Optical dating studies of Quaternary organic-rich sediments from southwestern British Columbia and northwestern Washington State

The suitability of optical dating using 1.4 eV (infrared) excitation for determining the time of deposition, or compaction, of organic-rich sediments and peat is assessed with measurements on seven samples from six different lithostratigraphic units. One is of zero age, two have associated 14C ages, three are known to have been deposited during an interglaciation, and one is ~1 Ma old. The samples yield satisfactory optical ages ranging from 0 to over 100 ka. We conclude that the Muir Point Formation (southern Vancouver Island) and the Whidbey Formation (northwestern Washington State) were both deposited during δ18O stage 5, as previously deduced from other evidence. The age obtained from the ~1 Ma sample was significantly too low. The optical dating method is simpler and more precise than thermoluminescence dating, and is recommended for future work.

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Optical Dating of Tsunami-Laid Sands

Quaternary Research ◽

10.1006/qres.1996.0053 ◽

1996 ◽

Vol 46 (2) ◽

pp. 127-140 ◽

Cited By ~ 82

Author(s):

David J. Huntley ◽

John J. Clague

Keyword(s):

British Columbia ◽

Radiocarbon Dating ◽

Large Earthquake ◽

Vancouver Island ◽

Tsunami Source ◽

Cascadia Subduction Zone ◽

Stratigraphic Correlation ◽

Optical Dating ◽

Tsunami Measurements ◽

Infrared Excitation

The ages of some tsunami deposits can be determined by optical dating, a key requirement being that the deposits are derived from sediment that was reworked and exposed to daylight by tidal currents, waves, wind, or bioturbation during the last years before the tsunami. Measurements have been made using 1.4 eV (infrared) excitation of K-feldspar grains separated from samples of prehistoric tsunami sand sheets and modern analogs of tsunami source sediments at four sites in Washington state and British Columbia. Source sands gave equivalent doses indicative of recent exposure to daylight. Tsunami sand at Cultus Bay, Washington, yielded an optical age of 1285 ± 95 yr (calendric years before A.D. 1995, ±1σ). At 2σ, this age overlaps the range of from 1030 to 1100 yr determined through a combination of high-precision radiocarbon dating and stratigraphic correlation. Tsunami sands at three sites near Tofino and Port Alberni on Vancouver Island, British Columbia, have optical ages of 260 ± 20, 325 ± 25, and 335 ± 45 yr. Historical records and radiocarbon dating show that the sand at each of the three sites is between 150 and 400 yr old. These optical ages support the hypothesis that the Vancouver Island sands were deposited by a tsunami generated by a large earthquake on the Cascadia subduction zone about 300 yr ago.

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Southern Wakashan: Descriptive and Theoretical Perspectives

The Canadian Journal of Linguistics / La revue canadienne de linguistique ◽

10.1017/s0008413100004175 ◽

2007 ◽

Vol 52 (1-2) ◽

pp. 1-18

Author(s):

Henry Davis ◽

Rachel Wojdak

Keyword(s):

British Columbia ◽

Vancouver Island ◽

Washington State ◽

Linguistic Theory ◽

Special Volume ◽

Theoretical Perspectives ◽

Foundational Work ◽

Edward Sapir

This special volume of CJL/RCL is the first collection of papers devoted specifically to the Southern Wakashan languages Makah, Ditidaht (also known as Nitinat), and Nuu-chah-nulth (also known as Nootka). These three closely related languages form a continuum stretching from the northwest tip of Washington State to northwest Vancouver Island in British Columbia. The Southern Wakashan languages are remarkable for the typologically unusual traits they exhibit in virtually all areas of their grammars. These properties were first illuminated by Edward Sapir in his foundational work on Nuu-chah-nulth (1911, 1915, 1921; Sapir and Swadesh 1939), which helped thrust Wakashan to the forefront of early Amerindian scholarship. The papers brought together in this volume reflect a recent resurgence of interest in Southern Wakashan, and highlight the potential of lesser-studied languages to contribute to linguistic theory, as well as the range of insights that theoretically informed perspectives can bring to the grammatical description of these languages.

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On the application of a three-dimensional numerical model to the waters between Vancouver Island and the mainland coast of British Columbia and Washington State

Three-Dimensional Coastal Ocean Models - Coastal and Estuarine Sciences ◽

10.1029/co004p0149 ◽

1987 ◽

pp. 149-175 ◽

Cited By ~ 1

Author(s):

J. O. Backhaus ◽

P. B. Crean ◽

D. K. Lee

Keyword(s):

British Columbia ◽

Numerical Model ◽

Three Dimensional ◽

Vancouver Island ◽

Washington State

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Cascadiacarpa exilis sp. nov.: new fruits of Fagaceae from the Eocene of British Columbia

Botany ◽

10.1139/cjb-2013-0247 ◽

2014 ◽

Vol 92 (5) ◽

pp. 377-387 ◽

Cited By ~ 2

Author(s):

Randal A. Mindell ◽

Ruth A. Stockey ◽

Graham Beard

Keyword(s):

British Columbia ◽

North America ◽

Cellulose Acetate ◽

Transverse Section ◽

Vancouver Island ◽

Washington State ◽

Western North America ◽

Single Seed ◽

Fossil Genus ◽

Shape And Size

More than 800 permineralized fagaceous fruits have been studied from the Eocene Appian Way locality of Vancouver Island, British Columbia. These cupulate nuts are the most common fruits preserved at the locality. They occur in calcareous concretions and were studied using the cellulose acetate peel technique. Cupules are borne on a spiny stalk and are broadly ovate in both longitudinal and transverse section. Cupules are evalvate and have both branching and simple spines. A single, ovoid, sclerotic nut is enclosed entirely by the cupule, except at the apex, where a stylar protrusion is free from any surrounding tissues. The nut is bilocular with a glabrous endocarp lining. At maturity, a single seed occupies the locular cavity. The embryo is straight and no endosperm is evident. The single-fruited, spiny cupule is most similar to fruits of Fagaceae subfamily Castaneoideae. Bicarpellate fruits and a glabrous endocarp place them within the fossil genus Cascadiacarpa; however, they differ from Cascadiacarpa spinosa in nut wall anatomy, cupule ornamentation, shape, and size. Fruits of Cascadiacarpa exilis sp. nov. are compared with spiny, small compression and impression fossil fruits from the Eocene Taneum Creek locality of Washington State. The characters of the Washington State fossils overlap with those observed in the anatomically preserved Appian Way cupulate fruits and, as such, may represent compression and impression fossils of the same genus. The permineralized fruits document that evalvate, spiny, cupulate nuts of Fagaceae were present and common in the Eocene of western North America.

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Revisions to the stratigraphy and biochronology of the Upper Cretaceous Nanaimo Group, British Columbia and Washington State

Canadian Journal of Earth Sciences ◽

10.1139/e78-045 ◽

1978 ◽

Vol 15 (3) ◽

pp. 405-423 ◽

Cited By ~ 42

Author(s):

Peter D. Ward

Keyword(s):

British Columbia ◽

Field Data ◽

Upper Cretaceous ◽

Vancouver Island ◽

Washington State ◽

Island Region ◽

New Name ◽

Local Range

The stratigraphy of the Upper Cretaceous Nanaimo Group of the Vancouver Island region is revised on the bases of new fossil and field data. Previously unrecognized turbidite facies of the Haslam Formation are proposed as the new Cowichan Member of the Haslam Formation. This member either overlies or intertongues with the new Haslam Creek Member of the Haslam Formation. The Extension–Protection Formation is subdivided into three formations: the lower Extension Formation, the middle Pender Formation (new name) and the upper Protection Formation.The macrofossil zonal succession can be revised to include a new local-range zone superjacent to the Schmidti Zone and subjacent to the Vancouverense Zone named the Chicoensis Zone, based on the Nanaimo Group occurrences of Baculites chicoensis Trask and Submortoniceras chicoense (Trask). Another new zone is proposed superjacent to the Vancouverense Zone and subjacent to the Suciaensis Zone, named the Paciflcum Zone. This latter zone is based on the local Nanaimo Group ranges of Metaplacenticeras cf. M. pacificum (Smith) and Baculites rex Anderson.

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