GEOFLUID
In the Oil Industry, the importance of being able to recognize changes in fluid formation has pushed research primarily towards down-hole technologies, with the scope of giving more accurate reservoir evaluations.
However, even if accurate, downhole tools don’t permit real time analysis. Operational costs remain prohibitively high, not only due to the service provided but also due to the non-productive time of the rigs during down-hole logs.
In the past, standard gas analysis could not provide accurate and reliable information regarding formation fluids evaluation, thereby limiting the analysis to a qualitative gas composition inside the mud and also having a dependency on the drilling context.
Thanks to its proprietary Surface Logging technology, Geolog has specifically developed the GeoFluid system to address clients’ needs in this area:
- New degassing system, able to ensure constant conditions of mud analyzed (constant volume and constant temperature)
- New analyzer using a combination of the unique DUAL FID™ chromatograph and the latest technology in Mass Spectrometry
- Use of advanced techniques for gas ratio processing and formation fluid interpretation in real time.
GeoFluid can be used in combination with down hole technologies as support of interpretation and in some case can be the only available tool for fluid analysis (for example on ultra deep wells with high temperatures or under severe pressures where standard wireline tools cannot operate) or in the case of hole stability problems making wireline logs impossible or difficult to run.
The use of GeoFluid is particularly indicated in extended reach horizontal drilling where it is possible to follow the formation trends using the ratio analysis of the components.
The combination of Gas Chromatograph and Mass Spectrometer permits:
- a quantitative analysis of hydrocarbons composition of formation fluids and accurate interpretation of reservoir,
- pay zone delineation,
- to identify fluid contacts,
- to detect geochemical alteration,
- to improve down-hole logs,
- to optimize fluid sampling collection and analysis, reducing total operational costs.
Fluid Extractor
GeoFluid services include the new generation of Constant Volume Degasser (C.V.D) with Mud Heater for a quantitative extraction of fluids at constant, known and controlled flow and temperature, making fluid analysis not influenced by drilling parameters. Moreover, on deepwater wells, the mud return temperature can be very low to make impossible the detection of Hydrocarbon components. The use of Mud Heater permits to heat the mud and extract the heavier components, also when mud temperatures on surface are very low.
In order to evaluate the fraction of recycled hydrocarbons is normally suggested to use a second CVD in the pump suction line (using Geolog CVD, the extraction conditions remain the same).
Mass Spectrometer
Gas Chromatography and Mass Spectroscopy are combined to form a single method of analyzing mixtures of gasses.
The use of the mass spectrometer permits an increase in the measurement range of hydrocarbons up to C7, including aromatics and cyclic isomers of C6 and C7, in a rapid analysis cycle of only 60 seconds and with high speed analysis also for the heavier components.
Reservoir evaluation
Geolog utilizes proprietary techniques for the analysis and interpretation of fluid data acquired while drilling with the scope of elaborating Fluid Facies and composite logs (integrating fluid data with drilling data and geological information available from surface logging).
GeoFluid Engineers on site are responsible for the fluid analysis and (in co-operation with a central team of experts) provide a composite analysis giving Geolog clients the best information on formation fluid composition, fluid contacts, formation and pressure zone signature and multi-well analysis.
 |  |