Ahmet Cevdet Yalciner

Modeling of the November 3, 1994 Skagway, Alaska Tsunami

In the evening of November 3, 1994, a series of submarine landslides and associated waves destroyed the Pacific Arctic Railway Company (PARN) dock at Skagway, Alaska, killing one construction worker. Numerous geologic and hydrodynamic studies followed, in an effort to prove or disprove that construction failure was responsible for initiating the slide. We model the slide using two inundation models, the model known as TUNAMI--N2 (not TSUNAMI) developed at Tohoku University and the model VTCS--3 developed at the University of Southern California and now in use by NOAA and known as MOST. Both models when run under the same initial conditions and bathymetry provided consistent results about the hydrodynamic motions close to the PARN dock. The results qualitatively fit the eyewitness observations, using a combination of three slides, and suggest that the sliding started offshore along the fjord wall off the southern end of the dock and undermined the southern two thirds of the dock.