1. Lithospheric Structure of the Gulf of California – Salton Trough Region, NARS-Baja Array Working Group: Robert Clayton, Caltech Don Forsyth, Brown Antonio Gonzalez-Fernandez, CICESE Craig Jones, Colorado Cecillio Rebollar, CICESE Jose Romo-Jones, CICESE

2. Science Questions: What is the rifting process and how does it vary from north to south in the Gulf What is the role of the remnant slab – where does it exist. Methods Map of the Moho from seismic and other geophysical methods. Map of the lithosphere/asthenosphere boundary. Velocity Variations from tomography studies. Flow directions from anisotropy Current strain from earthquakes Products 3D regional-scale velocity model Earthquake catalogue.

3. Lewis et al, 2001 Ichinose et al, 1996 Receiver Functions

4. Receiver Functions – Southern California Seismic Network Yan and Clayton, 2006

5. Crustal Thickness From Surface Waves Yang and Forsyth, 2005

7. NARS-Baja / RESBAN Array April, 2002 – April, 2007 http://www.data.scec.org/NARS-Baja/

8. Receiver Functions – Gulf of California Persaud, Perez-Campos and Clayton, 2005

9. NARS-Baja Station NE71 – Northern Baja Pennisula

10. NARS-Baja Stations NE78 & NE79 – Southern Baja Peninsula

11. NARS-Baja Station NE75 – Central Baja Peninsula

12. Cross-Peninsula Profile

13. Lopez-Pineda et al, 2005 I II III Along Peninsula Profiles

14. Romo, Gomez-Trevino, Esparza, Garcia-Abdesiem, and Flores-Luna, 2003 Electrical Profile

15. Regional 3D Velocity From Surface Waves and Receiver Functions DiLuccio, Clayton, Persaud, Perez-Campos, 2005

16. Rayliegh Wave Group Velocity Dispersion Curves for Four Events

19. DiLuccio, Clayton and Persaud, AGU, UGM, 2005 3D Regional-scale velocity model for the Gulf of California

20. DiLuccio, Clayton and Persaud, AGU, UGM, 2005

22. Gonzalez-Fernandez et al, 2005

23. The 2002 Gulf of California Seismic Experiment Lizarralde et al Column

24. Moho Top col 23.456 -117.234 123.0 SAMPLE1 lay 0.0 DEN 2700 VS 3.5 DVS 0.015 VP 5.0 DVP 0.015 TOP lay 5.0 DEN 2700 DDEN 10.0 VS 3.6 VP 6.0 DVP -0.02 lay 8.0 DEN 2800 VS 4.5 VP 7.0 MOHO Interface Names Column Description DEN, DDEN - density VS, DVS - shear velocity VP, DVP - P-wave velocity QS, DQS - S attenuation QP, DQP - P attenuation ???? - anisotropy Parameters

25. Moho Top (lat,lon,z)

26. SCSN Station JCS – Rapid Variations in Moho

27. Rayleigh waves Love waves 7071-R 7071-L 8081-R 8081-L Initial model Flow Direction From S-Wave Anisotropy – Rayleigh Vs Love Waves

28. Noise Correlation Microseism – 6 sec – station NE81 Infrasonic – 30-100 sec – NE82

29. Receiver Functions of Deeper Interfaces Perez-Campos, Persaud and Clayton, UGM, AGU 2004

30. Song and Helmberger, 2002