Appraisal Analysis in Geophysical Inverse Problem: Tool for Image Interpretation and Survey Design

Tuesday, October 18, 2005 - 3:50pm - 4:40pm
EE/CS 3-180
Partha Routh (Boise State University)
Joint work with Doug Oldenburg.

Image appraisal in geophysical inverse problem can provide insight into the
resolving capability and uncertainty of estimates. Although a rigorous approach
to solve nonlinear appraisal analysis is still lacking but several methods have
been proposed in the past such as linearized Backus-Gilbert analysis, funnel
function method and nonlinear Backus-Gilbert formulation where forward problem
can be expressed as scattering series. In this talk I will discuss appraisal
analysis and how it can be used for image interpretation and survey design. In
image interpretation the goal is to quantify what part of model can be resolved
by the data and what parts are consequence of regularization operator? In
survey design the objective is to determine optimal survey parameters, such as
the position of sources/receivers and possibly frequencies in EM experiments,
that would provide better' model resolution in a region of interest. For both
of these problems we examine the resolution measure called point spread
function. The point spread function quantifies how an impulse in the true model
is observed in the inversion result and, hence, the goal is to adjust the
survey parameters so that the point spread function is as delta-like as
possible. This problem is solved as a nonlinear optimization problem with
constraints on the parameters. Examples from ray-based tomography and
controlled source electromagnetics will be presented.
MSC Code: