Method and apparatus for characterizing azimuthal anisotropy using statistical moments
AssigneeCgg Services SAS
InventorBenjamin Roure
Life of this patent
Estimating the term…
Abstract
A method for evaluating anisotropy parameters using statistical moments calculates second and third central moments using reflectivity values associated with pairs of incidence and azimuth angles. The method further determines tangential and normal weaknesses for the location using the calculated second and third central moments for different incident angles. Linear and non-linear inversions of statistical moments are used to estimate the fracture weaknesses, anisotropic gradient (biased and unbiased), anellipticity variation and unambiguous orientation.
Claims20
A method evaluating anisotropy parameters using statistical moments, the method comprising:
- obtaining seismic data considered as reflectivity values associated with pairs of incidence, θ, and azimuth φ angles related to an explored formation;
- calculating second central moment, m2(θ), for at least two different incident angles and third central moment, m3(θ), for at least one incident angle at a location within the explored formation using the reflectivity values;
- determining tangential and normal weaknesses for the location using the calculated second and third central moments, and
- planning hydrocarbon extraction using fracture characterization based on the determined tangential and normal weaknesses.
An apparatus for evaluating anisotropy parameters from seismic data using statistical moments, the apparatus comprising:
- an interface configured to obtain seismic data considered as reflectivity values associated with pairs of incidence, θ, and azimuth φ angles related to an explored formation;
- and
- a data processing unit including one or more processors, the data processing unit being configured
- to calculate second central moment, m2(θ), for at least two different incident angles and a third m3(θ) central moment for at least one incident angle at a location within the explored formation using the reflectivity values,
- to determine tangential and normal weaknesses for the location using the calculated second and third central moments, and
- to plan hydrocarbon extraction using fracture characterization based on the determined tangential and normal weaknesses.
A computer readable recording medium non-transitorily storing executable codes which when executed by a computer make the computer perform a method for evaluating anisotropy parameters from seismic data using statistical moments, the method comprising:
- obtaining seismic data considered as reflectivity values associated with pairs of incidence, θ, and azimuth φ angles related to an explored formation;
- calculating second central moment m2(θ) for at least two different incident angles and a third m3(θ) central moment for at least one incident angle at a location within the explored formation using the reflectivity values;
- determining tangential and normal weaknesses for the location using the calculated second and third central moments;
- and
- planning hydrocarbon extraction using fracture characterization based on the determined tangential and normal weaknesses.
Dependencies are inferred from the claim text.