The landslide tsunami of November 3, 1994, Skagway Harbor, Alaska

Abstract

We show that the tsunami of November 3, 1994 in Skagway, Alaska was generated by an underwater landslide formed during the collapse of a cruise ship wharf undergoing construction at the head of Taiya Inlet. This event occurred at a time of extreme low tide and was not associated with a regional seismic event or incoming oceanic tsunami. Persistent wave motions with an amplitude of 1 m and a period of 3 min recorded by a tide gauge in Skagway Harbor following the landslide are linked to the formation of a cross‐inlet seiche and quarter‐wave resonance within the harbor. The high Q factor for the harbor ( Q ≈ 20) indicates weak dissipation and strong resonance within the harbor.