Thrust-breakthrough of folds southwest of Galbraith Lake, central Brooks Range, Alaska
Thesis (M.S.) University of Alaska Fairbanks, 2002 Detailed mapping of a 32 square-kilometer area in the fold-and-thrust belt of the north-central Brooks Range indicates that fault-related folds in the Lisburne Limestone formed as detachment folds and were subsequently cut by thrust faults. Thrust f...
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Format: | Thesis |
Language: | English |
Published: |
2002
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Online Access: | http://hdl.handle.net/11122/6282 |
Summary: | Thesis (M.S.) University of Alaska Fairbanks, 2002 Detailed mapping of a 32 square-kilometer area in the fold-and-thrust belt of the north-central Brooks Range indicates that fault-related folds in the Lisburne Limestone formed as detachment folds and were subsequently cut by thrust faults. Thrust faulting resulted in a duplex structure with a floor thrust in the Kayak Shale and a roof thrust in the Siksikpuk Formation. The linking thrusts of the duplex dip toward the hinterland while the floor and roof thrusts dip toward the foreland indicating that the duplex has been tilted by underlying structures. I constructed models for the sub-lisburne structure to account for the structural geometry observed in the study area. Duplexing of the Kanayut Conglomerate is the most likely cause of the forward tilt, but thickening of the Kayak Shale or deformation beneath the basal thrust of the Endicott Mountains allochthon may also contribute. |
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