Understanding reservoir fluids: A cost effective alternative





Geolog offers a comprehensive array of technologies at the rig site, able to analyse a wide molecular spectrum from C1 through to C35, looking at both mud gas and cuttings to enable fuller understanding of the hydrocarbons in place in near real time without requiring formation fluid sampling.

Geolog’s G8 service analyses heavy gasses in the range C6 to C8 directly from the mud system, allowing previously unseen components between conventional mud gas chromatography and formation fluid samples to be incorporated into assessments of the reservoir.

The patented G9+ system extends this compositional analysis to C35, using a unique thermal desorption process to allow the analysis of long chain hydrocarbons, enabling reservoir fluid fingerprinting to be performed at the rigsite utilising available cuttings.

In addition, Geolog has pioneered rigsite technology to go beyond standard molecular compositional analysis, with the patented GeoIsotopes uniquely capable of providing continuous measurements of stable carbon isotope ratios in C1, C2 and C3. This advance has opened a new realm of data, promoting a deeper understanding of oil and gas fields, reservoir compartmentalisation, source rock correlation, reservoir maturity and the differences between reservoir oils and their source rocks.

Thanks to combination of these technologies, Geolog has developed wide experience of data integration and prediction of oil and gas properties, including Oil density, GOR, CGR.

As these technologies deliver continues measurements, the oil and gas properties identified can be integrated with reservoir modelling for multiple purposes: geometry of GOC and OWC, oil property mapping, vertical oil density gradients, etc. The data also allows the interpretation of which factors are most impacting the oil and its quality variations: biodegradation, maturity, water washing, evaporative fraction etc.  helping to make the best decision for field development in a timely fashion.

The methods are applicable from exploration to development phases, with experienced operators able to adapt acquisition and instrumentation to the individual challenges faced; balancing resolution against more detailed molecular information to obtain the best possible datasets capable of being imported into reservoir modelling software alongside more conventional petrophysical data.