Velocity Inversion by Coherency Optimization

Abstract

We introduce an approach to velocity and reflectivity estimation based on optimizing the coherence of multiple shot-gather inversions of reflection seismograms. The resulting algorithm appears to avoid the severe convergence difficulties reported for output (nonlinear) least-squares inversion. We describe in detail an algorithm appropriate for the layered acoustic model, using the convolutional model of the plane-wave (ptau) seismogram. We give a theoretical analysis 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 also indicate how the approach may he modified to apply to laterally heterogeneous acoustic models, and (more briefly) to determination of elastic models and source parameters as well.

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Document Details

Document Type
Technical Report
Publication Date
May 01, 1988
Accession Number
ADA455248

Entities

People

  • William W. Symes

Organizations

  • Rice University

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Abstracts
  • Algorithms
  • Applied Mathematics
  • Heuristic Methods
  • Information Operations
  • Inversion
  • Mathematics
  • Operations Research
  • Optimization
  • Physical Properties
  • Plane Waves
  • Reflection
  • Reflectivity

Readers

  • Adaptive Control and Estimation with Uncertainty in Dynamic Systems.
  • Finite Element Method (FEM) for solving Partial Differential Equations (PDEs)
  • Wave Propagation and Nonlinear Chaotic Dynamics.