Geometrical characteristics in anisotropic media
- Alexey Stovas (NTNU, Norway) | Yuriy Roganov (Tesseral Inc., Ukraine) | Vyacheslav Roganov (Glushkov Institute, Ukraine.)
- Document ID
- Society of Exploration Geophysicists
- SEG International Exposition and Annual Meeting, 15-20 September, San Antonio, Texas, USA
- Publication Date
- Document Type
- Conference Paper
- 2019. Society of Exploration Geophysicists
- Anisotropy, 3D, Wave propagation
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- 11 since 2007
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There are several important characteristics of wave propagation in anisotropic media such as singularity directions (acoustic axes) and caustics. There is an extensive literature devoted to these features (Musgrave, 1970; Shuvalov and Every, 2000; Cerveny, 2004; Norris, 2004, Vavrycuk, 2003; 2005, Roganov and Stovas, 2010; 2011). The singularity directions result in anomalies of polarization vectors (Alshits and Lothe, 2004) and complications in ray tracing (Vavrycuk, 2003). Caustics (Dellinger, 1991) shape the triplication zones (multivalued traveltime function) and result in a specific phase shift which is associated with so called KMAH index (Klimes, 1997; Bakker, 1998). The phase-to-group correction angles (Stovas et al., 2018) can also be considered as characteristic of anisotropic medium.
In our paper, we propose a new characteristic that can be used to analyse both of these features which is known as an enhancement factor (Jaeken and Cottenier, 2016). We illustrate this factor on elastic and acoustic orthorhombic models.
Presentation Date: Monday, September 16, 2019
Session Start Time: 1:50 PM
Presentation Time: 2:40 PM
Location: Poster Station 7
Presentation Type: Poster
|File Size||3 MB||Number of Pages||5|
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