Coseismic Subsidence and Paleotsunami Run-Up Records from Latest Holocene Deposits in the Waatch Valley, Neah Bay, Northwest Washington, U.S.A.: Links to Great Earthquakes in the Northern Cascadia Margin

Coseismic Subsidence and Paleotsunami Run-Up Records from Latest Holocene Deposits in the Waatch Valley, Neah Bay, Northwest Washington, U.S.A.: Links to Great Earthquakes in the Northern Cascadia Margin

Peterson, C.D.; Cruikshank, K.M.; Darienzo, M.E.; Wessen, G.C.; Butler, V.L., and Sterling, S.L., 2013. Coseismic subsidence and paleotsunami run-up records from latest Holocene deposits in the Waatch Valley, Neah Bay, northwest Washington, U.S.A.: links to great earthquakes in the northern Cascadia...

Full description

Saved in:
Bibliographic Details
Published in:Journal of coastal research 2013-01, Vol.29 (1), p.157-172
Main Authors: Peterson, Curt D., Cruikshank, Kenneth M., Darienzo, Mark E., Wessen, Gary C., Butler, Virginia L., Sterling, Sarah L.
Format: Article
Language:eng
Subjects:
Alliances
Bogs
Coastal
Deposition
Diatoms
Earthquakes
Geodetic surveys
Grain size
Links
Marshes
Mud
Northwest
Peat
radiocarbon
Radiocarbon dating
RESEARCH PAPERS
Salinity
Seismic phenomena
Soil erosion
subduction zone
Subsidence
Subsidences (Earth movements)
Tsunami
Tsunamis
United States
Valleys
Wetlands
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Peterson, C.D.; Cruikshank, K.M.; Darienzo, M.E.; Wessen, G.C.; Butler, V.L., and Sterling, S.L., 2013. Coseismic subsidence and paleotsunami run-up records from latest Holocene deposits in the Waatch Valley, Neah Bay, northwest Washington, U.S.A.: links to great earthquakes in the northern Cascadia Margin. Representative shallow cores (1–2-m depth) from the Waatch Valley (n = 10) and from Neah Bay back-barrier wetlands (n = 7) record four coseismic subsidence events and associated paleotsunami inundations during the last 1300 years in the North Central Cascadia Margin. Three of the subsidence events (SUB1, SUB2b, and SUB3) correlate to reported great earthquakes dated at AD 1700, about 1.1 ka, and about 1.3 ka. An additional subsidence horizon (SUB2a), which is newly discovered in the study area, might correlate to a widely reported paleotsunami inundation, dated between 0.7 and 0.9 ka in the study region. The magnitudes of paleosubsidence in the Waatch Valley are modest (about 0.5−1.0 m), as based on macofossil evidence of abrupt wetland burial. Paleotsunami origins of the four landward thinning sand sheets are confirmed by the presence of ocean diatom taxa and beach sand grains. Long wave run-up in the low-gradient Waatch floodplain ranged from 2.5 to 4.5 km up-valley distance from the present tidal inlet shoreline. Paleotsunami overtopping of the Neah Bay barrier ridge (6–8-m elevation North American Vertical Datum of 1988 [NAVD88]) provides the first estimates of paleotsunami minimum run-up height at the entrance to the Juan de Fuca Strait.
ISSN:0749-0208
1551-5036