HR: 13:55h
AN: NS43A-02 INVITED    [Abstracts]
TI: Joint inversion of crosshole radar and seismic traveltimes
AU: * Linde, N
EM: linde@aug.ig.erdw.ethz.ch
AF: Swiss Federal Institute of Technology, Institute of Geophysics, Schafmattstr. 30, Zurich, 8093, Switzerland
AU: Tryggvason, A
EM: ari.tryggvason@geo.uu.se
AF: Uppsala University, Department of Earth Sciences/Geophysics, Villav. 16, Uppsala, 752 36, Sweden
AU: Hubbard, S
EM: sshubbard@lbl.gov
AF: Lawrence Berkeley National Laboratory, Earth Sciences Division, 1 Cyclotron Road, ms 90-1116, Berkeley, CA 94720, United States
AU: Peterson, J
EM: jepeterson@lbl.gov
AF: Lawrence Berkeley National Laboratory, Earth Sciences Division, 1 Cyclotron Road, ms 90-1116, Berkeley, CA 94720, United States
AB: Joint inversion of different types of geophysical data collected at a common site can improve the determination of lithological boundaries. The structural approach to joint inversion, entailing common boundaries or gradients, offers a flexible way to invert diverse types of surface-based and/or crosshole geophysical data. The cross- gradients function was introduced as a means to construct models in which spatial changes in two models are parallel or anti-parallel. Inversion methods that use such structural constraints also provide estimates of non- linear and non-unique field-scale relationships between model parameters. We have developed an algorithm to invert jointly crosshole seismic and radar traveltimes for structurally similar models using an iterative non-linear traveltime tomography algorithm. A synthetic example demonstrates that the joint inversion better resolve lithological boundaries than the individual inversion. Inversion of field data collected in a saturated and unconsolidated environment show similar results. The robustness, relative simplicity, and apparent generality of the structural approach to joint inversion suggest that it may become a standard approach for jointly inverting geophysical and hydrological data when individually inverted models indicate structural similarity.
DE: 1829 Groundwater hydrology
DE: 1835 Hydrogeophysics
DE: 3260 Inverse theory
DE: 5102 Acoustic properties
DE: 5109 Magnetic and electrical properties (0925)
SC: Near-Surface Geophysics [NS]
MN: 2007 Fall Meeting