LASSIE is a cooperative experiment between industry and academia to image the deeper structure of the Los Angeles Basin with broadband seismology.

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Figure 1 Stations used in this study. The red and yellow dots are LASSIE stations, and the black circles are SCSN stations. The blue dots are LABPSE stations that are not used here. The green line denotes the location of the 2-D profile (A-A') we will show, and the distances are marked with blue crosses in 10 km intervals. The faults are shown in pink lines.

The LA Basin portion of the LASSIE data was used in the following two paper that determine the structure of the Los Angeles Basin

• Ma, Y, R. Clayton and D. Li, (2016a), Higher-mode ambient-noise Rayleigh waves in sedimentary basins, Geophys. J. Int, 206, 1634-1644. doi:10.1093/gji/ggw235     PDF     Supp
• Ma, Yiran, and R. Clayton, (2014), The Crust and Uppermost Mantle Structure of Southern Peru From Ambient Noise and Earthquake Surface Wave Analysis, Earth and Planetary Sci. Lett., 395, pp61-70. doi:10.1016/j.epsl.2014.03.013. PDF   PDF-supp

Preliminary results were presented in a poster at the 2014 SCEC Meeting. SCEC2014 Poster

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Results

Correlations

Figure 5 Example of the cross-correlations between N116 and all the yellow-dot stations in Fig.1. The y-axis shows the location of the stations along A-AÕ profile. The number of days for the correlations is noted to the right in blue. The profiles are filtered with Gaussian filter centered at 0.1 Hz and 0.5 Hz respectively. Both Love wave (in T-T component) and Rayleigh wave (in Z-Z component) are shown, and in 0.5 Hz profile, we also observe higher mode Rayleigh wave.

Results of Surface Wave Inversion

Figure 7 Phase velocity along A-A' profile. The y-axis is the period of the phase velocity.	Figure 8 A preliminary SV velocity structure inverted from the phase velocity in Fig. 7. For the differences between SV and SH, we only use Rayleigh wave for this result.

Results of Receiver Function Inversion

Figure 2 Receiver functions of two events recorded by all the yellow-dot stations in Fig. 1.	Figure 3 Depth-axis receiver functions with the time-depth conversion for PpPs phase.

Figure 4 CCP migration with PpPs phase. The white line delineates the inferred basement depth of the basin.

Phase Velocity Using SCSN Stations

Figure 6 Phase velocity map for the entire study region from cross-correlations among LASSIE and SCSN stations.