A Uniform Database of Teleseismic Shear- Wave Splitting Measurements for the Western and Central United States: December 2014 Update
نویسندگان
چکیده
We present a new version of a shear-wave splitting (SWS) database for the western and central United States (WCUS) using broadband seismic data recorded up to the end of 2014 to update a previous version that used data recorded prior to the end of 2012, when the USArray Transportable Array stations were still recording in the easternmost region of theWCUS. A total of 7452 pairs of additional measurements recorded by 1202 digital broadband seismic stations are obtained, and all the measurements in the previous database are rechecked. The resulting uniform SWS database contains a total of 23,448 pairs of well-defined SKS, SKKS, and PKS splitting parameters. Relative to the previous version of the database, the additional measurements notably improved the spatial and azimuthal coverages of the measurements, providing an improved dataset for constraining geodynamic models related to lithospheric deformation and asthenospheric flow, as well as for complex anisotropy recognition and characterization. Online Material: Tables of individual shear-wave splitting measurements, station-averaged measurements, and averaged splitting parameters.
منابع مشابه
NA-SWS-1.1: A uniform database of teleseismic shear wave splitting measurements for North America
[1] This version of shear wave splitting (SWS) database (DB) for North America (NA) contains 6224 pairs of splitting parameters (fast polarization directions and splitting times) measured using all the available data recorded by digital broadband seismic stations over the period of 1980–2007 and archived at the Incorporated Research Institutions for Seismology Data Management Center. The measur...
متن کاملOlivine fabric transitions and shear wave anisotropy in the Ryukyu subduction system
Recent shear wave splitting measurements from the fore-arc region of the Ryukyu subduction system show large magnitude (0.3–1.6 s) trenchparallel splitting in both local and teleseismic phases. The similarity of splitting parameters associated with shallow local-S and teleseismic phases suggests that the source of anisotropy is located in the fore-arc mantle. One explanation for this pattern of...
متن کاملNull Detection in Shear-Wave Splitting Measurements
Shear-wave splitting measurements are widely used to analyze orientations of anisotropy. We compare two different shear-wave splitting techniques, which are generally assumed to give similar results. Using a synthetic test, which covers the whole backazimuthal range, we find characteristic differences, however, in fast-axis and delay-time estimates near Null directions between the rotation corr...
متن کاملSplitLab: A shear-wave splitting environment in Matlab
We present a graphical user interface to facilitate the processing of teleseismic shear-wave splitting observations. In contrast to a fully automated technique, we present a manual, per-event approach that maintains user control during the sequence of processing. The SplitLab environment is intended to undertake the repetitive processing steps while enabling the user to focus on quality control...
متن کاملAnisotropy beneath California: shear wave splitting measurements using a dense broadband array
INTRODUCTION SUMMARY We have determined the shear wave splitting parameters for a dense network of broad-band stations in the western United States using high-quality SKS and SKKS waveforms, with par~ ticularly high spatial resolution in the southern California region covered by the TriNet seismic network. The alignment of most fast polarization directions can be explained by plate-tectonic, ex...
متن کامل