T90 Megathrusts: 50 Years after the 1964 Great Alaska Earthquake—In Honor of George Plafker
Monday, 20 October 2014
8:00 AM - 12:00 PM
116/117
SLIP ON THE SUCKLING HILLS SPLAY FAULT DURING THE 1964 ALASKA EARTHQUAKE
Paper number: T90-6
Program: Technical Sessions
Time: 9:05 AM – 9:20 AM
Authors
-
Julie ElliottPurdue University, West Lafayette, IN
-
Diane DoserUniversity of Texas at El Paso, El Paso, TX
-
Terry PavlisUniversity of Texas at El Paso, El Paso, TX
Abstract
The Suckling Hills in southern Alaska experienced localized, anomalously high coseismic uplift in the Mw 9.2, 1964 Alaska earthquake. High uplift at the Suckling Hills can be explained by increased slip, or an asperity, on the Aleutian megathrust, however, this paper suggests that increased uplift may be a result of slip on the Suckling Hills splay fault. We present a series of models that demonstrate how the inclusion of the Suckling Hills fault improves the fit between modeled vertical displacement and measured coseismic uplift in comparison to slip on the Aleutian megathrust alone. Our results suggest ~3m of slip on the Suckling Hills fault during the 1964 earthquake can explain the high coseismic uplift data. These results are consistent with recent studies indicating Pleistocene slip on the Suckling Hills fault and together highlight the potential seismic and tsunami risk associated with this segment of the Alaskan subduction complex.