Active faults of Alaska
Abstract
Geologically young displacements have been observed along 24 faults in an area of Alaska of approximately 624,000 km 2. Active faults of southern Alaska include the Patton Bay and Hanning Bay reverse-slip faults, both reactivated in 1964. The Fairweather strike-slip fault experienced surface faulting in 1958 and possibly in 1899. Three normal-slip faults trending northerly were not reactivated in 1964; these are the Johnstone Bay fault, Ragged Mountain fault, and the Long Glacier fault. The Castle Mountain fault trends northeasterly and is marked by a low, south-facing escarpment. Active faults in the Alaska Range and adjacent areas include those of the Denali fault system, including the Totschunda fault and the McGinnis Glacier fault; inactive faults include the Hines Creek fault. Other active faults include the Donnelly Dome fault, the Granite Mountain fault, and the Healy Creek fault. The north front of the Alaska Range west of Donnelly Dome is a monocline with few associated surface faults. The Clearwater Lake fault, located along the Tanana River east of Delta Junction, appears to be active, although an origin of landforms due to faulting cannot be proven. Active faults in the Tanana—Kuskokwim Lowland and Yukon—Tanana Upland include the Minto, Shaw Creek, Champion Creek, and Tintina faults. The active Kaltag fault, located southwest of Tanana, does not appear to connect by means of an active trace with the Tintina fault, which is 300 km to the east. Active faults of the Kokrine—Hodzana Highlands include the Kanuti and Dall Mountain faults. Active faults west of the Kanuti include the Huslia and a fault along Shoestring Sand Dune, both in the Koyukuk Flats. The active Kobuk—Alatna Hills fault trends westerly south of the Brooks Range. No active faults were observed in the central and eastern Brooks Range, Arctic Foothills, or Arctic Coastal Plain in the area of study.
- Publication:
-
Tectonophysics
- Pub Date:
- December 1975
- DOI:
- 10.1016/0040-1951(75)90134-1
- Bibcode:
- 1975Tectp..29...73B