HR: 14:40h
AN: NS43A-05    [Abstracts]
TI: Structure classification methods applied to independent post-inversion physical-property models
AU: * Bedrosian, P A
EM: pbedrosian@usgs.gov
AF: US Geological Survey, Denver Federal Center Box 25046, Bldg 20, MS 964, Denver, CO 80225, United States
AB: The interpretation of geophysical models derived by inversion is a highly subjective part of any study. Our incomplete knowledge of the subsurface, the spatially-varying resolution of the models, and the non-uniqueness of the geophysical inverse problem make it difficult to objectively interpret physical-property models in terms of geologic structure. I present a classification approach to mapping geologic structure by combining independently- derived inverse models from a range of geophysical methods. The method employed is based solely on the statistical correlation of physical properties in a joint parameter space, and is independent of theoretical or empirical relations between the properties. Regions of high correlation between two or more physical properties are identified as separate classes, which can be defined using a variety of techniques and then reexamined in depth section. The spatial distribution of these classes, and the boundaries between them, are able to provide structural information (lithologic, tectonic, and hydrologic boundaries) often not evident in the individual models. This classification method is applied to several case studies on a range of scales including hydrologic assessment of earthen dams and fault characterization at the Dead Sea Transform and San Andreas Faults. The resulting structural sections are in good accordance with ground truth and supporting geophysics.
DE: 1808 Dams
DE: 3252 Spatial analysis (0500)
DE: 5199 General or miscellaneous
DE: 8015 Local crustal structure
SC: Near-Surface Geophysics [NS]
MN: 2007 Fall Meeting