Abstract

A magnitude 5.7 mb (5.2 Ms) earthquake occurred on 14 August 1984, 14 km north of Sutton, in the vicinity of the mapped trace of the Talkeetna segment of the Castle Mountain fault system. The focal mechanism of the earthquake and the spatial distribution of well-controlled aftershock hypocenters indicate that the shock involved dextral slip at 13- to 20-km depth on the Talkeetna fault segment. The depth of the shocks is consistent with the lack of observed surface breakage. The Sutton earthquake sequence, plus recent small shocks recorded by the southern Alaska seismograph network, provide definitive evidence that the Talkeetna segment of the fault system is active.

First Page Preview

First page PDF preview
You do not currently have access to this article.