This cased-hole interpretation model is designed for saturation analysis of a single well based on sigma logs from any supplier. Oil saturation can be determined in the presence of saline formation waters. Gas saturation can be determined under almost any conditions.
Features
• Saturation interpretation of any formation sigma data • Standard volumetric analysis or an adaptation of the
Chevron variable matrix model
• Inclusion of open-hole porosity and clay volume analyses
• Stand-alone analysis using porosity and clay indicators from cased-hole monitoring tools or any available source • Determines volume of hydrocarbons produced from the
reservoir and allows estimates of remaining reserves • Enhances reservoir production knowledge
• Allows better understanding of hydrocarbon drainage efficiency from the reservoir
• Identifies potential hydrocarbon production zones that have not been drained or were bypassed or previously undiscovered
• Pinpoints changing oil/water and gas/oil contacts through time lapse monitoring
• Finds flooded or swept zones
Associated Answer Products and Pre-Processing Software
• Pulse-height spectral gain stabilization and processing, plus environmental corrections (TMDLRL)
• CarbOxSat™ model – similar model for saturation analysis of neutron decay logs
• TripleSat™ model – similar family of models utilizing both carbon/oxygen and neutron decay logs for use where three fluids are present in the reservoir
Track 1 indicates the amount of sand and shale by volume, along with the effective porosity. Track 2 is a porosity overlay track indicating hydrocarbon crossover. Track 3 shows sigma water apparent and sigma solids apparent. Track 4 shows an envelope of sigma wet and sigma hydrocarbon with sigma intrinsic in between, indicating the hydrocarbon. Track 5 indicates the total hydrocarbon saturation, and Track 6 shows total porosity, effective porosity, the effective volume of water, and the volume of hydrocarbon.
HAL11409
Inputs Clay volume, total porosity, effective porosity, environmentally corrected intrinsic sigma
Outputs
Individual and combined clay volume, total porosity, effective porosity, capture-ratio porosity, inelastic ratio porosity, hydrocarbon volume, total and effective hydrocarbon saturation, water volume
Reservoir Evaluation Services
2-49
CarbOxSat™ Model
This interpretive model is specifically designed for saturation analysis of a single well based on Halliburton carbon/oxygen (C/O) logs. The CarbOxSat™ model is used for interpreting oil saturation in reservoirs where formation water salinity is fresh, mixed, or unknown.
Features
• Saturation interpretation of all Halliburton formation carbon/oxygen data
• Halliburton’s lithology compensated Delta-C/O or traditional overlay method
• Inclusion of open-hole porosity and clay volume analyses
• Stand-alone analysis using porosity and clay indicators from cased-hole monitoring tools or any available source • Determines volume of hydrocarbons produced from the
reservoir and allows estimates of remaining reserves • Enhances reservoir production knowledge
• Allows better understanding of hydrocarbon drainage efficiency from the reservoir
• Identifies potential hydrocarbon production zones that have not been drained or were bypassed or previously undiscovered
• Pinpoints changing oil/water and gas/oil contacts through time lapse monitoring
• Finds flooded or swept zones
Associated Answer Products and Pre-Processing Software
• Pulse-height spectral gain stabilization and processing (RMTERL)
• Multi-pass stacking (RMTEAVG) • Environmental corrections (RMTECOR)
• SigmaSat™ model – similar model for saturation analysis of neutron decay logs
• TripleSat™ model – similar family of models utilizing both carbon/oxygen and neutron decay logs for use where three fluids are present in the reservoir
Track 1 contains the open-hole neutron and density porosity curves, as well as the gamma ray curve. Track 2 contains the cased-hole porosity indicators of a pseudo-density curve from the inelastic ratio, and a pseudo-neutron porosity from the capture ratio. Track 3 contains the delta-C/O envelope indicating the C/O interpretation. Track 5 shows the total hydrocarbon saturation, and Track 6 is a volumetrics track containing the volume of shale, effective porosity, and the bulk volume of water to provide water and hydrocarbon saturation.
HAL11768
Inputs Clay volume, total porosity, effective porosity, environmentally corrected carbon/oxygen and calcium/silica ratios
Outputs
Individual and combined clay volume, total porosity, effective porosity, capture-ratio porosity, inelastic ratio porosity, volume of oil, total and effective oil saturations, water volumes
TripleSat™ Model
This unique interpretation model is specifically designed for use with Halliburton’s reservoir monitoring tools. The TripleSat™ model employs a combination of C/O and sigma measurements and is used to calculate saturation when three fluids are present in the reservoir.
Features
• Utilizes simultaneously-recorded sigma and C/O measurements
• Provides more accurate interpretation in oil producing reserves where steam or gas is present
• Contains selectable sets of equations that can be optimized for one of the following:
– Steamflood
– Oil drainage from gas cap – Gasflood
– Sea waterflood
• Allows additional optimizations to be readily
constructed, some using a Halliburton adaptation of the Chevron gas correction to carbon/oxygen logs
• Permits inclusion of open-hole porosity and clay volume analyses
• Allows stand-alone analysis using porosity and clay indicators from cased-hole monitoring tools or any available source
• Allows accurate interpretation in reservoirs that have gas cap development or are under steamflood or gasflood • Permits interpretation in reservoirs with retrograde
condensate production
Associated Answer Products and Pre-Processing Software
• SigmaSat™ model – neutron decay time saturation analysis
• CarbOxSat™ model – carbon/oxygen saturation analysis
KernSat Interpretation Example. This well located in Kern County, California in the Kern River Field, is in an active steamflood
hydrocarbon recovery project. This log is an example of our customized interpretation model KernSat. Track 4 of the example displays the computed oil saturation (shaded in green) and the gas saturation (shaded in red). These saturations were computed using a combination of carbon-oxygen ratio and formation sigma. Track 3 displays the carbon-oxygen and the calcium-silicon ratio curves. The green shading between the two curves indicates hydrocarbons in the formation. Also displayed in the track are the natural gamma ray measurement and the simultaneous recorded formation sigma. Tracks 1 and 2 display a comparison of the open-hole density and neutron porosities and the porosity ratio indicators measured by the RMT Elite™ analysis. Track 1 is the open-hole density neutron porosity. Steam measured in the formation at the time of the log is indicated by the gray shading between the curves. Tracks 2 displays the inelastic and capture ratios measured from the RMT Elite analysis. The red shading indicates the current location of steam in the reservoir. This example indicates that the steam chest has expanded when compared to the original formation contacts. The depth track recorded at the far left side of the log displays water flow measured by the RMT Elite analysis outside the casing.
HAL9180
Inputs
Clay volume, total porosity, effective porosity, environmentally corrected carbon-oxygen and calcium-silica ratios, environmentally corrected sigma