The neotectonics, uplift, and accommodation of deformation of the Talkeetna Mountains, south-central Alaska

South-central Alaska is home to many tectonic structures and mountain ranges that have experienced active uplift and deformation within the past 5 to 10 Ma. The Talkeetna Mountains are located above the area of flat-slab subduction of the Yakutat microplate. I hypothesize that the Talkeetna Mountains have been uplifted as a result of this underlying flat-slab subduction and that areas of the Talkeetna Mountains are neotectonically active.;The Talkeetna Mountains are deforming heterogeneously across four different structural domains defined by differences in geomorphic patterns, seismicity, dominant fault types, and the orientation of horizontal maximum stress (SHmax). A strain partitioning structure divides the northern and southern domains, and is observed by a change in SHmax orientation from E-W in southern domains to NW-SE in the northern domain. The strain partition is accommodated by a crustal break along the Talkeetna thrust fault, which is expressed at the surface as a wide zone of deformation.;Apatite fission-track analysis suggests two distinct periods of uplift: one dated from 45 to 30 Ma and another from approximately 10 Ma to present, with uplift rates of 0.14 mm/yr and 0.24 mm/yr, respectively. The first phase of uplift coincides with a time of significant plate reorganization in the north Pacific which resulted in translation of terranes northwestward. The second phase of uplift correlates with Neogene accretion of the Yakutat microplate. I propose that the majority of Neogene deformation and uplift in the Talkeetna Mountains is due to far-field deformation in the upper plate above the subducting slab. Variations in both composition of the crust and depth to the downgoing slab resulted in strain partitioning and northwest-directed compression in the northern Talkeetna Mountains and northwest compression and warping in the southern Talkeetna Mountains.