Fluid Inclusion Stratigraphy (FIS) is a method currently being developed for use in geothermal systems to identify fractures and fluid types. This paper is the second in a series of papers on the development of FIS. Fluid inclusion gas geochemistry is analyzed and plotted on well log diagrams. The working hypothesis is that select gaseous species and species ratios indicate areas of groundwater and reservoir fluid flow and reservoir seals. Analyses have shown that it is possible to not only identify fluid types but also fractures. Analyses are performed by a commercial laboratory, Fluid Inclusion Technologies.

The FIS method shows much fine scale detail when the logs are analyzed. Two sampling intervals have been evaluated to determine the optimal sampling interval for the method. The fine scale detail has been compared against fracture logs for one drill hole to evaluate the FIS technique for locating fractures. Additionally, FIS samples were obtained from a core sample to evaluate how far away from the fracture center, fluid inclusions occur. Fluid types have been determined based on select chemical species such as H2S as well as ratios including (N2/Ar + CO2/CH4) / (Mass 43/Mass 39) and H2S / N2.

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