| Title | Provenance and deposition of glacial Lake Missoula lacustrine and flood sediments determined from rock magnetic properties |
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| Author | Hanson, M A; Enkin, R J ; Barendregt, R W; Clague, J J |
| Source | Quaternary Research (New York) vol. 83, 1, 2015 p. 166-177, https://doi.org/10.1016/j.yqres.2014.09.005  Open Access |
| Year | 2015 |
| Alt Series | Natural Resources Canada, Contribution Series 20182251 |
| Publisher | Cambridge University Press (CUP) |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Program | GEM: Geo-mapping
for Energy and Minerals |
| Released | 2017 01 20 |
| Abstract | Repeated outburst flooding from glacial Lake Missoula, Montana, affected large areas of Washington during Marine Oxygen Isotope Stage 2 (29-14. ka). We present the first high-resolution rock magnetic
results from two sites that are critical to interpreting these outburst floods and that provide evidence of sediment provenance: glacial Lake Missoula, the source of the floods; and glacial Lake Columbia, where floodwaters interrupted sedimentation.
Magnetic carriers in glacial Lake Missoula varves are dominated by hematite, whereas those in outburst flood sediments and glacial Lake Columbia sediments are mainly magnetite and titano-magnetite. Stratigraphic variation of magnetic parameters is
consistent with changes in lithology. Importantly, magnetic properties highlight depositional processes in the flood sediments that are not evident in the field. In glacial Lake Columbia, hematite is present in fine silt and clay deposited near the
end of each flood as fine sediment settled out of the water column. This signal is only present at the end of the floods because the hematite is concentrated in the finer-grained sediment transported from the floor of glacial Lake Missoula, the only
possible source of hematite, ~. 240. km away. © 2014 University of Washington. |
| GEOSCAN ID | 310821 |
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