Amplitude anisotropy of shear-wave splitting and fluid detection in thin-layer reservoir
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Thin interbeds are typical reservoirs in eastern China. Thin layers and fractures bring huge challenge to fluid identification in anisotropic reservoir. This study focuses on thin-fractured reservoirs and amplitude attributes of shear-wave splitting, and consequently predicted fluid type in fractured reservoir based on the response of fast and slow S-waves to fluids. 3D HTI viscoelastic equation was employed to analyze amplitudes of split S-waves through fluid-filled and fractured media, including oil- and water-saturated synthetic models. Similar to velocity anisotropy, amplitude anisotropy was proposed to avoid the calculation of S-wave quality factor. Amplitude ratio and substation derived from amplitude anisotropy were used to identify fluid type. Example from the Luojia area of Shengli oilfield was used to demonstrate the effectiveness of the inversion method. Results show that amplitude ratio and amplitude subtraction are useful to distinguish fluids, while the former works better than the latter.
KeywordsHTI viscoelastic modeling Shear-wave splitting Amplitude anisotropy Fluid detection
This work was supported by the National Science and Technology Major Project (Grant No. 2017ZX05005-004-002), Fundamental Research Funds for the Central Universities (Grant No. 2652017415) and National Natural Science Foundation of China (Grant No. 41804132).
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflict of interest.
- Alford RM (1986) Shear data in the presence of azimuthal anisotropy: Dilley, Texas. In: SEG technical program expanded abstracts, pp 476–479. https://doi.org/10.1190/1.1893036
- Carcione JM (1990) Wave propagation in anisotropic linear viscoelastic media: theory and simulated wavefields. Geophys J Int 101(3):739–750. https://doi.org/10.1111/j.1365-246x.1990.tb05580.x CrossRefGoogle Scholar
- Carcione JM (2007) Wave fields in real media: wave propagation in anisotropic, anelastic, porous and electromagnetic media, Third edn. Elsevier, AmsterdamGoogle Scholar
- Jin Z, Papageorgiou G, Chapman M, Wu X (2016) Frequency-dependent AVO modeling for the estimation of gas saturation in a thin layer. In: SEG technical program expanded abstracts 2016, Society of exploration geophysicists, pp 521–526. https://doi.org/10.1190/segam2016-13609529.1
- Li XY (1997) Fractured reservoir delineation using multicomponent seismic data. Geophys Prospect 45(1):39–64. https://doi.org/10.1046/j.1365-2478.1997.3200262.x CrossRefGoogle Scholar
- Liu HP, Anderson DL, Kanamori H (1976) Velocity dispersion due to anelasticity; implications for seismology and mantle composition. Geophys J Int 47(1):41–58. https://doi.org/10.1111/j.1365-246x.1976.tb01261.x CrossRefGoogle Scholar
- Liu E, Crampin S, Queen J, Rizer W (1993) Velocity and attenuation anisotropy caused by microcracks and macrofractures in a multiazimuth reverse VSP. Can J Explor Geophys 29(1): 177–188. http://eap.bgs.ac.uk/PUBLICATIONS/PAPERS/P1993/1993eliusc.pdf
- Maultzsch S, Chapman M, Liu E, Li XY (2003) Modelling frequency-dependent seismic anisotropy in fluid-saturated rock with aligned fractures: implication of fracture size estimation from anisotropic measurements. Geophys Prospect 51(5):381–392. https://doi.org/10.1046/j.1365-2478.2003.00386.x CrossRefGoogle Scholar
- Queen J, Rizer W, DeMartini D (1992) Geophysical methods of fracture detection and estimation. In: SEG technical program expanded abstracts, vol 1991, pp 1642–1645. https://doi.org/10.1190/1.1888839
- Singleton S, Taner MT, Treitel S (2006) Q estimation using Gabor–Morlet joint time-frequency analysis techniques. In: SEG technical program expanded abstracts, vol 2006, pp 1610–1614. https://doi.org/10.1190/1.2369829
- Tillotson P, Sothcott J, Best AI, Chapman M, Li XY (2012) Experimental verification of the fracture density and shear-wave splitting relationship using synthetic silica cemented sandstones with a controlled fracture geometry. Geophys Prospect 60(3):516–525. https://doi.org/10.1111/j.1365-2478.2011.01021.x CrossRefGoogle Scholar