Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-27T13:24:23.916Z Has data issue: false hasContentIssue false
  • English
  • Français

Evidence for a Large Earthquake and Tsunami 100-400 Years Ago on Western Vancouver Island, British Columbia

Published online by Cambridge University Press:  20 January 2017

John J. Clague  and
Peter T. Bobrowsky
John J. Clague
Affiliation:
Geological Survey of Canada, 100 West Pender St., Vancouver, British Columbia V6B 1R8, Canada
Peter T. Bobrowsky
Affiliation:
Geological Survey Branch, Ministry of Energy, Mines and Petroleum Resources, 1810 Blanshard St., Victoria, British Columbia V8V 1X4, Canada
Get access Rights & Permissions [Opens in a new window]

Abstract

A peaty marsh soil is sharply overlain by a sand sheet and intertidal mud at tidal marshes near Tofino and Ucluelet, Vancouver Island, British Columbia. Foraminifera and vascular plant fossils show that the buried soil was submerged suddenly and was covered quickly by sand. Radiocarbon ages place this event between 100 and 400 yr ago. The coastal subsidence suggested by the submergence occurred in an area of net late Holocene emergence, perhaps during the most recent great earthquake on the northern part of the Cascadia subduction zone. The sand sheet overlying the peaty soil records the tsunami triggered by this earthquake. Similar stratigraphic sequences of about the same age have been reported from estuaries along the outer coasts of Washington and northern Oregon, suggesting that hundreds of kilometers of the Cascadia subduction zone may have ruptured during one, or a series of plate-boundary earthquakes less than 400 yr ago.

Type
Articles
Information
Quaternary Research , Volume 41 , Issue 2 , March 1994 , pp. 176 - 184
Copyright
University of Washington

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Adams, J. (1990). Paleoseismicity of the Cascadia subduction zone— Evidence from turbidites off the Oregon-Washington margin. Tectonics 9, 569–583.CrossRefGoogle Scholar
Atwater, B. F. (1987). Evidence for great Holocene earthquakes along the outer coast of Washington state. Science 236, 942–944.Google Scholar
Atwater, B. F. (1992). Geologic evidence for earthquakes during the past 2000 years along the Copalis River, southern coastal Washington. Journal of Geophysical Research 97, 1901–1919.CrossRefGoogle Scholar
Atwater, B. F., and Yamaguchi, D. K. (1991). Sudden, probably coseismic submergence of Holocene trees and grass in coastal Washington state. Geology 16, 706–709.Google Scholar
Atwater, B. F. Jim6nez Nunez, H., and Vita-Finzi, C. (1992). Net late Holocene emergence despite earthquake-induced submergence, south-central Chile. Quaternary International 15/16, 77–85.CrossRefGoogle Scholar
Atwater, B. F. Stuiver, M., and Yamaguchi, D. K. (1991). A radiocarbon test of earthquake magnitude at the Cascadia subduction zone. Nature 353, 156–158.CrossRefGoogle Scholar
Bard, E. Arnold, M. Fairbanks, R. G., and Hamelin, B. (1993). 230Th-2MU and 14C ages obtained by mass spectrometry of corals. Radiocarbon 35, 191–199.CrossRefGoogle Scholar
Bucknam, R. C. Hemphill-Haley, E., and Leopold, E. B. (1992). Abrupt uplift within the past 1700 years at southern Puget Sound, Washington. Science 258, 1611–1614.Google Scholar
Carver, G. A. Stuiver, M., and Atwater, B. F. (1992). Radiocarbon ages of earthquake-killed trees at Humboldt Bay, California. Eos (Transactions of the American Geophysical Union) 73, 398.Google Scholar
Clague, J. J., and Bobrowsky, P. T. (1990). Holocene sea level change and crustal deformation, southwestern British Columbia. In “Current Research, Part E,” Geological Survey of Canada Paper 90-IE, p. 245–250.Google Scholar
Clague, J. Harper, J. R. Hebda, R. J., and Howes, D. E. (1982). Late Quaternary sea levels and crustal movements, coastal British Columbia. Canadian Journal of Earth Sciences 19, 597–618.Google Scholar
Clarke, S. H. Jr., and Carver, G. A. (1992). Late Holocene tectonics and paleoseismicity, southern Cascadia subduction zone. Science 255, 188–192.CrossRefGoogle ScholarPubMed
Darienzo, M. E., and Peterson, C. D. (1990). Episodic tectonic subsidence of late Holocene salt marshes, northern Oregon coast, central Cascadia margin, U.S.A. Tectonics 9, 1–22.CrossRefGoogle Scholar
Dragert, H. Hyndman, R. D. Rogers, G. C., and Wang, K. (in press). Current deformation and the width of the seismogenic zone of the northern Cascadia subduction thrust. Journal of Geophysical Research. Google Scholar
Eronen, M. Kankainen, T., and Tsukada, M. (1987). Late Holocene sea level record in a core from the Puget Lowland, Washington. Quaternary Research 27, 147–159.CrossRefGoogle Scholar
Fisheries and Oceans (1992). “Canadian Tide and Current Tables 1993. Volume 6. Barkley Sound and Discovery Passage to Dixon Entrance.” Canada Department of Fisheries and Oceans, Ottawa.Google Scholar
Friele, P. A., and Hutchinson, I. (1993). Holocene sea-level change on the central west coast of Vancouver Island, British Columbia. Canadian Journal of Earth Sciences 30, 832–840.Google Scholar
Guilbault, J-P. (1992). “Foraminifera, Thecamoebians and Ostracodes from Holocene Localities on Southern Vancouver Island (1992 Campaign).” Unpublished report, Geological Survey of Canada, Vancouver.Google Scholar
Hutchinson, I. (1992). “Holocene Sea Level Change in the Pacific Northwest: A Catalogue of Radiocarbon Dates and an Atlas of Regional Sea Level Curves.” Simon Fraser University, Institute for Quaternary Research, Discussion Paper No. 1.Google Scholar
Hyndman, R. D., and Wang, K. (1993). Thermal constraints on the zone of major thrust earthquake failure: The Cascadia subduction zone. Journal of Geophysical Research 98, 2039–2060.Google Scholar
Long, D. Smith, D. E., and Dawson, A. G. (1989). A Holocene tsunami deposit in eastern Scotland. Journal of Quaternary Science 4, 61–66.CrossRefGoogle Scholar
Mclnelly, G. W., and Kelsey, H. M. (1990). Late Quaternary tectonic deformation in the Cape Arago-Bandon region of coastal Oregon as deduced from wave-cut platforms. Journal of Geophysical Research 95, 6699–6714.Google Scholar
Nelson, A. R. (1992). Holocene tidal-marsh stratigraphy in southcentral Oregon—evidence for localized sudden submergence in the Cascadia subduction zone. In “Quaternary Coasts of the United States: Marine and Lacustrine Systems” (Fletcher, C. H. III, and Wehmiller, J. F., Eds.), pp. 288–301. SEPM (Society for Sedimentary Geology) Special Publication No. 48.Google Scholar
Nelson, A. R., and Atwater, B. F. (1993). Radiocarbon dating of earthquake-killed plants along the Cascadia subduction zone. Eos (Transactions of the American Geophysical Union) 74, no. 43, October 26, 1993/supplement, 199–200.Google Scholar
Nelson, A. R., and Personius, S. F. (in press). The potential for great earthquakes in Oregon and Washington: An overview of recent coastal geologic studies and their bearing on segmentation of Holocene ruptures, central Cascadia subduction zone. In “Earthquake Hazards in the Pacific Northwest of the United States” (Rogers, A. M. Walsh, T. J. Kockelman, W. J., and Priest, G. R., Eds. ). U.S. Geological Survey Professional Paper 1560 (released in preliminary form in 1991 as U.S. Geological Survey Open-File Report 91-441).Google Scholar
Pearson, G. W. Becker, B., and Qua, F. (1993). High-precision 14C measurement of German and Irish oaks to show the natural 14C variations from 7890 to 5000 BC. Radiocarbon 35, 93–104.CrossRefGoogle Scholar
Peterson, C. D., and Darienzo, M. E. (in press). Discrimination of climatic, oceanic, and tectonic forcing of marsh burial events from Alsea Bay, Oregon, U.S.A. In “Earthquake Hazards in the Pacific Northwest of the United States” (Rogers, A. M. Walsh, T. J. Kockelman, W. J., and Priest, G. R., Eds.). U.S. Geological Survey Professional Paper 1560 (released in preliminary form in 1991 as U.S. Geological Survey Open-File Report 91-441).Google Scholar
Plafker, G. (1972). Alaskan earthquake of 1964 and Chilean earthquake of 1960—implications for arc tectonics. Journal of Geophysical Research 77, 901–925.CrossRefGoogle Scholar
Savage, J. C., and Lisowski, M. (1991). Strain measurements and the potential for a great subduction zone earthquake off the coast of Washington. Science 252, 101–103.Google Scholar
Scott, D. B., and Medioli, F. S. (1980). “Quantitative Studies of Marsh Foraminiferal Distributions in Nova Scotia: Implications for Sea Level Studies.” Cushman Foundation for Foraminiferal Research Special Publication No. 17.Google Scholar
Stuiver, M., and Pearson, G. W. (1993). High-precision bidecadal calibration of the radiocarbon time scale, AD 1950-500 BC and 25006000 BC. Radiocarbon 35, 1–23.Google Scholar
Yorath, C. J. (1992). Upper Jurassic to Paleogene assemblages. In “Geology of the Cordilleran Orogen in Canada” (Gabrielse, H. and Yorath, C. J., Eds.), pp. 329–371. Geological Survey of Canada, Geology of Canada, no. 4 (also Geological Society of America, The Geology of North America, v. G-2).Google Scholar