Summary
A degree 8 3-D Q model of the upper mantle by Gung and Romanowicz (2004) , derived from three component surface waveform data in the period range of 60-400 seconds. Model is parameterized in spherical harmonics for lateral variations and cubic b-splines for depth dependence up to maximum spherical harmonics degree 16 horizontally for the SV-velocity model and 8 for the Q model with the use of 16 B-splines vertically (throughout the mantle). The velocity model is expressed as perturbations from the spherically symmetric model PREM .
Quicklinks
Description
| Name | QRLW8 |
| Title | A global upper mantle shear wave attenuation model |
| Type | 3-D Q Model |
| Sub Type | Shear wave attenuation |
| Year | 2002 |
| Short Description | A degree 8 three-dimensional Q model of the upper mantle, derived from three component surface waveform data in the period range 60-400 sec. |
| Authors: | |
| Yuancheng Gung | |
| Berkeley Seismological Laboratory | |
| University of California, Berkeley | |
| Barbara Romanowicz | |
| Berkeley Seismological Laboratory | |
| University of California, Berkeley | |
| Previous Model | |
| Reference Model | |
| Model Download | QRLW8_model.tar (~65 kB), source code and executable for QA1grid to output model value for a given depth, latitude and longitude. The unit of the output value is d(1/2Q)x1000 with respect to QL6c.1D model that is also included in the package. |
| Model Homepage | |
| Depth Coverage | Upper Mantle (80 to 670 km) |
| Area | Global ( -90°/90°, 0°/360°) |
| Data Set Description | Three-component surface waveform data in the period range 60-400s |
Citations and DOIs
To cite the original work behind this Earth model:
- Gung, Y. and B. Romanowicz. 2004. “Q tomography of the upper mantle using three-component long-period waveforms.” Geophysical Journal International, 157:813-830. https://doi.org/10.1111/j.1365-246X.2004.02265.x.
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
- Richards, M.A., B.H. Hager, and N.H. Sleep. 1988. “Dynamically supported geoid highs over hotspots: Observation and theory.” J. Geophys. Res. 93:7690-7780.
Credits
- Y. Gung and B. Romanowicz
Timeline
- 2010-12-09
- Online
