Data Services Products: EMC-WUS-CAMH-2015 3D shear-wave velocity model of the western United States

Summary

WUS-CAMH-2015 (Chai, Ammon, Maceira, and Herrmann, 2015) is a shear velocity model that combines spatially interpolated/smoothed receiver functions, surface-wave dispersion and gravity observations through a 3D simultaneous inversion to image the subsurface S-wave velocity structure of the western U.S. region.

Description

Name WUS-CAMH-2015
Title 3D shear-wave velocity model of the western United States
Type 3-D Tomography Earth Model
Sub Type Shear-wave velocity (km/s)
Year 2015
Short Description   The WUS-CAMH-2015 shear velocity model combines spatially interpolated/smoothed receiver functions, surface-wave dispersion and gravity observations through a 3D simultaneous inversion to image the subsurface S-wave velocity structure of the western U.S. region. Data include 3608 interpolated P-wave receiver functions, 900 Rayleigh-wave group velocity dispersion curves, and wavenumber filtered Bouguer gravity observations. Constrained by simplified receiver functions and multiple geophysical observations, the velocity model is a reliable starting point for more detailed seismic investigations. Supplements to the original manuscript (available from AGU) include the original-formatted model along with Python and Fortran tools for extracting pieces of the model.
Authors:  
Chengping Chai
Department of Geosciences
Pennsylvania State University
University Park, PA, 16802, USA
Charles J. Ammon
Department of Geosciences
Pennsylvania State University
University Park, PA, 16802, USA
Monica Maceira
Los Alamos National Laboratory
Los Alamos, NM, 87545, USA
Robert B. Herrmann
Department of Earth and Atmospheric Sciences
Saint Louis University
St. Louis, MO, 63108, USA
Previous Model None
Reference Model None
Model Download
The above model expressed as shear velocity in km/s. Density (g/cm3) and P-wave velocity (in km/s) are also provided, which are inferred based on the imperial relationship between density and shear wave velocity (Maceira and Ammon, 2009) and Vp/Vs ratios from Crust 1.0 (Laske et al., 2013):
WUS-CAMH-2015.nc (see metadata ), is the netCDF file for the model
Depth Coverage 0 to 2048 km
Area Western U.S. region (latitude: 25°/55°, longitude: -127°/-97°)
 
Data Set Description [Chai et al. (2015)] The dataset includes spatially interpolated/smoothed P-wave receiver functions from ~1000 stations, Rayleigh-wave group velocities (short periods from Herrmann et al., 2013 and long periods from Ekström, 2011), and wavenumber filtered Bouguer gravity observations (Balmino et al., 2012).
 
Supplemental Information The supplemental information page for this model contains images comparing single-station averaged receiver functions with spatially interpolated/smoothed receiver functions, clustering analysis results of the WUS-CAMH-2015 3D shear wave velocity model, synthetic tests of receiver function interpolation, applications of receiver function interpolation for smaller seismic arrays, and an animation of different time slices of receiver functions.
 

Shear velocity WUS-CAMH-2015
Figure, Chai et al. (2015), representative shear velocity slices through the 3D model. Dark lines show the physiographic boundaries. The anomalies show a combination of variations in sedimentary basin and crustal thickness with lateral variations in shear-wave speed within the crust and mantle. A complete set of model depth slices and all data fit plots are available in the supplement of Chai et al. (2015).

Citations and DOIs

To cite the original work behind this Earth model:

  • Chai, C., C. J. Ammon, M. Maceira, and R. B. Herrmann (2015), Inverting interpolated receiver functions with surface wave dispersion and gravity: Application to the western U.S. and adjacent Canada and Mexico, Geophysical Research Letters, 42(11), 4359-4366, https://doi.org/10.1002/2015GL063733.

To cite IRIS DMC Data Products effort:

  • Trabant, C., A. R. Hutko, M. Bahavar, R. Karstens, T. Ahern, and R. Aster (2012), Data Products at the IRIS DMC: Stepping Stones for Research and Other Applications, Seismological Research Letters, 83(5), 846–854, https://doi.org/10.1785/0220120032.

DOI for this EMC webpage:

References:

Balmino, G., N. Vales, S. Bonvalot, and A. Briais (2012), Spherical harmonic modelling to ultra-high degree of Bouguer and isostatic anomalies, J. Geod., 86(7), 499–520, https://doi.org/10.1007/s00190-011-0533-4.

Ekström, G. (2011), A global model of Love and Rayleigh surface wave dispersion and anisotropy, 25–250 s, Geophys. J. Int., 187(3), 1668–1686, https://doi.org/10.1111/j.1365-246X.2011.05225.x.

Herrmann, R. B., C. J. Ammon, and H. Benz (2013), Group velocity dispersion for North America. [Available at http://www.eas.slu.edu/eqc/eqc_research/NATOMO.]

Laske, G., G. Masters, Z. Ma, and M. Pasyanos (2013), Update on CRUST1.0—A 1-degree global model of Earth’s crust, Abstracts EGU2013-2658 presented at 2013 EGU General Assembly Conference, Vienna, Austria, 7–12 April.

Maceira, M., and C. J. Ammon (2009), Joint inversion of surface wave velocity and gravity observations and its application to central Asian basins shear velocity structure, J. Geophys. Res., 114, B02314, https://doi.org/10.1029/2007JB005157.

Credits

Model provided Chengping Chai

Timeline

2016-06-27
online

Contact

Categories

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