Preliminary estimates of recurrence intervals for great earthquakes of the past 3500 years at northeastern Willapa Bay, Washington

Tectonic environments, recent stress and crustal strain observations, and historical descriptions of geomorphological changes and eyewitness accounts of the 1762 Bengal earthquake suggest that great earthquakes (M 8.0 or larger) can occur along the northward continuation of the 2004 Sumatra-Andaman earthquake. We describe marine terraces along the Rakhine coast of Myanmar as evidence for three great earthquakes in the past 3400 years. Radiocarbon dating of coral remains suggests that the oldest terrace emerged three times, during 1395–740 BC, AD 805–1220 and AD 1585–1810. We assign the youngest age to the 1762 earthquake, which reportedly raised parts of the Burmese coast by 3–7 m. These indicate that the great subduction-zone earthquakes have repeatedly occurred west off Myanmar with an average recurrence interval of about 1000–2000 years. The time since the last earthquake, ~ 250 years, is much shorter than the average interval, hence the chance of next earthquakes in the near future may be considered as low. However, the variability in both uplift amounts and recurrence intervals suggests the next great earthquake could happen sooner or later than would be expected from the average interval.

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Stress drops, wave spectra and recurrence intervals of great earthquakes - implications of the Etorofu earthquake of 1958 November 6

Geophysical Journal International ◽

10.1111/j.1365-246x.1979.tb03769.x ◽

1979 ◽

Vol 57 (1) ◽

pp. 23-40 ◽

Cited By ~ 45

Author(s):

Y. Fukao ◽

M. Furumoto

Keyword(s):

Wave Spectra ◽

Great Earthquakes ◽

Recurrence Intervals ◽

Stress Drops

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Paleoecological evidence for coastal subsidence during five great earthquakes in the past 1500 years along the northern onshore continuation of the Nankai subduction zone

Quaternary International ◽

10.1016/j.quaint.2015.11.014 ◽

2016 ◽

Vol 397 ◽

pp. 523-540 ◽

Cited By ~ 10

Author(s):

Osamu Fujiwara ◽

Shigehiro Fujino ◽

Junko Komatsubara ◽

Yoshimune Morita ◽

Yuichi Namegaya

Keyword(s):

Subduction Zone ◽

The Past ◽

Great Earthquakes ◽

Nankai Subduction Zone

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Great earthquakes of variable magnitude at the Cascadia subduction zone

Quaternary Research ◽

10.1016/j.yqres.2006.02.009 ◽

2006 ◽

Vol 65 (3) ◽

pp. 354-365 ◽

Cited By ~ 87

Author(s):

Alan R. Nelson ◽

Harvey M. Kelsey ◽

Robert C. Witter

Keyword(s):

Subduction Zone ◽

Plate Boundary ◽

Conclusive Evidence ◽

Cascadia Subduction Zone ◽

Radiocarbon Age ◽

Rupture Length ◽

Great Earthquakes ◽

Varying Length ◽

Recurrence Intervals ◽

Coseismic Subsidence

AbstractComparison of histories of great earthquakes and accompanying tsunamis at eight coastal sites suggests plate-boundary ruptures of varying length, implying great earthquakes of variable magnitude at the Cascadia subduction zone. Inference of rupture length relies on degree of overlap on radiocarbon age ranges for earthquakes and tsunamis, and relative amounts of coseismic subsidence and heights of tsunamis. Written records of a tsunami in Japan provide the most conclusive evidence for rupture of much of the plate boundary during the earthquake of 26 January 1700. Cascadia stratigraphic evidence dating from about 1600 cal yr B.P., similar to that for the 1700 earthquake, implies a similarly long rupture with substantial subsidence and a high tsunami. Correlations are consistent with other long ruptures about 1350 cal yr B.P., 2500 cal yr B.P., 3400 cal yr B.P., 3800 cal yr B.P., 4400 cal yr B.P., and 4900 cal yr B.P. A rupture about 700–1100 cal yr B.P. was limited to the northern and central parts of the subduction zone, and a northern rupture about 2900 cal yr B.P. may have been similarly limited. Times of probable short ruptures in southern Cascadia include about 1100 cal yr B.P., 1700 cal yr B.P., 3200 cal yr B.P., 4200 cal yr B.P., 4600 cal yr B.P., and 4700 cal yr B.P. Rupture patterns suggest that the plate boundary in northern Cascadia usually breaks in long ruptures during the greatest earthquakes. Ruptures in southernmost Cascadia vary in length and recurrence intervals more than ruptures in northern Cascadia.

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Great Earthquakes and Tsunamis of the Past 2000 Years at the Salmon River Estuary, Central Oregon Coast, USA

Bulletin of the Seismological Society of America ◽

10.1785/012003210 ◽

2004 ◽

Vol 94 (4) ◽

pp. 1276-1292 ◽

Cited By ~ 17

Author(s):

A. R. Nelson

Keyword(s):

River Estuary ◽

Oregon Coast ◽

Salmon River ◽

The Past ◽

Great Earthquakes ◽

Past 2000 Years

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Animism as a Means of Exploring Archaeological Fishing Structures on Willapa Bay, Washington, USA

Cambridge Archaeological Journal ◽

10.1017/s0959774310000028 ◽

2010 ◽

Vol 20 (1) ◽

pp. 17-32 ◽

Cited By ~ 27

Author(s):

Robert Losey

Keyword(s):

North America ◽

Northwest Coast ◽

Social Worlds ◽

Willapa Bay ◽

The Past ◽

Fish Traps ◽

The Social

Remnants of stationary fishing structures on the Northwest Coast of North America are commonly investigated by archaeologists, with most studies focusing on questions of function and chronology. Here it is argued that in Native Northwest Coast ontologies fish and fishing structures were considered animate and part of the social worlds within which humans and fish were engaged. Fish were considered capable of retaliating against those who treated them improperly, and one way of ensuring that no offence would occur was to dismantle fish traps when they were not in use. Using recently documented archaeological fishing structures on Willapa Bay, Washington, USA, as examples, it is argued that these and many other Northwest Coast archaeological fish traps were partially dismantled in the past.

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Combining inland and offshore paleotsunamis evidence: the Augusta Bay (eastern Sicily, Italy) case study

Natural Hazards and Earth System Science ◽

10.5194/nhess-12-2557-2012 ◽

2012 ◽

Vol 12 (8) ◽

pp. 2557-2567 ◽

Cited By ~ 20

Author(s):

A. Smedile ◽

P. M. De Martini ◽

D. Pantosti

Keyword(s):

Geological Evidence ◽

Tsunami Inundation ◽

The Past ◽

Bay Area ◽

History Of ◽

Continuous Sedimentation ◽

Recurrence Intervals ◽

Run Up ◽

Tsunami Recurrence

Abstract. Offshore and inland geological evidence for multiple tsunami inundations was found in the Augusta Bay area: (1) the main local historical tsunamis (1908, 1693, 1169), (2) two far-generated tsunamis (i.e. Crete 365 AD and Santorini, 3600 BP), and (3) seven unknown tsunamis). Average tsunami recurrence intervals from inland and offshore investigations of about 550 and 320 yr, respectively were obtained for the past 4 ka. The history of paleotsunamis from the marine record appears to be as complete as the historical one for the past millennium, yielding an average tsunami recurrence interval of 250 yr for the Augusta Bay. Geological data allow also estimating a minimum tsunami inundation distance of 530 m and a minimum run-up of 5 m. The marine record contains evidence for more paleotsunamis with respect to the inland one because of continuous sedimentation and better preservation of stratigraphy in the offshore with respect to coastal areas, which are commonly affected by intermittent-erosion and sedimentation and anthropic activities. This work shows that the integration of geological and historical data can provide critical information regarding the extent and age of tsunamis of the past (e.g. inundation distance, age, and frequency), which is of immediate relevance for tsunami hazard assessment.

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