HR: 1340h
AN: T23C-0566    [Abstracts]
TI: Quantitative Analysis of Glaciated Landscapes
AU: * Huerta, A D
EM: ahuerta@geosc.psu.edu
AF: Pennsylvania State University, 407 Deike Bldg, University Park, PA 16802 United States
AB: The evolution of glaciated mountains is at the heart of the debate over Late Cenozoic linkages between climate and tectonics. Traditionally, the development of high summit elevations is attributed to tectonic processes. However, much of the high elevation of the Transantarctic Mountains can be attributed solely to uplift in response to glacial erosion (Stern et al., 2005). The Transantarctic Mountains (TAM) provide an unparalleled opportunity to study glacial erosion. The mountain range has experienced glacial conditions since Oligocene time. In the higher and dryer regions of the TAM there is only a thin veneer of ice and snow draping the topography. In these regions landforms that were shaped during earlier climatic conditions are preserved. In fact, both glacial and fluvial landforms dating as far back as 18 Ma are preserved locally. In addition, the TAM are ideal for studying glacial erosion since the range has experienced minimal tectonic uplift since late Oligocene time, thus isolating the erosion signal from any tectonic signal. With the advent of digital data sets and GIS methodologies, quantitative analysis can identify key aspects of glaciated landscape morphology, and thus develop powerful analytical techniques for objective study of glaciation. Inspection of USGS topographic maps of the TAM reveals that mountain tops display an extreme range of glacial modification. For example, in the Mt. Rabot region (83°-84° S), mountain peaks are strongly affected by glaciation; cirque development is advanced with cirque diameters on the range of several kilometers, and cirque confluence has resulted in the formation of ``knife-edge'' arêtes up to 10 km long. In contrast, in the Mt. Murchison area (73°-74° S) cirque development is youthful, and there is minimal development of arêtes. Preliminary work indicates that analysis of DEM's and contour lines can be used to distinguish degree of glaciation. In particular, slope, curvature, and power spectrum analysis reveal characteristics that capture the development of cirques and arêtes.
DE: 0776 Glaciology (1621, 1827, 1863)
DE: 1819 Geographic Information Systems (GIS)
DE: 1824 Geomorphology: general (1625)
DE: 8175 Tectonics and landscape evolution
SC: Tectonophysics [T]
MN: Fall Meeting 2005