Serpent Spirit-power Stories along the Seattle Fault R. S. Ludwin1 , C. P. Thrush2 , K. James3 , D. Buerge4 , C. JonientzTrisler5 , J. Rasmussen6 , K. Troost1 , and A. de los Angeles7 INTRODUCTION The Seattle Fault is a multistranded east-west-striking reverse fault cutting across Puget Sound, through downtown Seattle, and across Lake Washington. Although geophysical evidence has long indicated a substantial offset in basement rocks beneath Puget Sound (Danes et al., 1965), no clear pattern of recent earthquake activity defining the fault has been observed. Geologic evidence of an earthquake around A.D. 900 (estimated magnitude 7.3) came to light in the early 1990’s (Bucknam et al., 1992), however, and the Seattle Fault is now recognized as a substantial hazard to the Seattle urban area. The circa A.D. 900 earthquake caused 7 m of vertical uplift on the southern side, sent massive block landslides tumbling into Lake Washington, and created a tsunami in Puget Sound that left sand deposits on Southern Whidbey Island (Atwater and Moore, 1992). Two archaeological sites near Seattle attest to the effects of such events on local indigenous communities. Excavations at West Point, a promontory jutting out into Puget Sound north of downtown that was used as a fish- and shellfish-processing site since at least at least 4,000 years before the present, show that that the area dropped at least a meter during the quake. The point’s marshes were flooded with saltwater and a layer of sand covered the entire site. Over time, people returned to West Point and began using it as they had before the quake (Larson and Lewarch, 1995). The earthquake also had the capacity to transform some locales permanently. At the Duwamish No. 1 archaeological site, excavations show that the quake lifted up a low, wet area that had been only a minor camping and food-processing site and turned it into a higher, drier spot that eventually became home to a major permanent settlement with several longhouses (Campbell, 1981; Blukis Onat, 1987). Native peoples described and commemorated geologic events in their oral traditions by using descriptive metaphors based on their cultural concepts, often ascribing earth shaking to actions of supernatural beings. In this paper we discuss stories about a’yahos, a supernatural spirit power that natives associated with five locales along the trace of the Seattle Fault. Three of these locales are associated with landslides, and another has a description of offset consistent with the movement of the Seattle Fault. In 1985, prior to published evidence of the A.D. 900 earthquake on the Seattle Fault, an article in the Seattle Weekly (Buerge, 1985) mentioned a “spirit boulder” associated with earthquakes and landslides located near the Fauntleroy ferry dock in west Seattle. The proximity of this location to the Seattle Fault invited investigation, and we discovered that the Fauntleroy spirit boulder is associated with a supernatural being called a’yahos, which is often described in a way that could refer to earthquake effects and particularly landslides. The a’yahos is a shape-shifter, often appearing as an enormous serpent, sometimes double-headed with blazing eyes and horns, or as a composite monster having the forequarters and head of a deer and the tail of a snake (Mohling, 1957). A’yahos is associated with shaking and rushes of turbid water and comes simultaneously from land and sea (Smith, unpublished notes). “At the spot where a’yahos came to a person the very earth was torn, land slides occurred and the trees became twisted and warped. Such spots were recognizable for years afterward” (Smith, 1940). Figure 1 shows an artifact from a non-Salish tribe on the outer coast of Washington that corresponds to the description of a’yahos and represents a vicious guardian spirit. Stories about a’yahos mention a number of specific locales in the central Puget Sound, along the Hood Canal, and on the Strait of Juan de Fuca as far west as the Elwha River. Thirteen a’yahos locales are mentioned in various stories (Figures 2 and 3). While some locales are identified precisely, rather general location descriptions (e.g., “Dungeness River”) are given for others. A’yahos sites appear to coincide generally with shallow faults around the Puget Lowland, including the Little River Fault along the strait of Juan de Fuca, the Seattle and Tacoma Faults, and the Price Lake scarps (Haugerud et al., 2003). Five of the a’yahos story sites are spatially concentrated and located very close to the trace of the Seattle Fault (Figure 3). Four of the Seattle locales can be associated with land- 1. Department of Earth and Space Sciences, University of Washington 2. Program on the Environment and Department of History, University of Washington 3. Anthropologist 4. Historian 5. FEMA 6. Duwamish Tribe cultural resources expert 7. Snoqualmie Tribe cultural resources expert and great-grandson of James Zackuse, Duwamish Indian doctor Seismological Research Letters July/August 2005 Volume 76, Number 4 427 ▲ Figure 1. A Quileute ceremonial representation of a two-headed horned serpent with legs; known as a vicious guar