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The Long-Lost Tale of an 18th-Century Tsunami, as Told by Trees Local evidence of the cataclysm has literally washed away over the years. But Oregon’s Douglas firs may have recorded clues deep in their tree rings. Max G. Levy, Wired Magazine, September 29, 2021 the paper is: Dziak, R. P., Black, B. A., Wei, Y., and Merle, S. G., 2021, Assessing local impacts of the 1700 CE Cascadia earthquake and tsunami using tree-ring growth histories: a case study in South Beach, Oregon, USA, Nat. Hazards Earth Syst. Sci., 21, 1971-1982. Related paper is; Patton, J. R., Goldfinger, C., Morey, A. E., Romsos, C., Black, B., Djadjadihardja, Y., and Udrekh: Seismoturbidite record as preserved at core sites at the Cascadia and Sumatra-Andaman subduction zones, Nat. Hazards Earth Syst. Sci., 13, 833-867. Yours, Paul H.

Below is a very interesting talk about tsunamis and how they are created. One quite interesting point that came up during the lecture and questions is that asteroid and meteorite impact are quite ineffective at creating tsunamis and the tsunamis threat from them has been greatly overestimated and the impact tsunamis shown in popular films is quite overexaggerated. Unusual Sources of Tsunamis From Krakatoa to Monterey Bay USGS 2017 January Evening Public Lecture, Eric Geist by Eric Geist, USGS Research Geophysicist https://www.youtube.com/watch?v=lSHBvb_QHrU Other very interesting USGS talks include: The Giant Cascadia Earthquake of January 26, 1700 July Evening Public Lecture 2015 Justin Rubinstein, USGS Research Geophysicist https://www.youtube.com/watch?v=AiojgMBQPBM Underwater Secrets of the Hayward Fault Zone: Integrated 3D imaging to understand earthquake hazards USGS 2017 May Evening Public Lecture https://www.youtube.com/watch?v=QaQVGOg6YMM The Cascadia talk discusses how subfossil trees were used to date the age of the last Cascadia Earthquake and tsunami. Yours, Paul H.