Phase behavior and fluid interactions of a CO2-Light oil system at high pressures and temperatures

New phase diagram of oxygen at high pressures and temperatures.

In situ high P-T Raman measurements and optical observations of solid and fluid oxygen up to 1250 K between 8 and 25 GPa reveal the existence of a new molecular phase eta and strikingly unusual behavior of the melting curve. Three triple points were also identified in the P-T domain of the new phase. The data give a direct measure of the melting curve that greatly extends previous optical inves...

Fluids at high pressures and temperatures

With high pressures, supercritical fluids can be studied over a very wide range of density. Fluids with strongly interacting polar molecules for example water are of particular interest. Results for several thermophysical properties are discussed. Density, dielectric constant and self—ionization of water have been determined or predicted to 1000 °C. Beyond 20 GPa very hot water appears to becom...

Synthetic fluid inclusions: XVI. PVTX properties in the system H2O-NaCl-CO2 at elevated temperatures, pressures, and salinities

The ternary system H2O-NaCl-CO2 is one of the most important fluid systems in geochemistry and petrology. However, there is little information on the phase equilibrium and PVT properties in this system at salinities above 6 wt.% NaCl. In this study, PVTX data were obtained experimentally by using the synthetic fluid inclusion technique in conjunction with conventional microthermometry and a hyd...

Electrical conductivity of wadsleyite at high temperatures and high pressures

New phases of N2O4 at high pressures and high temperatures

High P–T studies of molecular N2O4 using Raman, synchrotron infrared, and X-ray diffraction measurements reveal several new phenomena. Significant changes in the vibrational spectra indicate a phase transition at about 12 GPa. The X-ray diffraction measurements show that the material remains cubic through the transition. We ascribe the transition to a change in the molecular geometry of N2O4 wi...