Receiver functions from seismic interferometry: a practical guide

Abstract

This paper reviews the concepts underlying the well-documented receiver functions (RFs) method, and places it in the conceptual framework of seismic interferometry. We first propose a simple and efficient approach for isolating the receiver-side seismic response (i.e. the record of reflections and conversions in the stratification beneath receivers): this method makes use of the P-wave coda recorded on the radial and vertical components of three-component stations, applies spectral whitening, which is followed by auto-and cross-correlation. The interferometric principle underpinning RFs analysis is shown theoretically and illustrated in practice using earthquake records and synthetic waveforms computed from simple structures. We point out to a major limitation, which is the contamination of the receiver-side response by propagation effects in the source-side structure. We then apply our approach to teleseismic earthquake data recorded in California. We show that the reconstructed vertical and horizontal seismic responses can be back-projected to illuminate the crustal and mantle structure. We build comparable ∼300-km-long seismic reflectivity profiles from pure P-wave reverberations and from the converted wavefield across the forearc and arc of the southern Cascadia subduction zone. Then, we show a case of processing data from narrow bandpass, short-period and single-component sensors, usually unsuitable for RFs analysis. Finally, through the same interferometric principle, we attempt to demonstrate a link between event-and noise-based seismic interferometry. We demonstrate that it is possible to extract approximate responses from the records of low-magnitude-down to 4.5-teleseismic earthquakes. We make a comparison of these estimates with the result from the autocorrelation of the continuous ambient noise seismic wavefield. While the amplitudes of the extracted receiver-side responses are mutually different, their phases are in a relative agreement. This development opens a way to the use of small magnitude teleseismic earthquakes to characterize the receiver-side structure.

Constraints on the shallow elastic and anelastic structure of Mars from InSight seismic data

“…Details of parameters used are given in Supplementary Discussion 4. One group applied spectral whitening and cross-correlation 57 . The parameters used in the processing and comparison of results with other methods are detailed in Supplementary Discussion 4.…”

On The Efficiency of P‐Wave Coda Autocorrelation in Recovering Crustal Structure: Examples From Dense Arrays in the Eastern United States

“…where p is the slowness of the impinging P-wave. We use the generalization of this expression to horizontally stratified media to compute a time-to-depth relationship and convert the time-domain auto-correlations into the depth-domain (Tauzin et al, 2019). This relationship is mode-dependent, and leads to destructive interference of signals that do not follow the move-out of P-wave reflections P P p. Single station auto-correlations are then linearly stacked in the depth domain.…”

“…The radial RFs are then depth-converted using a time-to-depth relationship for the direct Ps conversion mode Vertical (black) and radial (red) responses of the ground below the receiver for a simple, onelayer crust. In the vetical RF, the PPmp (PPp) and PPms (PPs) phases both exists but PPmp is much stronger (Tauzin et al, 2019). c) Topography, together with seismic sub-arrays used in this study and the seismicity (black circles) from the USGS catalog.…”

“…In supplementary Figure S11, we present an image of the crustal structure along the sub-array II based on the common reflection point stacking method (Tauzin et al, 2019), accounting for the geometry of illumination of the structure by the PPp mode.…”

“…P-wave reflections and P-to-S transmissions have a different sensitivity to velocity gradients (e.g. Bostock, 1999;Tauzin et al, 2019). We illustrate this by plotting the transmission and reflection coefficients T ps and Rpp as a function of the vertical extent h of a transitional layer adopting the contrasts in elastic properties for the Moho from Crust1.0 (Figure 10a).…”