Honn Kao, Ph.D.

Image Kao, Honn
Research Scientist

Research Scientist, Seismology

Section Head, Section of Seismology, Tectonophysics, and Volcanology, Geological Survey of Canada - Pacific

Project Leader, Induced Seismicity Research Project, Environmental Geoscience Program

Current research and/or projects


Dr. Honn Kao obtained his BSc in Geophysics from the National Central University, Taiwan, in 1985, MSc and Ph.D. in Geophysics from the University of Illinois at Urbana-Champaign in 1991 and 1993, respectively. He was recruited by the Institute of Earth Sciences (IES), Academia Sinica, Taiwan, as an Assistant Research Fellow immediately after finishing his Ph.D. study. During his initial years at IES, he was in charge of establishing the Broadband Array in Taiwan for Seismology (BATS). He was promoted to Associate Research Fellow in 1996 and then Research Fellow in 2000. He was awarded the Outstanding Research Award of the National Research Council twice (1999 and 2001). In 2001, he was awarded the Distinguished Youth Medal of the Republic of China. He joined the Geological Survey of Canada in 2002 as a research scientist working on earthquake source characteristics and seismogenic structures. In 2006, he was appointed by the School of Earth and Ocean Sciences, University of Victoria, as an Adjunct Professor. He has served as an Associate Editor of the Journal of Geophysical Research between 2011 and 2017. He was also a member of the Editorial Board of the International Journal of Geophysics between 2012 and 2017. Currently, he is the Head of the Section of Seismology, Tectonophyscis, and Volcanology (SSTV), Geological Survey of Canada - Pacific, and the Leader of the Induced Seismicity Research Project of Natural Resources Canada.

Research and/or project statements

The theme of Dr. Honn Kao’s research is observational seismology. His current research activities focus on induced seismicity related to man-made activities, in particular, the development of unconventional oil and gas. He is the Project Leader of NRCan’s Induced Seismicity Research (ISR). In addition to ISR, Dr. Kao has also worked on a variety of topics at scales ranging from local to continental, including the delineation of earthquake source characteristics, determination of accurate velocity structures, seismic tomography, and seismotectonics. He maintains a database of centroid moment tensor (CMT) solutions for significant (M4+) earthquakes in and around Canada. He is also the inventor of many advanced seismological methods, including the Source-Scanning Algorithm (SSA) and the Depth-Scanning Algorithm (DSA), which have been used not only in earthquake source studies but also in studies of episodic tremor and slip (ETS) events, landslides, and mapping of earthquake rupture process.

Professional activities / interests

  • Associate Editor, Journal of Geophysical Research – Solid Earth (2011 – 2017).
  • Member, Editorial Board, International Journal of Geophysics (2012 – 2017).
  • Foreign Scientific Advisor, Central Weather Bureau, Taiwan (2013 – present).
  • International Advisory Board of the “Terrestrial, Atmospheric and Oceanic Sciences” Journal (2015 – present).

Education and awards

Natural Resources Canada Departmental Achievement Award for Impact and Contributions to Excellence in Science, 2019

Ph.D., Geophysics, University of Illinois at Urbana-Champaign, 1993

M.Sc., Geophysics, University of Illinois at Urbana-Champaign, 1991

B.Sc., Geophysics, National Central University, Taiwan, 1985


2019 Natural Resources Canada’s Departmental Achievement Award for impact and contributions to excellence in science

2011 NRCan Earth Science Sector Recognition Award

2007 Geological Survey of Canada Pacific Division Local Merit Award

2002 Outstanding Research Award, National Research Council, ROC Taiwan

2001 Distinguished Youth Medal, ROC Taiwan

2000 Outstanding Research Award, National Research Council, ROC Taiwan

Key publications

Selected Publications on Induced Seismicity

Wang B., H. Kao, R.M.H. Dokht, R. Visser, and H. Yu (2022). Delineating the controlling factors of hydraulic fracturing-induced seismicity in the Northern Montney Play, northeastern British Columbia, Canada, with machine learning, Seismol. Res. Lett., doi:10.1785/0220220075.

Wang, B., H. Kao, H. Yu, R. Visser, and S. Venables (2022). Physical factors controlling the diverse seismogenic behavior of fluid injections in western Canada, Earth and Planetary Science Letters, 589, 117555, doi:10.1016/j.epsl.2022.117555.

Eyre, T.S., S. Samsonov, W. Feng, H. Kao, and D.W. Eaton (2022). InSAR data reveal that the largest hydraulic fracturing-induced earthquake in Canada, to date, is a slow-slip event, Science Reports, 12, 2043, doi:10.1038/s41598-022-06129-3.

Gao, D., H. Kao, B. Wang, R. Visser, R. Schultz, and R.M. Harrington (2022). Complex 3D migration and delayed triggering of hydraulic fracturing-induced seismicity: A case study near Fox Creek, Alberta, Geophysical Research Letters, 49, e2021GL093979, doi:10.1029/2021GL093979.

Yu, H., H. Kao, R. Visser, and B. Wang (2021). Form seismic quiescence to surged activity after decades of wastewater disposal: A case study in central-west Alberta, Canada, Geophysical Research Letters, 48, e2021GL095074, doi: 10.1029/2021GL095074.

Yu, H., R.M. Harrington, H. Kao, Y. Liu, and B. Wang (2021). Fluid-injection induced earthquakes characterized by hybrid-frequency waveforms manifest the transition from aseismic to seismic slip, Nature Communications, 12, 6862, doi: 10.1038/s41467-021-26961-x.

Ojo, A. O., H. Kao, R. Visser, and C. Goerzen (2021). Spatiotemporal changes in seismic velocity associated with hydraulic fracturing-induced earthquakes near Fox Creek, Alberta, Canada. Journal of Petroleum Science and Engineering, 208, 109390, doi:10.1016/j.petrol.2021.109390.

Babaie Mahani, A., S. Venables, H. Kao, R. Visser, M. Gaucher, R.M.H. Dokht, and J. Johnson (2021). Intensity of induced earthquakes in northeast British Columbia, Canada, Seismol. Res. Lett., 92, 3482-3491, doi:10.1785/0220210037.

Dokht, R.M.H, H. Kao, A. Babaie Mahani, and R. Visser (2021). Spatiotemporal analysis of seismotectonic state of injection-induced seismicity clusters in the Western Canada Sedimentary Basin, Journal of Geophysical Research: Solid Earth, 126, e2020JB021362, doi:10.1029/2020JB021362.

Babaie Mahani, A., S. Venables, H. Kao, R. Visser, M. Gaucher, R.M.H. Dokht, and J. Johnson (2021). Intensity of induced earthquakes in northeast British Columbia, Canada, Seismol. Res. Lett., doi:10.1785/0220210037.

Wang, B., A. Verdecchia, H. Kao, R.M. Harrington, Y. Liu, and H. Yu (2021). A study on the largest hydraulic fracturing induced earthquake in Canada: numerical modeling and triggering mechanism, Bull. Seismol. Soc. Am.,doi:10.1785/0120200251.

Babaie Mahani, A., & Kao, H. (2020). Determination of Local Magnitude for Induced Earthquakes in the Western Canada Sedimentary Basin: An Update. Can. Soc. Explo. Gephys. Recorder, 45(2), https://csegrecorder.com/articles/view/determination-of-local-magnitude-for-induced-earthquakes-in-the-wcsb.

Dokht, R. M. H., Smith, B., Kao, H., Visser, R., & Hutchinson, J. (2020). Reactivation of an Intraplate Fault by Mine-Blasting Events: Implications to Regional Seismic Hazard in Western Canada. Journal of Geophysical Research: Solid Earth, 125(6), e2020JB019933. doi:10.1029/2020JB019933.

Babaie Mahani, A., F. Esfahani, H. Kao, M. Gaucher, M. Hayes, R. Visser, and S. Venables (2020). A systematic study of earthquake source mechanism and regional stress field in the southern Montney Unconventional Play of northeast British Columbia, Canada, Seismol. Res. Lett., 91(1), 195-206, doi: 10.1785/0220190230.

Wang, B., R.M. Harrington, Y. Liu, H. Kao, and H. Yu (2019). Remote dynamic triggering of earthquakes in three unconventional Canadian hydrocarbon regions based on a multi-station matched-filter approach, Bull. Seismol. Soc. Am., 109, 372-386, doi:10.1785/0120180164.

Kao, H., R. Hyndman, Y. Jiang, R. Visser, B. Smith, A. Babaie Mahani, L. Leonard, H. Ghofrani, and J. He (2018). Induced seismicity in western Canada linked to tectonic strain rate: Implications for regional seismic hazard, Geophys. Res. Lett., 45, 11104-11115, doi:10.1029/2018GL079288. (* featured by the Incorporated Research Institutions for Seismology, IRIS, as one of 2018-2019’s “Science Highlights”)

Barbaie Mahani, A., and H. Kao (2018). Accurate determination of local magnitude for earthquakes in the Western Canada Sedimentary Basin, Seismol. Res. Lett., 90, 203-211, doi:10.1785/0220180264.

Kao., H., R. Visser, B. Smith, and S. Venables (2018). Performance assessment of the induced seismicity traffic light protocol (IS-TLP) for northeastern British Columbia and western Alberta, The Leading Edge, 37(2), 117-126, doi: 10.1190/tle37020117.1.

Schultz, R., G. Atkinson, D. Eaton, Y.J. Gu, and H. Kao (2018). Hydraulic fracturing completion volume is associated with induced earthquakes in the Duvernay Play, Science, 359, 304-308, doi: 10.1126/science.aao0159.

Babaie Mahani, A., and H. Kao (2017). Ground motion from M1.5–3.8 induced earthquakes at hypocentral distance <45 km in the Montney Play of northeast British Columbia, Canada, Seismol. Res. Lett., 89, 22-34, doi:10.1785/0220170119.

Babaie Mahani, A., R. Schultz, H. Kao, D. Walker, J. Johnson, and C. Salas (2017). Fluid injection and seismic activity in the northern Montney Play, British Columbia, Canada, with special reference to the 17 August 2015 Mw 4.6 induced earthquake, Bull. Seismol. Soc. Am., 107, 542-552, doi:10.1785/0120160175.

Kao, H., D.W. Eaton, G.M. Atkinson, S. Maxwell, and A. Babaie Mahani (2016). Technical meeting on the traffic light protocol (TLP) for induced seismicity: Summary and recommendations, Geol. Surv. Canada, Open File 8075, 20 pp., doi:10.4095/299002.

Mahani, A. B., H. Kao, D. Walker, J. Johnson, and C. Salas (2016). Performance evaluation of the regional seismograph network in northeast British Columbia, Canada, for monitoring of induced seismicity, Seismol. Res. Lett., 87, 648-660, doi: 10.1785/0220150241.

Farahbod, A.M., H. Kao, J.F. Cassidy, and D. Walker (2015). How did hydraulic fracturing operations in the Horn River Basin change the seismicity patterns in northeast British Columbia, Canada? The Leading Edge, 34, 658–660, 662–663, doi:10.1190/tle34060658.1.

Farahbod, A.F., H. Kao, D.M. Walker, and J.F. Cassidy (2015). Investigation of regional seismicity before and after hydraulic fracturing in the Horn River Basin, northeast British Columbia, Can. J. Earth Sci., 52(2), 112-122, doi:10.1139/cjes-2014-0162.


Selected Publications on Earthquake Source Studies

Dokht, R.M.H., H. Kao, H. Ghofrani, and R. Visser (2022). Combining deep learning and the Source-Scanning Algorithm for improved seismic monitoring, Bull. Seismol. Soc. Am., doi:10.1785/0120220007.

Hsu, Y.-J., H. Kao, R. Bürgmann, Y.-T. Lee, H.-H. Huang, Y.-F. Hsu, Y.-M. Wu, and J. Zhuang (2021). Synchronized and asynchronous modulation of seismicity by hydrological loading: A case study in Taiwan, Science Advances7, eabf7282.

Gao, D., H. Kao, and B. Wang (2021). Misconception of waveform similarity in the identification of repeating earthquakes, Geophysical Research Letters, 48, e2021GL092815, doi:10.1029/2021GL092815.

Tan, F., H. Kao, E. Nissen, and Ryan Visser (2020). Tracking earthquake sequence in real time: Application of Seismicity-Scanning based on Navigated Automatic Phase-Picking (S-SNAP) to the 2019 Ridgecrest, California Sequence, Geophysical Journal International, 223(3), 1511-1524, doi:10.1093/gji/ggaa387.

Gao, D., and H. Kao (2020). Optimization of the match-filtering method for robust repeating earthquake detection: The multi-segment cross-correlation approach, Journal of Geophysical Research: Solid Earth, 125, e2020JB19714, doi:10.1029/2020JB019714..

Yuan, J., Kao, H., & Yu, J. (2020). Depth‐Scanning Algorithm: Accurate, Automatic, and Efficient Determination of Focal Depths for Local and Regional Earthquakes. Journal of Geophysical Research: Solid Earth, 125, e2020JB019430.

Tan, F., H. Kao, E. Nissen, and D. Eaton (2019). Seismicity-scanning based on navigated automatic phase-picking, J. Geophys. Res. Solid Earth, 124, doi:10.1029/2018JB017050.

Tan, F., Z. Ge, H. Kao, and E. Nissen (2019). Validation of the 3-D phase-weighted relative back projection technique and its application to the 2016 Mw 7.8 Kaikoura earthquake, Geophys. J. Int., 217, 375-388, doi:10.1093/gji/ggz032.

Dokht, R.M.H., H. Kao, R. Visser, and B. Smith (2019). Seismic event and phase detection using time-frequency representation and convolutional neural networks, Seismol. Res. Lett., 90(2A), 481-490, doi:10.1785/0220180308.

Kao, H., S.-J. Shan, and A.M. Farahbod (2015). Source characteristics of the 2012 Haida Gwaii earthquake sequence, Bull. Seismol. Soc. Am, 105, 1206-1218, doi:10.1785/0120140165.

Evangelidis, C. P., and H. Kao (2014). High-frequency source imaging of the 2011 October 23 Van (Eastern Turkey) earthquake by backprojection of strong motion waveforms, Geophys. J. Int., 196, 1060-1072, doi:10.1093/gji/ggt437.

Liao, Y.-C., H. Kao, A. Rosenberger, S.-K. Hsu, and B.-S. Huang (2012). Delineating complex spatiotemporal distribution of earthquake aftershocks: An improved Source-Scanning Algorithm, Geophys. J. Int., 189, 1753-1770, doi: 10.1111/j.1365-246X.2012.05457.x.

Kao, H., S.-J. Shan, A. Bent, C. Woodgold, G. Rogers, J. F. Cassidy, and J. Ristau (2012). Regional centroid-moment-tensor analysis for earthquakes in Canada and adjacent regions: An update, Seismol. Res. Lett., 83, 505-515, doi: 10.1785/gssrl.83.3.505.

Kan, C.-W., H. Kao, G.-B. Ou, R.-Y. Chen, and C.-H. Chang (2010). Delineating the rupture planes of an earthquake doublet using Source-Scanning Algorithm: Application to the 3 March 2005 Ilan doublet, northeast Taiwan, Geophys. J. Int., 182, 956-966, doi:10.1111/j.1365-246X.2010.04664.x.

Kao, H., K. Wang, R.-Y. Chen, I. Wada, J. He, and S.D. Malone (2008). Identifying rupture plane of the 2001 Nisqually, Washington, earthquake, Bull. Seismol. Soc. Am., 98, 1546-1558.

Kao, H., and S.-J. Shan (2007). Rapid identification of earthquake rupture plane using Source-Scanning Algorithm, Geophys. J. Int., 168, 1011-1020.

Kao, H., and S.-J. Shan (2004). The Source-Scanning Algorithm: mapping the distribution of seismic sources in time and space, Geophys. J. Int., 157, 589-594.

Kao, H., and W.-P. Chen (2000). The Chi-Chi earthquake sequence: Active, out-of-sequence thrust faulting in Taiwan, Science, 288, 2346–2349.

Kao, H., P.-R. Jian, K.-F. Ma, B.-S. Huang, and C.-C. Liu (1998). Moment-tensor inversion for offshore earthquakes east of Taiwan and their implications to regional collision, Geophys. Res. Lett., 25, 3619–3622.


Selected Publications on Velocity Structure Inversion, Tomography, and Seismotectonics

Hutchinson, J., H. Kao, M. Riedel, K. Obana, K. Wang, S. Kodaira, T. Takahashi, and Y. Yamamoto (2020). Significant geometric variation of the subducted plate beneath the northernmost Cascadia subduction zone and its tectonic implications as revealed by the 2014 Mw 6.4 earthquake sequence, Earth and Planetary Science Letters551, 116569, doi:10.1016/j.epsl.2020.116569.

Savard, G., M.G. Bostock, J. Hutchinson, H. Kao, N.I. Chirstensen, S.M. Peacock (2020), The northern terminus of Cascadia subduction, Journal of Geophysical Research: Solid Earth, 125, e2019JB018453, doi:10.1029/2019JB18453.

Cao, L., H. Kao, K. Wang, C. Chen, J. Mori, S. Ohmi, and Y. Gao (2019). Spatiotemporal variation of crustal anisotropy in the source area of the 2004 Niigata, central Japan, earthquake, Bull. Seismol. Soc. Am., doi:10.1785/20180195.

Kuponiyi, A. P., H. Kao, C. R. van Staal, S. E. Dosso, J. F. Cassidy, and G. D. Spence (2017). Upper crustal investigation of the Gulf of Saint Lawrence region, eastern Canada using ambient noise tomography, J. Geophys. Res. Solid Earth, 122, doi:10.1002/2016JB013865.

Cao, L., H. Kao, and K. Wang (2017). Contrasting upper-mantle shear wave anisotropy across the transpressive Queen Charlotte margin, Tectonophysics, 717, 311-320, doi:10.1016/j.tecto.2017.07.025.

Tonegawa, T., K. Obana, Y. Yamamoto, S. Kodaira, K. Wang, M. Riedel, H. Kao, and G. Spence (2016). Fracture alignments in marine sediments off Vancouver Island from Ps splitting analysis, Bull. Seismol. Soc. Am., 107, 387-402, doi: 10.1785/0120160090.

Kim, H. S., J. F. Cassidy, S. E. Dosso, and H. Kao (2014). Mapping crustal structure of the Nechako–Chilcotin plateau using teleseismic receiver function analysis, Can. J. Earth Sci., 51, 407-417, doi:10.1139/cjes-2013-0147.

Kao, H., Y. Behr, C. A. Currie, R. Hyndman, J. Townend, F.-C. Lin, M. H. Ritzwoller, S.-J. Shan, and J. He (2013). Ambient seismic noise tomography of Canada and adjacent regions: Part I. Crustal structures, J. Geophys. Res. Solid Earth, 118, 2013JB010535, doi:10.1002/2013JB010535.

Yeh, Y.-L., H. Kao, S. Wen, W.-Y. Chang, and C.-H. Chen (2013). Surface wave tomography and azimuthal anisotropy of the Philippine Sea Plate, Tectonophysics, 592, 94-112, doi: 10.1016/j.tecto.2013.02.005.

Kao, H., and P.-R. Jian (2001). Seismogenic patterns in the Taiwan region: Insights from source parameter inversion of BATS data, Tectonophysics, 333, 179-198.

Kao, H., and J. Angelier (2001). Stress tensor inversion for the Chi-Chi earthquake sequence and its implications on regional collision, Bull. Seismol. Soc. Am., 91, 1028-1040.

Kao, H., G.-C. Huang, and C.-S. Liu (2000). Transition from oblique subduction to collision in the northern Luzon arc–Taiwan region: Constraints from bathymetry and seismic observations, J. Geophys. Res., 105, 3059–3079.

Kao, H., S. J. Shen, and K.-F. Ma (1998). Transition from oblique subduction to collision: Earthquakes in the southernmost Ryukyu arc–Taiwan region, J. Geophys. Res., 103, 7211–7229.

Kao, H., and W.-P. Chen (1996). Seismicity in the outer-rise–fore-arc region and configuration of the subducting lithosphere with special reference to the Japan trench, J. Geophys. Res., 101, 27, 811–27,831.

Kao, H., and L. Liu (1995). A hypothesis for the seismogenesis of double seismic zone, Geophys. J. Int., 123, 71–84.

Kao, H., and W.-P. Chen (1994). The double seismic zone in Kuril–Kamchatka: The tale of two overlapping single zones, J. Geophys. Res., 99, 6913–6930.

Kao, H., and W.-P. Chen (1991). Earthquakes along the Ryukyu–Kyushu arc: strain segmentation, lateral compression,and the thermo-mechanical state of the plate interface, J. Geophys. Res., 96, 21,443–21,485.


Selected Publications on Episodic Tremor and Slip

Hyndman, R.D., P.A. McCrory, A. Wech, H. Kao, and J. Ague (2015). Cascadia subducting plate fluids channeled to fore-arc mantle corner: ETS and silica deposition, J. Geophys. Res. Solid Earth, 120, 4344–4358, doi:10.1002/ 2015JB011920.

Pollitz, F.F., A. Wech, H. Kao, R. Burgmann (2013). Annual modulation of non-volcanic tremor in northern Cascadia, J. Geophys. Res., 118, 2445-2459,doi:10.1002/jgrb.50181.

Kao, H., K. Wang, H. Dragert, J. Y. Kao, and G. Rogers (2010). Estimating seismic moment magnitude (Mw) of tremor bursts in northern Cascadia: Implications for the "seismic efficiency" of episodic tremor and slip, Geophys. Res. Lett., 37, L19306, doi:10.1029/2010GL044927.

Kao, H., S.-J. Shan, H. Dragert, and G. Rogers (2009). Northern Cascadia episodic tremor and slip: A decade of observations from 1997 to 2007, J. Geophys. Res., 114, B00A12, doi:10.1029/2008JB006046.

Kao, H., P. J. Thompson, G. Rogers, H. Dragert, and G. Spence (2007). Automatic detection and characterization of seismic tremors in northern Cascadia, Geophys. Res. Lett., 34, L16313, doi:10.1029/2007GL030822.

Kao, H., S.-J.Shan, G. Rogers, and H. Dragert (2007). Migration characteristics of seismic tremors in the northern Cascadia, Geophys. Res. Lett., 34, L03304, doi:10.1029/2006GL028430.

Kao, H., S.-J. Shan, H. Dragert, G. Rogers, J. F. Cassidy, K. Wang, T. James, and K. Ramachandran (2006). Spatial-temporal patterns of seismic tremors in northern Cascadia, J. Geophys. Res., 111, B03309, doi:10.1029/2005JB003727.

Kao, H., S.-J. Shan, H. Dragert, G. Rogers, J.F. Cassidy, and K. Ramachandran (2005). A wide depth distribution of seismic tremors along the northern Cascadia margin, Nature, 436, 841-844.


Selected Publications on Hazard Assessment, Landslides, and Other Topics

Ojo, A.O., H. Kao, Y. Jiang, M. Craymer, and J. Henton (2021). Strain accumulation and release rate in Canada: Implications for long-term crustal deformation and earthquake hazards, Journal of Geophysical Research: Solid Earth, 126, e2020JB020529, doi:10.1029/2020JB020529.

Kuponiyi, A.P., and H. Kao (2021). Temporal variation in cultural seismic noise and noise correlation functions during COVID-19 lockdown in Canada, Seismol. Res. Lett., doi:10.1785/0220200330.

Kao, H., C.-W. Kan, R.-Y. Chen, C.-H. Chang, A. Rosenberger, T.-C. Shin, P.-L. Leu, K.-W. Kuo, and W.-T. Liang (2012). Locating, monitoring, and characterizing typhoon-induced landslides with real-time seismic signals, Landslides, 9, doi:10.1007/s10346-012-0322-z.


All publications in NRCan’s GEOSCAN database

Research facility

9860 W. Saanich Road
Sidney, BC V8L 4B2


Member, Canadian Geophysical Union

Member, American Geophysical Union

Member, Seismological Society of America

Adjunct Professor, University of Victoria

Adjunct Research Fellow, Institute of Earth Sciences, Academia Sinica, Taiwan



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