pure and applied geophysics

, Volume 146, Issue 1, pp 5–20 | Cite as

Am improved source mechanism for the 1935 Timiskaming, Quebec earthquake from regional waveforms

  • Allison L. Bent


The Timiskaming earthquake, which occurred near the Quebec-Ontario border at the northwest end of the Western Quebec seismic zone in 1935, is one of the five largest instrumentally recorded southeastern Canadian earthquakes. Previous studies of this earthquake concentrated on modeling teismograms recorded at regional distances, a better constrained focal mechanism is obtained. The waveforms indicate thrust faulting on a moderately dipping northwest striking plane at a depth of 10 km. TheM w of 6.1 determined in this study is in good agreement with previous magnitude estimates (m b 6.1,M s 6.0, andm bLg 6.2–6.3). The focal mechanism is similar to those of many recent small to moderate earthquakes in the region, and the inferred (from theP axis) acting stress of northeast compression is consistent with the overall eastern North American stress field. The “Lake Timiskaming Rift Valley” in which the earthquake occurred, comprises several northwest striking faults consistent with the strike of the 1935 event. Thus, the 1935 earthquake appears to be a result of faulting on the reactivated Timiskaming graben.

Key words

Pnl waves historical earthquake Canadian earthquake 


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  1. Adam, J. (1991),New Focal Mechanisms for Eastern Canada, Geol. Surv. Canada Open File Rep.2430, 118 pp.Google Scholar
  2. Adams, J., andVonk, A. (1989),The November 1, 1935, M 6.2 Timiskaming Earthquake, its Aftershocks and Subsequent Seismicity, and Some Comparisons with the 1988 Saguenay Earthquake (abstract), Seism. Res. Lett.,60, 19.Google Scholar
  3. Adams, J., andBasham, P. (1991),The seismicity and seismotectonics of eastern North America. InNeotectonics of North America (Slemmons, D. B., Engdahl, E. R., Zoback, M. D., Blackwell, D. D., eds), Geol. Soc. Am., Decade Map Vol. 1 (Boulder CO, 1991), pp. 261–276.Google Scholar
  4. Adams, J., Sharp, J., andStagg, M. C. (1988),New Focal Mechanisms for Southeastern Canadian Earthquakes, vol I, Geol. Surv. Canada Open File Rep.1892, non-paginated.Google Scholar
  5. Adams, J., Vonk, A., Pittman, D. andVatcher, H. (1989),New Focal Mechanisms for Southeastern Canadian Earthquakes, vol. II, Geol. Surv. Canada Open File Rep.1995, non-paginated.Google Scholar
  6. Atkinson, G. M., andBoore, D. M. (1987),On the mN,M Relation for Eastern North American Earthquakes, Seism. Res. Lett.4, 119–124.Google Scholar
  7. Basham, P. W., Weichert, D. H. Anglin, F. M., andBerry, M. J. (1982),New Probabilistic Strong Seismic Ground Motion Maps of Canada: A Compilation of Earthquake Source Zones, Methods and Results, Earth Phys. Branch Open File Rep. 82-33, 202 pp.Google Scholar
  8. Bent, A. L. (1992),A Re-examination of the 1925 Charlevoix, Quebec Earthquake, Bull. Seismol. Soc. Am.82, 2097–2113.Google Scholar
  9. Bent, A. L. (1994a),The 1989 (M s 6.3) Ungava, Quebec Earthquake: A Complex Intraplate Event, Bull. Seismol. Soc. Am.84, 1075–1088.Google Scholar
  10. Bent, A. L. (1994b),Seismograms for Historic Canadian Earthquakes: The 1 November 1935 Timiskaming Earthquake, Geol. Surv. Can. Open File Rep. 2954, 20 pp.Google Scholar
  11. Bent, A. L., andHelmberger, (1989),Source Complexity of the October 1, 1987 Whittier Narrows Earthquake, J. Geophys. Res.94, 9548–9556.Google Scholar
  12. Charlier, C., andVan Gils, J. M. (1953),Liste de Stations Seismologiques Mondiales, Obs. Royale de Belgique, Uccle.Google Scholar
  13. Dewey, J. W., andGordon, D. W. (1984),Map of Recomputed Hypocenters of Earthquakes in the Eastern and Central United States and Adjacent Canada, U. S. Geol. Surv. Misc. Field Studies Map MF-1699.Google Scholar
  14. Doig, R. (1991),Effects of Seismic Shaking in Lake Sediments, and Earthquake Recurrence Interval, Témiskaming, Quebec, Can. J. Earth Sci.,28, 1349–1352.Google Scholar
  15. Ebel, J. E., Somerville, P. G., andMcIver, J. D. (1986),A Study of the Source Parameters of Some Large Earthquakes of Northeastern North America, J. Geophys. Res.91, 8231–8247.Google Scholar
  16. Forsyth, D., Morel, P., Hasegawa, H., Wetmiller, R., Adams, J., Goodarce, A., Nagy, D., Coles, R., Harris, J. andBasham, P. (1983),Comparative Study of the Geophysical and Geological Information in the Timiskaming-Kapuskasing Area, Atomic Energy of Canada Ltd. Technical RecordTR238, 1–52.Google Scholar
  17. Helmberger, D. V., andEngen, G. R. (1980),Modeling the Long-period Body Waves from Shallow Earthquakes at Regional Ranges, Bull. Seismol. Soc. Am.70, 1699–1714.Google Scholar
  18. Hodgson, E. A. (1935),Preliminary Report of the Earthquake of November 1, 1935, Earthquake Notes7, 1–4.Google Scholar
  19. Hodgson, E. A. (1936),The Timiskaming Earthquake of November 1, 1935: The Location of the Epicenter and Determination of Focal Depth, J. R. Astr. Soc. Can.30, 113–123.Google Scholar
  20. Hodgson, E. A. (1937),Timiskaming Earthquake Data and Time-distance Curves for Dilatational Waves, Trans. AGU18, 116–118.Google Scholar
  21. Hodgson, E. A. (1945),Industrial Earthquake Hazards in Eastern Canada, Bull. Seismol. Soc. Am.35, 151–174.Google Scholar
  22. Kumarapeli, P. S., andSaull, V. A. (1966),The St. Lawrence Valley System: A North American Equivalent of the East African Rift Valley Syst Valley System, Can. J. Earth Sci.3, 639–658.Google Scholar
  23. Lamontagne, M., Hasegawa, H. S., Forsyth, D. A., Buchbinder, G. G. R., andCajka, M. (1994),The Mont-Laurier, Quebec, Earthquake of 19 October 1990 and its Seismotectonic Environment, Bull. Seismol. Soc. Am.84, 1506–1522.Google Scholar
  24. Lovell, H. L., andCaine, T. W. (1970),Lake Timiskaming Rift Valley, Ontario Dept. Mines Misc. Paper39, 1–16.Google Scholar
  25. Mansinha, L., andSmylie, D. E. (1971),The Displacement Fields of Inclined Faults, Bull. Seismol. Soc. Am.82, 1433–1440.Google Scholar
  26. Shilts, W. W., andClague, J. J. (1992),Documentation of Earthquake-induced Disturbance of Lake Sediments Using Subbottom Acoustic Profiling, Can. J. Earth Sci.29, 1018–1042.Google Scholar
  27. Street, R., andTurcotte, F. T. (1977),A Study of Northeastern North American Spectral Moments, Magnitudes and Intensities, Bull Seismol. Soc. Am.67, 599–614.Google Scholar
  28. Wahlström, R. (1987),Focal Mechanisms of Earthquakes in Southern Quebec, Southeastern Ontario, and Northeastern New York with Implications for Regional Seismotectonics and Stress Field Characteristics, Bull. Seismol. Soc. Am.,77, 891–924.Google Scholar
  29. Wallace, T. C., andHelmberger, D. V. (1982),Determining Source Parameters of Moderate-sized Earthquakes from Regional Waveforms, Phys. Earth Planet. Int.30, 185–196.Google Scholar
  30. Zoback, M. L. (1992),Stress Field Constraints on Intraplate Seismicity in Eastern North America, J. Geophys. Res.97, 11761–11782.Google Scholar

Copyright information

© Birkhäuser Verlag 1996

Authors and Affiliations

  • Allison L. Bent
    • 1
  1. 1.Geophysics DivisionGeological Survey of CanadaOttawaCanada

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