Victor's Homepage

Victor C. Tsai

Victor Tsai

email: tsai [at] caltech . edu
address:   California Institute of Technology
                1200 E. California Blvd., MS 252-21
                   Pasadena, CA 91125
phone: office: 626-395-6993

Where Am I Now?
I have moved to Brown University, where I am now an Associate Professor in the Department of Earth, Environmental and Planetary Sciences. Please see my updated webpage here.

Professional Appointments
2019-present: Associate Professor of Geophysics, Department of Earth, Environmental and Planetary Sciences, Brown University
2017-2019: Professor of Geophysics, Seismological Laboratory, California Institute of Technology
2011-2017: Assistant Professor of Geophysics, Seismological Laboratory, California Institute of Technology (Caltech)
2009-2011: Mendenhall Postdoctoral Fellow, Geologic Hazards Science Center, U.S. Geological Survey
2009: Postdoctoral Researcher, Dept. of Earth and Planetary Sciences, Harvard University

Education
Ph.D., Earth and Planetary Sciences (Geophysics), Harvard University, 2009
M.A., Earth and Planetary Sciences, Harvard University, 2006
B.S., Geophysics with Honors, California Institute of Technology, 2004

Collaborators (Current and Past): Greg Hirth, Sunyoung Park, Jack Muir, Quentin Brissaud, Michael Coughlin, Andreas Fichtner, Alex Robel, Vuk Mandic, Xiaozhou Ruan, Sue Hough, Voon Hui Lai, Mark Panning, Steve Vance, Matt Haney, Hsin-Hua Huang, Surendra Adhikari, Christine Dow, Andrew Stewart, Andy Thompson, Hilmar Gudmundsson, Daniel Bowden, Weian Chao, Mark Simons, Florent Gimbert, Naofumi Aso, Zhongwen Zhan, Brandon Schmandt, Pablo Ampuero, Mike Lamb, Fan-Chi Lin, Zacharie Duputel, Gavin Hayes, Jeff Love, Dan McNamara, Morgan Moschetti, Jim Rice, Adam Dziewonski, John Wettlaufer, Goran Ekstrom, David Stevenson, Hiroo Kanamori

Academic Interests
I am interested in many different aspects of solid earth geophysics, including but not limited to: earthquakes, glaciers, seismic imaging techniques, solid/fluid interactions, melting processes, earth structure, mantle convection, and planetary formation/processes. Some of my current projects include understanding and making use of noise correlation measurements, improving earthquake source parameterizations, creating new tomographic methods, modeling short-timescale glacier physics, using non-traditional seismic methods to constrain various geophysical phenomena, and modeling tsunamis. For more details about individual projects, click on the links below:

Publications
2020:

Lambert, V., and V. C. Tsai (2020). "Time-dependent stresses from fluid extraction and diffusion with applications to induced seismicity"
J. Appl. Mech., accepted (April, 2020).
Brissaud, Q., D. C. Bowden, and V. C. Tsai (2020). "Extension of the basin Rayleigh-wave amplification theory to include basin-edge effects"
Bull. Seismol. Soc. Am., doi:10.1785/0120190161, published (April, 2020).
Tsai, V. C., and G. Hirth (2020). "Elastic impact consequences for high-frequency earthquake ground motion"
Geophys. Res. Lett., 47, e2019GL086302, doi:10.1029/2019GL086302, published (March, 2020). PDF w/ Supp, Press Release, KBYU Interview, Quanta Magazine article
Muir, J. B., and V. C. Tsai (2020). "Did Oldham discover the core after all? Handling imprecise historical data with hierarchical Bayesian model selection"
Seismol. Res. Lett., 91, 1377-1383, doi:10.1785/0220190266. PDF
Muir, J. B. and V. C. Tsai (2020). "Geometric and level set tomography using ensemble Kalman inversion"
Geophys. J. Int., 220, 967-980, doi:10.1093/gji/ggz472. PDF
Haney, M. M. and V. C. Tsai (2020). "Perturbational and nonperturbational inversion of Love-wave velocities"
Geophys., 85, F19-F26, doi:10.1190/geo2018-0882.1. PDF (code available here)

2019:

Park, S., V. C. Tsai and M. Ishii (2019). "Frequency-dependent P-wave polarization and its subwavelength near-surface depth sensitivity"
Geophys. Res. Lett., 46, 14377-14384, doi:10.1029/2019GL084892. PDF
Brissaud, Q. and V. C. Tsai (2019). "Validation of a fast semi-analytic method for surface-wave propagation in layered media"
Geophys. J. Int., 219, 1405-1420, doi:10.1093/gji/ggz351. PDF
Farin, M., V. C. Tsai, M. P. Lamb, and K. Allstadt (2019). "A physical model of the high-frequency seismic signal generated by debris flows"
Earth Surf. Proc. Land., 44, 2529-2543, doi:10.1002/esp.4677. PDF
Meyers, P., D. C. Bowden, T. Prestegard, V. C. Tsai, V. Mandic, G. Pavlis, and R. Caton (2019). "Direct observations of surface-wave eigenfunctions at the Homestake 3D array"
Bull. Seismol. Soc. Am., 109, 1194-1202, doi:10.1785/0120190026. PDF
Coughlin, M., J. Harms, D. C. Bowden, P. Meyers, V. C. Tsai, V. Mandic, G. Pavlis, and T. Prestegard (2019). "Coherence-based approaches for estimating the composition of the seismic wavefield",
J. Geophys. Res., 124, 2941-2956, doi:10.1029/2018JB016608. PDF
Fichtner, A., and V. C. Tsai (2019). "Theoretical foundations of noise interferometry" in Seismic Ambient Noise,
N. Nakata, L. Gualtieri, A. Fichtner (eds.), Cambridge University Press, Cambridge. PDF
Gimbert, F., B. M. Fuller, M. P. Lamb, V. C. Tsai, and J. P. Johnson (2019). "Particle transport mechanics and induced seismic noise in steep flume experiments with accelerometer-embedded tracers"
Earth Surf. Proc. Land., 44, 219-241, doi:10.1002/esp.4495. PDF

2018:

Robel, A. A., and V. C. Tsai (2018). "A simple model for deglacial meltwater pulses"
Geophys. Res. Lett., 45, 11742-11750, doi:10.1029/2018GL080884. PDF
Mandic, V., V. C. Tsai, G. L. Pavlis, T. Prestegard, D. C. Bowden, P. Meyers, and R. Caton (2018). "A 3D broadband seismometer array experiment at the Homestake Mine"
Seismol. Res. Lett., 89, 2420-2429, doi:10.1785/0220170228. PDF
Tsai, V. C., and X. Ruan (2018). "A simple physics-based improvement to the positive degree day model"
J. Glaciol., 64, 661-668, doi:10.1017/jog.2018.55. PDF
Chen, H., V. C. Tsai, and F. Niu (2018). "Observations and modeling of long-period ground-motion amplification across northeast China"
Geophys. Res. Lett., 45, 5968-5976, doi:10.1029/2018GL078212. PDF
Lai, V. H., V. C. Tsai, M. P. Lamb, T. P. Ulizio, and A. R. Beer (2018). "The seismic signature of debris flows: flow mechanics and early warning at Montecito, California"
Geophys. Res. Lett., 45, 5528-5535, doi:10.1029/2018GL077683. PDF, Press Release, KPCC Interview, KABC-TV
Panning, M. P., S. C. Stahler, H.-H. Huang, S. D. Vance, S. Kedar, V. C. Tsai, W. T. Pike, and R. D. Lorenz (2018). "Expected seismicity and the seismic noise environment of Europa"
J. Geophys. Res., 123, 163-179, doi:10.1002/2017JE005332. PDF
Vance, S. D., S. Kedar, M. P. Panning, S. C. Stahler, B. G. Bills, R. D. Lorenz, H.-H. Huang, W. T. Pike, J. C. Castillo, P. Lognonne, V. C. Tsai, and A. R. Rhoden (2018). "Vital signs: Seismology of icy ocean worlds"
Astrobiology, 18, 37-53, doi:10.1089/ast.2016.1612. PDF

2017:

Bowden, D. C., V. C. Tsai, and F.-C. Lin (2017). "Amplification and attenuation across USArray using ambient noise wavefront tracking"
J. Geophys. Res., 122, 10086-10101, doi:10.1002/2017JB014804. PDF
Aso, N., V. C. Tsai, C. Schoof, G. E. Flowers, A. Whiteford, and C. Rada (2017). "Seismologically observed spatiotemporal drainage activity at moulins"
J. Geophys. Res., 122, 9095-9108, doi:10.1002/2017JB014578. PDF
Hough, S. E., V. C. Tsai, R. Walker, and F. Aminzadeh (2017). "Was the Mw 7.5 1952 Kern County, California, earthquake induced (or triggered)?"
J. Seismol., 21, 1613-1621, doi:10.1007/s10950-017-9685-x. PDF
Huang, H.-H., N. Aso, and V. C. Tsai (2017). "Toward automated directivity estimates in earthquake moment tensor inversion"
Geophys. J. Int., 211, 1084-1098, doi:10.1093/gji/ggx354. PDF
Muir, J. B., and V. C. Tsai (2017). "Rayleigh wave H/V via noise cross-correlation in southern California"
Bull. Seismol. Soc. Am., 107, 2021-2027, doi:10.1785/0120170051. PDF
Robel, A. A., V. C. Tsai, B. Minchew, and M. Simons (2017). "Tidal modulation of ice stream buttressing stresses"
Ann. Glaciol., 58, 12-20, doi:10.1017/aog.2017.22. PDF
Tsai, V. C., D. C. Bowden, and H. Kanamori (2017). "Explaining extreme ground motion in Osaka Basin during the 2011 Tohoku Earthquake"
Geophys. Res. Lett., 44, 7239-7244, doi:10.1002/2017GL074120. PDF
Haney, M. M., and V. C. Tsai (2017). "Perturbational and nonperturbational inversion of Rayleigh-wave velocities"
Geophys., 82, F15-F28, doi:10.1190/GEO2016-0397.1. PDF (code available here)
Schmandt, B., D. Gaeuman, R. Stewart, S. M. Hansen, V. C. Tsai, and J. Smith (2017). "Seismic array constraints on reach-scale bedload transport"
Geology, 45, 299-302, doi:10.1130/G38639.1. PDF
Bowden, D. C., and V. C. Tsai (2017). "Earthquake ground motion amplification for surface waves"
Geophys. Res. Lett., 44, 121-127, doi:10.1002/2016GL071885. PDF

2016:

Lin, Y.-Y., K.-F. Ma, H. Kanamori, T.-R. A. Song, N. Lapusta, and V. C. Tsai (2016). "Evidence for non-self-similarity of microearthquakes recorded at a Taiwan borehole seismometer array"
Geophys. J. Int., 206, 757-773, doi:10.1093/gji/ggw172. PDF
Bowden, D. C., M. D. Kohler, V. C. Tsai, and D. S. Weeraratne (2016). "Offshore Southern California lithospheric velocity structure from noise cross-correlation functions"
J. Geophys. Res., 121, 3415-3427, doi:10.1002/2016JB012919. PDF
Gimbert, F., V. C. Tsai, J. M. Amundson, T. C. Bartholomaus, and J. I. Walter (2016). "Subseasonal changes observed in subglacial channel pressure, size, and sediment transport"
Geophys. Res. Lett., 43, 3786-3794, doi:10.1002/2016GL068337. PDF

2015:

Huang, H.-H., F.-C. Lin, V. C. Tsai, and K. D. Koper (2015). "High-resolution probing of inner core structure with seismic interferometry"
Geophys. Res. Lett., 42, 10622-10630, doi:10.1002/2015GL066390. PDF
Haney, M. M., and V. C. Tsai (2015). "Nonperturbational surface-wave inversion: A Dix-type relation for surface waves"
Geophys., 80, EN167-EN177, doi:10.1190/GEO2014-0612.1. PDF
Gimbert, F., and V. C. Tsai (2015). "Predicting short-period, wind-wave-generated seismic noise in coastal regions"
Earth Planet. Sci. Lett., 426, 280-292, doi:10.1016/j.epsl.2015.06.017. PDF
Dow, C. F., B. Kulessa, I. C. Rutt, V. C. Tsai, S. Pimentel, S. H. Doyle, D. van As, K. Lindback, R. Pettersson, G. A. Jones, and A. Hubbard (2015). "Modeling of subglacial hydrological development following rapid supraglacial lake drainage"
J. Geophys. Res., 120, 1127-1147, doi:10.1002/2014JF003333. PDF
Rice, J. R., V. C. Tsai, M. C. Fernandes, and J. D. Platt (2015). "Time scale for rapid draining of a surficial lake into the Greenland Ice Sheet"
J. Appl. Mech., 82, 071001, doi:10.1115/1.4030325. PDF
Huang, H.-H., F.-C. Lin, B. Schmandt, J. Farrell, R. B. Smith, and V. C. Tsai (2015). "The Yellowstone magmatic system from the mantle plume to the upper crust"
Science, 348, 773-776, doi:10.1126/science.aaa5648. PDF w/ Supp.
Adhikari, S., and V. C. Tsai (2015). "A model for subglacial flooding through a preexisting hydrological network during the rapid drainage of supraglacial lakes"
J. Geophys. Res., 120, 580-603, doi:10.1002/2014JF003339. PDF
Tsai, V. C., and G. H. Gudmundsson (2015). "An improved model for tidally-modulated grounding-line migration"
J. Glaciol., 61, 216-222, doi:10.3189/2015JoG14J152. PDF
Tsai, V. C., A. L. Stewart, and A. F. Thompson (2015). "Marine ice sheet profiles and stability under Coulomb basal conditions"
J. Glaciol., 61, 205-215, doi:10.3189/2015JoG14J221. PDF and Press Release
Bowden, D. C., V. C. Tsai, and F.-C. Lin (2015). "Site amplification, attenuation and scattering from noise correlation amplitudes across a dense array in Long Beach, CA"
Geophys. Res. Lett., 42, 1360-1367, doi:10.1002/2014GL062662. PDF
Chao, W.-A., Y.-M. Wu, L. Zhao, V. C. Tsai, and C.-H. Chen (2015). "Seismologically determined bedload flux during the typhoon season"
Sci. Rep., 5, 8261, doi:10.1038/srep08261. PDF

2014:

Aso, N., and V. C. Tsai (2014). "Cooling magma model for deep volcanic long-period earthquakes"
J. Geophys. Res., 119, 8442-8456, doi:10.1002/2014JB011180. PDF
Thompson, J., M. Simons, and V. C. Tsai (2014). "Modeling the elastic transmission of tidal stresses to great distances inland in channelized ice streams"
The Cryosphere, 8, 2007-2029, doi:10.5194/tc-8-2007-2014. PDF
Gimbert, F., V. C. Tsai, and M. P. Lamb (2014). "A physical model for seismic noise generation by turbulent flow in rivers"
J. Geophys. Res., 119, 2209-2238, doi:10.1002/2014JF003201. PDF
Tsai, V. C., and S. Atiganyanun (2014). "Green's functions for surface waves in a generic velocity structure"
Bull. Seismol. Soc. Am., 104, 2573-2578, doi:10.1785/0120140121. PDF
Lin, F.-C., V. C. Tsai, and B. Schmandt (2014). "3-D crustal structure of the western United States: application of Rayleigh-wave ellipticity extracted from noise cross-correlations"
Geophys. J. Int., 198, 656-670, doi:10.1093/gji/ggu160. PDF
Zhan, Z., V. C. Tsai, J. M. Jackson, and D. V. Helmberger (2014). "Ambient noise correlation on the Amery Ice Shelf, East Antarctica"
Geophys. J. Int., 196, 1796-1802, doi:10.1093/gji/ggt488. PDF
Zhan, Z., H. Kanamori, V. C. Tsai, D. V. Helmberger, and S. Wei (2014). "Rupture complexity of the 1994 Bolivia and 2013 Sea of Okhotsk deep earthquakes"
Earth Planet. Sci. Lett., 385, 89-96, doi:10.1016/j.epsl.2013.10.028. PDF

2013:

Schmandt, B., R. C. Aster, D. Scherler, V. C. Tsai, and K. Karlstrom (2013). "Multiple fluvial processes detected by riverside seismic and infrasound monitoring of a controlled flood in the Grand Canyon"
Geophys. Res. Lett., 40, 4858-4863, doi:10.1002/grl.50953. PDF
Lin, F.-C., and V. C. Tsai (2013). "Seismic interferometry with antipodal station pairs"
Geophys. Res. Lett., 40, 4609-4613, doi:10.1002/grl.50907. PDF
Duputel, Z., V. C. Tsai, L. Rivera, and H. Kanamori (2013). "Using centroid time-delays to characterize source durations and identify earthquakes with unique characteristics"
Earth Planet. Sci. Lett., 374, 92-100, doi:10.1016/j.epsl.2013.05.024. PDF
Zhan, Z., V. C. Tsai, and R. W. Clayton (2013). "Spurious velocity changes caused by temporal variations in ambient noise frequency content"
Geophys. J. Int., 194, 1574-1581, doi:10.1093/gji/ggt170. PDF
Lin, F.-C., V. C. Tsai, B. Schmandt, Z. Duputel, and Z. Zhan (2013). "Extracting seismic core phases with array interferometry"
Geophys. Res. Lett., 40, 1049-1053, doi:10.1002/grl.50237. PDF
Tsai, V. C., J.-P. Ampuero, H. Kanamori, and D. J. Stevenson (2013). "Estimating the effect of elasticity and compressibility on tsunami speeds"
Geophys. Res. Lett., 40, 492-496, doi:10.1002/grl.50147. PDF
Ma, Y., R. W. Clayton, V. C. Tsai, and Z. Zhan (2013). "Locating a scatterer in the active volcanic area of Southern Peru from ambient noise cross-correlation"
Geophys. J. Int., 192, 1332-1341, doi:10.1093/gji/ggs103. PDF

2012:

Zhan, Z., D. Helmberger, M. Simons, H. Kanamori, W. Wu, N. Cubas, Z. Duputel, R. Chu, V. C. Tsai, J.-P. Avouac, K. W. Hudnut, S. Ni, E. Hetland, F. H. Ortega Culaciati (2012). "Anomalously steep dips of earthquakes in the 2011 Tohoku-Oki source region and possible explanations",
Earth Planet. Sci. Lett., 353-354, 121-133, doi:10.1016/j.epsl.2012.07.038. PDF
Duputel, Z., H. Kanamori, V. C. Tsai, L. Rivera, L. Meng, J.-P. Ampuero, and J. Stock (2012). "The 2012 Sumatra great earthquake sequence",
Earth Planet. Sci. Lett., 351-352, 247-257, doi:10.1016/j.epsl.2012.07.017. PDF
Meng, L., J.-P. Ampuero, J. Stock, Z. Duputel, Y. Luo, and V. C. Tsai (2012). "Earthquake in a maze: compressional rupture branching during the 2012 MW 8.6 Sumatra earthquake",
Science, 337, 724-726, doi:10.1126/science.1224030. PDF w/ Supp.
Lin, F.-C., B. Schmandt, and V. C. Tsai (2012). "Joint inversion of Rayleigh wave phase velocity and ellipticity using USArray: constraining velocity and density structure in the upper crust",
Geophys. Res. Lett., 39, L12303, doi:10.1029/2012GL052196. PDF
Lin, F.-C., V. C. Tsai, and M. H. Ritzwoller (2012). "The local amplification of surface waves: A new observable to constrain elastic velocities, density, and anelastic attenuation",
J. Geophys. Res., 117, B06302, doi:10.1029/2012JB009208. PDF
Tsai, V. C., and J. R. Rice (2012). "Modeling Turbulent Hydraulic Fracture Near a Free Surface",
J. Appl. Mech., 79, 031003, doi:10.1115/1.4005879. PDF
Tsai, V. C., B. Minchew, M. P. Lamb, and J.-P. Ampuero (2012). "A Physical Model for Seismic Noise Generation from Sediment Transport in Rivers",
Geophys. Res. Lett., 39, L02404, doi:10.1029/2011GL050255. PDF

2011:

Tsai, V. C., and D. E. McNamara (2011). "Quantifying the Influence of Sea Ice on Ocean Microseism using Observations from the Bering Sea, Alaska",
Geophys. Res. Lett., 38, L22502, doi:10.1029/2011GL049791. PDF
Love, J. L., K. Mursula, V. C. Tsai, and D. M. Perkins (2011). "Are Secular Correlations Between Sunspots, Geomagnetic Activity, and Global Temperature Significant?",
Geophys. Res. Lett., 38, L21703, doi:10.1029/2011GL049380. PDF
Tsai, V. C., G. P. Hayes, and Z. Duputel (2011). "Constraints on the Long-Period Moment-Dip Tradeoff for the Tohoku Earthquake",
Geophys. Res. Lett., 38, L00G17, doi:10.1029/2011GL049129. PDF
Tsai, V. C. (2011). "Understanding the Amplitudes of Noise Correlation Measurements",
J. Geophys. Res., 116, B09311, doi:10.1029/2011JB008483. PDF
Tsai, V. C. (2011). "A Model for Seasonal Changes in GPS Positions and Seismic Wave Speeds due to Thermoelastic and Hydrologic Variations",
J. Geophys. Res., 116, B04404, doi:10.1029/2010JB008156. PDF

2008-2010:

Love, J. J., V. C. Tsai, and J. L. Gannon (2010). "Averaging and sampling for magnetic-observatory hourly data",
Ann. Geophys., 28, 2079-2096, doi:10.5194/angeo-28-2079-2010. PDF
Tsai, V. C., and J. R. Rice (2010). "A Model for Turbulent Hydraulic Fracture and Application to Crack Propagation at Glacier Beds",
J. Geophys. Res., 115, F03007, doi:10.1029/2009JF001474. PDF
Tsai, V. C. (2010). "The Relationship Between Noise Correlation and the Green's Function in the Presence of Degeneracy and the Absence of Equipartition",
Geophys. J. Int., 182, 1509-1514, doi:10.1111/j.1365-246X.2010.04693.x. PDF
Tsai, V. C., and M. P. Moschetti (2010). "An Explicit Relationship Between Time-Domain Noise Correlation and Spatial Autocorrelation (SPAC) Results",
Geophys. J. Int., 182, 454-460, doi:10.1111/j.1365-246X.2010.04633.x. PDF
Tsai, V. C. (2009). "The Use of Simple Physical Models in Seismology and Glaciology",
Harvard University, Ph.D. Thesis, advised by J. R. Rice. PDF
Tsai, V. C. (2009). "On Establishing the Accuracy of Noise Tomography Travel-Time Measurements in a Realistic Medium",
Geophys. J. Int., 178, 1555-1564, doi:10.1111/j.1365-246X.2009.04239.x. PDF
Tsai, V. C., J. R. Rice, and M. Fahnestock (2008). "Possible Mechanisms for Glacial Earthquakes",
J. Geophys. Res., 113, F03014, doi:10.1029/2007JF000944. PDF
Joughin, I., I. Howat, R. B. Alley, G. Ekstrom, M. Fahnestock, T. Moon, M. Nettles, M. Truffer, and V. C. Tsai (2008).
"Ice-front variation and tidewater behavior on Helheim and Kangerdlugssuaq Glaciers, Greenland",
J. Geophys. Res., 113, F01004, doi:10.1029/2007JF000837. PDF

2004-2007:

Tsai, V. C. and J. S. Wettlaufer (2007). "Star Patterns on Lake Ice",
Physical Rev. E, 75, doi:10.1103/PhysRevE.75.066105. PDF
Tsai, V. C. and D. J. Stevenson (2007). "Theoretical Constraints on True Polar Wander",
J. Geophys. Res., 112, B05415, doi:10.1029/2005JB003923. PDF
Tsai, V. C. and G. Ekstrom (2007). "Analysis of Glacial Earthquakes",
J. Geophys. Res., 112, F03S22, doi:10.1029/2006JF000596. PDF
Ekstrom, G., M. Nettles, and V. C. Tsai (2006). "Seasonality and Increasing Frequency of Greenland Glacial Earthquakes",
Science, 311, 5768, 1756-1758, doi:10.1126/science.1122112. PDF
Tsai, V. C., M. Nettles, G. Ekstrom, and A. M. Dziewonski (2005). "Multiple CMT source analysis of the 2004 Sumatra earthquake",
Geophys. Res. Lett., 32 (17), L17304, doi:10.1029/2005GL023398. PDF
Tsai, V. C., H. Kanamori, and J. Artru (2004). "The morning glory wave of southern California",
J. Geophys. Res.-Solid Earth, 109 (B2), B02307, doi:10.1029/2003JB002596. PDF

Last update 11:15PM June 6, 2020