Seismic waves in inhomogeneous weakly anisotropic media (GA CR, 16-05237S)
Seismic anisotropy, mostly weak, is an omnipresent property of the Earth’s interior. Although weak, it influences seismic wave propagation considerably, especially S-wave propagation. It also affects applicability of approximate high-frequency asymptotic methods, such as the broadly used ray method. In case of P waves, weak anisotropy leads to a considerable simplification of formulae following from standard high-frequency asymptotics for anisotropic media. In case of S waves, the standard high-frequency methods become even inapplicable. S waves in weakly anisotropic inhomogeneous media do not propagate separately, they interact mutually. To describe the S-wave coupling, modified procedures like the coupling ray theory should be used. Our team performs such studies. We continue in designing and testing sufficiently accurate and reliable procedures, describing S-wave coupling and including P-wave propagation, which can be used for solving variety of forward and inverse problems.
Principal researcher: Ivan Pšenčík
(Department of Seismology, IG CAS)
Joint researcher: Vlastislav Červený (Department of Geophysics, Faculty of Mathematics and Physics, Charles University)
Team members: Bohuslav Růžek (Department of Seismology, IG CAS), Luděk Klimeš, Petr Bulant a Václav Bucha (Department of Geophysics, Faculty of Mathematics and Physics, Charles University)
Bucha, V., 2017. Kirchhoff prestack depth migration in simple models with differently rotated elasticity tensor: orthorhombic and triclinic anisotropy. J. seism. Explor., 26, 1-24.
Bulant, P., & Klimeš, L., 2018. Comparison of the anisotropic-ray-theory rays and anisotropic common S-wave rays with the SH and SV reference rays in a velocity model with a split intersection singularity. Stud. geophys. geod., 62, 57-79.
Bulant, P., & Klimeš, L., 2019. 3-D velocity models – transformation from general to natural splines. Stud. geophys. geod., 63, 143-152
Červený, V., & Pšenčík, I., 2017. Elementary Green function as an integral superposition of Gaussian beams in inhomogeneous anisotropic layered structures in Cartesian coordinates. Geophys.J.Int., 210, 561-569.
Farra, V., & Pšenčík, I., 2017. Weak-anisotropy moveout approximations for P waves in homogeneous TOR layers. Geophysics, 82, WA23–WA32.
Farra, V., & Pšenčík, I., 2019. Reflection moveout approximation for a P-SV wave in a moderately anisotropic homogeneous VTI layer. Geophysics, 84, C75-C83.
Farra, V., & Pšenčík, I., 2018. Reflection moveout approximation for a P-SV wave in a moderately anisotropic homogeneous DTI layer. J. Appl. Geophys., 159, 690-696.
Klimeš, L., 2016. Determination of the reference symmetry axis of a generally anisotropic medium which is approximately transversely isotropic. Stud. geophys. geod., 60, 391-402.
Klimeš, L., 2018. Frequency-domain ray series for viscoelastic waves with a non-symmetric stiffness matrix. Stud. geophys. geod., 62, 261-271.
Klimeš, L., 2018. Reference transversely isotropic medium approximating a given generally anisotropic medium. Stud. geophys. geod., 62, 255-260.
Klimeš, L., 2018. Superpositions of Gaussian beams and column Gaussian packets in heterogeneous anisotropic media. Geophys. J. int., 215, 1739-1746.
Klimeš, L., 2019. Calculation of the amplitudes of elastic waves in anisotropic media in Cartesian or ray-centred coordinates. Stud. geophys. geod., 63, 10.1007/s11200-018-1251-7.
Klimeš, L., 2019. Comparison of ray-matrix and finite-difference methods in a simple 1-D velocity model. Stud. geophys. geod., 63, 10.1007/s11200-018-1152-9.
Pšenčík, I., & Farra, V., 2017. Reflection moveout approximations for P-waves in a moderately anisotropic homogeneous tilted transverse isotropy layer. Geophysics, 82, C175-C185.
Pšenčík, I., Růžek, B., Lokajíček, T., & Svitek, T., 2018. Determination of rock–sample anisotropy from P– and S–wave traveltime laboratory measurements. Geophys.J.Int., 214, 1088–1104.
Publication in research reports
Bucha, V., 2016. Kirchhoff prestack depth migration in simple orthorhombic and triclinic models with differently rotated elasticity tensor: comparison with zero-offset travel-time perturbations. Seismic Waves in Complex 3-D Structures, 26, 81-102 (ISSN 2336-3827, online at http://sw3d.cz).
Bucha, V., 2017. Comparison of Fourier pseudospectral method seismograms and ray-theory travel times in a simple triclinic model. Seismic Waves in Complex 3-D Structures, 27, 69-82 (ISSN 2336-3827, online at http://sw3d.cz).
Bucha, V., 2018. Kirchhoff prestack depth scalar migration in a simple triclinic velocity model for three–component P, S and converted waves. Seismic waves in Complex 3-D Structures, 28, 61-84 (ISSN 2336-3827, online at http://sw3d.cz).
Bucha, V., 2018. Kirchhoff prestack depth scalar migration of complete wave field in a simple inhomogeneous weakly anisotropic velocity model: preliminary tests. Seismic waves in Complex 3-D Structures, 28, 85-96 (ISSN 2336-3827, online at http://sw3d.cz).
Bucha, V., 2018. Comparison of Fourier pseudospectral method seismograms and ray– theory travel times in a simple triclinic model: revealed direct wave. Seismic waves in Complex 3-D Structures, 28, 97-112 (ISSN 2336-3827, online at http://sw3d.cz).
Bulant, P., 2016. Feasibility of anisotropic inversion based on P-wave travel-time curves. Seismic Waves in Complex 3-D Structures, 26, 103-122 (ISSN 2336-3827, online at http://sw3d.cz).
Červený, V., & Pšenčík, I., 2016. Green function as an integral superposition of Gaussian beams in inhomogeneous anisotropic layered structures in Cartesian coordinates. Seismic Waves in Complex 3-D Structures, 26, 131-153 (ISSN 2336-3827, online at http://sw3d.cz).
Farra, V., & Pšenčík, I., 2017. Reflection moveout approximation for converted P-SV wave in a moderately anisotropic homogeneous VTI layer. Seismic waves in Complex 3-D Structures, 27, 51-58 (ISSN 2336-3827, online at http://sw3d.cz).
Farra, V., & Pšenčík, I., 2018. Reflection moveout approximation in layered media of arbitrary moderate anisotropy. Seismic waves in Complex 3-D Structures, 28, 45-60 (ISSN 2336-3827, online at http://sw3d.cz).
Jakobsen, M., Pšenčík, I., Iversen, E., & Ursin, B., 2017. On the parameterization of seismic anisotropy for ray-Born inversion. Seismic waves in Complex 3-D Structures, 27, 37-49 (ISSN 2336-3827, online at http://sw3d.cz).
Klimeš, L., 2016. Reference transversely isotropic medium approximating a given generally anisotropic medium. Seismic Waves in Complex 3-D Structures, 26, 155-158 (ISSN 2336-3827, online at http://sw3d.cz).
Klimeš, L., 2017. Representation theorem for viscoelastic waves with a non-symmetric stiffness matrix. Seismic Waves in Complex 3-D Structures, 27, 93-96 (ISSN 2336-3827, online at http://sw3d.cz).
Klimeš, L., 2017. Rotationally invariant viscoelastic medium with a non-symmetric stiffness matrix. Seismic Waves in Complex 3-D Structures, 27, 97-103 (ISSN 2336-3827, online at http://sw3d.cz).
Pšenčík, I., & Farra, V., 2016. Weak-anisotropy moveout approximations for P waves in homogeneous TTI layers. Seismic Waves in Complex 3-D Structures, 26, 61-80 (ISSN 2336-3827, online at http://sw3d.cz).
Pšenčík, I., 2017. Transformation rules for weak-anisotropy parameters. Seismic waves in Complex 3-D Structures, 27, 59–68 (ISSN 2336-3827, online at http://sw3d.cz).
Pšenčík, I., Růžek, B., Lokajíček, T., & Svitek, T., 2017. Determination of rock–sample anisotropy from P– and S–wave traveltimes. Seismic waves in Complex 3-D Structures, 27, 15–35 (ISSN 2336-3827, online at http://sw3d.cz).
Pšenčík, I., Růžek, B., & Jílek, P., 2018. Practical concept of arbitrary anisotropy applied in traveltime inversion of simulated P–wave VSP data. Seismic waves in Complex 3-D Structures, 28, 9-44 (ISSN 2336-3827, online at http://sw3d.cz).
Pšenčík, I., & Wcislo, M., 2018. SH–wave reflection/transmission coefficients in an isotropic, weakly attenuating media. Seismic waves in Complex 3-D Structures, 28, 113-134 (ISSN 2336-3827, online at http://sw3d.cz).
Růžek, B., & Pšenčík, I., 2016. P-wave VSP traveltime inversion in weakly and moderately anisotropic media. Seismic Waves in Complex 3-D Structures, 26, 17-59 (ISSN 2336-3827, online at http://sw3d.cz).
Wcislo, M., & Pšenčík, I., 2017. Seismic waves in inhomogeneous, weakly dissipative, anisotropic media; preliminary tests with P waves. Seismic waves in Complex 3-D Structures, 27, 69–82 (ISSN 2336-3827, online at http://sw3d.cz).
Wcislo, M., 208. Effects of attenuation, velocity and density on SH–wave reflection/ transmission coefficients in isotropic, weakly attenuating media. Seismic waves in Complex 3-D Structures, 28, 135-168 (ISSN 2336-3827, online at http://sw3d.cz).
Presentations at conferences and seminars
Bulant, P., 2018. Feasibility of anisotropic inversion based on P-wave travel–time curves. 18IWSA, Jeruzalem, Nov.4-11, 2018, https://iwsa-18.herokuapp.com.
Farra, V., & Pšenčík, I. 2018. Moveout approximation for a converted wave in a moderately anisotropic homogeneous DTI layer. 18IWSA, Jeruzalem, Nov.4-11, 2018, https://iwsa-18.herokuapp.com.
Farra, V., & Pšenčík, I., 2018. P-wave reflection moveout in a layered medium of moderate anisotropy. 18IWSA, Jeruzalem, Nov.4-11, 2018, https://iwsa-18.herokuapp.com.
Jakobsen, M., Pšenčík, I., Iversen, E., & Ursin, B., 2017. On the parameterization of seismic anisotropy in linearized waveform inversion: The HTI case. 79th EAGE Conference and Exhibition, Paris, France, June, 12-15, 2017.
Klimeš, L., 2018. Frequency-domain ray series for viscoelastic waves with a non-symmetric stiffness matrix. 18IWSA, Jeruzalem, Nov.4-11, 2018, https://iwsa-18.herokuapp.com.
Klimeš, L., 2018. Representation theorem for viscoelastic waves with a non-symmetric stiffness matrix. In: Kolman, R., Berezovski, A., Kruisova, A. (eds.): The 2nd International Conference on Advanced Modelling of Wave Propagation in Solids, Institute of Thermomechanics ASCR, Prague, Czech Republic, ISBN 978-80-87012-67-3, pp. 69-70.
Klimeš, L. & Bulant, P., 2017. Interpolation of the coupling-ray-theory Green function within ray cells. In: Expanded Abstracts of 15th Int. Congress of the Brazilian Geophysical Society (Rio de Janeiro 2017) (CD-ROM),8332017013112395 (4 pp.), Brazilian Geophysical Society, ISSN 2175-4551.
Klimeš, L. & Bulant, P., 2017. Prevailing-frequency approximation of the coupling ray theory for S waves along the SH and SV reference rays.In: Expanded Abstracts of 15th Int. Congress of the Brazilian Geophysical Society (Rio de Janeiro 2017) (CD-ROM), 8332017013118262 (6 pp.), Brazilian Geophysical Society, ISSN 2175-4551.
Pšenčík, I., & Farra, V., 2016. P-wave weak-anisotropy moveout approximations for anisotropy of arbitrary symmetry: TTI case. 17th International workshop on seismic anisotropy, USA.
Pšenčík, I., & Růžek, B., 2016. Inversion of P-wave VSP traveltimes in homogeneous weakly and moderately anisotropic media. 17th International workshop on seismic anisotropy, USA.
Pšenčík, I., & Růžek, B., 2017. Inversion of P-wave VSP traveltimes in homogeneous weakly and moderately anisotropic media. In: Expanded Abstracts of 15th Int.Congress of the Brazilian Geophysical Society (Rio de Janeiro 2017) (CD-ROM), 8872017013010501 (3 pp.), Brazilian Geophysical Society, ISSN 2175-4551.
Pšenčík, I., & Růžek, B., 2018. Inversion of P-wave VSP traveltimes in anisotropic media. In: Kolman, R., Berezovski, A., Kruisova, A. (eds.): The 2nd International Conference on Advanced Modelling of Wave Propagation in Solids, Institute of Thermomechanics ASCR, Prague, Czech Republic, ISBN 978-80-87012-67-3, pp. 103-104.
Růžek, B., & Pšenčík, I., 2016. Inversion of P-wave traveltimes from a VSP experiment in a homogeneous anisotropic medium. EGU conference, Vienna,EGU2016-12618.
Růžek, B., & Pšenčík, I., 2016. P-wave traveltime inversion in homogeneous weakly or moderately anisotropic media: a study using synthetic data for a typical VSP measurement. ADLAS workshop, Praha 22.-25.5.2016.
Růžek, B., & Pšenčík, I., 2016. Inversion of P-wave traveltimes from a VSP experiments in moderately anisotropic media. ESC conference Trieste, 8.9.2016, ESC2016-117.
Růžek, B., & Pšenčík, I., 2018. Inversion of VSP P-wave traveltimes in homogeneous and inhomogeneous anisotropic media. ESC General Asseembly, ESC-S10-198, Valletta.
Růžek, B., Pšenčík, I., & Horálek, J., 2018. Local Earthquake Tomography using the Weak Anisotropy concept. Geophysical Research Abstracts, 20, EGU2018-7169-2, EGU General Assembly 2018.
Wcislo, M., & Pšenčík, I., 2017. Seismic waves in inhomogeneous, weakly dissipative, anisotropic media. Doktorandský den, GFÚ AV ČR, May 31, 2017.
Wcislo, M., & Pšenčík, I., 2018. SH-wave reflection coefficient in an isotropic, weakly attenuating medium. 18IWSA, Jeruzalem, Nov.4-11, 2018, https://iwsa-18.herokuapp.com.