Hostname: page-component-586b7cd67f-2plfb Total loading time: 0 Render date: 2024-11-22T17:10:44.509Z Has data issue: false hasContentIssue false
  • English
  • Français

Cognate gabbroic xenoliths from a tholeiitic subvolcanic sill complex: Implications for fractional crystallization and crustal contamination processes

Published online by Cambridge University Press:  05 July 2018

R. J. Preston  and
B. R. Bell
R. J. Preston
Affiliation:
Department of Geology and Applied Geology, University of Glasgow, Glasgow, Gl2 8QQ, UK
B. R. Bell
Affiliation:
Department of Geology and Applied Geology, University of Glasgow, Glasgow, Gl2 8QQ, UK
Get access Rights & Permissions [Opens in a new window]

Abstract

Intruded into the Palaeogene lava field and underlying Moine (Neoproterozoic) crystalline basement rocks around Loch Scridain, Isle of Mull, Scotland, is a suite of high-level, inclined, xenolithic sheets, ranging in composition from basalt, through andesite and dacite, to rhyolite. These sheets, associated with the Mull central volcano, were emplaced post 55 Ma. As well as numerous crustal xenoliths, the more basic members of the complex contain a diverse suite of ultrabasic and basic xenoliths. Xenolith types include feldspathic peridotite with cumulus olivine, pyroxenite, gabbro with cumulus plagioclase and cumulus clinopyroxene, and pure anorthosite. Mineralogical data, coupled with whole-rock major- and trace-element data from a small number of the xenoliths suggest that the xenoliths represent early-formed cumulates cognate with their host basalts. Sr and Nd isotope data from the xenoliths confirms the cognate origin, and also shows that the basic magmas suffered crustal contamination at an early stage.

Keywords

xenolithfeldspathic peridotitepyroxenitegabbroanorthositefractional crystallizationcrustal contamination
Type
Petrology
Information
Mineralogical Magazine , Volume 61 , Issue 406 , June 1997 , pp. 329 - 349
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1997

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

1

Present address: Department of Geology and Petroleum Geology, Meston Building, King's College, University of Aberdeen, Old Aberdeen, AB24 3UE. Telephone: (01224) 273467 e:mail: j.preston @ abdn.ac.uk

2

SURRC contact: Dr G. Rogers - Isotope Geosciences Unit, Scottish Universities Research & Reactor Centre, East Kilbride, Glasgow, G75 0QF, UK.

References

Anderson, A.T.J. (1984) Probable relations between plagioclase zoning and magma dynamics, Puego Volcano, Guatemala. Amer. Mineral. 69, 660-76.Google Scholar
Arculus, R.J. and Wills, K.J.A. (1980) The petrology of plutonic blocks and inclusions tYom the Lesser Antillies island arc. J. Petrol. 21, 743-99.CrossRefGoogle Scholar
Bailey, E.B., Clough, C.T., Wright, W.B., Richey, J.E. and Wilson, G.V. (1924) Tertiary and Post-Tertiary geology of Mull, Loch Aline, and Oban. Mere. Geol. Surv. Scotland. H.M.S.O., Edinburgh.Google Scholar
Barbero, L., Villaseca, C., Rogers, G. and Brown, P.E. (1995) Geochemical and isotopic disequilibrium in crustal melting: an insight from the anatectic granitoids from Toledo, Spain. J. Geophys. Res., 100(B8), 15745-65.CrossRefGoogle Scholar
Bell, B.R. and Claydon, R.V. (1992) The cumulus and post-cumulus evolution of chrome-spinels in ultrabasic intrusions: Evidence from the Cuillin Igneous Complex, Isle of Skye, Scotland. Contrib. Mineral. Petrol. 112, 242-53.CrossRefGoogle Scholar
Bell, B.R., Claydon, R.V. and Rogers, G. (1994) The petrology and geochemistry of cone-sheets from the Cuillin Igneous Complex, Isle of Skye: Evidence for combined assimilation and fractional crystallization during lithospheric extension. J. Petrol. 35, 1055-94.CrossRefGoogle Scholar
Binns, R. A. (1969) High-pressure megacrysts in basaltic lavas near Armidale, New South Wales. Amer. J. Sci., 267-A, 33–49.Google Scholar
Binns, R.A., Duggan, M.B. and Wilkinson, J.F.G. (1970) High pressure megacrysts in alkaline lavas from north-eastern New South Wales. Amer. J. Sci. 269, 132-68.CrossRefGoogle Scholar
Bott, M.H.P. and Tandrigoda, T.A. (1987) Interpretation of the gravity and magnetic anomalies over the Mull Tertiary intrusive complex, NW Scotland∼. J. Geol. Soc., London 91, 17–28.CrossRefGoogle Scholar
Brown, G.M. (1956) The layered ultrabasic rocks of Rhum, Inner Hebrides. Phil. Trans. Roy. Soc. London, B2A0, 1–53.Google Scholar
Brown, G.M. (1957) Pyroxenes from the early and middle stages of fractionation of the Skaergaard intrusion, East Greenland. Mineral. Mag. 31, 511-43.Google Scholar
Brown, G.M. and Vincent, E.A. (1963) Pyroxenes from the late stages of fractionation of the Skaergaard intrusion, East Greenland. J. Petrol. 4, 175-97.CrossRefGoogle Scholar
Cameron, E.N. (1975) Postcumulus and subsolidus equilibration of chromite and coexisting silicates in the Eastern Bushveld Complex. Geochim. Cosmochim. Acta 39, 1021-33.CrossRefGoogle Scholar
Cigolini, C. and Kudo, A.M. (1987) Xenoliths in recent basaltic andesite flows from Arenal Volcano, Costa Rica: Inference on the composition of the lower crust. Contrib. Mineral. Petrol. 96, 381-90.CrossRefGoogle Scholar
Claydon, R.V. (1990) A petrological study of mafic hypabyssal and ultramafic plutonic rocks of the Cuillin Igneous Complex, Isle of Skye, Scotland. Unpublished PhD thesis, University of Glasgow.Google Scholar
Claydon, R.V. and Bell, B.R. (1992) The structure and petrology of ultrabasic rocks in the southern part of the Cuillin Igneous Complex, Isle of Skye. Trans. Roy. Soc. Edinburgh 83, 635-53.CrossRefGoogle Scholar
Conrad, W.K. and Kay, R.W. (1984) Ultramafic and mafic inclusions from Adak Island: Crystallization history, and implications for the nature of primary magmas and crustal evolution in the Aleutian Arc. J.. Petrol. 25, 88–125.CrossRefGoogle Scholar
DeLong, S.E., Hodges, F.N. and Arculus, R.J. (1975) Ultramafic and mafic inclusions, Kanga Island, Alaska, and the occurrence of alkaline rocks in island arcs. J. Geol. 83, 721-36.CrossRefGoogle Scholar
DePaolo, D.J. (1981) Trace element and isotopic effects of combined wallrock assimilation and fractional crystallization. Earth Planet. Sci. Lett. 53, 189–202.CrossRefGoogle Scholar
Dickin, A.P., Jones, N.W., Thirlwall, M.F. and Thompson, R.N. (1987) A Ce/Nd isotope study of crustal contamination processes affecting Palaeocene magmas in Skye, Northwest Scotland. Contrib. Mineral. Petrol. 96, 455-64.CrossRefGoogle Scholar
Donaldson, C.H. (1977) Petrology of anorthite-bearing gabbroic anorthosite dykes in north-west Skye. J.. Petrol. 18, 595–620.CrossRefGoogle Scholar
Duke, J.M. (1976) Distribution of the period four transition elements among olivine, calcic clinopyroxene and mafic silicate liquids: Experimental results. J. Petrol. 17, 499–521.CrossRefGoogle Scholar
Dunham, A.C. and Wilkinson, F.C.F. (1985) Sulphide droplets and the Unit 11/12 chromite band, Rhum: A mineralogical study. Geol. Mag. 122, 539-48.CrossRefGoogle Scholar
Emeleus, C.H. (1987) The Rhum layered complex, Inner Hebrides, Scotland. In: Parsons, I. (ed.) Origins qf Igneous Layering, Reidel Publishing, Dortrecht, 263-86.CrossRefGoogle Scholar
Esson, J., Dunham, A.C. and Thompson, R.N. (1975) Low alkali, high calcium olivine tholeiite lavas from the Isle of Skye, Scotland. J. Petrol. 16, 488-97.CrossRefGoogle Scholar
Evans, B.W. and Moore, J.G. (1968) Mineralogy as a function of depth in the pre-historic Makaopuhi tholeiitic lava lake, Hawaii. Contrib. Mineral. Petrol. 17, 85-115.CrossRefGoogle Scholar
Fabriès, J. (1979) Spinel-olivine geothermometry in peridotites from ultrabasic complexes. Contrib. Mineral. Petrol. 69, 329-36.CrossRefGoogle Scholar
Faithfull, J.W. (1985) The Lower Eastern Layered Series of Rhum. Geol. Mag. 122, 459-68.CrossRefGoogle Scholar
Finger, L.W. (1972) The uncertainty in the calculated ferric iron content of a microprobe analysis. Carnegie Institute Washington Yearbook 71, 600–603.Google Scholar
Fisk, M.R. and Bence, A.E. (1980) Experimental crystallization of chrome spinel in FAMOUS basalt 567-1-1. Earth Planet. Sci. Lett. 48, 111-23.CrossRefGoogle Scholar
Fitton, J.G. and Dunlop, H.M. (1985) The Cameroon line, West Afi'ica, and its bearing on the origin of oceanic and continental alkali basalt. Earth Planet. Sci. Lett. 72, 23–38.CrossRefGoogle Scholar
Gibb, F.G.F. (1969) Cognate xenoliths in the Tertiary ultrabasic dykes of south-west Skye. Mineral. Mag. 37, 504-14.CrossRefGoogle Scholar
Gibb, F.G.F. (1973). The zoned clinopyroxenes of the Shiant Isles sill, Scotland. J. Petrol., 14, 203-30.CrossRefGoogle Scholar
Gibb, F.G.F. (1976) Ultrabasic rocks of Rhum and Skye: The nature of the parent magma. J. Geol. Soc., London 132, 209-22.CrossRefGoogle Scholar
Green, D.H. and Ringwood, A.E. (1967) The genesis of basaltic magmas. Contrib. Mineral. and Petrol., 15, 103-90.CrossRefGoogle Scholar
Harris, C. (1983) The petrology of lavas and associated plutonic inclusions of Ascension Island. J. Petrol. 24, 424-70.CrossRefGoogle Scholar
Henderson, P. (1975) Reaction trends shown by chromespinels of the Rhum layered intrusion. Geochim. Cosmochim. Acta 39, 1035-44.CrossRefGoogle Scholar
Henderson, P. and Gijbels, R. (1976) Trace element indicators of the genesis of the Rhum layered intrusion, Inner Hebrides. Scottish J. Geol. 12, 325-33.CrossRefGoogle Scholar
Henderson, P. and Suddaby, P. (1971) The nature and origin of the chrome-spinel of the Rhum layered intrusion. Contrib. Mineral. Petrol. 33, 21-31.CrossRefGoogle Scholar
Henderson, P. and Wood, R.J. (1981) Reaction relationships of chrome-spinels in igneous rocks Further evidence from the layered intrusions of Rhum and Mull, Inner Hebrides, Scotland. Contrib. Mineral. Petrol. 78, 225-9.CrossRefGoogle Scholar
Hill, R. and Roeder, P. (1974) The crystallization of spinel from basaltic liquid as a function of oxygen fugacity... Geol. 82, 709-29.Google Scholar
Huppert, H.E. and Sparks, R.S.J. (1980) The fluid dynamics of a basaltic magma chamber replenished by an influx of hot dense ultrabasic liquid. Contrib. Mineral. Petrol. 75, 279-89.CrossRefGoogle Scholar
Irvine, T.N. (1987) Processes involved in the formation and development of layered igneous rocks. In: Parsons, I. (ed) Origins of Igneous Layering. Reidel, Dortrecht, 649-56.Google Scholar
Janošek, V., Rogers, G. and Bowes, D.R. (1995) Sr-Nd isotopic constraints on the petrogenesis of the Central Bohemian Pluton, Czech Republic. Geol. Rundsch. 84, 520-34.CrossRefGoogle Scholar
Kerr, A.C. (1995) The geochemistry of the Mull-Morvern Tertiary lava succession, NW Scotland: An assessment of mantle sources during plumerelated volcanism. Chem. Geol., 122, 43–58.CrossRefGoogle Scholar
Kerr, A.C., Kempton, P.D. and Thompson, R.N. (1995) Crustal assimilation during turbulent magma ascent (ATA); new isotopic evidence from the Mull Tertiary lava succession, N.W. Scotland. Contrib. Mineral. Petrol. 119, 142-54.CrossRefGoogle Scholar
Kitchen, D.E. (1985) The parental magma on Rhum: Evidence from alkaline segregations and veins in the peridotites from Salisbury's Dam. Geol. Mag., 122, 529-37.CrossRefGoogle Scholar
Kretz, R. (1982) Transfer and exchange equilibria in a portion of the pyroxene quadrilateral as deduced from natural and experimental data. Geochimic. Cosmochim. Acta 46, 411-21.CrossRefGoogle Scholar
Kudo, A.M. and Weill, D. (1970) An igneous plagioclase geothermometer. Contrib. Mineral. Petrol. 25, 52-65.CrossRefGoogle Scholar
Maaløe, S. (1976) The zoned plagioclase of the Skaergaard intrusion, East Greenland. J. Petrol., 17, 398–419.CrossRefGoogle Scholar
Mathez, E.A. (1973) Refinement of the Kudo-Weill plagioclase geothermometer and its application to basaltic rocks. Contrib. Mineral. Petrol. 41, 61–72.CrossRefGoogle Scholar
Mattey, D.P., Gibson, I.L., Marriner, G.F. and Thompson, R.N. (1977) The diagnostic geochemistry, relative abundance, and spatial distribution of high-calcium, low-alkali olivine tholeiite dykes in the Lower Tertiary regional swarm of the Isle of Skye, NW Scotland. Mineral. Mag., 41, 273-85.CrossRefGoogle Scholar
McBirney, A.R. and Hunter, R.H. (1995) The cumulate paradigm reconsidered. J. Geol. 103, 114-22.CrossRefGoogle Scholar
Munha, J., Palacios, T., MacRae, N.D. and Mata, J. (1990) Petrology of ultramafic xenoliths from Madeira island. Geol. Mag. 127, 543-66.CrossRefGoogle Scholar
Palacz, Z.A. and Tait, S.R. (1985) Isotopic and geochemical investigation of Unit 10 from the Eastern Layered Series of the Rhum Intrusion, Northwest Scotland. Geol. Mag. 122, 485-90.CrossRefGoogle Scholar
Preston, R.J. (1996) The petrogenesis of the Loch Scridain Xenolithic Sill Complex, Isle of Mull. Unpublished PhD thesis, University of Glasgow.Google Scholar
Reiners, P.W., Nelson, B.K. and Ghiorso, M.S. (1995) Assimilation of felsic crust by basaltic magma: Thermal limits and extents of crustal contamination of mantle-derived magmas. Geology 23, 563-6.2.3.CO;2>CrossRefGoogle Scholar
Reiners, P.W., Nelson, B.K. and Nelson, S.W. (1996) Evidence for multiple mechanisms of crustal contamination of magma from compositionally zoned plutons and associated ultramafic intrusions of the Alaska Range. J. Petrol. 37, 261-92.CrossRefGoogle Scholar
Ridley, W.I. (1977) The crystallization trends of spinels in Tertiary basalts from Rhum and Muck and their petrogenetic significance. Contrib. Mineral. Petrol. 64, 243-55.CrossRefGoogle Scholar
Roeder, P.L. and Emslie, R.F. (1970) Olivine-liquid equilibrium. Contrib. Mineral.Petrol., 29, 275–89.CrossRefGoogle Scholar
Roeder, P.L., Campbell, I.H. and Jamieson, H.E. (1979) A re-evaluation of the olivine-spinel geothermometer. Contrib. Mineral. Petrol. 68, 325-34.CrossRefGoogle Scholar
Scowen, P.A.H., Roeder, P.L. and Helz, R.T. (1991) Reequilibration of chromite within Kilauea Iki lava lake, Hawaii. Contrib. Mineral. Petrol., 107, 8-20.CrossRefGoogle Scholar
Sibley, D.F., Vogel, T.A., Walker, B.M. and Byerly, G. (1976) The origin of oscillatory zoning in plagioclase: A diffusion and growth controlled model. Amer. J. Sci., 276, 275-84.CrossRefGoogle Scholar
Sisson, T.W. and Grove, T.L. (1993) Experimental investigations of the role of H2O in calc-alkaline differentiation and subduction zone magmatism.. Contrib. Mineral. Petrol., 113, 143-66.CrossRefGoogle Scholar
Tait, S.R. (1985) Fluid dynamic and geochemical evolution of cyclic Unit 10, Rhum, Eastern Layered Series. Geol. Mag., 122, 469-84.CrossRefGoogle Scholar
Thirlwall, M.F. and Jones, N.W. (1983) Isotope geochemistry and contamination mechanics of Tertiary lavas from Skye, Northwest Scotland. In: Hawkesworth, C.J. and Norry, M.J. (eds.) Continental Basalts and Mantle Xenoliths. Shiva Publishing, Cheshire, 186–250.Google Scholar
Thompson, R.N. (1974) Primary basalts and magma genesis. I. Skye, North west Scotland. Contrib. Mineral. Petrol. 45, 317-41.CrossRefGoogle Scholar
Thompson, R.N., Esson, J. and Dunham, A.C. (1972) Major element chemical variation in the Eocene lavas of the Isle of Skye, Scotland. J. Petrol., 13, 219-53.CrossRefGoogle Scholar
Thompson, R.N., Gibson, I.L., Marriner, G.F., Mattey, D.P. and Morrison, M.A. (1980) Trace-element evidence of multistage mantle fusion and polybaric fractional crystallization in the Palaeocene lavas of Skye, NW Scotland. J. Petrol., 21, 265-93.CrossRefGoogle Scholar
Thompson, R.N., Morrison, M.A., Dickin, A.P., Gibson, I.L. and Harmon, R.S. (1986) Two contrasting styles of interaction between basic magmas and continental crust in the British Tertiary Volcanic Province. J. Geophys. Res., 91(B6), 5985-97.CrossRefGoogle Scholar
Tuttle, O.F. and Bowen, N.L. (1958). Origin of granite in the light of experimental studies in the system NaAISi3O8-KAISi3O8-SiO2-H2O. Geol. Soc. Amer. Memoirs, 74, 153pp.Google Scholar
Vance, J.A. (1962) Zoning in igneous plagioclase: Normal and oscillatory zoning. Amer. J. Sci. 260, 746-60.CrossRefGoogle Scholar
Van tier Laan, S.R. and Wyllie, P.J. (1993) Experimental interaction of granitic and basaltic magmas and implications for mafic enclaves. J. Petrol. 34, 491-517.CrossRefGoogle Scholar
Wager, L.R., and Brown, G.M. (1968) Layered Igneous Rocks. Oliver and Boyd, Edinburgh and London, 588 pp.Google Scholar
Wager, L.R., Brown, G.M. and Wadsworth, W.J. (1960) Types of igneous cumulate. J. Petrol. 1, 73-85.CrossRefGoogle Scholar
Walsh, J.N., Buckley, F. and Barker, J. (1981) The simultaneous determination of the rare earth elements in rocks using inductively coupled plasma source spectrometry. Chem. Geol. 33, 141-53.CrossRefGoogle Scholar
Young, I.M. (1984) Mixing of supernatant and intercumulus fluids in the Rhum layered intrusion. Mineral. Mag. 48, 345-50.CrossRefGoogle Scholar