A century-plus record of work has established the formation pathways by which periglacial processes give rise to entire landscapes. Sedimentological facies, discrete deposits that represent the interactions of climate and topography in an environment, comprise the basis of a concept used in periglacial contexts to interpret paleoclimatic depositional processes and to better characterize landforms. Geographical periglacial geomorphology, a once popular trend in the German literature, established that regional-scale relationships exist between periglacial landform assemblages and the climatic snowline, thus outlining the three-dimensional distribution of upland periglacial features.Recent periglacial literature calls into question the ability of periglacial processes to generate landform-scale terrain. Motivated by such skepticism, this dissertation focuses on quantitative and qualitative characterization of periglacial regions. Four interrelated but independent chapters in this dissertation use facies and geographical periglacial geomorphology frameworks to 1) identify trends in periglacial feature elevations in relict periglacial environments; 2) identify periglacial facies in known periglacial realms; 3) characterize and map facies; and 4) apply findings from facies and spatial-analytical studies to interpret enigmatic features of hypothesized periglacial origin. Chapter 2 is a regional-scale spatial analysis of periglacial features in the Appalachian Highlands providing unifying and important spatial context for the subsequent periglacial studies put forth in this dissertation. A synthesis of published periglacial features and locational information shows that a strong correlation exists between periglacial feature elevation and reconstructed climate trends from the Last Glacial Maximum, lending support to the climatic interpretation of upland Appalachian terrain. Chapter 3 focuses on quantitative characterization of the composition and spatial distribution of upland “periglacial facies” in the Alaskan interior. Sedimentological and remotely sensed data demonstrate that cryoplanation surfaces are comprised of areas delimited by distinct topographic and sedimentological characteristics. Chapter 4 focuses on periglacial terrain at Spruce Knob in West Virginia’s section of the Appalachian Highlands. Data collection and analysis of this hypothesized cryoplanation landform and comparison to the site from Chapter 3 supports the interpretation that the periglacial components of Spruce Knob align with the morphological characteristics of an upper side slope facet. Chapter 5 is a case study that utilizes methodology from previous chapters to elucidate the formation of the enigmatic Hickory Run Boulder field (HRBF), located in northeastern Pennsylvania. Field data show that the HRBF likely formed via an allochthonous pathway characterized by tributary-like flow of blocky material from bedrock outcrops. Evidence for the integration of clasts from an under investigated area of the boulder field was found, offering new insights into the feature’s formation. Results from this dissertation show that the periglacial imprint is evident and observable, based on periglacial facies, which impart a distinct “footprint” on the landscape. Major findings indicate that 1) the areal distribution of periglacial features in the eastern USA aligns with European findings showing trends in feature elevations; 2) periglacial cryoplanated terrain is composed of faceted surfaces representing topographic and microclimatic variations; and 3) paleoperiglacial processes, combined with glacio-fluvial activity, can result in the formation of large boulder (block) fields that can accurately be described as periglacial features.
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