Accession Number:

ADA454934

Title:

Velocity Inversion by Coherency Optimization

Descriptive Note:

Corporate Author:

RICE UNIV HOUSTON TX DEPT OF MATHEMATICAL SCIENCES

Personal Author(s):

Report Date:

1989-08-01

Pagination or Media Count:

34.0

Abstract:

We introduce an approach to velocity and reflectivity estimation based on optimizing the coherence of multiple shot-gathering inversions of reflection seismograms. The resulting algorithm appears to avoid severe convergence difficulties reported for output nonlinear least- squares inversion. We describe in detail an algorithm appropriate for plane-layered acoustic models, using the convolutional approximation to the plane-wave p-tau seismogram. We give theoretical and numerical evidence that coherency optimization, as defined here, yields stable and reasonably accurate estimates of both velocity trend and reflectivity, by exploiting reflection phase moveout and amplitudes in a computationally efficient way. We demonstrate that the approach may be applied to field data by extracting velocity and reflectivity estimates from a Gulf of Mexico marine data set. Finally we explain briefly how the approach may be modified to determine elastic models and source parameters as well as to determine laterally heterogeneous models.

Subject Categories:

  • Seismology
  • Theoretical Mathematics
  • Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE