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Blueschist and eclogite in tectonic melange, Port Macquarie, New South Wales, Australia

Published online by Cambridge University Press:  05 July 2018

D. J. Och*
Affiliation:
Environmental Sciences, University of Technology, Sydney, NSW 2007, Australia
E. C. Leitch
Affiliation:
Environmental Sciences, University of Technology, Sydney, NSW 2007, Australia
G. Caprarelli
Affiliation:
Environmental Sciences, University of Technology, Sydney, NSW 2007, Australia
T. Watanabe
Affiliation:
Earth and Planetary Sciences, Graduate School of Science, Hokkaido University, Sapporo, Japan, 060

Abstract

The Rocky Beach Metamorphic Melange contains metre-scale phacoids of high-P low-T metamorphic rocks embedded in chlorite-actinolite schist. The phacoids include eclogite, glaucophane schist and omphacitite and provide evidence for four episodes of metamorphism with mineral assemblages: M1 = actinolite-glaucophane-titanite-apaite, M2 = almandine-omphacite-lawsonite ±quartz, M3 = phengite- glaucophane-K-feldspar-quartz, and M4 = chlorite-actinolite-calcite-quartz-titanite-white mica ± albite ± talc. M1-M3 occurred at a Neoproterozoic-Early Palaeozoic convergent plate boundary close to the eastern margin of Gondwana. Peak metamorphic conditions were attained during the static phase M2, with temperatures of ~560°C and pressures in excess of 1.8 GPa, equivalent to a depth of burial of at least 54 km.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2003

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Footnotes

Present address: Douglas Partners Pty Ltd, 96 Hermitage Rd, West Ryde, NSW 2114, Australia

Deceased

References

Aitchison, J.C., Clark Blake, M. Jr., Flood, P.G. and Jayko, A.S. (1994 Palaeozoic ophiolitic assemblages within the southern New England Orogen of eastern Australia: Implications for growth of the Gondwana margin. Tectonics, 13, 11351149.CrossRefGoogle Scholar
Barron, B.J., Scheibner, E. and Slansky, E. (1976 A dismembered ophiolite suite at Port Macquarie, New South Wales. Records of the Geological Survey of New South Wales, 18, 69102.Google Scholar
Brown, E.H. (1977 The crossite content of Caamphibole as a guide to pressure of metamorphism. Journal of Petrology, 18, 5372.CrossRefGoogle Scholar
Bucher, K. and Frey, M. (1994 Petrogenesis of Metamorphic Rocks . Springer-Verlag, Berlin, New York.CrossRefGoogle Scholar
Bundy, F.R. (1980 Th. P, T phase reaction diagrams for elemental carbon. Journal of Geophysical Research, 85, 69306936.Google Scholar
Caprarelli, G. and Leitch, E.C. (2001 Geochemical evidence from Lower Permian volcanic rocks of northeast New South Wales for asthenospheric upwelling following slab breakoff. Australian Journal of Earth Sciences, 48, 151166.CrossRefGoogle Scholar
Carson, C.J., Clarke, G.L. and Powell, R. (2000 Hydration of eclogite, Pam Peninsul a, New Caledonia. Journal of Metamorphic Geology, 18, 7990.CrossRefGoogle Scholar
Coleman, R.G., Lee, D.E., Beatty, L.B. and Brannock, W.W. (1965 Eclogites and eclogites: their differences and similarities. Geological Society of America Bulletin, 76, 483508.CrossRefGoogle Scholar
Droop, G.G.T. (1987 A general equation for estimating Fe3+ concentrations in ferromagnesian silicates and oxides from microprobe analysis, using stoichiometric criteria. Mineralo gical Magazine, 51, 431435.CrossRefGoogle Scholar
Eide, E.A. and Lardeaux, J.-M. (2002 A relict blueschist in meta-ophiol ite from the central Norwegian Caledonides discovery and consequences. Lithos, 60, 119.CrossRefGoogle Scholar
El-Shazly, A.K. (2001 Are pressures for blueschists and eclogites overestimated? The case from NE Oman. Lithos, 56, 231264.CrossRefGoogle Scholar
Essene, E.J. and Fyfe, W.S. (1967 Omphacite in Californian metamorphic rocks. Contributions to Mineralogy and Petrology, 15, 123.CrossRefGoogle Scholar
Fergusson, C.L., Henderson, R.A., Leitch, E.C. and Ishiga, H. (1993 Lithology and structure of the Wandilla terrane, Gladstone-Yeppoon district, central Queensland, and an overview of the Palaeozoic subduction complex of the New England Fold Belt. Australian Journal of Earth Sciences, 40, 403414.CrossRefGoogle Scholar
Forster, M.A. and Lister, G.S. (1999 Separate episodes of eclogite and blueschist facies metamorphism in the Aegean metamorphic core complex of Ios, Cyclades, Greece. Pp. 157177 in: Continental Tectonics (Mac Niocaill, C. and Ryan, P.D., editors). Special Publication, 164, Geological Society, London.Google Scholar
Fryer, P., Mottl, M.J., Johnson, L., Haggerty, J., Phipps, S. and Maekawa, H. (1995 Serpentinite bodies in the forearc of western Pacific convergent margins: origin and associated fluids. Pp. 259279 in: Active Margins and Marginal Basins of the Western Pacific (Taylor, B. and Natland, J., editors). American Geophysical Union, Washington DC.CrossRefGoogle Scholar
Fukui, S., Watanabe, T., Itaya, T. and Leitch, E.C. (1995 Middle Ordovician high PT metamorphic rocks in eastern Australia: Evidence from K-Ar ages. Tectonics, 14, 10141020.CrossRefGoogle Scholar
Hatton, O.J. (1997 High-Pressure Metamorphic Rocks of the Pigna Barney Ophiolite Complex and Port Macquarie Complex NSW . Unpubl. Honours thesis, University of Technology, Sydney, Australia.Google Scholar
Hey, M.H. (1954 A new review of the chlorites. Mineralogical Magazine , 30, 277.CrossRefGoogle Scholar
Holland, T.T.J. (1980 The reaction albite = jadeite + quartz determined experimentally in the range 600—1200°C. American Mineralogist, 65, 129134.Google Scholar
Holland, T.T.J. (1983 The experimental determination of activities in disordered and short-range ordered jadeitic pyroxenes. Contributions to Mineralogy and Petrology, 82, 214220.CrossRefGoogle Scholar
Holland, T.T.J. and Powell, R. (1998 An internally consistent thermodynamic data set for phases of petrological interest. Journal of Metamorphic Geology, 16, 309343.CrossRefGoogle Scholar
Krogh, E.R. (2000 The garnet – clinopyroxene Fe2+–Mg geothermometer: an updated calibration. Journal of Metamorphic Geology, 18, 211219.CrossRefGoogle Scholar
Leake, B.E., Woolley, A.R., Arps, C., Birch, W.D., Gilbert, M.C., Grice, J.D., Hawthorne, F.C., Kato, A., Kisch, H.J., Krivovichev, V.G., Linthout, K., Laird, J., Mandarino, J.A., Maresch, W.V., Nickel, E.H., Rock, N.N.M., Schumacher, J.C., Smith, D.C., Stephenson, N.N.C., Ungaretti, L.,Whittaker, E.E.J. and Youzhi, G. (1997 Nomenclature of amphiboles: report of the subcommittee on amphiboles of the Int e rn at io na l Mine r alog i ca l As so ci a t io n, Commission on New Minerals and Mineral Names. The Canadian Mineralogist, 35, 219246.Google Scholar
Leitch, E.C. (1980 Rock units, structure and metamorphism of the Port Macquarie Block, eastern New England Fold Belt. Proceedings of the Linnean Society of New South Wales, 104, 273292.Google Scholar
Maresch, W.V. (1977 Experimental studies on glaucophane: An analy si s of presen t knowl edge. Tectonophysics, 43, 109125.CrossRefGoogle Scholar
Massonne, H.J. and Schreyer, W. (1987 Phengite geobarometry based on the limiting assemblage with K-feldspar, phlogopite, and quartz. Contributions to Mineralogy and Petrology, 96, 212224.CrossRefGoogle Scholar
Morimoto, N., Fabries, J., Ferguson, A.K., Ginzburg, I.V., Ross, M., Seifert, F.A., Zussman, J., Aoki, K. and Gottardi, G. (1988 Nomenclature of Pyroxenes. Schweizerische Mineralogische und Petrographische Mitteilungen, 68, 95111.Google Scholar
Offler, R. (1999 Origin and significance of blueschist “knockers”, Glenrock Station, NSW. Pp. 3544 in: NEO 99 (Flood, P.G., editor). Earth Sciences, The University of New England.Google Scholar
Piepenbreier, D. and Stöckhert, B. (2001 Plastic flow of omphacite in eclogites at temperatures below 500ºC – implications for interplate coupling in subduction zones. International Journal of Earth Sciences, 89, 197210.CrossRefGoogle Scholar
Platt, J.P. (1986 Dynamics of orogenic wedges and the uplift of high-pressure metamorphic rocks. Geological Society of America Bulletin, 97, 10371053.2.0.CO;2>CrossRefGoogle Scholar
Quodling, F.M. (1964 On Traces of Native Iron at Port Macquarie, New South Wales. Journal and Proceedings, Royal Society of New South Wales, 97, 8182.Google Scholar
Sherlock, S.C. and Okay, A.I. (1999 Oscillatory zoned chrome lawsonite in the Tavsanli Zone, northwest Turkey. Mineralogical Magazine, 63, 687692.CrossRefGoogle Scholar
Smith, C.A., Sisson, V.B., Ave Lallemant, H.G. and Copeland, P. (1999 Two contrasting temperaturetime paths in the Villa de Cura blueschist belt, Venezuela: Possible evidence for Late Cretaceous initiation of subduction in the Caribbean. Geological Society of America Bulletin, 111, 831848.2.3.CO;2>CrossRefGoogle Scholar
Tsujimori, T. (1997 Omphacite-diopside vein in an omphacitite block from the Osayama serpentinite melange, Sangun-Renge metamorphic belt, southwestern Japan. Mineralogi cal Magazine, 61, 845852.CrossRefGoogle Scholar
Watanabe, T., Leitch, E.C. and Fanning, M. (1997 The age and tectonic significance of lawsonite eclogite and high temperature eclogite blocks in serpentinite melange from the southern New England Fold Belt, Eastern Australia. P. 110 in: IEC 97, Terra Nova.Google Scholar
Watanabe, T., Fanning, C.M., Leitch, E.C., Morita, T., Wada, T. and Agashev, A. (1999a) Neoproterozoic Attunga eclogite and pre-Ordovician lawsonite eclogite in serpentinite melange of the New England Fold Belt, eastern Australia. Pp. 2728 in: Fourth International Eclogite Field Symposium, Workshop: Eclogites, high- and ultrahigh-pressure Metamorphic Rocks . Russian Academy of Sciences and Ministry of Ecology and Natural Resources (Kazakhstan), Novosibirsk, Russia.Google Scholar
Watanabe, T., Orihashi, T. and Fanning, C.M. (1999b) Latest Neo-Proterozoic Gondwana eastern margin. Gondwana Research (Gondwana Newslette r Section) , 2, 291292.CrossRefGoogle Scholar