Data Services Products: EMC-SAAM23 South American Adjoint Model—iteration 23

Summary

SAAM23 is an elastic model for South America with transverse isotropy confined to the upper mantle, similar to its starting model, S362ANI.

Description

Name SAAM23
Title South American Adjoint Model—iteration 23
Type 3-D Tomography Earth Model
Sub Type Anisotropic (in the uppermost mantle)
Year 2022
Data Revision r0.0 (revision history)
 
Short Description   An elastic model for South America with transverse
isotropy confined to the upper mantle, similar to its starting model, S362ANI.
 
Authors: Caio Ciardelli, Department of Geophysics, Institute of Astronomy, Geophysics, and Atmospheric Sciences – USP, São Paulo, Brazil

Marcelo Assumpção, Department of Geophysics, Institute of Astronomy, Geophysics, and Atmospheric Sciences – USP, São Paulo, Brazil

Ebru Bozdağ, Department of Geophysics, Colorado School of Mines, Golden, USA

Suzan Van der Lee, Department of Earth and Planetary Sciences, Northwestern University, Evanston, USA

Author of parametrization: Caio Ciardelli, Department of Geophysics, Institute of Astronomy, Geophysics, and Atmospheric Sciences – USP, São Paulo, Brazil
 
Starting Model S362ANI
 
Reference Model STW105
 
Model Homepage https://github.com/caiociardelli/saam23
Model Download SAAM23.r0.0-n4.nc (see metadata) in the Polar Stereographic Projection and in netCDF 4 Classic format.
 
Depth Coverage Whole Mantle (10 to 1,500 km)
 
Area South America (latitudes: -60°/16°, longitudes: -88°/-10°)
 
Data Set Description 112 earthquakes in the moment-magnitude range 5.8 ≤ Mw ≤ 7.0 and 1,311seismic stations, totalizing 20,884 unique ray paths. The events were chosen to provide broad geographical coverage, including shallow (depth ≤ 50 km), intermediate (50 km > depth > 300 km), and deep (depth ≥ 300 km) events. Because we used relatively long-period data (>17 s) and events with magnitudes less than 7, we chose a Centroid Moment-Tensor (CMT) pointsource earthquake representation. Initial CMT solutions were selected from the global CMT catalogue .
 
 

anomalies at 110 km depth
Figure modified from Ciardelli et al. 2022: (a) βv anomalies at 110 km depth for the starting model (S362ANI). The white contours show the cratons and the magenta line shows the top contour of the Nazca Slab according to Slab2 (Hayes, 2018). (b) Same as (a), but now showing the result after 23 iterations (SAAM23). The regions in which the coverage density was below 10% of the maximum were masked to light gray. All % anomalies refer to the average velocity of the SAAM23 model shown in Figure S14 in Supporting Information S1(Ciardelli et al., 2022).

Citations and DOIs

To cite the original work behind this Earth model:

  • Ciardelli, C., Assumpção, M., Bozdağ, E., & Van der Lee, S. (2022). Adjoint Waveform
    Tomography of South America. Journal of Geophysical Research: Solid Earth, 127(2),
    e2021JB022575, https://doi.org/10.1029/2021JB022575

To cite the model parametrization effort:

*Ciardelli, C., Bozdağ, E., Peter, D., & Van der Lee, S. (2022). SphGLLTools: A toolbox for
visualization of large seismic model files based on 3D spectral-element meshes.
Computers & Geosciences, 159, 105007, https://doi.org/10.1016/j.cageo.2021.105007

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: https://doi.org/10.17611/dp/emc.2022.saam23.1

References

  • G. P. Hayes, G. L. Moore, D. E. Portner, M. Hearne, H. Flamme, M. Furtney, G. M. Smoczyk, Slab2, a comprehensive subduction zone geometry model. Science 362, 58–61 (2018).

Credits

  • r0.0 model provided by Caio Ciardelli.

Revision History

revision r0.0: uploaded May 20, 2022.

Timeline

2022-05-23
online

Categories

07:08:59 v.d6084d45