1 / 40

Introduction to Receiver Functions

Introduction to Receiver Functions. Definition of a Receiver Function Slant Stacking Modeling of Receiver Functions S-wave Receiver Functions. LQ. LR. Body Waves P and S waves Particle Motion. Body Waves: Polarization. P, SV, and SH :. Seismic Body Waves. Receiver Functions.

beyla
Télécharger la présentation

Introduction to Receiver Functions

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Introduction to Receiver Functions • Definition of a Receiver Function • Slant Stacking • Modeling of Receiver Functions • S-wave Receiver Functions

  2. LQ LR

  3. Body WavesP and S waves Particle Motion

  4. Body Waves: Polarization P, SV, and SH :

  5. Seismic Body Waves

  6. Receiver Functions

  7. Fundamental Assumptions • Plane Wave Approximation • The PS is primarily recorded on the radial (the vertical component is negligible) • These assumptions lead to the result that the receiver function *only* includes P-to-S converted energy

  8. PS-wave P-wave What factors influence r0/z0?

  9. Isolating Mode Conversions

  10. Methods of Deconvoltuion • Spectral Division: water level technique (Burdick and Langston, 1978) • Stacked Time Domain Deconvolution (Baker et al., 1996) • Individual Iterative Time Domain Deconvolution (Liggoria and Ammon, 1999)

  11. WATER-LEVEL DECONVOLUTION • > water-level deconvolution introduced by Clayton & Wiggins • > for small c approaches deconvolution, large c approaches scaled cross-correlation • > similar to damped least squares solution

  12. Time Domain CONVOLUTIONAL MODEL • observed displacement seismogram • effective source (includes source-side scattering) • Green’s function (receiver side response to an impulsive plane wave with horizontal slowness )

  13. PS-phase Move-out:

  14. Crustal Multiples:

  15. P S PPP PPS PSS P PS SCATTERING GEOMETRY • > consider plane P wave incident from below • > receiver side scattering includes forward and back scattering, P and S • > legs ending in P and S isolated through modal decomposition

  16. Slant Stacking

  17. Synthetic Receiver Functions:

  18. LEAST-SQUARES INVERSION • > receiver function inversion cast in standard inverse theory framework • > less expensive than MC/DS methods and makes less stringent demands on data than inverse scattering methods • > data insufficiency compensated for by regularization (e.g. damping) • > like MC/DS methods LS involves model matching so there is no formal requirement that data are delivered as Green’s functions (e.g. receiver function is adequate); only a forward modelling engine is strictly required

  19. Receiver Functions

  20. Receiver Function Footprints 40 km Interface 15 km Interface

  21. Migrating Receiver Functions

  22. ASCENT P-wave Receiver Functions

  23. S wave Receiver Functions

  24. S Receiver Functions From Farra and Vinnik, 2000

  25. Comparisons with P Receiver Functions

  26. Migrated S-wave Receiver Functions Angus et al., 2005

  27. Han et al., 2010: T43A-2158

  28. For Next Time:Mike Pasyanos:Surface Wave Dispersion

  29. SIMULTANEOUS DECONVOLUTION • > when large numbers of seismograms representing a single receiver/Green’s function are available, perform simultaneous, least-squares deconvolution • > advantageous due to fact that smaller sum of spectra in denominator reduce likelihood of spectral zeros allowing for smaller values of water level parameter to be used • > Gurrola et al, 1995, GJI, 120, 537-543

  30. Background: Geodynamic models of Tibetan plateau [Yin and Harrison, 2000] [Tapponnier et al., 2001] [Fu et al., 2008] [Willett and Beaumont, 1994] [Kind et al., 2002] Unknown deep structure Mainly north-south profiles

  31. [Zhao et al., 2010] [Kumar et al., 2006]

  32. Migrated S-wave Receiver Functions

More Related