Post on 03-Jan-2016
10 Sept 2006 SCEC/USGS Workshop: CA 3D Seismic Velocity Model
The Role of Ambient Noise Tomography in Developingthe California 3-D Seismic Velocity Model: Brief Thoughts
Venturabasin
LA basin
CentralValley
ImperialValley
Shapiro, Stehly, Campillo, & Ritzwoller, High resolutionsurface wave tomography from ambient seismic noise,Science, 307, 615, March 11, 2005.
Oct, 2004
•Past: •application to So. CA.•group speed maps•short periods (7 - 18 s).
•Present: •refinement of the method •application to new regions•extension to phase velo-
cIties & Love waves•larger scales, longer periods•smaller scales, shorter periods•inversion for 3D Vs.
•Near Future:•joint interpretation with other data.
SCEC/USGS Workshop: CA 3D Seismic Velocity Model
Applications to New Regions (W. US Using TA/ USArray) & Inversion for a Crustal Vs Model
16 sec, group velocity, 10/04-7/06
Map by Morgan Moschetti
SCEC/USGS Workshop: CA 3D Seismic Velocity Model
16 sec, group velocity, 10/04-7/06
group velocity
gro
up
ve
loci
ty
San Joaquin Valley
Applications to New Regions (W. US Using TA/ USArray) & Inversion for a Crustal Vs Model
SCEC/USGS Workshop: CA 3D Seismic Velocity Model
16 sec, group velocity, 10/04-7/06 Preliminary crustal thickness
Applications to New Regions (W. US Using TA/ USArray) & Inversion for a Crustal Vs Model
Inversion by Morgan Moschetti
SCEC/USGS Workshop: CA 3D Seismic Velocity Model
Extension to Phase Velocities at Longer Periods: High Resolution Mantle Constraints
25 sec
Phase velocity
Ambient noise
Yang & Moschetti
25 sec
Phase velocity
Teleseismic 2-plane wave method
Yang & Forsyth
SCEC/USGS Workshop: CA 3D Seismic Velocity Model
Closing Comment on the Use of Ambient NoiseTomographyThe Role of Ambient Noise Tomography in Developing the California 3-D Seismic Velocity Model: Closing Comments
•Complements other kinds of information: homogeneously distributed provides a means to integrate models from different regions way to extrapolate the model into new areas Vs in the crust & uppermost mantle
• More useful than traditional surface wave data: significantly higher resolution shorter period, provide constraints on the crust.
•Easily introduced into inversions in which other dataare interpreted jointly and with a priori constraints.