Data Services Products: EMC-PNW10-S S-velocity model of the Cascadia Subduction Zone

Summary

PNW10-S, Porritt et al. (2011) , PNW10-S combines the state of the art ambient noise tomography method with time tested analyst selection to ensure the highest quality data is used as input to the model inversion. Incorporating spatially and temporally long paths with this manual selection step allows recoverable structure from the surface to ~120km depth. This model focuses on the US Pacific Northwest to address a series of questions relating to variations in arc volcanism, seismicity, tremor activity, and the relation to subduction complex structure.

Description

Name PNW10-S
Title S-velocity model of the Cascadia Subduction Zone using Ambient Seismic Noise Tomography
Type 3-D Tomography Earth Model
Sub Type S velocity perturbation (%) and S velocity (km/s)
Year 2010
Short Description   S-velocity model of the Cascadia Subduction Zone using Ambient Seismic Noise Tomography. PNW10-S combines the state of the art ambient noise tomography method with time tested analyst selection to ensure the highest quality data is used as input to the model inversion. Incorporating spatially and temporally long paths with this manual selection step allows recoverable structure from the surface to ~120km depth. This model focuses on the US Pacific Northwest to address a series of questions relating to variations in arc volcanism, seismicity, tremor activity, and the relation to subduction complex structure.
Authors:  
Robert W. Porritt
Department of Earth and Planetary Science
University of California, Berkeley
California, USA
Richard M. Allen
Department of Earth and Planetary Science
University of California, Berkeley
California, USA
Devin C. Boyarko
Department of Geology
Miami University
Ohio, USA
Michael R. Brudzinski
Department of Geology
Miami University
Ohio, USA
Previous Model
Reference Model N/A
Model Download
original model files from the model download page
PNW10-S_percent.nc (metadata), is the netCDF binary for the above model.
Model Homepage seismo.berkeley.edu/~rallen/research/dna/pnw10
Depth Coverage 0 to 100 km
Areal Coverage Cross correlations span the entire US, with a handful of stations in Canada and Mexico. The inversion solves for relative structure from 33°N to 49.5°N latitude and 126°W to 110°W longitude, but we extract the well resolved section from 38.2°N to 49°N and 126°W to 119°W due to its data density.
 
Data Set Description [ Porritt et al. (2011) ] While our dataset focuses on two Flexible Array Experiment (FACES and Mendocino Broadband) more than 1200 stations where used from the USArray transportable array, regional seismic networks, and temporary seismic deployments. Phase velocities measured from inter-station paths with a Frequency-Time Analysis procedure to prepare period dependent maps.

a comparison of PNW10-S with characteristics of ETS

Figure , Porritt et al. (2011) , is a comparison of PNW10-S with characteristics of ETS. (a) Histogram showing variability in tremor occurrence along strike, Boyarko and Brudzinski (2010) . (b) Topography along profile. (c) Relative shear velocity structure along a profile where the slab is at 30 km depth (profile location shown in d). Vertical lines on profile at 43°N and 46.7°N indicate the tremor segmentation bounds of Brudzinski and Allen (2007) with the names and recurrence interval given. The horizontal line is the top of the ocean crust from Audet et al. (2010) . Also labeled are the slab sections corresponding to the Gorda, Southern Juan de Fuca (S. JdF) and Northern Juan de Fuca (N. JdF).

a comparison of PNW10-S with heat production observations

Figure, Porritt et al. (2011) , is a comparison of PNW10-S with heat production observations. (a) Cumulative heat production from the north to south along the arc, modified from Ingebritsen and Mariner (2010) . (b) Topography along profile with nearby volcanoes plotted as triangles. (c) Shear velocity structure along the profile that runs along the arc. Profile shown in the upper right (d). The black line around 40 km depth is the Moho. Major anomalies are labeled. Slow crust (SC) is the area of Basin and Range impingement. Slow mantles (SM1—4) are the interpreted ponded areas of melt. SM5 and SM6 are the plate segmentation boundaries separating the Gorda, Southern Juan de Fuca (S. JdF), and Northern Juan de Fuca (N. JdF).

Citation

  • Porritt, R.W., R.M. Allen, D.C. Boyarko , and M.R. Brudzinski. 2011. “Investigation of Cascadia segmentation with ambient noise tomography.” Earth and Planetary Science Letters, 309(1-2), 67-76, ISSN 0012-821X, DOI: 10.1016/j.epsl.2011.06.026.
  • 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 application, Seismological Research Letters, 83(6), 846:854. doi: 10.1785/0220 120032

References

  • Audet, P., M.G. Bostock, D.C. Boyarko, M.R. Brudzinski, and R.M. Allen. 2010. “Slabmorphology in the Cascadia fore arc and its relation to episodic tremor and slip.” J. Geophys. Res. 115, B00A16. doi:10.1029/2008JB006053.
  • Boyarko, D.C., and M.R. Brudzinski. 2010. Spatial and temporal patterns of nonvolcanic tremor along the southern Cascadia subduction zone.: J. Geophys. Res. 115:B00A22. doi:10.1029/2008JB006064.
  • Brudzinski, M., and R.M. Allen. 2007. “Segmentation in episodic tremor and slip all along Cascadia.” Geology 35 (10), 907—910. doi:10.1130/G23740A.1.
  • Ingebritsen, S.E. and R.H. Mariner. 2010. “Hydrothermal heat discharge in the Cascade Range, northwestern United States. J. Volcanol. Geotherm. Res. vol. 196 (Issues 3—4), 208—218. doi:10.1016/j.jvolgeores.2010.07.023 0377—273.

Credits

  • R.W. Porritt, R.M. Allen, D.C. Boyarko and M.R. Brudzinski

DOI

There is no DOI currently assigned for this product.

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