Data Services Products: EMC-SNEP_Ptomo P-wave teleseismic tomography of the Sierra Nevada and surroundings

Summary

P-wave velocity models of the Sierra Nevada and surrounding regions using teleseismic P-wave travel times recorded by the Sierra Nevada Earthscope Project (SNEP), Earthscope TA stations, and permanent stations. Multiple starting models are used to circumscribe the uncertainties associated with crustal structure only poorly constrained by the tomography alone.

Description

Name SNEP_Ptomo
Title P-wave teleseismic tomography of the Sierra Nevada and surroundings
Type 3-D tomographic earth model
Sub Type P-wave velocity perturbation
Year 2014
Data Revision r0.0 (revision history)
 
Short Description   P-wave velocity models of the Sierra Nevada and surrounding regions using teleseismic P-wave travel times recorded by the Sierra Nevada Earthscope Project (SNEP), Earthscope TA stations, and permanent stations. Multiple starting models are used to circumscribe the uncertainties associated with crustal structure only poorly constrained by the tomography alone.
 
Authors: Craig H. Jones, Department of Geological Sciences and Cooperative Institute for Research in Environmental Sciences, University of Colorado at Boulder, Colorado 80309-0216, USA

Heidi Reeg, Department of Geological Sciences and Cooperative Institute for Research in Environmental Sciences, University of Colorado at Boulder, Colorado 80309-0216, USA

George Zandt, Department of Geosciences, University of Arizona, Gould-Simpson Building #77, 1040 E. 4th Street, Tucson, Arizona 85721, USA

Hersh Gilbert ,Department of Earth and Atmospheric Sciences, Purdue University, 550 Stadium Mall Drive, West Lafayette, Indiana 47907, USA

Thomas J. Owens, Department of Earth and Ocean Sciences, University of South Carolina, 701 Sumter Street, EWS 617, Columbia, South Carolina 29208, USA

Josh Stachnik, Department of Earth and Environmental Sciences, Lehigh University, 1 West Packer Avenue, Bethlehem, Pennsylvania 18015-3001, USA
 
Previous Model None
 
Reference Models For Vp_1D, IASPEI was the starting model (Kennett and Engdahl, 1991 ). For Vp_1D_GV, IASPEI was also used but arrival times at stations in the Great Valley were corrected for the sedimentary cover. Other starting models were based on shear-wave models that were converted to P-wave velocity using a Vs to Vp regression of Brocher. For all Vp_Mosch variants, the IASPEI model was replaced by the top 120 km of the S-wave model of Moschetti et al. (JGR, 2010) converted to P-wave values. This was based on ambient noise tomography and ballistic surface waves. For Vp_Mosch the inversion was unconstrained from the start. For Vp_MoschFix the top 40 km were held fixed for 14 iterations. For Vp_MoschFixFree the inversion was freed for 10 additional iterations. For all Vp_Hersh variants the S-wave model of Gilbert et al. (Geosphere, 2012) replaced the top 120 km of the IASPEI model. The Vp_Hersh, Vp_HershFix, Vp_HershFixFree models had the same procedure as the equivalent Vp_Mosch models. Two model embedded an otherwise unpublished S-wave wave ambient noise model from Josh Stashnik local to the Sierra within the broader Moschetti et al. (JGR, 2010) model. One extended only to 40 km depth, the other to 120 km depth.
 
Model Download SNEP-PTomo.r0.0.nc (see metadata) in netCDF 3 Classic format.
Model Homepage None
 
Depth Coverage 0-430 km
 
Area The inversion extended from 30.973° N to 46.246°N and 127.74°W to 111.864°W. The supplied model is limited to 33.893°N to 43.102°N and 124.176°W to 115.752°W where resolution was usually adequate. The best resolution is in the Sierra where the SNEP stations were present.
 
Data Set Description P-wave travel times picked with dbxcor software from the SNEP FlexArray dataset (doi:10.7914/SN/XE_2005) and coeval Transportable Array and permanent stations as listed in Jones et al. (2014). These are supplemented with picks from a 1988 experiment in the southern Sierra (Jones et al., JGR, 1994 ) and the 1997 Sierra Paradox Experiment (SPE) deployment (Jones and Phinney, JGR, 1998; data at IRIS as doi:10.7914/SN/XJ_1997). A total of 340 station locations were used and 29,186 P-wave arrival times.
 
 

Map views of P wave speed variations at two depths
Map views of P wave speed variations at two depths (40 and 70 km) illustrating the impact of differing starting models: a one-dimensional (IASPEI) starting more on the left and a 3-D model based on the upper 55 km of a surface wave model of Moschetti et al. (2010) on the right.

Citations and DOIs

To cite the original work behind this Earth model:

  • Jones, C. H., Reeg, H., G. Zandt, H. Gilbert, T. J. Owens, J. Stachnik, P-wave tomography of potential convective downwellings and their source regions, Sierra Nevada, California, Geosphere, 10 (3), 505-533, https://doi.org/10.1130/GES00961.1, 2014.

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.2021.snepptomo.1

References

  • Brocher, T.A., 2005, Empirical relations between elastic wavespeeds and density in the Earth’s crust: Bulletin of the Seismological Society of America, v. 95, no. 6, p. 2081–2092, https://doi.org/10.1785/0120050077.

  • Gilbert, H., Yang, Y., Forsyth, D.W., Jones, C.H., Owens, T., Zandt, G., and Stachnik, J., 2012, Imaging lithospheric foundering in the structure of the Sierra Nevada: Geosphere, v. 8, no. 6, p. 1310–1330, doi:10.1130 /GES00790.1.

  • Jones, C.H., and Phinney, R.A., 1998, Seismic structure of the lithosphere from teleseismic converted arrivals observed at small arrays in the southern Sierra Nevada and vicinity, California: Journal of Geophysical Research, v. 103, no. B5, p. 10,065–10,090, https://doi.org/10.1029/97JB03540.

  • Jones, C.H., Kanamori, H., and Roecker, S.W., 1994, Miss- ing roots and mantle “drips”: Regional Pn and teleseismic arrival times in the southern Sierra Nevada and vicinity, California: Journal of Geophysical Research, v. 99, p. 4567–4601, https://doi.org/10.1029/93JB01232.

  • Kennett, B.L.N., and Engdahl, E.R., 1991, Traveltimes for global earthquake location and phase identification: Geophysical Journal International, v. 105, no. 2, p. 429–465, https://doi.org/10.1111/j.1365-246X.1991.tb06724.x.

  • Moschetti, M.P., Ritzwoller, M.H., Lin, F.-C., and Yang, Y., 2010, Crustal shear wave velocity structure of the western United States inferred from ambient seismic noise and earthquake data: Journal of Geophysical Research, v. 115, no. 10, B10306, https://doi.org/10.1029/2010JB007448.

Credits

  • r0.0 model provided by Craig Jones.

Revision History

revision r0.0: uploaded June 1, 2021.

Timeline

2021-06-03
online

Categories

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