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Fluid inclusions have been studied in garnetiferous gneisses and igneous charnockites from Weddagala, Sri Lanka. Fluid distribution (brines in metasediments, in charnockites) compares well with other regions, notably Bamble (southern Norway). For the brines, it suggests an ultimate pre-metamorphic origin and for , initial entrapment during metamorphic crystallization. The fluid density has been completely reset during post-metamorphic evolution. Maximum densities indicate much lower pressure than those at peak metamorphic conditions recorded by the solid assemblages (about 5 vs. 8 kbars). The evolution of densities with time suggests a post-metamorphic trajectory concave toward the pressure axis ("Adiabatic uplift") and local redistribution and reequilibration of inclusions between 500 and 600°C. Fluid movements were mostly limited to grain scale (millimeter order of magnitude) and did not transgress the lithological boundaries.