Abstract
During the 1964 M9.2 great Alaskan earthquake, submarine-slope failures resulted in the generation of highly destructive tsunamis at Port Valdez, Alaska. A high-resolution, mini-sparker reflection profiler was used to image debris lobes, which we attribute to slope failures that occurred both during and prior to the 1964 megathrust event. In these reflection profiles, debris lobe deposits are indicated by acoustically opaque units that are separated by undisturbed parallel-layered reflectors. Near-surface debris lobes attributed to the 1964 earthquake include: (1) a debris lobe over 30 m thick that emanates from the fiord-head delta in eastern Port Valdez; and (2) debris flow lobes incorporating large, intact blocks up to 40 m high in western Port Valdez, off the Shoup Glacier moraine. In addition to the near-surface debris lobes, we imaged at least five additional debris lobe deposits buried beneath the 1964 deposit. The debris lobe directly beneath the 1964 deposit has a similar thickness and spatial distribution as the 1964 deposit. However, the older, deeper, debris lobes are thinner, less extensive, and separated by thinner sequences of parallel-layered reflectors. Glacier retreat and concomitant build-up of the fiord-head delta combined with longer time intervals between megathrust events may have resulted in more extensive delta failures and thus thicker debris lobes through time.
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References
Alexander CR, Venherm C (2003) Modern sedimentary processes in the Santa Monica, California continental margin: sediment accumulation, mixing and budget. Mar Environ Res 56:177–204
Beget J (2007) Earthquake, landslide and tsunami hazards in the Port Valdez area, Alaska. Consultation to the Prince William Sound Citizen's Advisory Council, Alaska Beget Consulting, Fairbanks, AK 55
Calkin PE, Wiles GC, Barclay DJ (2001) Holocene coastal glaciation of Alaska. Quat Sci Rev 20:449–461
Carver G, Plafker G (2008) Paleoseismicity and neotectonics of the Aleutian subduction zone - an overview. In: Freymueller JT, Haeussler PJ, Wesson RL, Ekström G (eds) Active Tectonics and Seismic Potential of Alaska, Geophys Monogr Ser 179. Am Geophys Union, Washington, 350 pp., ISBN 978-0-87590-444-3, AGU Code GM1794443
Cauchon-Voyer G, Locat J, St-Onge G (2008) Late-Quaternary morpho-sedimentology and submarine mass movements of the Betsiamites area, Lower St. Lawrence Estuary, Quebec, Canada. Mar Geol 251:233–252
Coulter HW, Migliaccio RR (1966) Effects of the earthquake of March 27, 1964 at Valdez, Alaska. US Geol Surv Prof Pap 542-C, 36
Jaeger JM, Nittrouer CA, Scott ND, Milliman JD (1998) Sediment accumulation along a glacially impacted mountainous coastline. Northeast Gulf of Alaska. Basin Res 10:155–173
Hampton MA, Lee HJ, Jocat J (1996) Submarine landslides. Rev Geophys 34:33–59
Hu FS, Ito E, Brown TA, Curry BB, Engstrom DR (2001) Pronounced climatic variations in Alaska during the last two millennia. Proc Natl Acad Sci 98:10552–10556
Lee HJ, Ryan HF, Kayen RE, Haeussler PJ, Dartnell P, Hampton MA (2006) Varieties of submarine failure morphologies of seismically-induced landslides in Alaskan fjords. Nor J Geol 86:221–230
Lee HJ, Ryan HF, Haeussler PJ, Kayen RE, Hampton MA, Locat J, Suleimani E, Alexander CR (2007) Reassessment of seismically induced, tsunamigenic submarine slope failures in Port Valdez, Alaska, USA. In: Lycousis V, Sakellarion D, and Locat J (eds) Submarine mass movements and their consequences, 357–365
Molnia BF (2008) Glaciers of North America - Glaciers of Alaska. In Williams RS Jr, and Ferrigno JG (eds) Satellite image atlas of glaciers of the world. US Geol Surv Prof Pap 1386-K, 525
Plafker G, Kachadoorian R, Eckel EB, Mayo LR (1969) Effects of the earthquake of March 27, 1964 on various communities. US Geol Surv Prof Pap 542-G, 50
Post A, Viens RJ (2000) Preliminary bathymetry of Shoup Basin and late Holocene changes of Shoup Glacier, Alaska. US Geol Surv Water-Resources Investig Rep 94–4093, 11
Reger RD (1990) Deglaciation of the Allison-Sawmill Creeks area, south shore of Port Valdez, Alaska. Alsk Div Geol Geop Surv, Public Data File 90–18, 10
Reyes AV, Wiles GC, Smith DJ, Allen S, Jackson S, Larocque S, Laxton S, Lewis D, Calkin PE, Clague JJ (2006) Expansion of alpine glaciers in Pacific North America in the first millennium A. D. Geology 34:57–60
Schnellmann M, Anselmetti FS, Giardini D, McKenzie JA, Ward SN (2002) Prehistoric earthquake history revealed by lacustrine slump deposits. Geology 30:1131–1134
Schnellmann M, Anselmetti FS, Giardini D, McKenzie JA (2005) Mass movement-induced fold-and-thrust belt structures in unconsolidated sediment in Lake Lucerne (Switzerland). Sedimentology 52:271–289
von Huene R, Shor GG Jr, Reimnitz E (1967) Geological interpretation of profiles in Prince William Sound, Alaska. Geol Soc Am Bull 78:259–268
Williams JR, Coulter HW (1981) Deglaciation and sea-level fluctuations in Port Valdez, Alaska. In: Albert NRD, Hudson T (eds) The United States Geological Survey in Alaska: Accomplishments during 1979, US Geol Surv Circ 823-B, B78–B80
Acknowledgments
We thank the Captain and crew of the R/V Norseman, Larry Kooker, Kevin O'Toole, Mike Torresan, Eric Grossman, Diane Minasian, Pat Hart, Jon Childs, Claudia Verheim, and Ray Sliter for their help in the acquisition and processing of both the seismic reflection and core data. We thank Michael Schnellmann and Eric Grist for their reviews, which helped improve the ideas presented in the paper.
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Ryan, H.F., Lee, H.J., Haeussler, P.J., Alexander, C.R., Kayen, R.E. (2010). Historic and Paleo-Submarine Landslide Deposits Imaged Beneath Port Valdez, Alaska: Implications for Tsunami Generation in a Glacial Fiord. In: Mosher, D.C., et al. Submarine Mass Movements and Their Consequences. Advances in Natural and Technological Hazards Research, vol 28. Springer, Dordrecht. https://doi.org/10.1007/978-90-481-3071-9_34
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DOI: https://doi.org/10.1007/978-90-481-3071-9_34
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