Sinking of volcanic ash in uncompacted sediment in Williams Lake, Washington

R.Y. Anderson; E.B. Nuhfer; W.E. Dean

doi:10.1126/science.225.4661.505

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Sinking of volcanic ash in uncompacted sediment in Williams Lake, Washington

R.Y. Anderson·E.B. Nuhfer·W.E. Dean

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Abstract

Volcanic ash from the eruption of Mount St. Helens on 18 May 1980 fell into Williams Lake in eastern Washington and was temporarily suspended at the sediment-water interface. After several months of compaction, the ash layer broke up and sank into lower density uncompacted lake sediment. Stratigraphic time displacements of several hundred years and a failure to recognize discontinuous ash layers in sediment cores are possible consequences of this process.

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Source-reported bounding extent: 47.31700552527329° to 47.336647953925194° latitude; -117.71303740955221° to -117.66661224970237° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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R.Y. Anderson, E.B. Nuhfer, W.E. Dean. 1984. Sinking of volcanic ash in uncompacted sediment in Williams Lake, Washington. https://doi.org/10.1126/science.225.4661.505

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