We believe that it's the responsibility of the geoscientist to translate results in something useful to engineers and other geosciences, not the other way around. For instance, seismic attributes volumes derived from inversion, curvature or amplitude/velocity anisotropy must be translated into volumes than can be understood and used by other disciplines such as porosity, permeability, facies, fracture density, fracture permeability anisotropy, and stress. Petrophysical calculations must be regionally calibrated to ensure meaningful geological mapping and volumetric calculations.
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Providing this kind of seismic insight requires careful calibration with multiple data types and close collaboration with all geoscientist and engineers involved. We then build geological grids that contain all the calibrated information that are ready to support exploration and development decisions that may even include flow simulation.
Petrophysical calibration philosophy
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Emphasizes preservation of geological trends during the normalization process.
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Uses core data as the ultimate quantitative data for calibration using a statistical approach.
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Aims to honor other independent data like production, lithology trends, and mud logs.
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Uses quality control maps at different stages to ensure reasonable results.
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Applies the right level of complexity for the question asked.
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Searches for useful, not perfect solutions.
Matrix calibration philosophy
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Emphasizes the definition of facies flags that are related to production drivers.
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Emphasizes the use of inverted seismic attributes (AI and Vp/Vs ratio) or frequency decomposition attributes extracted along well paths (verticals and horizontals) for identification of facies in multidimensional crossplots of elastic properties.
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Emphasizes the use of facies that can be detected at seismic scale.
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Statistical in nature: does not attempt to use inverted seismic attributes to match detailed variations along well paths but rather larger scale variability
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Results are probabilistic and include estimates of error and reliability useful for risk assessment.
Fracture calibration philosophy
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Separates the calibration depending on their origin (joints vs faults), scale, and flow properties.
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Uses any fracture information available from outcrops, image logs, mud gas shows, cross-dipole sonics or other log indicators, microseismic, and production data.
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Dynamic fracture apertures in continuous and discrete models are adjusted to honor well tests and production data.
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Takes into account the state of stress in determination of possible flow properties.
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Statistical in nature: does not attempt to match 3D seismic fracture attributes to detailed fracture variations along well paths or particular microseismic events.
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Assumes that statistics of fracture orientations is scale invariant.
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The calculators we feature here are just an example of the kind of multidisciplinary work we do in order to get a comprehensive picture of the main factors that affect fluid flow in fracture models.
