Thesis (M.S.)--University of Wisconsin, 1971. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 70-72).

The tallest mountain in North America, Mount McKinley is situated inside a sharp bend in the right‐lateral Denali fault. This anomalous topography is clearly associated with the complex geometry of the Denali fault, but how this topography evolves in conjunction with the adjacent strike‐slip fault is unknown. To constrain how this fault bend is deforming, the Quaternary fault‐related deformation on the opposite side of the Denali fault from Mount McKinley were documented through combined geologic mapping, active fault characterization, and analysis of background seismicity. My mapping illustrates an east‐west change in faulting style where normal faults occur east of the fault bend and thrust faults predominate to the west. These faults offset glacial outwash terraces and moraines which, with tentative correlations with the regional glacial history, provide fault slip rates that suggest that the Denali fault bend is migrating southwestward. The complex and elevated regional seismicity corroborates the style of faulting associated with the fault bend and provide additional subsurface control on the location of active faults. Seismologic and neotectonic constraints suggest that the maximum compressive stress axis rotates from vertical east of the bend to horizontal and Denali fault‐normal west of the bend.

<p>This file contains all U-Pb zircon geochronology results collected at the University of Arizona -  Laserchron Center and Washington State University</p> <p><br></p> <p>Detailed datasets include laser settings and counts per second for each analysis</p> <p><br></p> <p>See summary for all U-Pb detrital zircon analyses for GPS, geographic location, and sample name. This data table can be used for guidance to each raw dataset. Additionally, summary datatable files are grouped into Western, Central, and Eastern Stratigraphic packages. Information sheets provide additional information for U-Pb methods.</p> <p><br></p> <p>Samples: FTUPbICP-1248-1, FTUPbICP-1248-2, FTUPbICP-1248-3  are samples analyzed at Washington State University for Jeffrey Benowitz</p> <p><br></p> <p>All other samples were analyzed at the University of Arizona Laserchron Center <em><strong>( NSF-EAR 1649254</strong></em><strong>  </strong>)</p>

xvi, 121 p. : ill. (some col.), maps (some col.) Also includes two large-scale maps in two separate pdf files. A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / Deformation across plate boundaries often occurs over broad zones with relative motions between plates typically accommodated by faults of different styles acting together in a complex system. Collision of the Yakutat microplate within the Alaskan portion of the Pacific-North America plate boundary drives deformation over 600 km away where the Denali fault divides predominantly rigid crustal block motions of southern Alaska from distributed deformation in central Alaska. Quaternary geologic mapping along the Nenana River valley and the Japan Hills of the northern foothills of the Alaska Range defines zones of Quaternary thrust faulting recorded in the progressive deformation of Pleistocene fluvial terraces. I use topographic profiles of these terraces and paleoseismic trenching of fault scarps to characterize the Quaternary activity and constrain the subsurface geometry of these faults. Radiocarbon and cosmogenic exposure dating methods provide age control on the stratigraphy in the trenches and landforms offset by these faults. These observations define a 1-1.5 mm/yr slip rate for the Gold King fault which changes laterally from a north-vergent thrust into a north and south vergent thrust wedge that uplifts the Japan Hills. Along the Nenana River valley, the progressive deformation of Pleistocene surfaces defines a north-vergent critically-tapered thrust wedge. The geometry of progressive uplift and folding requires a near planar, south-dipping basal thrust fault with two major north-dipping backthrusts. All three faults were active simultaneously on a scale of 10 4 yrs with slip rates of 0.25-1 mm/yr, until the late Pleistocene when we infer the retreat of glacial ice from the main axis of the Alaska Range caused a change in thrust wedge dynamics. I use the orientation of Quaternary deformation north of the Denali fault to show that strain is highly partitioned and establish geologic constraints on the regional horizontal stress orientation. North of the Denali fault, fault-normal principal shortening accommodates 3-5 mm/yr of strain transfer across the Denali fault system. Two appendices contain additional results of paleoseismic trenching and neotectonic investigations across 4 active faults near the Nenana River. This dissertation includes previously unpublished co-authored material. / Committee in charge: Ray Weldon, Chairperson, Geological Sciences; Joshua Roering, Member, Geological Sciences; David Schmidt, Member, Geological Sciences; Douglas Kennett, Outside Member, Anthropology