HR: 16:50h
AN: S44A-03    [Abstracts]
TI: Formal integration of controlled-source and passive seismic data: Utilization of the CD-ROM experiment
AU: * Rumpfhuber, E
EM: eva@geo.utep.edu
AF: University of Texas at El Paso Department of Geological Sciences, 500 W. University Ave., El Paso, TX 79902 United States
AU: Keller, G R
EM: keller@geo.utep.edu
AF: University of Texas at El Paso Department of Geological Sciences, 500 W. University Ave., El Paso, TX 79902 United States
AU: Velasco, A A
EM: velasco@geo.utep.edu
AF: University of Texas at El Paso Department of Geological Sciences, 500 W. University Ave., El Paso, TX 79902 United States
AB: Many large-scale experiments conduct both controlled-source and passive deployments to investigate the lithospheric structure of a targeted region. Many of these studies utilize each data set independently, resulting in different images of the Earth depending on the data set investigated. In general, formal integration of these data sets, such as joint inversions, with other data has not been performed. The CD-ROM experiment, which included both 2-D controlled-source and passive recording along a profile extending from southern Wyoming to northern New Mexico serves as an excellent data set to develop a formal integration strategy between both controlled source and passive experiments. These data are ideal to develop this strategy because: 1) the analysis of refraction/wide-angle reflection data yields Vp structure, and sometimes Vs structure, of the crust and uppermost mantle; 2) analysis of the PmP phase (Moho reflection) yields estimates of the average Vp of the crust for the crust; and 3) receiver functions contain full-crustal reverberations and yield the Vp/Vs ratio, but do not constrain the absolute P and S velocity. Thus, a simple form of integration involves using the Vp/Vs ratio from receiver functions and the average Vp from refraction measurements, to solve for the average Vs of the crust. When refraction/ wide-angle reflection data and several receiver functions nearby are available, an integrated 2-D model can be derived. In receiver functions, the PS conversion gives the S-wave travel-time (ts) through the crust along the raypath traveled from the Moho to the surface. Since the receiver function crustal reverberation gives the Vp/Vs ratio, it is also possible to use the arrival time of the converted phase, PS, to solve for the travel time of the direct teleseismic P-wave through the crust along the ray path. Raytracing can yield the point where the teleseismic wave intersects the Moho. In this approach, the conversion point is essentially a pseudo-shotpoint, thus the converted arrival at the surface can be jointly modeled with refraction data using a 3-D inversion code. Employing the combined CD-ROM data sets, we will be investigating the joint inversion results of controlled source data and receiver functions.
DE: 7218 Lithosphere (1236)
SC: Seismology [S]
MN: Fall Meeting 2005