Number of products tagged with tomography (11).
EMC IRIS Earth Model Collaboration
A repository of Earth models with the aim of providing the research community with access to various Earth models, visualization tools for model preview, facilities to extract model data/metadata and access to the contributed processing software and scripts.
EMC-NA04 North American upper mantle surface wave tomography model
NA04, van der Lee and Frederiksen (2005) , is derived from inversion of the fundamental and higher mode Rayleigh waveforms using the Partitioned Waveform Inversion technique, Nolet (1990). The data set used includes waveforms from about 1400 regional seismograms recorded at North American digital broadband seismic stations (including the USArray Transportable Array waveforms). The NA04 3-D model is expressed as the velocity difference in m/s relative to the 1-D averaged Earth model MC35 .
EMC-NA07 North American upper mantle surface wave tomography model
NA07, Bedle and van der Lee (2009) , is based on the 3-D shear velocity model NA04 and the analysis of regional S and Rayleigh waveforms for earthquakes around North America from January 2000 through September 2006, including waveforms from the USArray Transportable Array stations. The NA07 3-D model is expressed as velocity difference in m/s relative to the 1-D averaged Earth model MC35.
EMC-NWUS11-P A 3-D P-wave tomography model for the northwestern United States
A 3-D P-wave tomography model for the northwestern United States, James et al. (2011) . The P-wave inversion for NWUS11-P is based on a total of 79,212 rays from 461 teleseismic events, with typical bandpass filter range of 0.5-1.5 Hz. The percent velocity perturbations reported by this model are insensitive to the starting 1-D reference model.
EMC-NWUS11-S A 3-D S-wave tomography model for the northwestern United States
A 3-D S-wave tomography model for the northwestern United States, James et al. (2011) . The S-wave inversion is based on a total of 88,689 rays from 379 teleseismic events, with typical bandpass filter ranges of 0.04-0.15 Hz. The percent velocity perturbations reported by this model are insensitive to the starting 1-D reference model.
EMC-SAW24B16 A global shear velocity structure of the mantle from body, surface and higher-mode waveforms
A 3-D shear velocity structure of mantle based on the inversion of body, surface, and higher mode waveforms, Megnin and Romanowicz (2000) . The model was derived from handpicked transverse component waveforms and is parameterized laterally in spherical harmonics up to degree 24 (Edmonds normalization) and radially in 16 unevenly spaced splines. The SAW24B16 model is expressed as the percent perturbation from PREM .
EMC-SAW642AN A global radially anisotropic mantle shear velocity model
SAW642AN, Panning and Romanowicz (2006) , is a radially anisotropic shear velocity model, parameterized in terms of isotropic S velocity (Voigt average) and the anisotropic parameter, xi (VSH2/VSV2). Model values are percent perturbation relative to the anisotropic reference model PREM500 .
EMC-SAW642ANb A global radially anisotropic mantle shear velocity model with improved crustal corrections
SAW642ANb, Panning, Lekic and Romanowicz (2010) , is a radially anisotropic shear velocity model of the mantel, parameterized in terms of isotropic S velocity (Voigt average) and the anisotropic parameter, xi (VSH2/VSV2). The waveform data used for this model consist of 3-component broad-band surface waveforms (short period corner of 80 seconds and cutoff of 60 seconds) as well as body waveforms (short period corner of 40 s and cutoff of 32 s). The spatial parameterization of the model is the same as SAW642AN , with 16 variably spaced cubic b-splines with depth, and level 4 spherical splines laterally. Model values are percent perturbation relative to the anisotropic reference model PREM500 .
EMC-TX2000 A global mantle shear-wave tomography model
TX2000 (also called Grand2000) refers here to the TXBW, Grand (2002) , model to distinguish it from the TXBW Grand, van der Hilst and Widiyantoro (1997) model. The model is derived from the shear body wave travel times and aims at providing a more uniform global coverage of the mantle and more information on the upper-mantle seismic structure by using analysis of multibounce shear waves, core-reflected waves and SKS and SKKS waves that travel through the core.
EMC-TX2011 A global shear-wave tomography model
TX2011 provides shear velocity perturbations with respect to the TX2011_ref reference model with the mean from the individual layers removed. The grid is not representative of the block size used in the inversion. The model assumes the crustal thickness is given by the Mooney, Laske and Masters crustal model, Mooney et al. (1998) , and thus velocity deviations in the upper most layer are with respect to a variable crustal thickness model.
EMC-wUS-SH-2010 P and S teleseismic body-wave tomography of the western United States
Teleseismic travel-time residuals from the EarthScope Transportable Array and more than 1700 additional stations are inverted for 3-D velocity perturbations. The inversion uses frequency-dependent 3-D sensitivity kernels to map travel-time residuals, measured in multiple frequency bands, into velocity structure.