26 km of offset on the Lake Clark fault since late Eocene time

Aeromagnetic data over the Lake Clark Fault reveal a north-trending band of magnetic anomalies that are right-laterally offset about 26 km across the fault. The magnetic anomalies correlate spatially with a belt of dated 34-39-Ma granitic plutons. Thus, the Lake Clark Fault has had ~26 km of right-lateral offset in the past 34-39 Ma. The Castle Mountain Fault, which lies along the strike of the Lake Clark Fault to the east-northeast, must have had a similar or, possibly, greater amount of offset. We infer the presence of an additional right-lateral strike-slip fault about 35 km northwest of the Lake Clark Fault, herein named the 'Telequana Fault,' on the basis of 11 km of right-lateral offset of a north-trending band of magnetic anomalies.