HR: 08:00h
AN: S31C-01 INVITED [Abstracts]
TI: Receiver Functions From Multiple-Taper Spectral Correlation: Backazimuthal Stacking, Single-Station
Migration, and Jackknife Uncertainty
AU: * Park, J
EM: jeffrey.park@yale.com
AF: Dept of Geology and Geophysics, PO Box 208109
Yale University, New Haven, CT 06520-8109
United States
AU: Levin, V
EM: vlevin@rci.rutgers.edu
AF: Dept of Geological Sciences, Rutgers University
610 Taylor Road
Wright Geological Laboratory, Piscataway, NJ 08854-8066
United States
AB:
The multiple-taper correlation (MTC) algorithm (Park & Levin, 2000)
for the estimation of teleseismic receiver functions (RFs)
has desirable statistical properties, but needs enhancement to exploit its potential. In particular, theory predicts that a
P-S conversion at an interface between anisotropic media will generate conjugate patterns of P-SV and P-SH converted waves
with the backazimuth of the incoming wave. Using a weighted back-azimuthal stack of MTC RFs, one can evaluate whether the
radial and transverse RF follow the anisotropic pattern, follow an independent pattern predicted for a dipping interface,
or exhibit random behavior that suggests scattering by 3-D structure.
Frequency
averaging implicit in spectral cross-correlation restricts the MTC RF estimates
to resolve Ps converted phases only at short delay times, appropriate to
the upper 100 km of Earth's lithosphere.
Ps conversions from deeper interfaces can be reconstructed by the MTC algorithm in two ways.
Event cross-correlation (ECC) computes a cross-correlation of single-taper spectrum
estimates for a cluster of events
rather than for a set of eigenspectrum estimates of a single P coda.
Moving-window migration (MWM) retains the multiple-taper approach, but cross-correlates
the P-polarized motion with SH or SV component motion that is time delayed to focus
on a Ps phase of interest.
An alternative error-propagation based on the jackknife offers uncertainty estimates
in the time domain.
DE: 3270 Time series analysis (1872, 4277, 4475)
DE: 3285 Wave propagation (0689, 2487, 4275, 4455, 6934)
DE: 7203 Body waves
DE: 7205 Continental crust (1219)
DE: 7220 Oceanic crust
SC: Seismology [S]
MN: Fall Meeting 2005