Browse

Refraction traveltime tomography using damped monochromatic wavefield

DC Field Value Language
dc.contributor.authorPyun, Sukjoon-
dc.contributor.authorShin, Changsoo-
dc.contributor.authorMin, Dong-Joo-
dc.contributor.authorHa, Taeyoung-
dc.date.accessioned2009-08-03T23:29:20Z-
dc.date.available2009-08-03T23:29:20Z-
dc.date.issued2005-03-22-
dc.identifier.citationGeophysics, 70, U1-U7en
dc.identifier.issn0016-8033-
dc.identifier.urihttps://hdl.handle.net/10371/6108-
dc.description.abstractFor complicated earth models, wave-equation–based
refraction-traveltime tomography is more accurate than
ray-based tomography but requires more computational
effort. Most of the computational effort in traveltime
tomography comes from computing traveltimes
and their Fr´echet derivatives, which for ray-based
methods can be computed directly. However, in most
wave-equation traveltime-tomography algorithms, the
steepest descent direction of the objective function
is computed by the backprojection algorithm, without
computing a Fr ´echet derivative directly.
We propose a new wave-based refraction-traveltime–
tomography procedure that computes Fr´echet derivatives
directly and efficiently. Our method involves solving
a damped-wave equation using a frequency-domain,
finite-element modeling algorithm at a single frequency
and invoking the reciprocity theorem. A damping factor,
which is commonly used to suppress wraparound
effects in frequency-domain modeling, plays the role
of suppressing multievent wavefields. By limiting the
wavefield to a single first arrival, we are able to extract
the first-arrival traveltime from the phase term
without applying a time window. Computing the partial
derivative of the damped wave-equation solution
using the reciprocity theorem enables us to compute
the Fr ´echet derivative of amplitude, as well as that of
traveltime, with respect to subsurface parameters. Using
the Marmousi-2 model, we demonstrate numerically
that refraction traveltime tomography with large-offset
data can be used to provide the smooth initial velocity
model necessary for prestack depth migration.
en
dc.description.sponsorshipThis work was financially supported by the National Laboratory
Project of the Ministry of Science and Technology
and the Brain Korea 21 project of the Ministry of Education.
We are also grateful to Prof. K. J. Marfurt of the University
of Houston and Dr. M. Schoenberger for editing our
manuscript.
en
dc.language.isoenen
dc.publisherSociety of Exploration Geophysicists (SEG)en
dc.subjectWavefielden
dc.subjecttomographyen
dc.subjecttraveltimeen
dc.subjectdamped monochromatic wavefileden
dc.titleRefraction traveltime tomography using damped monochromatic wavefielden
dc.typeArticleen
dc.contributor.AlternativeAuthor편석준-
dc.contributor.AlternativeAuthor신창수-
dc.contributor.AlternativeAuthor민동주-
dc.contributor.AlternativeAuthor하태영-
dc.identifier.doi10.1190/1.1884829-
Appears in Collections:
College of Engineering/Engineering Practice School (공과대학/대학원)Dept. of Energy Systems Engineering (에너지시스템공학부)Journal Papers (저널논문_에너지시스템공학부)
Files in This Item:
  • mendeley

Items in S-Space are protected by copyright, with all rights reserved, unless otherwise indicated.

Browse