Age of the Last Major Scabland Flood of the Columbia Plateau in Eastern Washington
Autor: | Donal Ray Mullineaux, Meyer Rubin, Walter F. Ebaugh, Roald Fryxell, Ray E. Wilcox |
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Rok vydání: | 1978 |
Předmět: |
Hydrology
Delta 010506 paleontology geography Plateau geography.geographical_feature_category Peat 010504 meteorology & atmospheric sciences Flood myth 01 natural sciences law.invention Arts and Humanities (miscellaneous) law Pumice General Earth and Planetary Sciences Physical geography Glacial period Radiocarbon dating Bog Geology 0105 earth and related environmental sciences Earth-Surface Processes |
Zdroj: | Quaternary Research. 10:171-180 |
ISSN: | 1096-0287 0033-5894 |
DOI: | 10.1016/0033-5894(78)90099-6 |
Popis: | Pumice layers of set S from Mount St. Helens can be correlated with certain ash beds associated with young flood deposits of the channeled scabland. The correlation points to an age of about 13,000 14C yr B.P. for the last major flood to have crossed the scabland. Until recently, the last major episode of flooding was thought to be closer to 20,000 yr B.P., an age inferred chiefly from the relation of the flood to glacial events of the northern Rocky Mountains. Several investigations within the last few years have suggested that the last major flood occurred well after 20,000 yr B.P. Tentative correlations of ash beds of the scabland with set S pumice layers, the relations of flood and glacial events along the northwestern margin of the Columbia Plateau, and a radiocarbon date from the Snake River drainage southeast of the plateau all indicate an age much younger than 20,000 yr. The postulated age of about 13,000 yr B.P. is further supported by a radiocarbon date in the Columbia River valley downstream from the scabland tract. Basal peat from a bog on the Portland delta of Bretz, which is a downvalley deposit of the last major scabland flood, has been dated as 13,080 ± 300 yr B.P. (W-3404). |
Databáze: | OpenAIRE |
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