Seismic Damage in Conifers from Olympic and Yellowstone National Parks, United States

Abstract

Two Douglas-fir (Pseudotsuga menziesii) from Olympic NP exhibit signs of the M∼9 Cascadia earthquake of 26 January, 1700 (Atwater et al. 2005) and associated after-shocks on nearby faults. One lodgepole pine (Pinus contorta), sampled at the Madison River in Yellowstone NP shows damage associated with the 17 August, 1959 M7.5 earthquake or aftershocks (USGS 2008), and another appears to record the large earthquakes felt by the Hayden expedition on 22 August, 1871 at the north shore of Yellowstone Lake (Hayden 1872). Other, such evidence was noted in Yellowstone samples, and younger damage events were seen in western hemlock (Tsuga heterophilla) samples from Heart of the Hills in Olympic NP. The common characteristic of productive samples in both parks was that they were taken 6–24 m above ground level where stem whiplash produced by ground motion would be more likely to occur. It appears that such evidence has the potential to reveal unrecorded events; and perhaps epicenter locations.