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TitleA new high-resolution radiocarbon Bayesian age model of the Holocene and Late Pleistocene from core MD02-2494 and others, Effingham Inlet, British Columbia, Canada; with an application to the paleoseismic event chronology of the Cascadia Subduction Zone
AuthorEnkin, R J; Dallimore, A; Baker, J; Southon, J R; Ivanochko, T
SourceCanadian Journal of Earth Sciences vol. 50, 2013 p. 746-760,
Alt SeriesEarth Sciences Sector, Contribution Series 20120199
PublisherNRC Research Press
Mediapaper; on-line; digital
File formatpdf
ProvinceBritish Columbia
AreaEffingham Inlet
Lat/Long WENS-125.0000 -124.7500 49.2500 49.0000
Subjectsgeophysics; marine geology; sedimentology; Holocene; magnetic susceptibility; sediments; cores; radiocarbon dates; sedimentation rates; erosion; seismicity; Cascadia Subduction Zone; core MD02-2494; seismites; Quaternary
ProgramTargeted Hazard Assessments in Western Canada, Public Safety Geoscience
AbstractAnnually laminated sediments from the anoxic inner basin of Effingham Inlet, Pacific coast of Vancouver Island, British Columbia, Canada, yield a high-resolution 42mpaleoenvironmental record, from the present to about 14 ka 14C BP (17 ka cal BP). A new age model, based on 68 radiocarbon dates from twigs and small plant material, from the 40mcore MD02-2494 and 2 m freeze cores from the surface, is anchored by the Mazama Ash and varve counting. A Poisson-process sedimentation model is used, applying a new method to determine the Poisson k value, giving a realistic age model compatible with the multi-proxy core data. Twenty-one "seismites", which are lithofacies in the Effingham cores that may be representative of seismically triggered mass-wasting events, are identified and dated precisely, then compared with the chronology of the deep-sea turbidite record farther south in the Cascadia Subduction Zone (CSZ), to determine if regional sediment disturbances can be identified.
With 16 proposed correlations, Effingham seismite ages are 169 ± 206 years older than turbidite ages estimated largely by radiocarbon analysis of foraminifera in hemipelagic deposits.