NEW METHOD FOR CARBON-DIOXIDE DENSITY AND SALINITY DETERMINATION FROMCLATHRATE MELTING TEMPERATURE IN FLUID INCLUSIONS OF THE H2O-CO2-NACLCOMPOSITION

New methods for calculation of the salinity (C, wt%), carbon dioxide d ensity (dCO2) and the phase volume ratio (FG) are proposed for fluid i nclusions of the H2O-CO2-NaCl composition, when CO2 homogenization tem perature (T(h)) in less than clathrate melting point (T(cl)). Results of the fluid inclusions microthermometric study are used as initial da ta. The proposed method allow to determine carbon dioxide density in t he case,when CO2 homogenization can not be observed in fluid inclusion s with low CO2 density (dCO2 < 0.13 g/cm3). Hence, compositions of the fluids containing small amounts of carbon dioxide (XCO2 < 3 mol%), ar e suitable for quantitative calculation. The visual estimate of the fl uid inclusion FG is required for calculation of the solution concentra tion, when T(h) can not be obtained during the microthermometric study . In the other case, C and FG may br calculated by using proposed meth od with numerical solution equations of the mass balance. An abandonme nt of the visual FG estimation is essentially improve the accuracy of the fluid composition calculation.Microcomputer program ''CLATCOM'' is created for application of the proposed method. ''CLATCOM'' program, which brief description is given, allows to calculate fluid compositio ns, its densities, molar volumes and isochores.