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Differential exhumation was petrologically recognized in ultrahigh pressure metamorphic rocks from the southern and northern parts of the Sulu terrane. While a normal exhumation occurred for eclogites and gneisses in south Sulu, granulite-facies overprinting of ultrahigh pres- sure metamorphic rocks took place with high retrograde temperatures in north Sulu. A study of fluid inclusions re- veals trapping of five type fluid inclusions in high and ultra- high pressure eclogite minerals and vein quartz in the Sulu terrane. These are A-type N2±CO2 inclusion trapped at high and ultra-high pressure eclogite-facies metamorphic condi- tion, B-type pure-CO2 liquid phase inclusion with higher density trapped during granulite-facies overprinting meta- morphism of eclogites, C-type CO2-H2O inclusion and D-type hypersaline inclusion trapped in high pressure eclogite-facies re-crystallization stage, and E-type low salinity H2O inclu- sion trapped in the latest stage of ultrahigh pressure exhu- mation (amphibolite-facies retrogression). Identification of crowded-distributing pure-CO2 liquid inclusions with higher density trapped in garnet of eclogites provides an evidence for granulite-facies overprinting metamorphism in the north Sulu terrane.
Differential exhumation was petrologically recognized in ultrahigh pressure metamorphic rocks from the southern and northern parts of the Sulu terrane. While a normal exhumation occurred for eclogites and gneisses in south Sulu, granulite-facies overprinting of ultrahigh pres- sure metamorphic rocks took place with high retrograde temperatures in north Sulu. A study of fluid inclusions re- veals trapping of five type fluid inclusions in high and ultra-high pressure eclogite minerals and vein quartz in the Sulu terrane. These are A-type N2 ± CO2 inclusion trapped at high and ultra -high pressure eclogite-facies metamorphic condi- tion, B-type pure-CO2 liquid phase inclusion with higher density trapped during granulite-facies overprinting meta-morphism of eclogites, C-type CO2-H2O inclusion and D-type hypersaline inclusion trapped in high pressure eclogite-facies re-crystallization stage, and E-type low salinity H2O inclusions trapped in the latest stage of ultrahigh pressure exhumati on (amphibolite-facies retrogression). Identification of crowded-distributing pure-CO2 liquid inclusions with higher density trapped in garnet of eclogites provide an evidence for granulite-facies overprinting metamorphism in the north Sulu terrane.