VSP traveltime inversion for linear inhomogeneity and elliptical anisotropy

Autor:	Michael A. Slawinski, Miro Powojowski, Chad J. Wheaton
Rok vydání:	2004
Předmět:	Wave propagation business.industry Field data Mathematical analysis Inversion (meteorology) Inverse problem Seismic wave Physics::Geophysics Geophysics Optics Geochemistry and Petrology Statistical analysis Anisotropy business Vertical seismic profile Geology
Zdroj:	GEOPHYSICS. 69:373-377
ISSN:	1942-2156 0016-8033
DOI:	10.1190/1.1707055
Popis:	To account for measured vertical seismic profiling (VSP) traveltimes, we study a velocity model described by three parameters. We assume that the velocity increases linearly with depth and is given in terms of parameters a and b, whereas the anisotropy is the result of elliptical velocity dependence and is given in terms of parameter χ. Using this model, we formulate an analytical expression for traveltime between a given source and a given receiver. This traveltime expression contains the three parameters that are present in the velocity model. To obtain the values of a, b, and χ, we use least‐squares fitting of this traveltime expression, with respect to measured traveltimes. This process of obtaining the parameters is exemplified by a study of traveltime data acquired with a two‐offset VSP in the Western Canada Basin. Having obtained a, b, and χ, we perform a statistical analysis, which shows good agreement between the field data and the modeled data. Furthermore, it shows that the elliptical velocity dependence, although small, is statistically significant.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::4b1c9dc96f4c5e34a14b32eaac546ad1 https://doi.org/10.1190/1.1707055 Zobrazit plný text záznamu