| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Journal of Petrology Volume 42 Number 11 Pages 1995-2013 2001
© Oxford University Press 2001
PTt Evolution of Ultrahigh-Temperature Granulites from the Saxon Granulite Massif, Germany. Part I: Petrology
1INSTITUT FÜR GEOWISSENSCHAFTEN, UNIVERSITÄT POTSDAM, POSTFACH 60 15 53, 14415 POTSDAM, GERMANY
2GEOFORSCHUNGSZENTRUM POTSDAM, TELEGRAFENBERG, 14473 POTSDAM, GERMANY
The granulites of the Saxon Granulite Massif equilibrated at high pressure and ultrahigh temperature and were exhumed in large part under near-isothermal decompression. This raises the question of whether PTt data on the peak metamorphism may still be retrieved with confidence. Felsic and mafic granulites with geochronologically useful major and accessory phases have provided a basis to relate PT estimates with isotopic ages presented in a companion paper. The assemblage garnet + clinopyroxene in mafic granulite records peak temperatures of 10101060°C, consistent with minimum estimates of around 967°C and 22·3 kbar obtained from the assemblage garnet + kyanite + ternary feldspar + quartz in felsic granulite. Multiple partial overprint of these assemblages reflects a clockwise PT evolution. Garnet and kyanite in the felsic granulite were successively overgrown by plagioclase, spinel + plagioclase, sapphirine + plagioclase, and biotite + plagioclase. Most of this overprinting occurred within the stability field of sillimanite. Garnet + clinopyroxene in the mafic granulite were replaced by clinopyroxene + amphibole + plagioclase + magnetite. The high PT conditions and the absence of thermal relaxation features in these granulites require a short-lived metamorphism with rapid exhumation. The ages of peak metamorphism (342 Ma) and shallow-level granitoid intrusions (333 Ma) constrain the time span for the exhumation of the Saxon granulites to
9 my.
KEY WORDS: ultrahigh-temperature metamorphism; granulite; thermobarometry; exhumation; Saxon Granulite Massif
![]()
CiteULike
Connotea
Del.icio.us What's this?
This article has been cited by other articles:
![]() |
T. Ohba, K. Matsuoka, Y. Kimura, H. Ishikawa, and H. Fujimaki Deep Crystallization Differentiation of Arc Tholeiite Basalt Magmas from Northern Honshu Arc, Japan J. Petrology, June 1, 2009; 50(6): 1025 - 1046. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Rotzler, B. Hagen, and S. Hoernes Geothermometry of the ultrahigh-temperature Saxon granulites revisited. Part I: New evidence from key mineral assemblages and reaction textures European Journal of Mineralogy, December 1, 2008; 20(6): 1097 - 1115. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Hagen, S. Hoernes, and J. Rotzler Geothermometry of the ultrahigh-temperature Saxon granulites revisited. Part II: Thermal peak conditions and cooling rates inferred from oxygen-isotope fractionations European Journal of Mineralogy, December 1, 2008; 20(6): 1117 - 1133. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Nakano, Y. Osanai, and M. Owada Multiple breakdown and chemical equilibrium of silicic clinopyroxene under extreme metamorphic conditions in the Kontum Massif, central Vietnam American Mineralogist, November 1, 2007; 92(11-12): 1844 - 1855. [Abstract] [Full Text] [PDF] |
||||
![]() |
U. Kroner, T. Hahn, R. L. Romer, and U. Linnemann The Variscan orogeny in the Saxo-Thuringian zone--Heterogenous overprint of Cadomian/Paleozoic Peri-Gondwana crust Geological Society of America Special Papers, January 1, 2007; 423(0): 153 - 172. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. JANOUSEK, A. GERDES, S. VRANA, F. FINGER, V. ERBAN, G. FRIEDL, and C. J. R. BRAITHWAITE Low-pressure Granulites of the Lisov Massif, Southern Bohemia: Visean Metamorphism of Late Devonian Plutonic Arc Rocks J. Petrology, April 1, 2006; 47(4): 705 - 744. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. ROTZLER, R. L. ROMER, H. BUDZINSKI, and R. OBERHANSLI Ultrahigh-temperature high-pressure granulites from Tirschheim, Saxon Granulite Massif, Germany: P-T-t path and geotectonic implications European Journal of Mineralogy, December 1, 2004; 16(6): 917 - 937. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. J. Timmerman Timing, geodynamic setting and character of Permo-Carboniferous magmatism in the foreland of the Variscan Orogen, NW Europe Geological Society, London, Special Publications, January 1, 2004; 223(1): 41 - 74. [Abstract] [PDF] |
||||
![]() |
M. Okrusch, R. Hock, U. Schussler, A. Brummer, M. Baier, and H. Theisinger Intergrown niobian rutile phases with Sc- and W-rich ferrocolumbite: An electron-microprobe and Rietveld study American Mineralogist, July 1, 2003; 88(7): 986 - 995. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. R. MARSCHALL, A. KALT, and M. HANEL P-T Evolution of a Variscan Lower-Crustal Segment: a Study of Granulites from the Schwarzwald, Germany J. Petrology, February 1, 2003; 44(2): 227 - 253. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. L. Romer and J. Rotzler Effect of metamorphic reaction history on the U-Pb dating of titanite Geological Society, London, Special Publications, January 1, 2003; 220(1): 147 - 158. [Abstract] [PDF] |
||||
![]() |
R. MORAES, M. BROWN, R. A. FUCK, M. A. CAMARGO, and T. M. LIMA Characterization and P-T Evolution of Melt-bearing Ultrahigh-temperature Granulites: an Example from the Anapolis-Itaucu Complex of the Brasilia Fold Belt, Brazil J. Petrology, September 1, 2002; 43(9): 1673 - 1705. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. L. ROMER and J. ROTZLER P-T-t Evolution of Ultrahigh-Temperature Granulites from the Saxon Granulite Massif, Germany. Part II: Geochronology J. Petrology, November 1, 2001; 42(11): 2015 - 2032. [Abstract] [Full Text] [PDF] |
||||




