Paper No. 1
Presentation Time: 9:00 AM
THE INFLUENCE OF CLIMATE AND TECTONICS ON TOPOGRAPHY IN THE HAYES RANGE, ALASKA
Climate influences glaciation; glaciation and tectonics change topography; topography influences climate.Tectonically active, glaciated mountain ranges like the Southern Alaska orogen illustrate this complex feedback system particularly well. While the high topography of the Denali massif in the western Alaska Range has been studied to some extent, much less is known about that of the Hayes Range. The main objectives of this study are to determine mean elevation distribution in the Hayes Range and identify evidence for structural, lithological, and/or erosional control(s). I use geospatial information systems (GIS) software to map mean elevation, calculate geomorphic indices from a digital elevation model (DEM), and characterize climatic/glacial, tectonic, and topographic patterns. I focus on an area of the Hayes Range between the Wood and Delta Rivers. In the northern part of the range, recently recognized Quaternary deformation is clearly defined by a geomorphic surface that is uplifted and deformed by doubly plunging anticlines and thrust faults. A similar distribution of elliptical topographic highs is present farther south, but Quaternary structures are more difficult to identify because of increased glaciation and erosion. Emergent general patterns include correspondence between mean elevation and regional equilibrium line altitude of glaciers (ELA) and potential coupling of precipitation and topographic variability.