Determination of rock-sample anisotropy from P- and S-wave traveltime inversion

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985530%3A_____%2F18%3A00490923" target="_blank" >RIV/67985530:_____/18:00490923 - isvavai.cz</a>

Nalezeny alternativní kódy

RIV/67985831:_____/18:00490923

Výsledek na webu

<a href="http://dx.doi.org/10.1093/gji/ggy173" target="_blank" >http://dx.doi.org/10.1093/gji/ggy173</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1093/gji/ggy173" target="_blank" >10.1093/gji/ggy173</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Determination of rock-sample anisotropy from P- and S-wave traveltime inversion

Popis výsledku v původním jazyce

We determine anisotropy of a rock sample from laboratory measurements of P- and S-wave traveltimes using weak-anisotropy approximation and parametrization of the medium by a special set of anisotropy parameters. For the traveltime inversion, we use first-order velocity expressions in the weak-anisotropy approximation, which allow to deal with P and S waves separately. Each wave is described by 15 anisotropy parameters, 9 of which are common for both waves. The parameters allow an approximate construction of separate P- or common S-wave phase-velocity surfaces. Common S-wave concept is used to simplify the treatment of S waves. In order to obtain all 21 anisotropy parameters, P- and S-wave traveltimes must be inverted jointly. The proposed inversion scheme has several advantages. As a consequence of the use of weak-anisotropy approximation and assumed homogeneity of the rock sample, equations used for the inversion are linear. Thus, the inversion procedure is non-iterative. In the approximation used, phase and ray velocities are equal in their magnitude and direction. Thus, analysis whether the measured velocity is the ray or phase velocity is unnecessary. Another advantage of the proposed inversion scheme is that, thanks to the use of the common S-wave concept, it does not require identification of S-wave modes. It is sufficient to know the two S-wave traveltimes without specification, to which S-wave mode they belong. The inversion procedure is tested first on synthetic traveltimes and then used for the inversion of traveltimes measured in laboratory. In both cases, we perform first the inversion of P-wave traveltimes alone and then joint inversion of P-and S-wave traveltimes, and compare the results.

Název v anglickém jazyce

Determination of rock-sample anisotropy from P- and S-wave traveltime inversion

Popis výsledku anglicky

We determine anisotropy of a rock sample from laboratory measurements of P- and S-wave traveltimes using weak-anisotropy approximation and parametrization of the medium by a special set of anisotropy parameters. For the traveltime inversion, we use first-order velocity expressions in the weak-anisotropy approximation, which allow to deal with P and S waves separately. Each wave is described by 15 anisotropy parameters, 9 of which are common for both waves. The parameters allow an approximate construction of separate P- or common S-wave phase-velocity surfaces. Common S-wave concept is used to simplify the treatment of S waves. In order to obtain all 21 anisotropy parameters, P- and S-wave traveltimes must be inverted jointly. The proposed inversion scheme has several advantages. As a consequence of the use of weak-anisotropy approximation and assumed homogeneity of the rock sample, equations used for the inversion are linear. Thus, the inversion procedure is non-iterative. In the approximation used, phase and ray velocities are equal in their magnitude and direction. Thus, analysis whether the measured velocity is the ray or phase velocity is unnecessary. Another advantage of the proposed inversion scheme is that, thanks to the use of the common S-wave concept, it does not require identification of S-wave modes. It is sufficient to know the two S-wave traveltimes without specification, to which S-wave mode they belong. The inversion procedure is tested first on synthetic traveltimes and then used for the inversion of traveltimes measured in laboratory. In both cases, we perform first the inversion of P-wave traveltimes alone and then joint inversion of P-and S-wave traveltimes, and compare the results.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10507 - Volcanology

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2018

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Geophysical Journal International

ISSN

0956-540X

e-ISSN

—

Svazek periodika

214

Číslo periodika v rámci svazku

2

Stát vydavatele periodika

GB - Spojené království Velké Británie a Severního Irska

Počet stran výsledku

17

Strana od-do

1088-1104

Kód UT WoS článku

000448238600019

EID výsledku v databázi Scopus

2-s2.0-85052631313