Refining the P–T records of UHT crustal metamorphism
Tóm tắt
Ultra‐high‐temperature (UHT) metamorphism occurs when the continental crust is subjected to temperatures of greater than 900 °C at depths of 20–40 km. UHT metamorphism provides evidence that major tectonic processes may operate under thermal conditions more extreme than those generally produced in numerical models of orogenesis. Evidence for UHT metamorphism is recorded in mineral assemblages formed in magnesian pelites, supported by high‐temperature indicators including mesoperthitic feldspar, aluminous orthopyroxene and high Zr contents in rutile. Recent theoretical, experimental and thermodynamic data set constraints on metamorphic phase equilibria in FMAS, KFMASH and more complex chemical systems have greatly improved quantification of the
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Aranovich L. Ya., 1989, Evolution of Metamorphic Belts, 45
Degeling H. S. 2003.Zr Equilibria in Metamorphic Rocks.Unpublished PhD Thesis Australian National University Canberra Australia 231 pp.
Grew E. S., 1980, Sapphirine + quartz association from Archaean rocks in Enderby Land, Antarctica, American Mineralogist, 65, 821
Grew E. S., 1982, Osumilite in the sapphirine‐quartz terrane of Enderby Land, Antarctica: implications for osumilite petrogenesis in the granulite facies, American Mineralogist, 67, 762
Harley S. L., 1998, What Controls Metamorphism and Metamorphic Reactions, 75
Harley S. L., 1998, Origin and Evolution of Continents, 49
Hensen B. J., 1988, Chemical potential diagrams and chemographic projections: application to sapphirine‐granulites from Kiranur and Ganguvarpatti, Tamil Nadu. Evidence for rapid uplift in part of the South Indian Shield, Neues Jahrbuch für Mineralogie Abhandlungen, 158, 193
Herd R. K., 1986, The Grenville Province, 241
Mohan A., 1986, Reaction textures and P–T–X trajectory in the sapphirine‐spinel bearing granulites from Ganguvarpatti, Southern India, Neues Jahrbuch Mineralogie Abhandlungen, 154, 1
Motoyoshi Y., 1997, The Antarctic Region: Geological Evolution and Processes, 65
Motoyoshi Y., 1994, Reaction textures in granulites from Forefinger Point, Enderby Land, East Antarctica: an alternative interpretation on the metamorphic evolution of the Rayner Complex, Proceedings National Institute of Polar Research Symposium on Antarctic Geosciences, 7, 101
Newton R. C., 1972, An experimental determination of the high‐pressure stability limits of magnesian cordierite under wet and dry conditions, Journal of Geophysical Research, 80, 398
Podlesskii K. K., 2006, Geothermobarometry of Orthopyroxene‐bearing Aluminous Granulites based on Internally Consistent Thermodynamic Datasets
Sandiford M., 1986, Pyroxene exsolution in granulites from Fyfe Hills, Enderby Land, Antarctica: evidence for 1000°C metamorphic temperatures in Archaean continental crust, American Mineralogist, 71, 946