Reaction Space: Transition from Eclogite to Amphibolite Facies in An Ultra-high Pressure Metamorphic Terrane from Zhucheng, Shandong, E. China

Mineralogy ◽  
2020 ◽  
pp. 135-149
Author(s):  
Lai Xingyun ◽  
Su Shangguo
Keyword(s):  
High Pressure ◽  
Amphibolite Facies ◽  
Reaction Space ◽  
Ultra High Pressure ◽  
Metamorphic Terrane

Ultra-high pressure aluminous titanites in carbonate-bearing eclogites at Shuanghe in Dabieshan, central China

1996 ◽  
Vol 60 (400) ◽  
pp. 461-471 ◽  
Author(s):  
D. A. Carswell ◽  
R. N. Wilson ◽  
M. Zhai
Keyword(s):  
High Pressure ◽  
Phase Equilibria ◽  
Amphibolite Facies ◽  
Central China ◽  
Stability Field ◽  
Ultra High Pressure ◽  
Metamorphic Fluids ◽  
Metamorphic Terrane ◽  
The Stability ◽  
Peak Assemblage

AbstractPetrographic features and compositions of titanites in eclogites within the ultra-high pressure metamorphic terrane in central Dabieshan are documented and phase equilibria and thermobarometric implications discussed. Carbonate-bearing eclogite pods in marble at Shuanghe contain primary metamorphic aluminous titanites, with up to 39 mol.% Ca(Al,Fe3+)FSiO4 component. These titanites formed as part of a coesite-bearing eclogite assemblage and thus provide the first direct petrographic evidence that AlFTi−1O−1 substitution extends the stability of titanite, relative to rutile plus carbonate, to pressures within the coesite stability field. However, it is emphasised that A1 and F contents of such titanites do not provide a simple thermobarometric index of P—T conditions but are constrained by the activity of fluorine, relative to CO2, in metamorphic fluids — as signalled by observations of zoning features in these titanites.These ultra-high pressure titanites show unusual breakdown features developed under more H2O-rich amphibolite-facies conditions during exhumation of these rocks. In some samples aluminous titanites have been replaced by ilmenite plus amphibole symplectites, in others by symplectitic intergrowths of secondary, lower Al and F, titanite plus plagioclase. Most other coesite-bearing eclogite samples in the central Dabieshan terrane contain peak assemblage rutile often partly replaced by grain clusters of secondary titanites with customary low Al and F contents.

U–Pb zircon geochronology of eclogites from the Scandian Orogen, northern Western Gneiss Region, Norway: 14–20 million years between eclogite crystallization and return to amphibolite-facies conditionsThis article is one of a series of papers published in this Special Issue on the theme of Geochronology in honour of Tom Krogh.

2011 ◽  
Vol 48 (2) ◽  
pp. 441-472 ◽  
Author(s):  
Thomas E. Krogh ◽  
Sandra L. Kamo ◽  
Peter Robinson ◽  
Michael P. Terry ◽  
Kim Kwok
Keyword(s):  
High Pressure ◽  
Continental Collision ◽  
Amphibolite Facies ◽  
Granitic Pegmatite ◽  
Zircon Geochronology ◽  
Plate Tectonic ◽  
Special Issue ◽  
Western Gneiss Region ◽  
Garnet Pyroxenite ◽  
Ultra High Pressure

Reconstructing tectonic histories involving continental collision, subduction, and exhumation at plate-tectonic rates of ∼1 cm/year, requires precise U–Pb zircon geochronology. The Western Gneiss Region has exceptional exposures of high-pressure (HP) and ultra-high-pressure (UHP) rocks. The strategy adopted here involved sampling eclogite and associated late unstrained pegmatites to acquire the time of eclogite crystallization and subsequent exhumation, respectively. The oldest eclogite sampled is 415 ± 1 Ma from layered, probably UHP eclogite at Tevik, Averøya, also with a garnet–hornblende assemblage at 410 ± 1 Ma. The Flem Gabbro eclogite margin, with implied UHP conditions, is 410 ± 2 Ma. Hornblende eclogite at Seth, Lepsøya, never at UHP, is 412 ± 2 Ma. These compare to Devonian ages of 401 ± 1 Ma for overgrowths on Proterozoic baddeleyite in Selnes Gabbro, 402 ± 2 Ma for coesite eclogite at Hareidlandet, 405–400 Ma for coesite eclogite at Flatraket, and 405 ± 2 Ma for near-UHP eclogite at Hjelmelandsdalen. The 415 Ma eclogite at Tevik compares to granitic pegmatite in the same outcrop at 395.2 ± 1.3 Ma and to pegmatite in eclogite at Aspøya at 395.3 ± 2 Ma. The 410 Ma age at Flem compares to nearby pegmatite in eclogite at 396 ± 4 Ma. Collectively, these results imply 14–20 million years between deep eclogite crystallization at ∼130 km and return to amphibolite-facies conditions at ∼30 km, with crystallization of locally derived granitoid melts. Nearby garnet-pyroxenite records older ages (∼430) and greater depths (∼200 km), but on similar exhumation paths at ∼0.4–0.7 cm/year.

Decoupling of the Lu–Hf, Sm–Nd, and Rb–Sr isotope systems in eclogites and a garnetite from the Sulu ultra-high pressure metamorphic terrane: Causes and implications

Lithos ◽  
2015 ◽  
Vol 234-235 ◽  
pp. 1-14 ◽  
Author(s):  
Yung-Hsin Liu ◽  
Huai-Jen Yang ◽  
Eiichi Takazawa ◽  
Madhusoodhan Satish-Kumar ◽  
Chen-Feng You
Keyword(s):  
High Pressure ◽  
Sr Isotope ◽  
Ultra High Pressure ◽  
Metamorphic Terrane

Experimental constraints on the genesis of Jadeite quartzite from Shuanghe, Dabie Mountain ultra-high pressure metamorphic terrane

2013 ◽  
Vol 57 (1) ◽  
pp. 104-116 ◽  
Author(s):  
YanFei Zhang ◽  
Yao Wu ◽  
Chao Wang ◽  
ZhenMin Jin ◽  
Hans-Peter Schertl
Keyword(s):  
High Pressure ◽  
Dabie Mountain ◽  
Ultra High Pressure ◽  
Metamorphic Terrane

scholarly journals Phengite megacryst quasi-exsolving phlogopite, from Sulu ultra-high pressure metamorphic terrane, Qinglongshan, Donghai County (eastern China): New data for P-T-X conditions during exhumation

Lithos ◽  
2018 ◽  
Vol 314-315 ◽  
pp. 156-164 ◽  
Author(s):  
Nadia Curetti ◽  
Costanza Bonadiman ◽  
Roberto Compagnoni ◽  
Luca Nodari ◽  
Ingrid Corazzari ◽  
...  
Keyword(s):  
High Pressure ◽  
Eastern China ◽  
Ultra High Pressure ◽  
Metamorphic Terrane

scholarly journals Trans-lithospheric diapirism explains the presence of ultra-high pressure rocks in the European Variscides

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Petra Maierová ◽  
Karel Schulmann ◽  
Pavla Štípská ◽  
Taras Gerya ◽  
Ondrej Lexa
Keyword(s):  
High Pressure ◽  
Numerical Models ◽  
Classical Concept ◽  
Plate Interface ◽  
Ultra High Pressure ◽  
Common Process ◽  
Mountain Belts ◽  
Collisional Orogens ◽  
Rock Association ◽  
European Variscides

AbstractThe classical concept of collisional orogens suggests that mountain belts form as a crustal wedge between the downgoing and overriding plates. However, this orogenic style is not compatible with the presence of (ultra-)high pressure crustal and mantle rocks far from the plate interface in the Bohemian Massif of Central Europe. Here we use a comparison between geological observations and thermo-mechanical numerical models to explain their formation. We suggest that continental crust was first deeply subducted, then flowed laterally underneath the lithosphere and eventually rose in the form of large partially molten trans-lithospheric diapirs. We further show that trans-lithospheric diapirism produces a specific rock association of (ultra-)high pressure crustal and mantle rocks and ultra-potassic magmas that alternates with the less metamorphosed rocks of the upper plate. Similar rock associations have been described in other convergent zones, both modern and ancient. We speculate that trans-lithospheric diapirism could be a common process.

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