peak-metamorphic conditions to 615±13°C and 2.2±0.2 kbar. At or close to the metamorphic peak, irregular garnetiferous aplites and autopegmatite bodies intruded the metasediments. Thin marble bands within the sequence are dominated by calcite with diopside, and equilibrated with relatively CO2-rich, internally buffered fluids. Where these are in close proximity to granitoid pegmatites, wollastonite dominates the matrix, and fractures and veins running through the rock contain concentrations of grossular and vesuvianite. With increasing distance from the pegmatite, vesuvianite and then grossular disappear, and wollastonite is only patchily developed. Such occurrences require a flushing of the marble by metasomatic (siliceous and aluminous) aqueous fluids which were derived from the de-watering of the adjacent pegmatite as it crystallized. The large quantities of dissolved silica led to pervasive wollastonite formation for several metres. The smaller quantities of Al reacted to form Ca-Al-silicates which were confined to the fractures.

Keywords

wollastoniteDalradiangranitoidScotland
Type
Research Article
Information
Mineralogical Magazine , Volume 64 , Issue 6 , December 2000 , pp. 1165 - 1176
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2000

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Footnotes

†

Present address: Institute of Mineralogy and Petrology, University of Graz, Univ. Pl. 2, A-8010 Graz, Austria

References

Ahmed-Said, Y. and Leake, B.E. (1996) The conditions of formation of a grossular-wollastonite-vesuvianite skarn from the Omey Granite, Connemara, western Ireland, with special reference to the chemistry of vesuvianite. Mineral. Mag., 60, 541–50.CrossRefGoogle Scholar
Ashworth, J.R. (1976) Petrogenesis of migmatites from the Huntly-Portsoy area, north-east Scotland. Mineral. Mag., 40, 661–82.CrossRefGoogle Scholar
Dempster, T.J. (1985) Uplift patterns and orogenic evolution in the Scottish Dalradian. J. Geol. Soc., 142, 111–28.CrossRefGoogle Scholar
Droop, G.T.R. (1987) A general equation for estimating Fe3+ concentrations in ferromagnesian silicates and oxides using stoichiometric criteria. Mineral. Mag., 51, 431–35.CrossRefGoogle Scholar
Droop, G.T.R. and Al-Filali, I.Y. (1996) Interaction of aqueous fluids with calcareous metasediments during high-T, low-P regional metamorphism in the Qadda area, southern Arabian Shield. J. Metam. Geol., 14, 613–34.CrossRefGoogle Scholar
Goldschmidt, V.M. (1911) Die Kontaktmetamorphose in Kristianiagebiet, Kristiania. Videnskabelig Skrifter I. Mathematisk Naturv. Klasee, No. 11.Google Scholar
Goldschmidt, V.M. (1912) Die Gesetze der Gesteinmetamorphose, mit Beispielen aus der Geologie des südlichen Norwegens. Videnskabelig Skrifter I. Mathematisk Naturv. Klasee, No. 22.Google Scholar
Greenwood, H.J. (1962) Metamorphic reactions involving two volatile components. Carnegie Institute of Washington Year Book, 61, 82–5.Google Scholar
Greenwood, H.J. (1967) Wollastonite: stability in H2O-CO2 mixtures and occurrence in a contact-metamorphic aureole near Salmo, British Columbia, Canada. Amer. Mineral, 52, 1669–80.Google Scholar
Harte, B. and Hudson, N.F.C. (1979) Pelite facies series and the temperatures and pressures of Dalradian metamorphism in E. Scotland. Pp. 323–38 in: The Caledonides of the British Isles – reviewed. (Harris, A.L., Holland, C.H. and Leake, B.E., editors). Geological Society of London Spec. Publ., 8.CrossRefGoogle Scholar
Holdaway, M.J. and Mukhopadhyay, B. (1993) A reevaluation of the stability relations of andalusite: Thermochemical data and phase diagram for the aluminium silicates. Amer. Mineral., 78, 298-315.Google Scholar
Holland, T.J.B. and Powell, R. (1990) An enlarged and updated internally consistent thermodynamic dataset with uncertainties and correlations: the system Na2O-K2O-CaO-MgO-MnO-FeO-Fe2O3-Al2O3-SiO2-TiO2-C-H2-O2 . J. Metam. Geol., 8, 89-124.CrossRefGoogle Scholar
Holland, T.J.B. and Powell, R. (1992) Plagioclase feldspars – activity-composition relations based upon Darken Quadratic Formalism and Landau Theory. Amer. Mineral., 77, 53-61.Google Scholar
Holland, T.J.B. and Powell, R. (1998) An internally consistent thermodynamic data set for phases of petrological interest. J. Metam. Geol., 16, 309–43.CrossRefGoogle Scholar
Hudson, N.F.C. (1980) Regional metamorphism of some Dalradian pelites in the Buchan area, N.E. Scotland. Contrib. Mineral. Petrol., 73, 39-51.CrossRefGoogle Scholar
Johnson, T.E. (1999) Partial-melting in Dalradian pelitic migmatites from the Fraserburgh-Inzie Head area of Buchan, northeast Scotland. PhD thesis, Univ. Derby, UK.Google Scholar
Kerrick, D.M., Crawford, K.E. and Randazzo, A.F. (1973) Metamorphism of calcareous rocks in three roof pendants in the Sierra Nevada, California. J. Petrol., 14, 303–25.CrossRefGoogle Scholar
Kneller, B.C. (1987 a) A geological history of north-east Scotland. Pp. 1-50 in: Geology of the Aberdeen area (Trewin, N.H., Kneller, B.C. and Gillen, C., editors). Scottish Academic Press, Edinburgh Google Scholar
Kneller, B.C. (1987 b) Dalradian of Fraserburgh. Pp. 99-105 in: Geology of the Aberdeen area (Trewin, N.H., Kneller, B.C. and Gillen, C., editors). Scottish Academic Press, Edinburgh.Google Scholar
Powell, R. and Holland, T.J.B. (1988) An internally consistent dataset with uncertainties and correlations: 3. Applications to geobarometry, worked examples and a computer program. J. Metam. Geol., 6, 173-204.CrossRefGoogle Scholar
Read, H.H. (1923) The geology of the country around Banff, Huntly and Turiff. Mem. Geol. Surv. Scotland. Google Scholar
Read, H.H. and Farquhar, O.C. (1956) The Buchan anticline of the Banff nappe of Dalradian rocks in north-east Scotland. Q. J. Geol. Soc. Lond., 72, 131–56.CrossRefGoogle Scholar
Salje, E. (1986) Heat capacities and entropies of andalusite and sillimanite: The influence of fibrolitization on the phase diagram of the Al2SiO5 polymorphs. Amer. Mineral., 71, 1366–71.Google Scholar
Treagus, J.E. and Roberts, J.L. (1981) The Boyndie Syncline, a D1 structure in the Dalradian of Scotland. Geol. J., 16, 125–35.CrossRefGoogle Scholar
Vidale, R.J. (1974) Vein assemblages and metamorphism in Dutchess County, New York. Bull. Geol. Soc. Amer., 85, 303–6.2.0.CO;2>CrossRefGoogle Scholar
Waldbaum, D.R. and Thompson, J.B. (1969) Mixing properties of sanidine crystalline solutions: IV. Phase diagrams from equation of state. Amer. Mineral., 54, 1274–98.Google Scholar
Wickham, S.M. (1987) Crustal anatexis and granite petrogenesis during low-pressure regional metamorphism. The Trois Seigneurs Massif, Pyrenees, France. J. Petrol., 28, 127–69.CrossRefGoogle Scholar
Yardley, B.W.D. (1983) Quartz veins and devolatilization during metamorphism. J. Geol. Soc., 140, 657–63.CrossRefGoogle Scholar