Summary
Simmons, Myers, Johannesson & Matzel (2012) , is a global-scale model of the crust and mantle P-wave velocity with regional-scale details. The model is parameterized using a spherical tessellation with node spacing of ~1 degree in the upper mantle and ~2 degrees in the lower mantle.
Quicklinks
Description
| Name | LLNL-G3Dv3 |
| Title | A global P wave tomography model based on regional and teleseismic travel times |
| Type | 3-D Tomography Earth Model |
| Sub Type | P velocity |
| Year | 2012 |
| Short Description | LLNL-G3Dv3 is a global-scale model of the crust and mantle P-wave velocity with regional-scale details. The model is parameterized using a spherical tessellation with node spacing of ~1 degree in the upper mantle and ~2 degrees in the lower mantle. Although a spherical tessellation was used to define the lateral positioning of nodes, the model itself is aspherical with Earth’s ellipticity, mantle stretching and undulating discontinuities in the crust and upper mantle built-in. In total, the model consists of 57 layers from the surface to the core and ~1.6 million nodes. 3-D ray tracing and a multi-scale imaging technique (PMTI, Simmons et al., 2011 ) were employed to create the image. |
| Usage Notes | Currently this model is not available under netCDF format. |
| Authors: | |
| Nathan A. Simmons | |
| Atmospheric, Earth and Energy Division | |
| Lawrence Livermore National Laboratory | |
| Livermore, California, USA | |
| Stephen C. Myers | |
| Atmospheric, Earth and Energy Division | |
| Lawrence Livermore National Laboratory | |
| Livermore, California USA | |
| Gardar Johannesson | |
| Systems and Decision Sciences | |
| Lawrence Livermore National Laboratory | |
| Livermore, California USA | |
| Eric Matzel | |
| Atmospheric, Earth and Energy Division | |
| Lawrence Livermore National Laboratory | |
| Livermore, California USA | |
| Previous Model | |
| Reference Model | |
| Model Download | |
| LLNL_G3Dv3_Vp_Model.zip (~34 MB) — Complete model package containing: | |
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| Velocity values are expressed as absolute velocity and percentage variations relative to the layer average. | |
| Model Homepage | |
| Depth Coverage | Surface to core-mantle boundary (CMB) |
| Area | Global (-90°/90°, -180°/180°) |
| Data Set Description | The model was developed using over 2.8 million groomed and reprocessed P and Pn travel times with events located with the Bayesloc global multiple event location technique (Myers et al. 2007, 2009, 2011 ). Original data sources include the EHB bulletin (Engdahl et al., 1998 ) provided by the International Seismological Centre (ISC), the National Earthquake Information Center (NEIC) bulletin, and a variety of regional bulletins. Additional data are derived from seismic deployments for Peaceful Nuclear Explosions (PNE’ss), large refraction surveys, the USARRAY Transportable Array (TA) and temporary PASSCAL deployments around the world (IRIS ). |
| Supplemental Information | The supplemental information page for this model that also includes the LLNL-Earth3D code for extracting model parameters, tracing rays, and computing travel times. |
Citations and DOIs
To cite the original work behind this Earth model:
- Simmons, N.A., S.C. Myers, G. Johannesson, and E. Matzel. 2012. “LLNL-G3Dv3: Global P wave tomography model for improved regional and teleseismic travel time prediction.” J. Geophys. Res. 117:B10302, https://doi.org/10.1029/2012JB009525.
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
- Engdahl, E.R., R. van der Hilst, and R. Buland. 1998. “Global teleseismic earthquake relocation with improved travel times and procedures for depth determination.” Bull. Seismol. Soc. Am., 88:722-743.
- Myers, S.C., G. Johannesson, and W. Hanley. 2007. “A Bayesian hierarchical method for multiple-event seismic location.” Geophys. J. Int., 171:1049-1063, https://doi.org/10.1111/j.1365-246X.2007.03555.x.
Credits
- N.A. Simmons, S.C. Myers, G. Johannesson, and E. Matzel
Timeline
- 2014-07-07
- Online
