HR: 1340h
AN: S43B-1305 [Abstracts]
TI: Receiver Function Multiple Suppression and Separation
AU: * Bostock, M G
EM: bostock@eos.ubc.ca
AF: Department of Earth and Ocean Sciences, The University of British Columbia, 6339 Stores
Rd, Vancouver, BC V6T 1Z4, Canada
AB:
Interrogation of the continental lithospheric mantle using
P-receiver functions is rendered difficult by the
contaminating influence of free-surface multiples originating
from the crust-mantle boundary. Recently, the use of S-receiver functions
has been advanced as a better means of achieving this objective due to the fact
that conversions and multiples arrive in distinct temporal
windows. However, S-receiver functions suffer from a number of other
disadvantages, notably, high levels of signal generated noise and
significantly smaller data sets for a given recording period. A means of
suppressing/separating free-surface multiples within P-receiver functions
could provide a valuable tool for corroborating S-recever function
results and might allow more general characterization of the continental
mantle using data from portable experiments.
We examine the use of the single-scattering Kirchhoff approximation for
1-D media to this end. By assuming a correlation between material
properties (through e.g. constant Poisson's ratio, Birch's law), we may
construct operators that accomplish approximate separation of
direct conversions and free-surface multiples for a single receiver function.
We demonstrate the application of this approach through a series of numerical
examples and assess its efficacy when the underlying assumptions
(i.e. known material property correlations, 1-D structure) are not fully
honoured. Applications of the method to data from permanent stations of the
Global Seismic Network and Canadian National Seismograph Network will
be presented.
DE: 7203 Body waves
DE: 7205 Continental crust (1219)
DE: 7218 Lithosphere (1236)
DE: 7260 Theory
SC: Seismology [S]
MN: 2007 Fall Meeting