HR: 09:15h
AN: S21D-05    [Abstracts]
TI: Spatial Resolution of an Imaging System: Roles of Data-Acquisition Configuration and Imaging Propagators
AU: * Wu, R
EM: wrs@es.ucsc.edu
AF: University of California, Santa Cruz, 1156 High St., Earth Sciences/IGPP, Santa Cruz, CA 95064 United States
AU: Fehler, M
EM: fehler@lanl.gov
AF: Los Alamos Natl Laboratory, EES-4, MS D443, LANL,, Los Alamos, NM 87545 United States
AU: Xie, X
EM: xie@es.ucsc.edu
AF: University of California, Santa Cruz, 1156 High St., Earth Sciences/IGPP, Santa Cruz, CA 95064 United States
AU: Huang, L
EM: ljh@lanl.gov
AF: Los Alamos Natl Laboratory, EES-4, MS D443, LANL,, Los Alamos, NM 87545 United States
AB: Spatial resolution of an imaging system is formulated under the general frame of inversion theory. The spatial resolution operator (matrix) and its kernel (resolving kernel) are defined as a special case of the parameter resolution operator and its kernel, respectively. The formulation is derived for a general imaging system, including the data acquisition system and the imaging process. It is shown that there are many factors influencing the spatial resolution, including the acquisition aperture and geometry, overburden structures above the target area, and the accuracy of the propagators used in the imaging process. In the case of spatial resolution, the resolving kernel is reduced to the point spreading function (PSF) of the imaging system. We first discuss the theoretical limit of the resolution, which corresponds to an ideal, perfect reconstruction. In this case, the spatial resolution of the image depends only on the acquisition system configuration. Then we compare the resolutions (PSF) of imaging systems using different propagators in the imaging process: wave-theory based one-way propagators versus ray-theory based propagators (ray-Kirchhoff migration). Numerical examples are shown and compared with theoretical predictions. For imaging in heterogeneous media, such as random media with different scales of heterogeneities, we can clearly see the high-resolution feature of wave-theory based imaging methods compared with ray-theory approximated imaging methods.
DE: 7260 Theory and modeling
DE: 7200 SEISMOLOGY
DE: 7203 Body wave propagation
DE: 7218 Lithosphere and upper mantle
SC: Seismology [S]
MN: 2004 AGU Fall Meeting