Taka'aki Taira
Post-Doctoral Fellow
Ph.D., Hokkaido University, Japan, 2004

Department of Geology and Geophysics
University of Utah
135 South 1460 East, Room 706
Salt Lake City, UT 84112

Phone: (801) 581-7856
Fax: (801) 581-7065 (departmental office)
Email: taira@seis.utah.edu
Research group's web page:
Seismology and Active Tectonics Research Group

Research Interests
Transient stress changes at seismogenic depth, subsurface hydrothermal fluid migration, source mechanism of fluid-induced earthquakes, seismic imaging of crustal structure, developing seismic array methodologies, seismic wave propagation, and modeling of conduit flow dynamics.

My research focus is on the subsurface structure of the Earth. In particular, I am interested in transient stress changes at seismogenic depth before, during, and after large earthquakes. I develop a methodology for detecting time-evolution of subsurface stress field by using scattered wavefields from repeating-earthquake clusters. I am also interested in subsurface hydrothermal fluid migration to monitor volcanic activity, by applying the developed methodology and through source properties of earthquakes.

My current research has focused primarily on 1) detecting repeating earthquakes, volcanic tremors, fluid-induced earthquakes in the Yellowstone area and 2) estimating their source properties by systematic analyses of seismic, GPS, and strain data.

Publications

• Taira, T., I. S. Sacks, A. T. Linde, and D. Hidayat, Pressure oscillation in magma chamber due to replenishment during volcanic eruptions, in preparation.

• Taira, T., P. G. Silver, F. Niu, and R. M. Nadeau, Seismic imaging of scatterers at seismogenic depth, San Andreas Fault, Parkfield, CA., in preparation.

• Taira, T., K. Yomogida, Y. Kuwahara, K. Imanishi, and H. Ito, Characteristics of high-frequency seismic scatterers as inferred from a new parameterization, in preparation.

9. Taira, T., P. G. Silver, F. Niu, and R. M. Nadeau (2008), Detecting seismogenic stress evolution and constraining fault zone rheology in the San Andreas Fault following the 2004 Parkfield earthquake, J. Geophys. Res., 113, B03303, doi:10.1029/2007JB005151. (Download pdf reprint)

8. Taira, T., K. Yomogida, Y. Kuwahara, K. Imanishi, and H. Ito (2007), Imaging of crustal heterogeneous structures using a slowness-weighted back-projection with effects of scattering modes II: Application to the Nagamachi-Rifu fault, Japan, area, J. Geophys. Res., 112, B06312, doi:10.1029/2006JB004382. (Download pdf reprint)

7. Taira, T., and K. Yomogida (2007), Imaging of crustal heterogeneous structures using a slowness-weighted back-projection with effects of scattering modes I: Theory, J. Geophys. Res., 112, B06311, doi:10.1029/2006JB004381. (Download pdf reprint)

6. Onizawa, S., H. Oshima, H. Aoyama, H. Y. Mori, T. Maekawa, A. Suzuki, T. Tsutsui, N. Matsuwo, J. Oikawa, T. Ohminato, K. Yamamoto, T. Mori, T. Taira, H. Miyamachi, and H. Okada (2007), P-wave velocity structure of Usu volcano: Implication of structural controls on magma movements and eruption locations, J. Volcano. Geotherm. Res., 160, 175-194, doi:10.1016/j.jvolgeores.2006.10.005. (Link to article)

5. Iwasaki, T., K. Adachi, T. Moriya, H. Miyamachi, T. Matsushima, K. Miyashita, T. Takeda, T. Taira, T. Yamada, and K. Ohtake (2004), Upper and middle crustal deformation of an arc–arc collision across Hokkaido, Japan, inferred from seismic refraction/wide-angle reflection experiments, Tectonophysics, 388, 59-73, doi:10.1016/j.tecto.2004.03.025. (Link to article)

4. Taira, T., and K. Yomogida (2004), Imaging of three-dimensional small-scale heterogeneities in the Hidaka, Japan region: Coda spectral analysis, Geophys. J. Int., 158(3), 998-1008, doi:10.1111/j.1365-246X.2004.02333.x. (Download pdf reprint)

3. Taira, T., and K. Yomogida (2003), Characteristics of small-scale heterogeneities in the Hidaka, Japan, region estimated by coda envelope level, Bull. Seis. Soc. Am., 93, 1531-1541. (Download pdf reprint)

2. Taira, T., T. Moriya, H. Miyamachi, N. Wada, S. Hirano, K. Otsuka, W. Matsubara, and Y. Maruyama (2002), Seismic refraction experiment in the northeastern part of Hokkaido, Japan (in Japanese with English abstract), Bull. Earthq. Res. Inst. Univ. Tokyo, 77, 225-230.

1. Taira, T., and K. Tsumura (2001), The identification and removal of artificial events from the JMA and Tohoku University earthquake catalogs (in Japanese), Journal of the Seismological Society of Japan, 53, 255-258.