Estimativa de anisotropia local atraves de dados sinteticos das ondas P de walkaway VSP

Ellen Gomez Souza de Nazare, Ivan Psencik & J. Costa


Inversion scheme for the determination of anisotropy in a vicinity of a receiver situated in a borehole from the data obtained during a multiazimuth multiple-source offset VSP experiment is studied. The data consist of vertical components of slowness vectors and of polarization vectors of direct and reflected qP waves. We analyze the effects of the way of choice of a reference medium and of the wave normal on the results of inversion. We also study sensitivity of the inversion scheme to the number and orientation of profiles, to the number of sources along the profiles and to the number and type of waves considered. Study of the stability of the inversion scheme indicates which parameters of the medium can be recovered reliably and which cannot.

Expanded Abstracts of 9th Int. Congress of Brazilian Geophysical Society (Salvador) (CD-ROM), 315 (6 pp.), Brazilian Geophysical Society, 2005.
SW3D - main page of consortium Seismic Waves in Complex 3-D Structures .