HR: 1330h
AN: S32B-0845    [PDF]
TI: Lithospheric Structure Beneath Asia From Surface-Waves and Receiver Functions
AU: * Ammon, C J
EM: cammon@geosc.psu.edu
AF: Penn State, Department of Geosciences 440 Deike Building, University Park, PA 16802 United States
AU: Randall, G E
EM: grandall@lanl.gov
AF: Los Alamos National Laboratory, MS D408 ES11 Los Alamos Seismic Research Center, Los Alamos, NM 87545 United States
AU: Sevilla, W I
EM: wsevilla@geosc.psu.edu
AF: Penn State, Department of Geosciences 440 Deike Building, University Park, PA 16802 United States
AB: We report on our investigations into the seismic structure of the lithosphere in central Asia using surface waves and receiver functions. We are relying on global and regional tomographic analyses for long-period surface-wave dispersion constraints on the structure, which we supplement with short-period observations measured directly from regional signals (when available). The combination of receiver functions and surface-wave dispersion information provides a complementary joint data set under certain conditions. Particularly troublesome are stations with strong, local near-surface heterogeneity, which masks the deeper structure in the receiver function. Stations with strong lateral variations in receiver response are also a challenge when the surface-wave information is restricted to a broad local average as a result of necessary smoothing of tomographic results. We present an overview of receiver function complexity across the region using receiver functions from many permanent and temporary stations. We have surveyed receiver functions from the INDEPTH III experiment and estimated Poisson's ratio variations across the south-central Plateau using the single-station stacking method of Zhu and Kanamori [2000]. Our results are consistent with those from earlier studies. We will illustrate the combined inversion of surface-waves and receiver functions using a variety of model constraints focusing on select stations including MAKZ, KURK, BRVK, CHTO, ULN, TLY, ABKT as well as stations from the NCDSN. We will present initial shear-velocity inversions obtained using dispersion estimates extracted from Eurasian tomographic models.
UR: http://eqseis.geosc.psu.edu/~cammon/AGUF03A
DE: 7200 SEISMOLOGY
DE: 7205 Continental crust (1242)
DE: 7218 Lithosphere and upper mantle
DE: 7219 Nuclear explosion seismology
DE: 7255 Surface waves and free oscillations
SC: Seismology [S]
MN: 2003 Fall Meeting