HR: 0800h
AN: S51A-0987    [Abstracts]
TI: Shear-Wave Velocity Structure of the New Madrid Seismic Zone From Rayleigh Wave Group Velocity Dispersion Using Regional and Local Earthquake Data
AU: * Jemberie, A L
EM: ajemberi@memphis.edu
AF: Center for Earthquake Research and Information, The University of Memphis, 3876 Central Ave., Memphis, TN 38152 United States
AU: Langston, C A
EM: clangstn@memphis.edu
AF: Center for Earthquake Research and Information, The University of Memphis, 3876 Central Ave., Memphis, TN 38152 United States
AB: Regional and local Rayeligh-wave group velocity dispersion data were used to extract shear-wave velocity structure of several propagation paths from earthquakes into the New Madrid Seismic Zone. The dispersion data are limited at high frequency by the mid-crustal depth of the earthquakes and at low frequency because of the relatively short propagation paths involved. Inferred dispersion curves also show irregularities possibly due to velocity heterogeneity along the path. The working passband occurs between frequencies of 0.05 and 0.5Hz. The dispersion data were inverted for shear-wave velocity structures. Our starting model for the inversion was a crustal model obtained from a seismic refraction experiment performed in the Eastern Tennessee Seismic zone. Preliminary results indicate a high shear-wave velocity layer at a depth of about 12-15km within the crust. The high velocity layer is seen to occur at a shallower depth compared to the result of the refraction data anlaysis of Catchings (1999) and the resolution is relatively poor for deeper parts of the crustal model.
DE: 7205 Continental crust (1219)
DE: 7255 Surface waves and free oscillations
DE: 7290 Computational seismology
SC: Seismology [S]
MN: Fall Meeting 2005